Comparing the effectiveness of two treatments for severe cubital tunnel syndrome

INTERVENTION: Patients will be blinded and randomly allocated to the study group and control group. Patients in the study group will undergo the conventional ulnar nerve decompression and transposition adding supercharged end‐to‐side pronator quadratus motor branch to motor branch of ulnar nerve transfer. Patients in the control group will undergo conventional ulnar nerve decompression and transposition alone. Final assessments include pinch strength, 2‐point discrimination of the little finger, and Disabilities of the Arm, Shoulder, and Hand Questionnaire. Patients remained in hospital for 2 weeks and were followed up for 24 months. CONDITION: Advanced cubital tunnel syndrome ; Nervous System Diseases ; Advanced cubital tunnel syndrome PRIMARY OUTCOME: Grip strength using a Jamar dynamometer (Sammons Preston Rolyan, Bolingbrook, Illinois), key pinch strength using a pinch gauge (B&L Engineering, Santa Ana, California), and tripod pinch strength (Baseline Hydraulic Pinch Meter, Fabrication Enterprises Inc., Irvington, NY, USA) at baseline and two years SECONDARY OUTCOME: ; 1. 2‐point discrimination of the little finger measured using Disk‐Criminator (MackinnonDellon Partnership, Baltimore, MD) at baseline and two years; 2. Disabilities of the Arm, Shoulder, and Hand measured using Gabel/Amadio score and disabilities of the arm, shoulder, and hand (DASH) questionnaire at baseline and two years; INCLUSION CRITERIA: 1. Age >18 years 2. Severe cubital tunnel syndrome (Akahori’s Classification grade III, IV, and V) 3. A history of cubital tunnel syndrome >6 months 4. Unilateral limb involvement 5. Atrophy of intrinsic hand muscles innervated by the ulnar nerve, which was defined as a sign of advanced disease, no matter manifestation of grip weakness 6. A conduction velocity of 40 m/s or greater 7. No improvement or worse symptoms in mild disease after 3 months of nonsurgical treatments