Kamil Balaban
Tourniquet-related nerve injury is an uncommon but clinically important complication of extremity surgery. Postoperative radial nerve palsy after humeral shaft fixation is usually attributed to fracture-related injury or surgical manipulation, particularly when a posterior approach is used. We present a case of transient radial-dominant neuropathy following the use of a sterile exsanguination tourniquet during the posterior plating of a distal humeral shaft fracture. A 27-year-old male construction worker with an AO/OTA (Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association) 12A1 spiral fracture of the distal humeral shaft underwent open reduction and internal fixation through a posterior triceps-splitting approach. A sterile exsanguination tourniquet was applied distal to the axilla and proximal to the incision and fracture line for 70 minutes. The radial nerve was identified, looped, and protected intraoperatively. The patient had a normal preoperative neurological examination but developed early postoperative wrist drop, dorsal hand numbness, and palmar-digital paresthesia. Four-week nerve conduction studies demonstrated severe proximal radial neuropathy with milder proximal median nerve involvement and relative preservation of ulnar motor conduction. At four months, repeat studies showed marked electrophysiological recovery, and the patient achieved complete clinical recovery by one year. The radial-dominant but median-associated proximal conduction pattern, together with the location of tourniquet application and recovery profile, was compatible with a compressive neurapraxic mechanism rather than isolated surgical radial nerve trauma alone. Sterile exsanguination tourniquet-related neuropathy should be considered in the differential diagnosis of postoperative radial nerve palsy after humeral shaft fixation, especially when neurological findings extend beyond an isolated radial nerve distribution.