Outcomes of Endoscopic Carpal Tunnel Release With Ring Finger Flexor Digitorum Superficialis Opponensplasty in Severe Carpal Tunnel Syndrome

Purpose To evaluate the outcomes of endoscopic CTR with ring finger flexor digitorum superficialis (FDS) opponensplasty for the treatment of patients with severe carpal tunnel syndrome (CTS). Methods We prospectively studied 52 patients who were graded as having severe CTS by physical examination and electrodiagnostic studies and who underwent endoscopic CTRering finger FDS opponensplasty. Preoperative and postoperative data were collected for active perpendicular thumb abduction; Kapandji score for thumb opposition; grip, key, and tip pinch strength; Medical Research Council score on sensory and motor recovery; SemmeseWeinstein monofilament testing; thenar muscle bulk recovery; and work status. Results Follow-up was 17.5 months on average (range, 7-34 months). Thumb abduction improved significantly from 13.2 degrees (+/- 4.6 degrees) before surgery to 61.7 degrees (+/- 6.4 degrees) afterward. Mean thumb opposition (as measured by Kapandji score) improved significantly from grade 1.5 to 8.7. Tip pinch strength significantly improved from 38.9% to 72.9% of the contralateral side. Medical Research Council scores improved to S3+ and S4 in 85% of patients and to M4 and M5 in 96% of patients. Sensory threshold recovery to 3.61 and 4.31 monofilament occurred in 85% of patients. We observed thenar muscle bulk recovery in 51.9% of patients. Time to return to work was 5 weeks after surgery, on average. Two patients reported scar pain, 2 reported pillar pain, and we found ring finger proximal interphalangeal joint contracture in 3. Conclusions Endoscopic CTR with FDS opponensplasty provides satisfactory outcomes of improved thumb abduction and opposition, sensory and motor recovery, and early return to work in patients with severe CTS. Copyright (C) 2019 by the American Society for Surgery of the Hand. All rights reserved.