Morphometric indices and carpal tunnel syndrome: a radiological study in female patients

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy syndrome of the upper extremities. The carpal tunnel is an osteofibrous canal that is medially bordered by hamulus ossis hamati and pisiform bone, and laterally by scaphoid and trapezoid bones. In this retrospective case-control study, we investigated the relationship between radiologically measured morphometric indices and CTS in female patients.

Clinical, radiological, and demographic data were collected for 55 hands of 40 female patients diagnosed with CTS and 58 hands of control subjects. Radiological measurements included various morphometric parameters derived from wrist and hand X-rays. Statistical analysis was conducted to assess associations between morphometric indices and CTS.

Significant associations were observed between CTS and several morphometric indices, including carpal height, capitate length, palm length, and others. Notably, these values were lower in CTS patients, suggesting a potential link between reduced carpal tunnel volume and increased pressure due to synovial hypertrophy. Additionally, a newly introduced index, Scaphoid Pisiform Width Index (SPWI), showed promise in assessing the proximal part of the carpal tunnel.

It was found that the values for Capitate length, Carpal height, Palm length, SPWI, and Palmar ratio were lower in the patient group. These results suggested that decreasing volume of the carpal tunnel allows for an easier increase in carpal tunnel pressure due to increased synovial hypertrophy and the carpal bone configuration affects the proximal part of the carpal tunnel, and influences the compression of the median nerve, in female patients.