Non-invasive Measurement of Compartment Pressure: Reliability

Study Overview
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Brief Summary
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The investigators want to investigate the reliability (variability) of a new device, that should be able to measure lower leg compartment pressure non-invasively. Therefore the tool is used under different circumstances. The introduced differences in circumstances are: Measurements at several time points Measurements using different anatomical landmarks Measurements by different researchers Measurements in rest and after exercise This study's results are important to create a reliable measurement tools for patients with lower leg symptoms. In this way the diagnosis can be improved and as well the treatments given to the patients. It is expected that the variability of the device will be low compared to current techniques.

Detailed Description
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Chronic Exertional Compartment Syndrome (CECS) is one of the exercise-induced lower leg pathologies. Recognition by patients and physicians is not optimal. As a consequence, many patients are undiagnosed and are forced to stop their sporting activities. To diagnose CECS, a doctor should be alerted by a patient's history and a physical examination. If both suggestive of CECS, an invasive intra compartmental pressure measurement (ICPM) in the affected compartment may be performed. During the ICPM a catheter is placed into the muscle via a hollow needle. The ICPM is not flawless in terms of accuracy and reproducibility and has a low intra-observer reproducibility. Moreover, haematoma or other tissue damage may occur following an ICPM. Nevertheless, this invasive ICPM is in 2022 still considered the 'gold-standard' diagnostic tool for CECS, in the absence of a better one. A novel non-invasive tool for CECS is possibly provided by measuring muscle tissue compressibility. The idea is, that muscle tissue with a high pressure (as in CECS patients) requires more external force to compress, compared to tissue with a low pressure. The study device used in this study, the CPM#1 device, is based on this principle. The CPM#1 device is non-invasive, not painful, very user friendly, and the measurement can be executed as an 'office procedure' in a couple of minutes. This study will focus on determining the reliability of the device in healthy volunteers. The primary objective is - To validate the inter-observer reliability of compressibility measurements with the CPM#1 device during rest in healthy volunteers. Secondary objectives are To validate the intra-observer reliability of compressibility measurements with the CPM#1 device during rest in healthy volunteers. To investigate the effect of exercise on compressibility immediately, one minute, and five minutes after exercise in healthy volunteers. To map the invasiveness of the compressibility measurement with the CPM#1 device. Nature and extent of the burden and risks associated with participation, benefit and group relatedness: Healthy subjects will undergo several compressibility measurements, both before and after a treadmill exercise. They will also complete a NIAPS (Netwerk Inspannings Afhankelijke PijnSyndromen) questionnaire and an 'experience' questionnaire. The harm associated with the CPM#1 device is none. However, the subjects will not benefit from this study

Official Title
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Validation of CPM#1 Compressibility in Healthy Volunteers in Rest and After Exercise

Conditions
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CEC Syndrome

Intervention / Treatment
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* Device: Compremium Compressibility Measurement
* Procedure: Treadmill Running
* Other: Questionnaire


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ≥ 18 years Proficient in speaking and reading Dutch Exclusion Criteria: Presence of complaints suggestive of CECS, previously diagnosed with CECS or previous positive ICPM History of surgery or other trauma which penetrated the fascia of the leg Other concurrent limb pathologies or anomalies amongst others: Peripheral arterial or venous disease Muscle disorders, diabetes mellitus, peripheral neuropathies Unable to exercise for five minutes Open wound or painful bruise less than one week ago at site of measurement

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Intervention Model: Single Group Assignment
Interventional Model Description: A performance validation pilot of the CPM#1 device in healthy volunteers. There will only be one study arm, no comparator, and no randomization.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Healthy Volunteers<br>Healthy subjects are not subjected to any type of treatment besides non-invasive lower leg muscle compressibility measurements in rest and after exercise. All 35 healthy subjects will undergo four times four measurements in rest (m. tibialis anterior of both legs, using two different internal landmarks). These four times four measurements in rest will each be done by three observers. To measure the effect of exercise, compressibility will be measured immediately, one minute, and five minutes after a standard treadmill exercise at just one leg. The treadmill exercise and the corresponding measurements will be performed twice to address for measurements of both legs. | Device: Compremium Compressibility Measurement<br>* CPM#1 measurements: Step 1: Manual investigation to identify the compartment for compressibility measurements Step 2: Marking the location for compressibility measurements Step 3 - Examination with CPM#1 Place the probe on the target area Identify correct landmark Compress the compartment Increase steadily the pressure applied by the CP probe to 80 mmHg.<br>Procedure: Treadmill Running<br>* Exercise: Step 1: Participants will walk on a treadmill with standardized walking speed (5.0 km/hour) and slope (15%) for 5 minutes. Step 2: Immediate, one minute, and five minutes post-exercise CPM#1 measurements will be performed at one leg. Exercise and post-exercise CPM#1 measurements will be repeated for the other leg.<br>Other: Questionnaire<br>* Questionnaires NIAPS questionnaire: Baseline NIAPS questionnaire with one additional question about leg dominance. Experience questionnaire: Scores 1-5, questioning the intensity, how painful, the nuisance, the duration of the study and the non-invasive pressure measurements.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Inter-class correlation | The primary endpoint of inter-observer variability will be the intraclass correlation coefficient (ICC) of agreement between three observers, four sites per subject, and four repetitions per measurement. The ICC will be assessed using a two-way random effects model. Both observers and subjects will be included as random effects. The first measurement for each location will be taken from every observer to calculate the ICC. Apart from that, the ICC will be measured using the average of the four repetitions of ratings, to estimate the effect on the ICC of repetitive measurements. Good reliability classification will be reached if the lower bound of the computed ICC confidence interval does not fall below 0.75. | 1 session of approximately 90 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intra-class correlation | The secondary endpoint of intra-observer variability will be the intraclass correlation coefficient (ICC) of agreement within three observers, four sites per subject, and four repetitions per measurement. The ICC will be assessed using a two-way random effects model. Both subjects and repetitions will be included as random effects. The repeated measures will be analysed for each observer separately and this agreement serves to address differences between observers. Good reliability classification will be reached if the lower bound of the computed ICC confidence interval does not fall below 0.75 | 1 session of approximately 90 minutes | 
| Exercise effect on compressibility | The second secondary endpoint is the comparison between post-exercise (immediate, one minute, and five minutes) compressibility and rest compressibility. This will be analysed using a dependent sample t-test. Compressibility is expressed as a CP-value (defined as percentage reduction of the muscle length under two different types of pressure) | Directly, 1 minute, and 5 minutes post-exercise | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Non-invasive, Reliability, Healthy Volunteers