The Influence of Transverse Carpal Ligament Thickness on Treatment Decisions for Idiopathic Mild to Moderate Carpal Tunnel Syndrome

Abstract

Purpose The main cause of carpal tunnel syndrome (CTS) is pathological changes in the flexor synovium, which is a known cause of pressure elevation in the carpal tunnel. The importance of the transverse carpal ligament (TCL) in the pathogenesis of CTS has hitherto been overlooked. However, the TCL significantly affects carpal biomechanics; the TCL is known to affect the carpal bone to a greater extent when intra carpal tunnel pressure is high. In addition, the effect of TCL properties on the progression course of idiopathic CTS is unknown. Therefore, we hypothesized that TCL thickness, measured using ultrasonography, would influence the results of conservative treatment for CTS patients with mild to moderate symptoms. We aimed to investigate the relationship between the ultrasound-measured TCL thickness and idiopathic carpal tunnel conservative treatment surgery rate. Materials and Methods We analyzed the wrists of 127 patients with mild to moderate symptoms of CTS. The patients were diagnosed on the basis of electrophysiological assessment outcomes, median nerve cross-sectional area in the carpal tunnel, and clinical symptoms. The Boston carpal tunnel questionnaire score was also measured. Patients with a TCL thinner than 1.5 mm were classified into group A (n = 62), and those with a TCL thicker than 1.5 mm were classified into group B (n = 65). Patients with severe symptoms or other diseases were excluded. The patients were initially treated with night splinting after diagnosis. If symptoms were not ameliorated, steroid injection and surgical treatment were performed consecutively. The procedures were determined by a single surgeon. Results The mean TCL thickness was 1.51 mm: 0.98 mm in group A and 2.28 mm in group B. The percentages of patients who underwent surgery were 43.0% in group A and 67.7% in group B. Group B was 1.77 times more likely to have surgery, and the interval between diagnosis and surgery and/or steroid injection was shorter. The TCL thickness in group B was also related to cross-sectional area and symptom duration. Conclusions Transverse carpal ligament thickness affects disease progression and may affect treatment efficacy, depending on the treatment method. Transverse carpal ligament thickness may be a criterion for deciding between surgical and conservative treatments based on a thickness threshold of 1.5 mm.

Evaluation of the Transverse Carpal Ligament in Carpal Tunnel Syndrome by Shear Wave Elastography: A Non-Invasive Approach of Diagnosis and Management

“…In this study, the thickness of the TCL at the DCT in positive hands in the patient group ranges from 0.11 to 0.18 cm, and in the control group ranged from 0.1 to 0.12 cm. These values were similar to other US-based in vivo studies, but thinner than some cadaver studies (15,28,29). The possible reason for this disparity is that the edge of thickened TCL is often blurred in US images because of the reconstruction in patients with CTS.…”

“…In addition, we performed more comprehensive comparisons between patients and healthy controls, and between different subgroups and found various correlations between TCL and NCS. Another creative study (29) investigated the TCL thickness and the associations with treatment methods. TCL thickness and stiffness were also included in our study, but the TCL thickness was not significantly related to NCS.…”

Use of conservative therapy before and after surgery for carpal tunnel syndrome

“…Carpal tunnel syndrome (CTS) is a common complaint causing hand disability in people of working age [1][2][3]. CTS is suggested to be caused by compression of the median nerve in the carpal tunnel under the transverse carpal ligament due to thickening of the ligament or other structures surrounding the median nerve [4,5]. In the chronic condition, compression and irritation of the median nerve is followed by tingling, numbness, and pain in the innervation area of the median nerve.…”

Mutations in COMP cause familial carpal tunnel syndrome

“…TS, characterized by paresthesia, pain, and numbness in the hands due to excessive pressure on the median nerve, is a common disorder treated by hand surgeons 1,2 . CTS is often caused by swelling and thickening of soft connective tissues surrounding the median nerve within the carpal tunnel, rather than a problem with the nerve itself [3][4][5][6][7][8][9] . Enlarged and fibrotic soft connective tissues can result in compression or traction on the median nerve at the carpal tunnel.…”