Analysis of Radiographic Indices in Carpal Tunnel Syndrome

The aim of this study was to compare wrist radiographic indices in patients with idiopathic carpal tunnel syndrome (CTS) with normal cases. The investigators believe that the investigators can contribute to the development of new treatment strategies by determining the radiographic features that contribute to the development of CTS.

Carpal tunnel syndrome (CTS) is the most common mononeuropathy of the upper extremity. It occurs as a result of compression of the median nerve in the carpal tunnel during its course in the wrist. Clinical symptoms are characterized by numbness and tingling in the first 3 fingers and the radial half of the 4th finger, which are compatible with the distribution of the median nerve. Electrophysiologically, it is classified as mild, moderate and severe. As the disease duration increases, atrophy and weakness may develop in the thenar muscles. The incidence is 4-5% worldwide and is more common in women between the ages of 40-60.

Pathophysiology consists of mechanical compression, increased pressure, ischemia in the median nerve and local metabolic changes.

Among the risk factors, occupations that require repeated flexion and extension of the wrist constitute environmental risk factors. Extension can increase the tunnel pressure by 10 times, while flexion can increase it by more than 8 times. Systemic risk factors for CTS are pregnancy, menopause, obesity, renal failure, hypothyroidism, oral contraceptive use, and congestive heart failure.

Diabetes, alcoholism, vitamin deficiency or toxicity, and exposure to toxins are neuropathic risk factors. Localized risk factors include mass lesions that compress the tunnel, arthritis, and radius distal end fractures.

Despite these risk factors, most cases of CTS are still classified as idiopathic.

CTS often develops in the late period after radius distal end fractures. The mechanism here is multifactorial and includes malunion, chronically inflamed synovium, volar callus, and scar tissue. However, in late CTS cases developing after Colles fractures, it has been determined that carpal alignment is greatly affected by the displacement of the radius.

This finding has drawn the attention of researchers to the radiographic features of the distal radius and carpal bone in the etiopathogenesis of idiopathic CTS.

There are several studies conducted on wrist radiographic features in idiopathic CTS.

In a case-control study evaluating the radiographic parameters of 94 wrists of 62 idiopathic carpal tunnel syndrome patients and 94 asymptomatic wrists of 94 controls, radial inclination, volar inclination, ulnar variance and transverse and anteroposterior diameters were measured on posteroanterior and lateral radiographs of the wrist. The measurements were made by two evaluators and the average of the measurements of the two was taken. At the end of this study, a significant difference was found only in ulnar variance and it was reported that positive ulnar variance may be an index to be considered in CTS.

In another study, wrist radiographs of 75 idiopathic CTS patients who underwent carpal tunnel release surgery were compared with the radiographs of 87 normal control group participants. Radial inclination, volar inclination, ulnar variance, radiolunate angle (RLA) and lunate-radius axis distance were measured. Data were measured using two independent raters and the average of these measurements was taken. RLA and lunate-radius axis distance were found to be significant between the two groups. The researchers concluded that excessive dorsiflexion and volar displacement of the lunate can be considered as CTS risk factors.

In another study conducted on female patients with CTS, radiographs of 55 CTS hands of 40 female patients were compared with healthy control subjects. Capitate length, Carpal height, Palm length, Scaphoid-Pisiform Width Index (SPWI) and Palmar ratio values were found to be lower in the patient group. The researchers reported that the carpal bone configuration affects the proximal part of the carpal tunnel and may affect the compression of the median nerve in female patients.

The purpose of this study; to compare the radiographic features of the wrist of patients with idiopathic CTS with the radiographic features of normal control cases. For this purpose, the investigators examined the radiographic features of the distal radius and the scaphoid and lunate bones, which are the two bones that articulate with it and also participate in the posterior proximal floor of the carpal tunnel. The investigators also evaluated whether radiographic features are related to the severity of CTS and symptom severity. The investigators believe that the results to be obtained will contribute to treatment strategies. This study is the first to investigate the relationship between the radioscaphoid angle (RSA), scapholunate angle (SLA) and radiographic indices and symptoms in idiopathic carpal tunnel syndrome (CTS).

Eligibility Criteria:
Inclusion Criteria:

* Not having had any previous surgical procedures on the hand or wrist
* Not having had a major hand or wrist trauma
* No structural disorders in the bone structure

Exclusion Criteria:

* Being under 18 years of age
* History of major hand-wrist trauma or surgery
* Acromegaly
* Rheumatoid arthritis
* Systemic lupus erythematosus
* GUT arthritis
* Psoriatic arthritis