Functional Outcomes of Zancolli Lasso Versus Modified Stiles-Bunnell Techniques for Post-Leprosy Ulnar Claw Hand Correction: A Prospective Randomized Comparative Study

Background: Leprosy, caused by Mycobacterium leprae , leads to peripheral neuropathy, commonly affecting the ulnar nerve, resulting in claw hand deformity. Various tendon transfer techniques, such as the Modified Stiles-Bunnell (flexor digitorum superficialis 4-tail [FDS-4T]) transfer and Zancolli lasso procedure (ZLP), are used for surgical correction. However, comparative studies assessing their functional outcomes are scarce. This prospective, randomized comparative study aimed to evaluate improvements in hand function, grip strength, and range of motion (ROM) between the 2 techniques.

Methods: Fifty patients with post-leprosy ulnar claw hand were randomly assigned to undergo either FDS-4T (n = 25) or ZLP (n = 25). Preoperative and postoperative assessments included active metacarpophalangeal (MCP) joint ROM, grip strength, patient-reported outcome measures, and photographic grading of claw correction. Statistical analyses were performed using paired t tests and Pearson correlation, with significance set at P < .05. Results: Both groups showed significant postoperative improvement in MCP joint ROM ( P = .0001) and grip strength ( P = .0001). Grip strength recovery was higher in ZLP (129%) than in FDS-4T (117%; P = .013). Claw correction was rated excellent in 12 patients (FDS-4T) versus 7 patients (ZLP), although not statistically significant. Zancolli lasso procedure had shorter operating time and faster return to daily activities ( P = .02). Conclusion: Both procedures significantly improved hand function without a clear superiority of one over the other. While ZLP offered faster recovery and grip strength, FDS-4T showed slightly better claw correction. The choice of procedure should be tailored to patient needs.