# Diagnostic criteria of forearm Chronic Exertional Compartment Syndrome: A systematic review

Thomas Hirardot, Germain Pomares, Pierre Menu, Jérôme Grondin, Marc Dauty, Alban Fouasson-Chailloux

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Thomas Hirardot, Germain Pomares, Pierre Menu, Jérôme Grondin, Marc Dauty, et al. Diagnostic criteria of forearm Chronic Exertional Compartment Syndrome: A systematic review. Orthopaedics & Traumatology: Surgery & Research, 2024, 10.1016/j.otsr.2024.104001. hal-04801671

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Review article

# Diagnostic criteria of forearm Chronic Exertional Compartment Syndrome:
A systematic review

Thomas Hirardot<sup>a,b</sup>, Germain Pomares<sup>c,d</sup>, Pierre Menu<sup>a,b,e,f</sup>, Jérôme Grondin<sup>a,b</sup>,
Marc Dauty<sup>a,b,e,f</sup>, Alban Fouasson-Chailloux<sup>a,b,c,d,e,f,*</sup>

ARTICLE INFO

Keywords:

Chronic Exertional Compartment Syndrome

Sport

Pain

Diagnostic

Intra-compartmental pressure

A B S T R A C T

**Background:** Chronic Exertional Compartment Syndrome (CECS) of the forearm is characterized by an increase of the pressure in the forearm compartments during repeated activities. Its diagnosis is challenging because of the lack of clearly established diagnostic criteria.

**Purpose:** We aimed to provide a comprehensive description of the diagnostic methods used for CECS of the forearm, to assess if a more effective diagnosis strategy could be identified.

**Methods:** We used PubMed, Google Scholar, Cochrane Library and Science Direct databases to search articles. We carried out multiple searches using the mesh terms ("Chronic Exertional Compartment Syndrome" OR "Chronic compartment syndrome" OR "Exertional compartment") AND ("arm" OR "upper limb"). Inclusion criteria were prospective or retrospective studies on CECS of the forearm including case reports. We used PRISMA guidelines. The included studies were critically appraised using GRADE approach.

**Results:** A total of 625 articles were screened and 33 studies were included. It represented 590 patients (505 men and 85 women), with a mean age of 26.6 years old. Among them, 282 competed at an elite level. Motorcycling and motocross were the most frequent sports (66%). Six diagnostic methods were employed. Intra-compartmental pressure (ICP) measurement was the most frequently used method in 26 studies. Magnetic resonance imaging was performed in 9 studies, while electromyography was employed in only 2 studies. One study reported the measurement of grip strength using a manual dynamometer, one study compared forearm circumference before and after effort, and one used myotonometry. Various exercise protocols were observed. Stress-testing using a hand-grip was the most common protocol in 14 studies. Exercise duration varied from 2 min to 60 min.

**Conclusion:** Existing data do not provide sufficient evidence to favor an alternative diagnostic method over ICP measurements that should be used cautiously given the absence of formal validation. Non-invasive methods might be easier to use, but should be subjected to further research.

**Level of evidence:** III.

# 1. Introduction

Chronic Exertional Compartment Syndrome (CECS) of the forearm is a poorly known condition characterized by an increase of the pressure in the forearm compartments during repeated activities. Its estimated prevalence stands approximately at 8.9% among amateur and

professional motorcycle riders [1]. Other sports associated to CECS of the forearm include: climbing, weightlifting, rowing, baseball, tennis, windsurfing and water skiing [2-4].

The initial treatment consists of a non-surgical strategy, including adaptation of sports equipment and rehabilitation. In case of ineffective conservative treatment, surgery can be considered, enabling athletes to

<footnote><sup>a</sup> Service de Médecine Physique et Réadaptation Locomotrice et Respiratoire, CHU Nantes, Nantes Université, 44093 Nantes, France</footnote>

<footnote><sup>b</sup> Service de Médecine du Sport, CHU Nantes, Nantes Université, 44093 Nantes, France</footnote>

<footnote><sup>c</sup> Institut Européen de la Main, Hôpital Kirchberg, L2540 Luxembourg, Luxembourg</footnote>

<footnote><sup>d</sup> Medical Training Center, Hôpital Kirchberg, L2540 Luxembourg, Luxembourg</footnote>

<footnote><sup>e</sup> Inserm, UMR 1229, RMeS, Regenerative Medicine and Skeleton, ONIRIS, Nantes Université, 44042 Nantes, France</footnote>

<footnote><sup>f</sup> Institut Régional de Médecine du Sport (IRMS), 44093 Nantes, France</footnote>

<footnote>* Corresponding author at: MPR Locomotrice, CHU de Nantes, Hôpital St Jacques, 85 Rue Saint Jacques, Cedex 1, 44093 Nantes, France.</footnote>

<footnote>E-mail address: alban.fouassonchailloux@chu-nantes.fr (A. Fouasson-Chailloux).</footnote>
return to sport activities in around 80% of the cases [5]. Several surgical options are available, including open fasciotomy, partial fasciotomy and endoscopic techniques, all these options show comparable success rates [6].

The diagnosis of CECS is currently challenging because of the lack of clearly established diagnostic criteria. The current criteria rely on clinical history, intra-compartmental pressure (ICP) measurement and, less frequently, MRI or electromyography [7]. In most cases, the decision to practice a surgical intervention is based on clinical history and intra-compartmental pressure measurement. However, there is no consensus on the pressure thresholds to use, and in practice several ones are used, the Pedowitz criteria, originally validated for CECS of the lower limbs [8], the Whitesides and Heckman criteria, initially developed for acute compartment syndrome, and others suggesting to lower the pressure threshold at >10 mmHg at rest and >20 mmHg at 1 and 5 min after exercise [9,10].

Because of the diversity of the diagnostic methods and pressure thresholds used, a synthesis of available evidence was needed. In this systematic review we aimed to provide a comprehensive description of the diagnostic methods used for Chronic Exertional Compartment Syndrome of the forearm, to assess if a more effective diagnosis strategy could be identified.

## 2. Materials and methods

### 2.1. Literature search

This systematic review was registered in PROSPERO under the registration number CRD42023465971. We used the PubMed, Google Scholar, Cochrane Library and Science Direct databases to search articles in September 2023. The study period extended from 1983 to August 2023. The search was performed independently by two of the authors to assess titles and abstracts of potentially relevant articles, and then the full-text articles were retrieved. After identification of key articles, their references and citation lists were also hand-searched. When consensus was not reached about an article inclusion, a third assessor's advice was required. We carried out multiple searches using the mesh terms ("Chronic Exertional Compartment Syndrome" OR "Chronic compartment syndrome" OR "Exertional compartment") AND ("forearm" OR "upper limb").

### 2.2. Inclusion and exclusion criteria

Inclusion criteria were prospective or retrospective studies on CECS of the forearm including case reports. The studied populations were adults and children. Studies had to be written in English. The diagnosis procedure for CECS had to be precisely described (clinical, MRI, ICP, EMG). Studies with insufficient data, relating to acute compartment syndrome or CECS of the lower limb, and studies in which pressure values were not reported, were excluded from the review.

### 2.3. Data extraction

All the included studies were analyzed, and data were extracted and summarized in tables using Microsoft Excel (Version 2016, Microsoft Corporation, Redmond, WA, USA): study design, year of publication, reported outcomes. Collected data were: patient demographics, sports activity or practice, level of sport, duration of symptoms, involved compartments, surgical intervention. The diagnostic method was entered, as well as information relating to the measurement (device model, patient position during measurement, time of measurement). Mean pressure values at rest and after exercise were reported when available. Charts were made using R studio software (version 2022.07.1, Build 554).

### 2.4. Quality analysis

We used PRISMA guidelines for this review [11]. The included studies were critically appraised using GRADE approach [12], in order to evaluate quality of evidence. GRADE approach classifies the quality of evidence in one of four levels: high, moderate, low, and very low. Case reports were excluded from the GRADE analysis as, by definition, they have a low level of evidence.

## 3. Results

### 3.1. Study selection

Details of the screening results are shown in Fig. 1. A total of 625 articles were found, after excluding duplicate or irrelevant articles, 63 articles were retained based on their titles. After reading abstracts, 42 articles were assessed for full text reading. A total of 33 relevant publications were included in the study.

### 3.2. Demographic data

A total of 33 studies were included [2-4,9,10,13-40]. It represented 590 patients (505 men and 85 women), with a mean age of 26.6 years. Among them, 282 competed at an elite level: national, international, or professional (Table 1).

Motorcycling and motocross were the most frequently encountered sports in this study, involving 393 patients (66%). Other sports were less prevalent: rock climbing involved 23 patients (3.8%), weightlifting 19 patients (3.2%), tennis 5 patients (0.8%), and baseball 4 patients (0.6%). Manual activity was involved in 10 cases (1.6%): one metal fitter [33], one carpenter, one motor mechanic [36], one assembly worker [39], and a truck driver [27], 5 other patients had manual occupations but without any more precision [16,26]. One patient was a sale clerk with symptoms occurring while handwriting [33]. For 94 patients, activity or sport was not reported. The average duration of symptoms before diagnosis was 17.5 months. Quality assessment of the studies is reported in Table 2.

### 3.3. Diagnostic methods

A total of 6 diagnostic methods were employed (Table 3), 5 out of the 33 studies used two different diagnosis methods [13,28,31,35,40]. Intra-compartmental pressure (ICP) measurement was the most frequently used diagnostic method, reported in 26 studies [2,9,10,13,15, 17-23,25-29,32-40]. Magnetic resonance imaging (MRI) was performed in 9 studies [3,4,14,16-19,24,28,35], while electromyography (EMG) was employed in only 2 studies [31,40]. Additionally, one study reported the measurement of grip strength using a manual dynamometer [13], one study compared forearm circumference before and after effort [30], and one used myotonometry [31]. The distribution of patients based on the diagnostic method is outlined in Fig. 2.

### 3.4. Exercise protocols and time of measurement

Various exercise protocols were observed among the studies. Stress-testing, achieved by repetitive finger flexion-extension using a hand-grip, was the most common protocol, identified in 14 studies [2,10, 16-18,20,21,22,23,24,28,37]. Wrist-weighted curls [40], forearm pro-nation-supination and wrist flexion-extension [39], wrist and finger flexion-extension to the point of intense pain [36], were also reported. In two studies, exercise was specific to the sporting activity: gripping the brake of a motorcycle handle bar at 150 pound-force/square inch (PSI) [13], and motocross race exercises [28].

In terms of exercise duration, the reported time varied widely among studies, ranging from 2 min [13,32] to 60 min [39]. Some authors used symptom reproduction such as forearm pain, tightness, and cramping [3], or complete exhaustion [14,20] as the cut-off point.
<figure><img src="image_3.png" /><figcaption>Fig. 1. Flow chart of the included studies.</figcaption></figure>

Regarding the time of measurement, MRI studies typically conducted scans at rest and immediately after the exercise protocol. Raphael et al. [3] reported post-exertion multiple scans with 5-min intervals for a total of 15 min.

For ICP measurements, they were taken mostly at rest, then immediately after exercise. In 3 studies, measurements were made during exercise [29,36,38], and in one case, additional measurements were performed during exercise, immediately after exercise, and at 1 and 10 min post-exercise [9]. During the recovery period, the most frequent measurement time was at 5 min [17,18,20,22], although in one study it was extended to 30 min [10].

### 3.5. Grip strength measurement

O'Dowd et al. [13] conducted a hand grip strength measurement protocol with a handheld grip strength dynamometer (Takei®, TKK 5401 Grip D) and a forearm flexor compartment pressure measurement, in eleven patients. They observed mean pre-exercise grip strength of 50.6 mmHg (37.0–66.7 mmHg). Following the onset of CECS symptoms a statistically significant decrease of 30.0% (range 18.6%–53.8%) was noted, resulting in mean post-exercise grip strength of 35.6 mmHg (range 17.1–52.5 mmHg). The mean pre-exercise forearm compartment pressures of 11.7 mmHg (range 7.0–17.0 mmHg) significantly increased in post-exercise at 30.5 mmHg (range 15.0–45.0 mmHg). Yet, no significant association was found between the amount of change in compartment pressure and the amount of change in grip strength.

### 3.6. Forearm circumference

Piasecki et al. [30], reported the case of a 27-year-old athlete, for whom the diagnosis of CECS of the left forearm was based solely on clinical criteria. A protocol of 5–10 min of resisted left forearm exercises with weights was applied, and forearm circumference was measured at 7.5 cm of the medial epicondyle and compared to the resting values. At rest, the forearm circumference was 30.0 cm on the right and 30.8 cm on the left. Following the exercise protocol, an increase in the left forearm circumference to 31.2 cm was reported.

### 3.7. Electromyography

In the study by Korhonen et al. [31], quantitative surface EMG was employed in 37 patients, on the muscles of the dorsal forearm compartment, concurrently with ICP measurement. A correlation was found between ICP and EMG amplitude at 20% and 40% maximum voluntary contraction (r = 0.747, p < 0.0001). Mean EMG amplitudes values at the contraction levels of 75% and 100% maximum voluntary contraction were found to be higher in subjects with pathological ICP values than in those with ICP values in the normal range.

Kutz et al. [40] reported the case of a 40-year-old man, who underwent assessment of median nerve velocity following a resisted pro-nation protocol. At rest, a nerve conduction velocity of 67.5 m/s proximal to the wrist was measured, which decreased to 58.6 m/s after 10 min of stress.
<table><caption>**Table 1**
Demographic data of the studies.</caption><thead><tr><th>Study</th><th>Diagnostic method</th><th>Total patients, (n)</th><th>Control group, (n)</th><th>Mean age (years)</th><th>Sex (M/F)</th><th>Sport or activity (n)</th><th>Sport level (n)</th><th>Symptoms (n)</th><th>Symptoms location (n)</th><th>Symptoms duration (months)</th><th>Positive response to surgical treatment, n (%)</th></tr></thead><tbody><tr><td>O'Dowd et al. [13]</td><td>ICP/GS</td><td>11</td><td>-</td><td>NS</td><td>11/0</td><td>Motorcycle (11)</td><td>National</td><td>Forearm pain</td><td>Right forearm (11)</td><td>33.5</td><td>NA</td></tr><tr><td>Badenhorst et al. [14]</td><td>MRI</td><td>5</td><td>4</td><td>20.25</td><td>4/1</td><td>NS</td><td>NS</td><td>Pain</td><td>Right forearm (3)</td><td>NS</td><td>5 (100%)</td></tr><tr><td>Guerzider et al. [15]</td><td>ICP</td><td>30</td><td>-</td><td>25</td><td>29/1</td><td>Motocross (26)</td><td>Recreational (9)</td><td>Tightness cramping Muscle hardening, acroparesthesia, cramps, swelling, edema</td><td>Forearm (27)</td><td>60</td><td>29 (96%)</td></tr><tr><td>Tominaga et al. [16]</td><td>MRI</td><td>5</td><td>-</td><td>24.6</td><td>5/0</td><td>Trail (2)<br/>Endurance (2)<br/>3 Motocross (3)<br/>Baseball pitcher (1)<br/>Manual laborer (1)<br/>Motorcycling (6)</td><td>Regional (11)<br/>National (10)<br/>Professional (1)<br/>NS (4)</td><td>Pain muscle weakness</td><td>Thenar (3)<br/>1 interosseous space (1)<br/>Bilateral (3)</td><td>NS</td><td>3 (60%)</td></tr><tr><td>Schiavi et al. [17]</td><td>ICP</td><td>9</td><td>-</td><td>16.2</td><td>9/0</td><td>Motocross (3)</td><td>National (5)<br/>International (4)</td><td>Pain, tightness, stiffness, cramping, swelling, paresthesia, loss of strength</td><td>Right forearm 6<br/>Bilateral 3</td><td>11</td><td>9 (100%)</td></tr><tr><td>Barrera-Ochoa et al. [2]</td><td>ICP</td><td>124</td><td>-</td><td>25</td><td>124/0</td><td>Motorcycling (47)<br/>Motocross (24)<br/>Mountain climbing (22)<br/>Weightlifting (19)<br/>Water skiing (8)<br/>Tennis players (4)<br/>Motorcycling (39)</td><td>Professional or high intensity athletes (124)</td><td>Pain, tightness, stiffness, cramping, swelling, paresthesia, loss of strength</td><td>Bilateral (27)</td><td>>6</td><td>NA</td></tr><tr><td>Gondolini et al. [18]</td><td>ICP</td><td>54</td><td>-</td><td>23</td><td>54/0</td><td>Motocross (15)</td><td>Professional (54)</td><td>Pain, tightness, stiffness, cramping, swelling, paresthesia, loss of strength</td><td>Right forearm (25)<br/>Left forearm (6)<br/>Bilateral (23)</td><td>12.5</td><td>52 (96%)</td></tr><tr><td>Abe and Fujii [4]</td><td>MRI</td><td>1</td><td>-</td><td>15</td><td>0/1</td><td>Tennis (1)</td><td>Recreational (1)</td><td>Pain Swelling</td><td>Right forearm (1)<br/>Right forearm (1)<br/>Bilateral (22)<br/>Unilateral (12)</td><td>NS</td><td>1 (100%)</td></tr><tr><td>Cole et al. [19]</td><td>ICP</td><td>1</td><td>-</td><td>21</td><td>0/1</td><td>Softball (1)</td><td>Collegiate (1)<br/>International (19)<br/>National (27)</td><td>Burning, tingling</td><td>Bilateral (22)<br/>Unilateral (12)</td><td>6</td><td>1 (100%)</td></tr><tr><td>Barrera-Ochoa et al. [20]</td><td>ICP</td><td>34</td><td>-</td><td>24</td><td>34/0</td><td>Motocross (34)</td><td>National (27)</td><td>Pain</td><td>Right forearm (2)<br/>Loss of strength Swelling</td><td>28</td><td>3 (100%)</td></tr><tr><td>Pegoli et al. [21]</td><td>ICP</td><td>3</td><td>-</td><td>25.3</td><td>3/0</td><td>NS</td><td>NS</td><td>Pain, weakness, swelling of the forearm</td><td>Bilateral (1)<br/>Right forearm (1)</td><td>12</td><td>1 (100%)</td></tr><tr><td>Winkes et al. [22]</td><td>ICP</td><td>1</td><td>-</td><td>26</td><td>1/0</td><td>Motorcycling (1)<br/>Motorcycling (4)<br/>Other (1)</td><td>NS</td><td>Pain</td><td>Bilateral (4)<br/>Muscular hypertrophy</td><td>14</td><td>4 (100% of the patients who underwent surgery)</td></tr><tr><td>García-Mata [10]</td><td>ICP</td><td>5</td><td>-</td><td>16.8</td><td>4/1</td><td>NS</td><td>NS</td><td>Pain</td><td>Right forearm (1)</td><td>NS</td><td>6 (100%)</td></tr><tr><td>Harrison et al. [23]</td><td>ICP</td><td>6</td><td>-</td><td>NS</td><td>6/0</td><td>Rowing (6)</td><td>National and international (6)</td><td>Loss of strength</td><td>Bilateral (6)</td><td>NS</td><td>6 (100%)</td></tr></tbody></table>

(continued on next page)
<table><caption>Table 1 (continued)</caption><thead><tr><th>Study</th><th>Diagnostic method</th><th>Total patients, (n)</th><th>Control group, (n)</th><th>Mean age (years)</th><th>Sex (M/F)</th><th>Sport or activity (n)</th><th>Sport level (n)</th><th>Symptoms (n)</th><th>Symptoms location (n)</th><th>Symptoms duration (months)</th><th>Positive response to surgical treatment, n (%)</th></tr></thead><tbody><tr><td>Jans et al. [24]</td><td>MRI</td><td>154</td><td>-</td><td>32.7</td><td>151/3</td><td>Motocross (154)</td><td>NS</td><td>Altered sensation in the hands<br>Pain</td><td>Bilateral (154)<br>Bilateral (23)</td><td>NS</td><td>153 (99%)</td></tr><tr><td>Winkes et al. [9]</td><td>ICP</td><td>24</td><td>-</td><td>34 ± 8</td><td>24/0</td><td>Motocross (24)</td><td>International (7)<br>National (9)<br>Local (8)</td><td>Pain during racing (21)<br>Pain during normal activities in daily life (11)<br>Loss of muscle strength (18)<br>Cramps (14)<br>Pain<br>Tightness cramping</td><td>Unilateral (1)<br>Right forearm (1)</td><td>NS</td><td>24 (100%)</td></tr><tr><td>Raphael et al. [3]</td><td>MRI</td><td>1</td><td>-</td><td>31</td><td>1/0</td><td>Baseball (1)</td><td>Major league (1)</td><td>Pain<br>Paresthesia<br>Pain<br>Tightness cramping<br>Tingling</td><td>Right forearm (1)<br>Right forearm (1)<br>Bilateral (10)<br>Left forearm (1)</td><td>12</td><td>1 (100%)</td></tr><tr><td>O'hEireamhoin et al. [25]</td><td>ICP</td><td>1</td><td>-</td><td>20</td><td>0/1</td><td>Rowing (1)<br>Motorcycling (4)<br>Manual work (4)<br>Motocross (1)<br>Rowing (1)<br>Windsurfing (1)<br>Rock-climbing (1)<br>Martial art (1)</td><td>Elite (1)</td><td>Weakness and numbness of the hands</td><td>Right forearm (1)</td><td>3.5</td><td>11 (91%)</td></tr><tr><td>Brown et al. [26]</td><td>ICP</td><td>12</td><td>-</td><td>29.5</td><td>11/1</td><td>Truck driver (1)</td><td>NA</td><td>Pain<br>Loss of strength Swelling<br>Pain<br>Tightness</td><td>Left forearm (1)<br>Bilateral (5)</td><td>10</td><td>1 (100%)</td></tr><tr><td>Hijjawi et al. [27]</td><td>ICP</td><td>1</td><td>-</td><td>33</td><td>1/0</td><td>Motocross (5)</td><td>Professional or high intensity (5)</td><td>Pain<br>Tightness</td><td>Bilateral (5)</td><td>15.6</td><td>NA</td></tr><tr><td>Gielen et al. [28]</td><td>MRI</td><td>5</td><td>5</td><td>25.6</td><td>5/0</td><td>Motocross (5)</td><td>Professional (8)</td><td>Pain<br>Tightness</td><td>Bilateral (8)</td><td>18</td><td>8 (100%)</td></tr><tr><td>Croutzet et al. [29]</td><td>ICP</td><td>8</td><td>-</td><td>23</td><td>8/0</td><td>Motorcycle (8)</td><td>Olympic (1)</td><td>Weakness</td><td>Left forearm (1)</td><td>12</td><td>1 (100%)</td></tr><tr><td>Piasecki et al. [30]</td><td>FC</td><td>1</td><td>-</td><td>27</td><td>1/0</td><td>Kayak (1)</td><td>NS</td><td>Pain<br>Pain<br>Paresthesia</td><td>NS</td><td>NS</td><td>NA</td></tr><tr><td>Korhonen et al. [31]</td><td>EMG/MYO</td><td>37</td><td>-</td><td>42.5</td><td>15/22</td><td>NS</td><td>NS</td><td>Pain<br>Pain<br>Paresthesia</td><td>NS</td><td>NS</td><td>NA</td></tr><tr><td>Pritchard et al. [32]</td><td>ICP</td><td>42</td><td>25</td><td>NS</td><td>15/52</td><td>NS</td><td>NS</td><td>Pain<br>Para-Olympian (1)<br>Professional (1)</td><td>Bilateral (4)<br>Loss of strength</td><td>NS</td><td>6 (100%)</td></tr><tr><td>Zandi [33]</td><td>ICP</td><td>6</td><td>-</td><td>25.8</td><td>6/0</td><td>Wheelchair athlete (1)<br>Motorcycling (1)<br>Mountain climbing (1)<br>Water skiing (1)<br>Other (2)</td><td>NA (4)</td><td>Tightness</td><td>Right forearm (2)</td><td>NS</td><td>6 (100%)</td></tr><tr><td>Goubier and Saillant [34]</td><td>ICP</td><td>2</td><td>-</td><td>26.5</td><td>2/0</td><td>Motorcycling (2)</td><td>Professional (1)<br>NS (1)</td><td>Weakness<br>Pain<br>Tingling<br>Pain<br>Weakness Swelling<br>Pain<br>Weakness Swelling<br>Pain<br>Weakness Swelling<br>Pain<br>Professional (1)</td><td>Right forearm (2)<br>Bilateral (1)<br>Bilateral (2)</td><td>NS</td><td>2 (100%)</td></tr><tr><td>Hider et al. [35]</td><td>ICP/MRI</td><td>1</td><td>-</td><td>47</td><td>1/0</td><td>NS</td><td>NS</td><td>Pain<br>Tingling<br>Pain<br>Weakness Swelling<br>Pain<br>Weakness Swelling<br>Pain<br>Weakness Swelling<br>Pain<br>Professional (1)</td><td>Bilateral (1)<br>Bilateral (2)</td><td>84</td><td>1 (100%)</td></tr><tr><td>Söderberg [36]</td><td>ICP</td><td>2</td><td>-</td><td>26</td><td>2/0</td><td>Carpenter (1)<br>Motor mechanic (1)<br>Gymnastic and Field Hockey (1)<br>Motorcycling (1)</td><td>NA</td><td>Pain<br>Weakness Swelling<br>Pain<br>Weakness Swelling<br>Pain<br>Weakness Swelling<br>Pain<br>Professional (1)</td><td>Bilateral (1)<br>Bilateral (1)<br>Bilateral (1)<br>Bilateral (1)<br>Bilateral (1)</td><td>6</td><td>2 (100%)</td></tr><tr><td>Wasilewski and Asdourian [37]</td><td>ICP</td><td>1</td><td>-</td><td>14</td><td>0/1</td><td>NS</td><td>NS</td><td>Pain<br>Weakness Swelling<br>Pain<br>Weakness Swelling<br>Pain<br>Weakness Swelling<br>Pain<br>Professional (1)</td><td>Bilateral (1)<br>Bilateral (1)<br>Bilateral (1)<br>Bilateral (1)<br>Bilateral (1)</td><td>6</td><td>1 (100%)</td></tr><tr><td>Allen and Barnes [38]</td><td>ICP</td><td>1</td><td>-</td><td>32</td><td>1/0</td><td>Assembly worker (1)</td><td>NA</td><td>Pain<br>Weakness Swelling<br>Pain<br>Weakness Swelling<br>Pain<br>Weakness Swelling<br>Pain<br>Weakness Swelling<br>Pain<br>Professional (1)</td><td>Bilateral (1)<br>Bilateral (1)<br>Bilateral (1)<br>Bilateral (1)<br>Bilateral (1)<br>Bilateral (1)</td><td>NS</td><td>1 (100%)</td></tr><tr><td>Pedowitz and Toutounghi [39]</td><td>ICP</td><td>1</td><td>-</td><td>22</td><td>0/1</td><td>Assembly worker (1)</td><td>NA</td><td>Pain<br>Weakness Swelling<br>Pain<br>Dysesthesia<br>Weakness Swelling<br>Pain</td><td>Right forearm (1)<br>Right forearm (1)</td><td>4</td><td>1 (100%)</td></tr><tr><td>Kutz et al. [40]</td><td>ICP/EMG</td><td>1</td><td>-</td><td>40</td><td>1/0</td><td>NA</td><td>NA</td><td>Pain</td><td>Right forearm (1)</td><td>6</td><td>1 (100%)</td></tr></tbody></table>
**Abbreviations:** EMG = electromyogram; FC = forearm circumference; GS = grip strength; ICP = intra compartmental pressure; MRI: magnetic resonance imaging; MYO = myotonometry; NS: not specified; NA: not applicable.

<table><caption>**Table 2**

Evaluation of the level of evidence using GRADE approach.</caption><thead><tr><th>Study</th><th>Design</th><th>Level of evidence</th><th>Limitation in study design or execution</th><th>Inconsistency of results</th><th>Indirectness of evidence</th><th>Imprecision</th><th>Quality of evidence</th></tr></thead><tbody><tr><td>O'Dowd et al. [13]</td><td>Case series</td><td>IV</td><td>+</td><td>-</td><td>-</td><td>+</td><td>Low</td></tr><tr><td>Tominaga et al. [16]</td><td>Case series</td><td>IV</td><td>++</td><td>+</td><td>-</td><td>+</td><td>Low</td></tr><tr><td>Barrera-Ochoa et al. [2]</td><td>Retrospective cohort</td><td>IV</td><td>+</td><td>-</td><td>-</td><td>-</td><td>Moderate</td></tr><tr><td>García-Mata [10]</td><td>Case series</td><td>IV</td><td>++</td><td>-</td><td>-</td><td>+</td><td>Low</td></tr><tr><td>Brown et al. [26]</td><td>Case series</td><td>IV</td><td>+</td><td>-</td><td>-</td><td>+</td><td>Low</td></tr><tr><td>Korhonen et al. [31]</td><td>Diagnosis study</td><td>II</td><td>+</td><td>+</td><td>-</td><td>+</td><td>Moderate</td></tr><tr><td>Pritchard et al. [32]</td><td>Case series</td><td>IV</td><td>++</td><td>-</td><td>-</td><td>+</td><td>Low</td></tr><tr><td>Guerzider et al. [15]</td><td>Retrospective cohort</td><td>IV</td><td>+</td><td>-</td><td>-</td><td>-</td><td>Low</td></tr><tr><td>Gondolini et al. [18]</td><td>Case series</td><td>IV</td><td>+</td><td>-</td><td>-</td><td>-</td><td>Moderate</td></tr><tr><td>Schiavi et al. [17]</td><td>Case series</td><td>IV</td><td>+</td><td>-</td><td>-</td><td>-</td><td>Moderate</td></tr><tr><td>Barrera et al. [20]</td><td>Case series</td><td>IV</td><td>+</td><td>-</td><td>-</td><td>-</td><td>Moderate</td></tr><tr><td>Jans et al. [24]</td><td>Case series</td><td>IV</td><td>++</td><td>-</td><td>-</td><td>+</td><td>Low</td></tr><tr><td>Harrison et al. [23]</td><td>Case series</td><td>IV</td><td>++</td><td>-</td><td>-</td><td>++</td><td>Low</td></tr><tr><td>Winkes et al. [9]</td><td>Case series</td><td>IV</td><td>+</td><td>-</td><td>-</td><td>-</td><td>Moderate</td></tr><tr><td>Croutzet et al. [29]</td><td>Case series</td><td>IV</td><td>++</td><td>-</td><td>-</td><td>+</td><td>Low</td></tr><tr><td>Zandi [33]</td><td>Case series</td><td>IV</td><td>++</td><td>-</td><td>-</td><td>+</td><td>Low</td></tr><tr><td>Badenhorst et al. [14]</td><td>Cross-sectional descriptive pilot study</td><td>IV</td><td>+</td><td>-</td><td>-</td><td>+</td><td>Low</td></tr><tr><td>Gielen et al. [28]</td><td>Diagnosis study</td><td>II</td><td>+</td><td>-</td><td>-</td><td>-</td><td>Low</td></tr><tr><td>Pegoli et al. [21]</td><td>Case series</td><td>IV</td><td>+</td><td>-</td><td>-</td><td>-</td><td>Low</td></tr></tbody></table>

Legend: ++ = important bias; + = bias; - = no bias.

### 3.8. Magnetic resonance imaging

In this review, MRI studies cover the period from 2002 to 2021. Most studies primarily utilized T2-weighted sequences changes in signal intensity. Some authors described the use of T1-weighted sequences [14, 28]. Intensity of the magnetic field was reported in three studies. Examinations were performed on either a 1-Tesla MRI [35], a 1.5-Tesla MRI [14,28] or a 3-Tesla MRI [14]. Main findings were the increase of post-exertional signal intensities in T2-weighted sequences, on either volar or dorsal compartment, as well as in relevant muscles such as brachio-radialis [4] or flexor digitorum profundus [3].

Badenhorst et al. [14] reported a statistically significant difference in the signal intensity ratio between CECS patient and a control group (p = 0.001).

Jans et al. [24] found a residual increase of the signal intensity in 28 (18%) of the 154 patients of their study after fasciotomy.

Gielen et al. [28] noticed an increase in the flexor digitorum superficialis, and profundus in all CECS patients, while observing a minor increase in a non-symptomatic group of motocross racers.

### 3.9. Myotonometry

Myotonometry was employed by Korhonen et al. [31] in 2005 for diagnosing CECS of the forearm. The mechanical characteristics of the muscle were assessed both at rest and during isometric contractions. The results indicated a significant linear increase in the elastic properties of the muscle (MYOfreq) with relative muscle load (p < 0.05), even if no statistically significant difference was found in the viscous properties of the muscle (MYOdec) during maximum voluntary contraction. A significant correlation was observed in the dorsal forearm, between MYOfreq and ICP measurement (r = 0.487–0.855, p < 0.0001) both at

rest and during muscle load.

### 3.10. Intra-compartmental pressure measurements

In the 26 studies involving ICP measurement, a wide range of exercise protocols and measurement times was observed. Four studies reported catheter angle ranging from 30° to 45° [9,13,20,28], but no study reported catheter depth. Details of pressure measurement values are provided in Fig. 3. When measured at rest, mean ICP values were below the 15-mmHg-Pedowitz criteria in 10 studies, accounting for 47% of the total studies with available data. When ICP measurements were carried out immediately following the exercise, mean ICP measurement remained below the 30 mmHg threshold in two cases [27,32].

At the 1 min mark, 2 studies had mean ICP measurement above 30 mmHg [17,22], while 6 (75% of the total studies with available data) recorded measurement below this threshold.

Mean ICP measurement at 5 min post-exercise remained below the 20 mmHg mark in 1 case [32].

Regarding pressure thresholds, half of the studies used the Pedowitz criteria [15,18–21,23,25,27,28,33–36] (Table 4). Brown et al. [26] and Croutzet et al. [29] reported using a threshold for abnormality of 30 mmHg, regardless of the time of measurement, while Harrison et al. [23] accepted a rise of 10 mmHg with exertion, regardless of the baseline. Several authors used lowered thresholds values (Table 4):

- García-Mata [10] used >10 mmHg pressure at rest, >20 mmHg at 1 min, >20 mmHg after 5 min as abnormal ICP values, and 15 min as a maximum ICP normalization time after exertion;

- Winkes et al. [9,22] used a pressure >10 mmHg at rest, and >20 mmHg at 1 and 5 min after provocation;
<table><caption>**Table 3**
Diagnostic methods.</caption><thead><tr><th>Studies</th><th>Diagnosis method</th><th>Exercise protocol</th><th>Measurement equipment</th><th>Patient positioning</th><th>Catheter positioning (if applicable)</th><th>Compartment</th><th>Timing of measurement</th><th>Main outcomes/measure results</th></tr></thead><tbody><tr><td>O'Dowd et al. [13]</td><td>ICP</td><td>Handle bars clamped to a table, griping a brake at 150PSI over a 2-min period</td><td>Calibrated portable Stryker®</td><td>Hand supinated and the elbow extended</td><td>45° to horizontal</td><td>Deep flexor compartment right arm</td><td>At rest, and immediately after exercise</td><td>Mean pre-exercise pressure: 11.7 mmHg (7–28 mmHg), post-exercise: mean 30.5 mmHg (15–45 mmHg)</td></tr><tr><td>O'Dowd et al. [13]</td><td>Grip strength</td><td>Handle bars clamped to a table, griping brake at 150 PSI over a 2-min period</td><td>Takei®, TKK 5401 Grip D handheld grip strength dynamometer</td><td>NS</td><td>NA</td><td>Deep flexor compartment right arm</td><td>At rest, and immediately after exercise</td><td>Mean pre-exercise: right hand grip strength 50.6 mmHg (37–66.7 mmHg) post-exercise: mean of 35.6 mmHg (17.1–52.5 mmHg)</td></tr><tr><td>Tominaga et al. [16]</td><td>Post-exertional MRI</td><td>“Grip and release” using a hand gripper with maximum effort for approximately 10 min until symptoms occurred</td><td>NS</td><td>NS</td><td>NA</td><td>NA</td><td>Pre-exertional MRI at rest/post-exertional MRI after 10 min of exercise</td><td>Post-exertional T2 weighted MRI showed increased signal intensities in FDS and FDP. This T2 signal intensity remained on post-exertional MRI after fasciotomy in patients who still had symptoms (2) and disappeared completely in patients without remaining symptoms (3).</td></tr><tr><td>Barrera-Ochoa et al. [2]</td><td>ICP, with evaluation of a new variable: Trest</td><td>Finger flexion/ extension (Handgrip) until physical exhaustion or pain</td><td>Stryker® ICP monitor</td><td>Extensor ICP: pronation, with the elbow flexed to 90°. Flexor ICP: supinated with the elbow fully extended</td><td>Flexor compartment pressure: as described by McCarthy et al., extensor compartment pressure: as described by Gelberman et al.</td><td>Flexor and extensor compartment based on symptomatology</td><td>At rest (PRest), immediately after exercise (Pmax) after 1 and 5 min post. TRest = time between PMax and the return to Rest</td><td>Accuracy with standard ICP diagnostic variables was lower (SN 73%, SP 84%, PPV 97%, NPV 31%) than with TRest (SN 100%, SP 94%, PPV 99%, and NPV 100%).</td></tr><tr><td>García-Mata [10]</td><td>ICP</td><td>Repeated handgrip squeezing with a manual digital dynamometer until the symptoms were induced, in all case after 10–15 min exercise</td><td>Stryker® ICP monitor STIC catheter</td><td>Patient supine (upper/lower extremities at heart level)</td><td>NS</td><td>Flexor and extensor compartment based on symptomatology</td><td>Baseline, immediately after exercise, and 1, 5, 10, 15, 20, 25, and 30 min after exercise</td><td>Most of the patients had at rest pressure of >10 mmHg and/or >20 mmHg after 200, and they all needed >150 for ICP normalization Three of the patients had new ICP measurement 1 year after the surgery, where the values were normal and lower than their preoperative counterparts.</td></tr><tr><td>Brown et al. [26]</td><td>ICP</td><td>Repeated squeezing of a sphygmomanometer bulb. Repeated flexion and extension of the wrist holding a 3 kg dumbbell Repeated gripping of a fixed bar and performing an isometric pull with palms facing up and then with palms facing down</td><td>Spectramed® P10 EZ pressure transducer</td><td>Forearm horizontal and hand resting on the thigh</td><td>NS</td><td>Flexor and extensor compartment based on symptomatology</td><td>Immediately after exercise</td><td>All patients had peak pressure above >30 mmHg, 11 of 12 patients were satisfied after fasciotomy, 1 patient was dissatisfied</td></tr></tbody></table>

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<table><caption>Table 3 (continued)</caption><thead><tr><th>Studies</th><th>Diagnosis method</th><th>Exercise protocol</th><th>Measurement equipment</th><th>Patient positioning</th><th>Catheter positioning (if applicable)</th><th>Compartment</th><th>Timing of measurement</th><th>Main outcomes/measure results</th></tr></thead><tbody><tr><td>Korhonen et al. [31]</td><td>EMG and myometry</td><td>Short-term and long-term isometric contractions</td><td>EMG: ME3000P Stryker® ICP monitor myotonometer</td><td>Lying on the bed in a natural position without any extra stretch</td><td>NS</td><td>Extensor compartment</td><td>At rest and at maximum load</td><td>Mean values of EMG amplitudes at the contraction levels of 75% and 100% maximum voluntary contraction (MVC) and MYOOfreq values at all contraction levels (0%-100% MVC) were higher for subjects with pathological values of ICP than for those with ICP values in the normal range.</td></tr><tr><td>Pritchard et al. [32]</td><td>ICP</td><td>2 min repetitive gripping exercise using a standard dynamometer linked to a computer readout, gripping to near-maximum strength at an approximate rate of one grip every 1-2 s</td><td>Pressure-sensitive probe (Kodiag; B. Braun Medical)</td><td>NS</td><td>NS</td><td>Extensor compartment</td><td>At rest, immediately after exercise, then for 5 min at intervals of 1 min</td><td>Mean peak ICP between 4 and 6 mmHg in asymptomatic and volunteer group. ICP values &gt;6 mmHg at rest in the CECS group, rising up to a mean between 15 and 20 at peak</td></tr><tr><td>Guerzider et al. [15]</td><td>ICP</td><td>NS</td><td>Stryker® ICP monitor</td><td>NS</td><td>NS</td><td>NS</td><td>At rest, immediately after exercise and then 10 min after exercise</td><td>All patients had ICP above 20mmHg 10 min after exercise in at least 1 compartment.</td></tr><tr><td>Gondolini et al. [18]</td><td>ICP</td><td>Hand grip test</td><td>Low-pressure digital transducer</td><td>NS</td><td>NS</td><td>Superficial volar compartment dorsal compartment</td><td>At baseline, immediately after exercise, and 5 min after exercise</td><td>Mean baseline value of 9.3 ± 3.7 (range 2-16), mean value of 30.5 ± 7.5 (range 24-37) 1 min after exercise, mean value of 22.6 ± 6.1 (range 18-26) 5 min after exercise</td></tr><tr><td>Gondolini et al. [18]</td><td>MRI</td><td>Hand grip test</td><td>NS</td><td>NS</td><td>NA</td><td>FDS, FDP, ECRL</td><td>Post exertional MRI after hand grip test</td><td>Increase in signal intensity on T2-weighted sequences in the FDS and FDP in all cases; in addition, a minor signal intensity increase was noted in the ECRL</td></tr><tr><td>Schiavi et al. [17]</td><td>ICP</td><td>Hand grip test</td><td>Low-pressure digital transducer</td><td>NS</td><td>NS</td><td>Superficial volar compartment and in the dorsal compartment</td><td>At baseline, immediately after exercise, and 5 min after exercise</td><td>Mean ICP pre-exercise: 8.3 mmHg; at 1 min after exercise: 31 mmHg; at 5 min after exercise 21.4 mmHg</td></tr><tr><td>Schiavi et al. [17]</td><td>MRI</td><td>Hand grip test</td><td>NS</td><td>NS</td><td>NA</td><td>FDS, FDP</td><td>Post exertional MRI after hand grip test</td><td>Increase in signal intensity on T2-weighted sequences in the FDS and FDP in all cases; minor signal intensity increase in the extensor carpi radialis longus</td></tr></tbody></table>

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<table><caption>**Table 3 (continued)**</caption><thead><tr><th>Studies</th><th>Diagnosis method</th><th>Exercise protocol</th><th>Measurement equipment</th><th>Patient positioning</th><th>Catheter positioning (if applicable)</th><th>Compartment</th><th>Timing of measurement</th><th>Main outcomes/measure results</th></tr></thead><tbody><tr><td>Barrera et al. [20]</td><td>ICP</td><td>Handgrip test (IronMind, Ann Arbor, Michigan)</td><td>pressure monitor device 783547; Hewlett-Packard, Palo Alto, California</td><td>NS</td><td>NS</td><td>Deep forearm flexor compartment</td><td>At rest (PRest), immediately after exercise (Ppain) after 1 and 5 min post exercise (P1min, P5 min) TRest = time between PMax and the return to Prest</td><td>Prest 7.1 ± 3.9 mmHg Ppain 32.3 ± 3.7 mmHg P1min 7.1 ± 3.2 mmHg P5 min 21.3 ± 3.5 mmHg T rest 19.7 ± 3.1 min. Only 2 patients met the Pedowitz criteria of "30 mmHg at 1 min after exercise" (sensitivity of 5.9%). Thirty-three patients met the Pedowitz criteria of "20 mmHg at 5 min after exercise" (sensitivity of 97%).</td></tr><tr><td>Jans et al. [24]</td><td>MRI</td><td>Repetitive grip until exhaustion for 15 min</td><td>NS</td><td>NS</td><td>NS</td><td>NS</td><td>Before and after strenuous exercise of the hand flexors</td><td>In 28 cases (18.2%), slight edema was seen on the post-exercise MRI</td></tr><tr><td>Harrison et al. [23]</td><td>ICP</td><td>grip strength test</td><td>arterial line pressure transducer on an anesthetic trolley</td><td>NS</td><td>NS</td><td>Flexor and extensor compartment</td><td>At rest and immediately after exercise</td><td>Average readings were 10.4 mmHg volar and 10.8 mmHg dorsal at rest, increasing to 47.3 and 40.4 mmHg, respectively, on exertion. In the final three cases, treatment was offered based on a clear clinical history of CECS and invasive monitoring was not felt necessary.</td></tr><tr><td>Winkes et al. [9]</td><td>ICP</td><td>Repetitive palmar flexion of the wrist against resistance</td><td>Indwelling Slit Catheter Set, Stryker Instruments, Kalamazoo, Michigan. Pressure monitor device 783547, Hewlett Packard, Palo Alto, California</td><td>Sitting in an armchair with one arm lying flat on a table</td><td>45° to horizontal</td><td>Flexor and extensor compartment</td><td>Before, during, immediately after, and 1 and 5 min after the provocation</td><td></td></tr><tr><td>Croutzet et al. [29]</td><td>ICP, clinical examination</td><td>NS</td><td>NS</td><td>NS</td><td>NS</td><td>Superficial volar compartment and dorsal compartment</td><td>During effort</td><td>For 6 patients: results were positive (over 30 mmHg during effort) for all compartments of the 2 forearms for 4 patients, positive only for the volar compartment for 1 patient, positive in only 1 forearm for 1 patient. For 2 patients, the pressure was measured only for the volar compartment: these 2 results were negative. Indeed,</td></tr></tbody></table>

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<table><caption>Table 3 (continued)</caption><thead><tr><th>Studies</th><th>Diagnosis method</th><th>Exercise protocol</th><th>Measurement equipment</th><th>Patient positioning</th><th>Catheter positioning (if applicable)</th><th>Compartment</th><th>Timing of measurement</th><th>Main outcomes/measure results</th></tr></thead><tbody><tr><td>Zandi [33]</td><td>ICP</td><td>Repetitive dumbbell flexion at the wrist</td><td>Stryker (Kalamazoo, MI, USA) sideport needle</td><td>NS</td><td>NS</td><td>Flexor compartment</td><td>Post exercise pressure</td><td>the diagnosis for these 2 patients was only based on the clinical examination. Post-exercise pressures: 32 mmHg, 98 mmHg, 44 mmHg, 43 mmHg, 42 mmHg. After 5–10 min rest: 33 mmHg, 38 mmHg, 36 mmHg</td></tr><tr><td>Hijjawi et al. [27]</td><td>ICP</td><td>Repetitively contract and relax his left forearm flexor muscles</td><td>Stryker (Kalamazoo, MI, USA) sideport needle</td><td>NS</td><td>NS</td><td>Volar compartment</td><td>Post exercise pressure</td><td>Post exercise pressure of 28 mmHg</td></tr><tr><td>Badenhorst et al. [14]</td><td>MRI</td><td>Concentric hand squeezes of a foam ball up to the point of symptom onset or exhaustion</td><td>1.5-T MRI or 3-T MRI</td><td>NS</td><td>NA</td><td>Muscle involved: ECR, ECU, ED, BR, Sup, AP, FDP, FDS, FPL, FCR (1)</td><td>Immediately after exercise</td><td>Statistically significant difference (p = 0.001) in the SIR between the control (1.3 ± 0.2) and patient (1.5 ± 0.2) groups. Magnetic resonance imaging after exercise showed an increase in SI and SNR in the muscles on T2.</td></tr><tr><td>Gielen et al. [28]</td><td>MRI</td><td>Stress of the forearm flexor and extensor muscles by using a finger flexion-extension exercise tool bilaterally until exhaustion with a maximum of 15 min (Handgrip; Domyos, Taipei, Taiwan).</td><td>Symphony, 1.5-Tesla magnet; Siemens, Erlangen, Germany</td><td>Procubitus with both arms extended, and a large flex coil was used to cover both forearms</td><td>NA</td><td>FDS, FDP, FCU and ECRL</td><td>Immediately after exercise</td><td>Magnetic resonance imaging after exercise showed an increase in SI and SNR in the muscles on T2.</td></tr><tr><td>Gielen et al. [28]</td><td>ICP</td><td>Motocross race exercise</td><td>Stryker Instruments, Kalamazoo, MI, USA</td><td>NS</td><td>Introduction into the proximal third of the forearm in the mid-line at an angle of 30° to the medial side</td><td>Deep flexor compartment</td><td>At rest and after exercise</td><td>–</td></tr><tr><td>Pegoli et al. [21]</td><td>ICP</td><td>Squeeze a hand grip trainer with a resistance of 20 kg for two minutes and after, a second hand grip with a resistance of approximately 40 kg</td><td>Stryker Instruments, Kalamazoo, MI, USA</td><td>NS</td><td>NS</td><td>NS</td><td>At rest and after exercise, and 5 min after rest</td><td>–</td></tr><tr><td>Cole et al. [19]</td><td>ICP</td><td>Burpees, push-ups, and medicine ball tosses until pain and tightness in the forearm were felt</td><td>NS</td><td>NS</td><td>NS</td><td>Dorsal and volar mid-forearm areas</td><td>Pre-exercise, 3 min post-exercise, and 5 min post-exercise</td><td>10 mmHg 3 min post exercise 30 mmHg 5 min post-exercise</td></tr><tr><td>Cole et al. [19]</td><td>MRI</td><td>Same protocol as ICP</td><td>NS</td><td>NS</td><td>NS</td><td>Flexor and extensor compartments</td><td>Pre and immediately after exercise</td><td>Post exercise IRM: edema within the FCR, FDS FCU, and ECRB and ECRL</td></tr><tr><td>Winkes et al. [22]</td><td>ICP</td><td>Maximal provocation test using fitness grippers</td><td>NS</td><td>NS</td><td>NS</td><td>Flexor and extensor compartments</td><td>At baseline, immediately after exercise, at 1 min and 5 min after exercise</td><td>Diffuse, intense T2 signal in the FDP muscle belly immediately post</td></tr><tr><td>Raphael et al. [3]</td><td>MRI</td><td>Squeeze a firm exercise ball repeatedly until</td><td>NS</td><td>NS</td><td>NS</td><td>Flexor and extensor compartments</td><td>Immediately post exertion, and then at 5-min intervals</td><td>Diffuse, intense T2 signal in the FDP muscle belly immediately post</td></tr></tbody></table>

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<table><caption>**Table 3 (continued)**</caption><thead><tr><th>Studies</th><th>Diagnosis method</th><th>Exercise protocol</th><th>Measurement equipment</th><th>Patient positioning</th><th>Catheter positioning (if applicable)</th><th>Compartment</th><th>Timing of measurement</th><th>Main outcomes/measure results</th></tr></thead><tbody><tr><td>O'hEireamhoin et al. [25]</td><td>ICP</td><td>NS</td><td>NS</td><td>NS</td><td>NS</td><td>Flexor compartment</td><td>At rest</td><td>exertion that washed out significantly at 15 min post exertion<br>Compartment pressure testing of the volar compartments confirmed a raised resting pressure of 20 mmHg.</td></tr><tr><td>Wasilewski and Asdourian [37]</td><td>ICP</td><td>Repetitive handgrip squeezing of a dynamometer</td><td>NS</td><td>NS</td><td>NS</td><td>NS</td><td>At rest and immediately after exercising to the point of pain</td><td>Pressure at rest: 25 mmHg in the right forearm and 31 mmHg in the left forearm. After exercise: 46 mmHg in the right forearm and 36 mmHg in the left forearm.</td></tr><tr><td>Piasecki et al. [30]</td><td>Forearm circumference</td><td>5-10 min of resisted left forearm exercises with weights</td><td>NA</td><td>NA</td><td>NA</td><td>NA</td><td>After exercise</td><td>Increase of 0,4 cm left forearm circumference (31.2 cm), after 10 min exercise.</td></tr><tr><td>Allen and Barnes [38]</td><td>ICP</td><td>Flexing fingers squeezing bulb gripping bar</td><td>NS</td><td>NS</td><td>NS</td><td>Flexor compartment</td><td>During exercise</td><td>Resting pressure of 10 mmHg in both superficial and deep flexor compartment in both forearms, elevating up to 48 mmHg in the right forearm during exercise.</td></tr><tr><td>Goubier and Saillant [34]</td><td>ICP</td><td></td><td>Howmedica, Mahway, NJ, USA</td><td>NS</td><td>NS</td><td>Flexor compartment</td><td>Before exercise After 15 min of exercise 15 min after exercise 30 min after exercise</td><td></td></tr><tr><td>Abe and Fujii [4]</td><td>MRI</td><td>NS</td><td>NS</td><td>NS</td><td>NS</td><td>Lateral compartment</td><td>NS</td><td>MRI: high intensity in the BR muscle belly</td></tr><tr><td>Kutz et al. [40]</td><td>ICP</td><td>Resisted pronation with the elbow extended after a preliminary work period of resisted gripping and wrist-weighted curls</td><td>Howmedica, Mahway, NJ, USA</td><td>NS</td><td>NS</td><td>Flexor compartment</td><td>Before exercise After 30 min of exercise 10 min after exercise 35 min after exercise</td><td>Baseline 23 mmHg<br>After 30 min of exercise 42.5 mmHg 10 min after exercise 35.5 mmHg 35 min after exercise 24mmHg</td></tr><tr><td>Kutz et al. [40]</td><td>EMG</td><td>Resisted pronation with the elbow extended after a preliminary work period of resisted gripping and wrist-weighted curls</td><td>TECA electromyograph model M. Evoked</td><td>NS</td><td>NS</td><td>Median nerve</td><td>Immediately after exercise</td><td>Nerve conduction velocity of 67.5 m/s proximal to the wrist at rest and 58.6 m/s after stress of 10 min.</td></tr><tr><td>Pedowitz and Toutounghi [39]</td><td>ICP</td><td>Forearm pronation-supination and wrist flexion-extension for 60 min</td><td>Howmedica, Mahway, NJ, USA</td><td>NS</td><td>NS</td><td>Flexor compartment</td><td>At rest 5 min after exercise</td><td>Rest pressures were 6 mmHg on the right and 4 mmHg on the left Five minutes after exercise pressures were 32 mmHg on the right and 8 mmHg on the left</td></tr><tr><td>Söderberg [36]</td><td>ICP</td><td>Elbow in extension and with wrist and finger</td><td>NS</td><td>NS</td><td>NS</td><td>Volar and dorsal compartment and anconeus 1</td><td>At rest During exercise</td><td>29 mmHg and 27 mmHg, at rest the pressures</td></tr></tbody></table>

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<table><caption>**Table 3 (continued)**</caption><thead><tr><th>Studies</th><th>Diagnosis method</th><th>Exercise protocol</th><th>Measurement equipment</th><th>Patient positioning</th><th>Catheter positioning (if applicable)</th><th>Compartment</th><th>Timing of measurement</th><th>Main outcomes/measure results</th></tr></thead><tbody><tr><td></td><td></td><td>flexion-extension to the point of intense pain for 5 min</td><td></td><td></td><td></td><td>short abductor muscle of the thumb</td><td></td><td>increased to a maximum of 108 mmHg and 236 mmHg, respectively 14 mmHg but was elevated on exercise to 32 mmHg</td></tr><tr><td>Hider et al. [35]</td><td>ICP</td><td>Several minutes of repetitive wrist flexion and extension</td><td>NS</td><td>NS</td><td>NS</td><td>Dorsal compartment</td><td>At rest, immediately after exercise, 2 min after exercise</td><td>The left forearm showed a resting pressure of 33 mmHg, increasing to 144 mmHg after several minutes of repetitive wrist flexion and extension. After 2 min of rest the pressure decreased to 62 mmHg.</td></tr><tr><td>Hider et al. [35]</td><td>MRI</td><td>Several minutes of repetitive wrist flexion and extension</td><td>NS</td><td>NS</td><td>NS</td><td>Dorsal compartment</td><td>At rest, immediately after exercise</td><td>MRI: high signal change within the extensor muscles of the forearm, indicating edema,</td></tr></tbody></table>

**Abbreviations:** EMG = electromyogram; FC = forearm circumference; GS = grip strength; ICP = intra compartmental pressure; MRI: magnetic resonance imaging; MYO = myotonometry; NS: not specified; NA: not applicable; PSI = pound per square inch; mmHg = millimeters of mercury; FDS = flexor digitorum superficialis; FDP = flexor digitorum profundus; ECR = extensor carpi radialis; ECU = extensor carpi ulnaris; ED = extensor digitorum; BR = brachioradialis; FCR = flexor carpi radialis; Prest = pressure at rest; Pmax = pressure immediately after exercise; Trest = time between pressure immediately after exercise and return to baseline; SN = sensitivity; SP = specificity; PNV = predictive negative value; PPV = predictive positive value; MVC = maximum voluntary contraction; MYOfreq = elastic properties of the muscle in myotonometry.

<figure><img src="image_4.png" /><figcaption>**Fig. 2.** Distribution of the patients by diagnostic methods.</figcaption></figure>

**Abbreviations:** EMG = electromyogram; FC = forearm circumference; GS = grip strength; ICP = intra compartmental pressure; MYO = myotonometry.

–Pritchard et al. [32] used resting pressure >6 mmHg, and a rise of pressure (usually doubling the resting pressure) that should be maintained for several minutes.

–Other authors such as Barrera-Ochoa et al. [20] recommended lowering the ICP thresholds to >1.5 mmHg at rest, 13 mmHg at 1 min, and >12.5 mmHg at 5 min.

## 4. Discussion

Chronic Exertional Compartment Syndrome of the forearm is a rare condition with imprecisely defined diagnostic criteria. This systematic review aimed to provide a comprehensive overview of the current diagnostic methods.

ICP measurement is still considered the gold standard method for the
<figure><img src="image_5.png" /><figcaption>Fig. 3. Mean ICP measurement according to the studies.</figcaption></figure>

Red dots: resting pressure, yellow dots: immediately after exercise, green dots: at 1 min after exercise, blue dots: at 5 min after exercise; (v) = volar compartment, (d) = dorsal compartment).

CECS diagnosis, despite substantial variations among studies. Yet, the validity of this measurement has been questioned by several authors in recent reviews on CECS of the leg [41–43]. Roberts and Franklyn-Miller [49] reported variation of intramuscular pressure among healthy individuals between 23 mmHg and 66 mmHg, and Roscoe et al. [41] reported pressures ranging from 42 to 150 mmHg during exercise in CECS patients, and from 28 to 141 mmHg in controls.

In this review, we pointed out mean pressure values ranging from 17 mmHg to 144 mmHg for CECS subjects, when assessed immediately after exercise, with a clear lack of uniformity among measurement protocols, including exercise duration, ranging from 2 to 60 min, and inconsistent catheter positioning [9, 13, 20, 28]. The time of measurement also varied widely, with 4 studies monitoring pressure during exercise [9, 29, 36, 38] that could be elevated six times the baseline pressure [44], while internal factors could explain some of the observed variations such as morphological factors, sex, involved compartments [45], or level of training [46].

Catheter positioning has also been described as one of the key confounding factors. Roberts and Franklyn-Miller [49] reported in their review that the depth of the catheter extremity could induce variation of ICP up to 50% if placed more superficially in the anterior compartment of the leg. They also reported a great variation in catheter angle, which corroborates our findings with positioning ranging from 30° to 45° [9, 13, 20, 28]. Forearm positioning is another important parameter, as variations of ICP have been described because of inconsistent positioning [45]. While there existed few studies describing patient and catheter positioning [2, 9, 10, 13, 26, 31], a frequent practice was to have the forearm placed on a table in the pronation position with the elbow held at 90° to measure the extensor compartment, and to have the forearm in the supination position with the elbow fully extended to measure the flexor compartment, with the catheter positioned at 45°.

The standardization of the measurement equipment is another issue.

Boody [47] observed variations in measurements among different devices. This is complicated by the fact, that the Stryker device, which was the most commonly used in the studies of this review, is no longer available in Europe. To our knowledge, no existing data favors any device, but the Whiteside method which has a notable standard-error and a lack of precision, appears to be the less suitable for clinical practice [48].

Most times of measurement were related to the Pedowitz criteria, with ICP measured at rest, then at 1 and 5 min after exercise. Four studies reported ICP measured during the exercise protocol [9, 29, 36, 38]. However, dynamic ICP measurement on the lower limb has been debated due to confounding factors such as velocity, inclined or loaded walking, or negative heel running shoes [49]. Previously, Pedowitz and Toutounghi [39] also reported that dynamic pressure magnitude could be affected by catheter depth and muscle contraction intensity. The main interest of the technique is that it allows matching ICP changes to symptoms occurrences. Interestingly, it is important to note that pain intensity and the degree of intra-compartmental pressure might be correlated. Indeed, one study concerning 138 patients reported no correlation with the visual analogue scale and the degree of ICP (p = 0.76), but found a moderate significant correlation with the verbal rating scale (r = 0.497, p = 0.01) [50].

Measuring the time required for pressure normalization could be an appropriate alternative. García-Mata [10] found a mean time of 35 min before pressure normalization. However, 35 min could be long to be used in clinical practice due to time constraints. Barrera-Ochoa et al. [2], reported a sensitivity of 100%, and a specificity of 94.7% for this measure using fasciotomy as the gold standard and setting a cut-off time of 14.5 min. Yet, their study had several limitations, due to the absence of a control group, and an inherent bias related to the use of fasciotomy as reference, such as a lack of blinding, and a potential spectrum bias. Even if these findings provide valuable insights, more studies are needed to validate them.
<table><caption>**Table 4**
Intra-compartmental pressure measurement thresholds.</caption><thead><tr><th>Studies</th><th>Mean resting pressure<br>mmHg (range)</th><th>Mean post-exercise pressure<br>mmHg (range)</th><th>Mean pressure change<br>mmHg (between<br>Resting and post<br>exercise pressure)</th><th>Mean<br>pressure<br>change %</th><th>ICP threshold criteria</th></tr></thead><tbody><tr><td>O'Dowd et al.<br>[13]</td><td>11.7 mmHg<br>(7–28 mmHg)</td><td>30.5 mmHg (15–45 mmHg)<br>immediately after exercise<br>32.2 mmHg (25–41 mmHg)<br>immediately after exercise.</td><td>18.8 mmHg</td><td>261</td><td>NS<br>Recommendation of lowering the ICP thresholds to<br>Prest > 1.5 mmHg, P1min > 13 mmHg, and<br>P5 min > 12.5 mmHg.</td></tr><tr><td>Barrera-Ochoa<br>et al. [2]</td><td>6.9 mmHg<br>(1–14 mmHg)</td><td>P1min 23.9 mmHg<br>(18–30 mmHg)<br>P5 min 20.1 mmHg<br>(18–26 mmHg)</td><td>25.3 mmHg</td><td>268</td><td>And setting Trest to > 14.5 min</td></tr><tr><td>García-Mata [10]</td><td>21.6 mmHg</td><td>Mean pressure time<br>normalization = 35 min</td><td>NS</td><td>NS</td><td>>10 mmHg pressure at rest, >20 mmHg 1 min<br>after exertion, >20 mmHg after 5' as abnormal ICP<br>values, and >15' as maximum ICP normalization<br>time after exertion</td></tr><tr><td>Brown et al. [26]</td><td>NS</td><td>Mean post exercise pressure<br>58 mmHg immediately after<br>exercise</td><td>NS</td><td>NS</td><td>Threshold for abnormality of 30 mmHg</td></tr><tr><td>Pritchard et al.<br>[32]</td><td>9.0 mmHg</td><td>17.0 mmHg</td><td>8.0 mmHg</td><td>212</td><td>Resting pressure >6 mmHg and, after the specified<br>2 min gripping exercise, should rise further<br>(usually doubling the resting pressure) and be<br>maintained for several minutes.</td></tr><tr><td>Guerzider et al.<br>[15]</td><td>NS</td><td>NS</td><td>NS</td><td>NS</td><td>Pedowitz criteria: base pressure >15 mmHg,<br>pressure after 1 min of exercise >30 mmHg,<br>pressure 10 min after exercise completion<br>>20 mmHg</td></tr><tr><td>Gondolini et al.<br>[18]</td><td>9.3 mmHg ± 3.7<br>(range 2–16)</td><td>30.5 mmHg ± 7.5 (range<br>24–37) 1 min after exercise.<br>22.6 mmHg ± 6.1 (range<br>18–26) 5 min after exercise</td><td>21.2 mmHg</td><td>227</td><td>Pedowitz criteria</td></tr><tr><td>Schiavi et al. [17]</td><td>Volar compartment<br>8.3 mmHg</td><td>1 min after exercise:<br>Volar compartment 31 mmHg<br>Dorsal compartment 28 mmHg<br>5 min after exercise:<br>Volar compartment 21.4 mmHg<br>Dorsal compartment 17.5 mmHg<br>Pmax 32.3 ± 3.7 mmHg</td><td>NA</td><td>NA</td><td>Pedowitz criteria</td></tr><tr><td>Barrera et al. [20]</td><td>Prest 7.1 ± 3.9 mmHg</td><td>P1min 7.1 ± 3.2 mmHg<br>P5 min 21.3 ± 3.5 mmHg<br>T rest 19.7 ± 3.1 min<br>47.3 mmHg volar</td><td>25.2 mmHg</td><td>281%</td><td>Pedowitz criteria</td></tr><tr><td>Harrison et al.<br>[23]</td><td>10.4 mmHg volar<br>10.8 mmHg dorsal at<br>rest</td><td>40.4 mmHg dorsal on exertion.<br>Immediately after exercise<br>pressures 35 ± 9 mmHg (range,<br>20–52 mmHg)<br>1-min 29 ± 10 mmHg (range,<br>10–45 mmHg)<br>5-min time points 25 ± 7 mmHg<br>(range, 10–38 mmHg)</td><td>NA</td><td>NA</td><td>Pedowitz criteria accepting a rise of 10 mmHg<br>with exertion regardless of baseline</td></tr><tr><td>Winkes et al. [9]</td><td>15.0 ± 4 mmHg</td><td>1-min 29 ± 10 mmHg (range,<br>10–45 mmHg)<br>5-min time points 25 ± 7 mmHg<br>(range, 10–38 mmHg)</td><td>20.0 mmHg</td><td>230%</td><td>>10 mmHg in rest and >20 mmHg 1 and 5 min<br>after provocation</td></tr><tr><td>Croutzet et al.<br>[29]</td><td>NS</td><td>NS</td><td>NA</td><td>NA</td><td>Over 30 mmHg during effort</td></tr><tr><td>Zandi [33]</td><td>NS</td><td>Mean post exercise pressure:<br>51.8 mmHg<br>After 5 or 10 min rest:<br>35.6 mmHg</td><td>NA</td><td>NA</td><td>Pedowitz criteria</td></tr><tr><td>Hijjawi et al. [27]</td><td>NS</td><td>Post exercise pressure:<br>28.0 mmHg</td><td>NA</td><td>NA</td><td>Pedowitz criteria</td></tr><tr><td>Gielen et al. [28]</td><td>15.8 mmHg</td><td>Post exercise pressure:<br>41.4 mmHg</td><td>25.6 mmHg</td><td>260%</td><td>Pedowitz criteria</td></tr><tr><td>Pegoli et al. [21]</td><td>11.5 mmHg</td><td>Post exercise pressure:<br>34.5 mmHg<br>At 5 min rest: 25.7<br>10.0 mmHg at 3 min post<br>exercise<br>30.0 mmHg at 5 min post-<br>exercise</td><td>23.0 mmHg</td><td>300%</td><td>Pedowitz criteria</td></tr><tr><td>Cole et al. [19]</td><td>15.0 mmHg</td><td>40.0 mmHg immediately after<br>exercise<br>36.0 mmHg at 1 min after<br>exercise</td><td>-5.0 mmHg</td><td>66%</td><td>Pedowitz criteria</td></tr><tr><td>Winkes et al. [22]</td><td>16.0 mmHg</td><td>40.0 mmHg immediately after<br>exercise<br>36.0 mmHg at 1 min after<br>exercise</td><td>24.0 mmHg</td><td>250%</td><td>>10 mmHg in rest and >20 mmHg 1 and 5 min<br>after provocation</td></tr></tbody></table>

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<table><caption>**Table 4 (continued)**</caption><thead><tr><th>Studies</th><th>Mean resting pressure<br>mmHg (range)</th><th>Mean post-exercise pressure<br>mmHg (range)</th><th>Mean pressure change<br>mmHg (between<br>Resting and post<br>exercise pressure)</th><th>Mean<br>pressure<br>change %</th><th>ICP threshold criteria</th></tr></thead><tbody><tr><td>O'hEireamhoin<br>et al. [25]</td><td>20.0 mmHg</td><td>35.0 mmHg at 5 min after<br>exercise<br>NS</td><td>NA</td><td>NA</td><td>Pedowitz criteria</td></tr><tr><td>Wasilewski and<br>Asdourian [37]</td><td>25.0 mmHg in the<br>right forearm and<br>31 mmHg in the left<br>forearm.</td><td>46.0 mmHg in the right forearm<br>and 36.0 mmHg in the left<br>forearm</td><td>13.0 mmHg</td><td>146%</td><td>Resting pressure >15 mmHg,<br>After exercise return to pre-exercise values >2 min</td></tr><tr><td>Allen and Barnes<br>[38]</td><td>10.0 mmHg</td><td>NS</td><td>NA</td><td>NA</td><td>NS</td></tr><tr><td>Goubier and<br>Saillant [34]</td><td>17.5 mmHg</td><td>30.5 mmHg after exercise<br>27.2 mmHg 15 min after<br>exercise<br>17.5 mmHg 30 min after<br>exercise</td><td>13.0 mmHg</td><td>174%</td><td>Pedowitz criteria</td></tr><tr><td>Kutz et al. [40]</td><td>23.0 mmHg</td><td>42.5 mmHg</td><td>19.5 mmHg</td><td>184%</td><td>NS<br>Intramuscular pressure of greater than or equal to<br>15 mmHg and/or a 5-min post-exercise pressure of<br>greater than or equal to 25 mmHg consistent with<br>a diagnosis of chronic exertional compartment<br>syndrome</td></tr><tr><td>Pedowitz and<br>Toutounghi<br>[39]</td><td>6.0 mmHg</td><td>32.0 mmHg</td><td>26.0 mmHg</td><td>530%</td><td>Pedowitz criteria<br>Pedowitz criteria</td></tr><tr><td>Söderberg [36]</td><td>23.3 mmHg</td><td>125.3 mmHg</td><td>102.0 mmHg</td><td>530%</td><td>Pedowitz criteria</td></tr><tr><td>Hider et al. [35]</td><td>33.0 mmHg</td><td>144.0 mmHg</td><td>111.0 mmHg</td><td>436%</td><td>Pedowitz criteria</td></tr></tbody></table>

**Abbreviations:** NS: not specified; NA: not applicable; mmHg = millimeters of mercury; ICP = intra compartmental pressure; Prest = pressure at rest; Pmax = pressure immediately after exercise; P1min = pressure at 1 min after exercise; P5 min = pressure at 5 min after exercise; Trest = time between pressure immediately after exercise and return to baseline.

We also reported that 47% of the studies did not meet the Pedowitz criteria when measurements were taken at rest, and 75% at 1 min after exercise. Additionally, the Whitesides and Heckman criteria were not met in 75% of the cases at 5 min after exercise. The threshold of 30 mmHg, as selected by Brown et al. [26], and Croutzet et al. [29] was reached in a larger proportion (90% of studies) within this review. Furthermore, the 20-mmHg cut-off at 5 min post-exercise, was reached in 85% of the studies. Barrera-Ochoa et al. observed that, out of 124 patients in their study, only 2 had values exceeding 30 mmHg at 1 min, while 30 patients surpassed the 20 mmHg threshold at 5 min [2]. Due to the few available researches on physiological forearm ICP measurement, and the low number of patients, caution should be paid when comparing existing data, as it has been done by Aweid et al. for the leg [43]. Nevertheless, in the study by Ardolino et al. [45] with physiological post exercise ICP measured up to 24 mmHg in the extensor compartment, and 19 mmHg in the flexor compartment, no overlap existed with the 30-mmHg threshold. Yet, Schoeffl et al. [51] reported that 3 out of 10 healthy climbers of their series had pressure rising above the 30-mmHg threshold. Due to the poor quality of evidence of the studies, no conclusion can be drawn on the threshold to be used in clinical practice. However, taking into account this review and our clinical experience, we could advise the use of a 30-mmHg threshold, combined with a 5-min-post-exercise 20-mmHg threshold in patients with compatible clinical history and symptoms.

Magnetic resonance imaging has raised some interest as a promising diagnostic tool for CECS diagnosis because of its high sensitivity. One potential pathophysiological mechanism of CECS involves a reduction in tissue perfusion leading to low-level ischemia, coupled with an increased pressure within the muscular fascia [52,53]. Muscles will then develop edema, resulting in an increase of signal intensity in T2-weighted sequences [14]. Ritchie et al. [7] reported a sensitivity of 96% and a specificity of 88% for post exercise MRI compared to ICP measurement in diagnosing CECS of the leg. Additionally, MRI's ability to rule out differential diagnoses such as compressive neuropathies, tendonitis, muscle tear [10,14], adds to its diagnostic value. However, a concern arises regarding potential overtreatment, if MRI is used as the sole diagnostic method, due to its lower specificity. Gielen et al. [28] and

Jans et al. [24] reported an increase in signal intensity after exercise in both healthy untrained individuals and asymptomatic patients who underwent fasciotomy. Moreover, the lack of uniformity in the sequences used, with some authors reporting the use of T1-weighted sequences, presents a limitation of the comparability between studies, and highlights the need for caution in interpreting findings through studies. Similarly to findings in CECS of the leg [7], the limited number of studies with high methodological quality, the absence of a control group and the small size of the studied populations do not currently support the replacement of the ICP measurement by MRI as a primary diagnostic method for CECS at this stage. Further research is needed to better establish MRI diagnostic utility.

Non-invasive explorations, clinical (grip strength [13], forearm circumference [30]) or non-clinical (electromyography [31,40], myotonometry [31]), are of interest in this context because of their ease of use, and their benefit compared to ICP that can be a long and uncomfortable procedure for the patients. However, the limited number of studies and their low level of evidence prevent conclusions regarding their practical utility. Notably, no significant relationship with ICP was found for grip strength measurement [13]. The observed 0.4 cm difference in forearm circumference may be attributed to measurement error [30]; and the relatively low correlation coefficient of 0.47 for myotonometry suggested caution in establishing association with ICP [31]. Other non-invasive explorations have been described for the diagnosis of CECS of the leg but they have not been studied for the forearm yet. For example, near infrared spectroscopy has been reported a useful tool [7], with an increase in muscle reoxygenation time after exercise in CECS patients (anterior compartment) compared to control subjects. Single photon emission tomography has also been used, but with mixed results and heterogeneity among studies, and could be less useful for the diagnosis CECS [54]. Previously, one study reported interesting results to diagnose CECS by laser doppler flowmetry [55], but presently no other research on the subject seems to have been published.

History and clinical presentation are of key importance in the diagnosis of CECS, given the variability of para-clinical criteria. This review emphasizes that clinical parameters should remain the precondition for further investigations. Piasecki et al. [30] have argued that pressure
measurement was not a necessary condition for the decision to undergo surgery. Despite its importance, there are currently no forearm studies investigating the clinical factors predictive of CECS, unlike for the CECS of the leg which reported muscle hardness with an odds ratio of 2.18 (p < 0.001) and muscle hernia after exercise with an odds ratio of 1.44 (p < 0.01), with sensitivity and specificity evaluated at 75% and 98%, respectively [56,57]. Similar research for forearm CECS would be of interest.

## 4.1. Limitations

This review has several limitations. Firstly, the limited availability of high-quality evidence studies, and the few diagnostic studies with a control group, prevented us to provide strong conclusions. Secondly the considerable variability of the exercises and the measurement protocols makes it difficult to compare studies. Thirdly, there is a lack of reference for assessing the diagnostic performance of the different methods. We did note use fasciotomy as gold standard to avoid misleading. Therefore, we could not perform a meta-analysis, due to the heterogeneity of the protocols and the limited quality of several studies.

## 5. Conclusion

Multiple methods are available for the diagnosis of the forearm CECS: ICP measurement, MRI, EMG, Myotonometry, Grip Strength and Forearm circumference. While the existing data do not provide sufficient evidence to favor an alternative diagnostic method over ICP measurement, Pedowitz criteria or Whitesides and Heckman criteria should be used cautiously for the diagnosis of CECS of the forearm given their absence of formal validation. More studies are needed to assess the relevance of measuring the pressure normalization time, and to determine more accurate ICP thresholds. Non-invasive methods such as surface electromyography, grip strength and myotonometry might also be relevant to a lesser extent, and easier to use, but must also be the subject of further research before having a clinical application.

## Author's contributions

Dr Fouasson-Chailloux: conceptualization, methodology, writing – original draft.

Dr Hirardot: formal analysis, methodology, writing – original draft.

Dr Dauty: supervision, writing – review & editing.

Dr Pomares: validation, writing – review & editing.

Dr Grondin: validation, writing – review & editing.

Dr Menu: validation, writing – review & editing.

## Funding sources

This research did not receive any specific grant.

## Conflict of interest

The authors declare that they have no conflicts of interest.

## Declaration of generative AI and AI-assisted technologies in the writing process

None.

## Acknowledgement

None.

## References

[1] Regas I, Pluvy I, Sakek F, Tuphe P, Ortega P, Guinchard B, et al. Epidemiology of upper limb chronic exertional compartment syndrome (CECS) in the French Motorcycle Federation racers: results of a national questionnaire-based study. Hand Surg Rehabil 2021;40:268-76. https://doi.org/10.1016/j.hansur.2020.12.017.

[2] Barrera-Ochoa S, Correa-Vazquez E, Gallardo-Calero I, Haddad S, Sallent A, Soldado F, et al. TRest as a new diagnostic variable for chronic exertional compartment syndrome of the forearm: a prospective cohort analysis of 124 athletes. Clin J Sport Med 2018;28:516-23. https://doi.org/10.1097/JSM.0000000000000482.

[3] Raphael BS, Paletta GA, Shin SS. Chronic exertional compartment syndrome of the forearm in a major league baseball pitcher. Am J Sports Med 2011;39:2242-4. https://doi.org/10.1177/0363546511417171.

[4] Abe Y, Fujii K. Chronic compartment syndrome of the mobile wad: a case report. J Hand Surg Asian Pac Vol 2017;22:516-8. https://doi.org/10.1142/S0218810417720364.

[5] Humpherys J, Lum Z, Cohen J. Diagnosis and treatment of chronic exertional compartment syndrome of the forearm in motocross riders. JBJS Rev 2018;6. https://doi.org/10.2106/JBJS.RVW.17.00023. e3-e3.

[6] Smeraglia F, Tamborini F, Garutti L, Minini A, Basso MA, Cherubino M. Chronic exertional compartment syndrome of the forearm: a systematic review. EFORT Open Rev 2021;6:101-6. https://doi.org/10.1302/2058-5241.6.200107.

[7] Ritchie ED, Vogels S, van Dongen TTCF, van der Burg BLSB, Scheltinga MRM, Zimmermann WO, et al. Systematic review of innovative diagnostic tests for chronic exertional compartment syndrome. Int J Sports Med 2023;44:20-8. https://doi.org/10.1055/a-1866-5957.

[8] Pedowitz RA, Hargens AR, Mubarak SJ, Gershuni DH. Modified criteria for the objective diagnosis of chronic compartment syndrome of the leg. Am J Sports Med 1990;18:35-40. https://doi.org/10.1177/036354659001800106.

[9] Winkes MB, Luiten EJT, van Zoest WJF, Sala HA, Hoogeveen AR, Scheltinga MR. Long-term results of surgical decompression of chronic exertional compartment syndrome of the forearm in motocross racers. Am J Sports Med 2012;40:452-8. https://doi.org/10.1177/0363546511425647.

[10] García-Mata S. Chronic exertional compartment syndrome of the forearm in adolescents. J Pediatr Orthop 2013;33:832-7. https://doi.org/10.1097/BPO.0b013e3182a0078b.

[11] Page MJ, Moher D, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, et al. PRISMA 2020 explanation and elaboration: updated guidance and exemplars for reporting systematic reviews. BMJ 2021;1:n160. https://doi.org/10.1136/bmj.n160.

[12] Guyatt GH, Oxman AD, Vist GE, Kunz R, Falck-Ytter Y, Alonso-Coello P, et al. GRADE: an emerging consensus on rating quality of evidence and strength of recommendations. BMJ 2008;336:924-6. https://doi.org/10.1136/bmj.39489.470347.AD.

[13] O'Dowd DP, Romer H, Hughes R, Harding N, Ball S, Migliorini F, et al. Forearm compartment pressures and grip strength in elite motorbike racers with chronic exertional compartment syndrome. J Orthop Surg Res 2021;16:603. https://doi.org/10.1186/s13018-021-02765-z.

[14] Badenhorst J, Velleman M, van Rensburg AJ, Botha T, van der Walt N, van Rensburg CJ. MRI findings in chronic exertional compartment syndrome of the forearm: using signal intensity ratio as a diagnostic tool. SA J Radiol 2021;25. https://doi.org/10.4102/sajr.v25i1.2219.

[15] Guerzider Regas I, Pluvy I, Tuphe P, Sakek F, Fuchs B, Haight H, et al. Long term functional outcomes after minimally invasive surgical decompression in upper limb chronic exertional compartment syndrome in 30 patients. Hand Surg Rehabil 2021; 40:32-9. https://doi.org/10.1016/j.hansur.2020.09.006.

[16] Tominaga A, Shimada K, Temporin K, Noguchi R. Post-exertional MRI is useful as a tool for diagnosis and treatment evaluation for chronic exertional compartment syndrome of forearms. J Hand Surg Asian Pac Vol 2019;24:311-6. https://doi.org/10.1142/S2424835519500395.

[17] Schiavi P, Gondolini G, Gandolfi CE, Guardoli L, Vaienti E, Zasa M. Mini-open surgical fasciotomy for chronic exertional compartment syndrome of the forearm in professional motorcycling adolescents. Clin J Sport Med 2020;30(6):e225-30. https://doi.org/10.1097/JSM.0000000000000700.

[18] Gondolini G, Schiavi P, Pogliacomi F, Ceccarelli F, Antonetti T, Zasa M. Long-term outcome of mini-open surgical decompression for chronic exertional compartment syndrome of the forearm in professional motorcycling riders. Clin J Sport Med 2019;29(6):476-81. https://doi.org/10.1097/JSM.0000000000000539.

[19] Cole A, Hiatt JL, Arnold C, Sites T, Ylanon R. Chronic exertional compartment syndrome in the forearm of a collegiate softball pitcher. Sports Med Open 2017;3: 11. https://doi.org/10.1186/s40798-017-0080-5.

[20] Barrera-Ochoa S, Haddad S, Correa-Vazquez E, Segura JF, Gil E, Lluch A, et al. Surgical decompression of exertional compartment syndrome of the forearm in professional motorcycling racers: comparative long-term results of wide-open versus mini-open fasciotomy. Clin J Sport Med 2016;26.

[21] Pegoli L, Pozzi A, Pivato G. Endoscopic single approach forearm fasciotomy for chronic exertional compartment syndrome: long term follow-up. J Hand Surg Asian Pac Vol 2016;21:8-12. https://doi.org/10.1142/S2424835516400026.

[22] Winkes MB, Teijink JA, Scheltinga MR. Motorcycle racer with unilateral forearm flexor and extensor chronic exertional compartment syndrome. BMJ Case Rep 2016;2016:10.1136/bcr-2016-214739. https://doi.org/10.1136/bcr-2016-214739.

[23] Harrison JWK, Thomas P, Aster A, Wilkes G, Hayton MJ. Chronic exertional compartment syndrome of the forearm in elite rowers: a technique for mini-open
[24] fasciotomy and a report of six cases. Hand (N Y) 2013;8:450-3. https://doi.org/
10.1007/s11552-013-9543-4.

[24] Jans C, Peersman G, Peersman B, Van Den Langenbergh T, Valk J, Richard T. Endoscopic decompression for chronic compartment syndrome of the forearm in motocross racers. Knee Surg Sports Traumatol Arthrosc 2015;23:2522-7. https://doi.org/10.1007/s00167-014-3044-z.

[25] O'hEireamhoin S, Baker JF, Neligan M. Chronic exertional compartment syndrome of the forearm in an elite rower. Case Rep Orthop 2011;2011:1-2. https://doi.org/10.1155/2011/497854.

[26] Brown JS, Wheeler PC, Boyd KT, Barnes MR, Allen MJ. Chronic exertional compartment syndrome of the forearm: a case series of 12 patients treated with fasciotomy. J Hand Surg Eur Vol 2011;36:413-9. https://doi.org/10.1177/1753193410397900.

[27] Hijjawi J, Nagle DJ. Endoscopic-assisted fascial decompression for forearm exertional compartment syndrome: a case report and review of the literature. Hand (N Y) 2010;5:427-9. https://doi.org/10.1007/s11552-010-9261-0.

[28] Gielen JL, Peersman B, Peersman G, Roelant E, Van Dyck P, Vanhoenacker F, et al. Chronic exertional compartment syndrome of the forearm in motocross racers: findings on MRI. Skeletal Radiol 2009;38:1153-61. https://doi.org/10.1007/s00256-009-0746-2.

[29] Croutzet P, Chassat R, Masmejean EH. Mini-invasive surgery for chronic exertional compartment syndrome of the forearm: a new technique. Tech Hand Up Extrem Surg 2009;13:137-40. https://doi.org/10.1097/BTH.0b013e3181aa9193.

[30] Piasecki DP, Meyer D, Bernard RB. Exertional compartment syndrome of the forearm in an elite flatwater sprint kayaker. Am J Sports Med 2008;36:2222-5. https://doi.org/10.1177/0363546508324693.

[31] Korhonen RK, Vain A, Vanninen E, Viir R, Jurvelin JS. Can mechanical myotonometry or electromyography be used for the prediction of intramuscular pressure? Physiol Meas 2005;26:951-63. https://doi.org/10.1088/0967-3334/26/6/006.

[32] Pritchard MH, Williams RL, Heath JP. Chronic compartment syndrome, an important cause of work-related upper limb disorder. Rheumatology 2005;44:1442-6. https://doi.org/10.1093/rheumatology/kei037.

[33] Zandi H. Results of compartment decompression in chronic forearm compartment syndrome: six case presentations. Br J Sports Med 2005;39. https://doi.org/10.1136/bjsm.2004.012518. e35-e35.

[34] Goubier JN, Saillant G. Chronic compartment syndrome of the forearm in competitive motor cyclists: a report of two cases. Br J Sports Med 2003;37(5):452-3. discussion 453-4. doi: 10.1136/bjsm.37.5.452.

[35] Hider SL, Hilton RC, Hutchinson C. Chronic exertional compartment syndrome as a cause of bilateral forearm pain. Arthritis Rheum 2002;46:2245-6. https://doi.org/10.1002/art.10437.

[36] Söderberg TA. Bilateral chronic compartment syndrome in the forearm and the hand. J Bone Joint Surg Br 1996;78:780-2.

[37] Wasilewski SA, Asdourian PL. Bilateral chronic exertional compartment syndromes of forearm in an adolescent athlete: case report and review of literature. Am J Sports Med 1991;19:665-7. https://doi.org/10.1177/036354659101900620.

[38] Allen MJ, Barnes MR. Muscles in the forearm: a case report. n.d.

[39] Pedowitz RA, Toutoughi FM. Chronic exertional compartment syndrome of the forearm flexor muscles. J Hand Surg Am 1988;13:694-6. https://doi.org/10.1016/S0363-5023(88)80126-6.

[40] Kutz JE, Singer R, Lindsay M. Chronic exertional compartment syndrome of the forearm: a case report. J Hand Surg 1985;10:302-4. https://doi.org/10.1016/S0363-5023(85)80130-1.

[41] Roscoe D, Roberts AJ, Hulse D. Intramuscular compartment pressure measurement in chronic exertional compartment syndrome: new and improved diagnostic criteria. Am J Sports Med 2015;43:392-8. https://doi.org/10.1177/0363546154555970.

[42] Tiidus PM. Is intramuscular pressure a valid diagnostic criterion for chronic exertional compartment syndrome? Clin J Sport Med 2014;24:87-8. https://doi.org/10.1097/JSM.0000000000000065.

[43] Aweid O, Del Buono A, Malliaras P, Iqbal H, Morrissey D, Maffulli N, et al. Systematic review and recommendations for intracompartmental pressure monitoring in diagnosing chronic exertional compartment syndrome of the leg. Clin J Sport Med 2012;22:356-70. https://doi.org/10.1097/JSM.0b013e3182580e1d.

[44] Rydholm U, Werner CO, Ohlin P. Intracompartmental forearm pressure during rest and exercise. Clin Orthop Relat Res 1983;(175):213-5. https://doi.org/10.1097/00003086-198305000-00034.

[45] Ardolino A, Zeineh N, O'Connor D. Experimental study of forearm compartmental pressures. J Hand Surg 2010;35:1620-5. https://doi.org/10.1016/j.jhsa.2010.06.017.

[46] Ferguson RA, Brown MD. Arterial blood pressure and forearm vascular conductance responses to sustained and rhythmic isometric exercise and arterial occlusion in trained rock climbers and untrained sedentary subjects. Eur J Appl Physiol 1997;76:174-80. https://doi.org/10.1007/s004210050231.

[47] Boody AR. Accuracy in the measurement of compartment pressures: a comparison of three commonly used devices. J Bone Joint Surg Am 2005;87:2415. https://doi.org/10.2106/JBSJ.D.02826.

[48] Whitesides TE, Haney TC, Harada H, Holmes HE, Morimoto K. A simple method for tissue pressure determination. Arch Surg 1975;110:1311-3.

[49] Roberts A, Franklyn-Miller A. The validity of the diagnostic criteria used in chronic exertional compartment syndrome: a systematic review. Scand Med Sci Sports 2012;22:585-95. https://doi.org/10.1111/j.1600-0838.2011.01386.x.

[50] Tam JPH, Gibson AGF, Murray JRD, Hassaballa M. Fasciotomy for chronic exertional compartment syndrome of the leg: clinical outcome in a large retrospective cohort. Eur J Orthop Surg Traumatol 2019;29:479-85. https://doi.org/10.1007/s00590-018-2299-3.

[51] Schoeffl V. Evaluation of physiological standard pressures of the forearm flexor muscles during sport specific ergometry in sport climbers. Br J Sports Med 2004; 38:422-5. https://doi.org/10.1136/bjsm.2002.003996.

[52] Liu B, Barrazueta G, Ruchelsman DE. Chronic exertional compartment syndrome in athletes. J Hand Surg 2017;42:917-23. https://doi.org/10.1016/j.jhsa.2017.09.009.

[53] Mohler LR, Styf JR, Pedowitz RA, Hargens AR, Gershuni DH. Intramuscular deoxygenation during exercise in patients who have chronic anterior compartment syndrome of the leg. J Bone Joint Surg Am 1997;79:844-9. https://doi.org/10.2106/00004623-199706000-00007.

[54] Oturai PS, Lorenzen T, Nørregaard J, Simonsen L. Evaluation of Tc-99m-tetrofosmin single-photon emission computed tomography for detection of chronic exertional compartment syndrome of the leg. Scand Med Sci Sports 2006;16:282-6. https://doi.org/10.1111/j.1600-0838.2005.00460.x.

[55] Abraham P, Leftheriotis G, Saumet JL. Laser Doppler flowmetry in the diagnosis of chronic compartment syndrome. J Bone Joint Surg Br 1998;80:365-9.

[56] Vignaud E, Menu P, Eude Y, Maugars Y, Dauty M, Fouasson-Chailloux A. A comparison of two models predicting the presence of chronic exertional compartment syndrome. Int J Sports Med 2021;42:1027-34. https://doi.org/10.1055/a-1342-8209.

[57] Fouasson-Chailloux A, Menu P, Allorent J, Dauty M. Determination of the predictive clinical parameters to diagnose chronic exertional compartment syndrome. Eur J Sport Sci 2018;18:279-85. https://doi.org/10.1080/17461391.2017.1405078.