RESUMEN
The objective of this study is to compare the clinical effectiveness of two surgical techniques in patients with severe unilateral idiopathic carpal tunnel syndrome. A total of 117 patients were randomized in two groups. In the experimental group ( n = 59) reconstruction of the transverse carpal ligament was performed after open retinaculum release (TCL reconstruction group). In the control group ( n = 58) only retinaculum release was performed (TCL release group). The primary outcome measure was grip strength; secondary outcome measures were pain and response to the Boston questionnaire. Significance was analysed using the t-test or Mann-Whitney test. At 6 months, the experimental group showed clinical and statistically significant improvement in grip strength and decrease in symptom severity. Retinaculum release with reconstruction of the transverse carpal ligament results in improvement of grip strength in the medium term when compared with open retinaculotomy in patients with severe unilateral idiopathic carpal tunnel syndrome. LEVEL OF EVIDENCE: II.