TRAUMATIC VOLAR CARPAL INSTABILITY NON-DISSOCIATIVE: A CASE SERIES

Post-traumatic carpal instability non-dissociative (CINDT) occurs from injury to extrinsic and intrinsic wrist ligaments that result in disruption of the relationship between carpal rows. CINDT has been previously reported in association with distal radius fractures, radiocarpal fracture-dislocations, scaphoid fractures, and capsular and/or ligamentous wrist injuries. Previous series report treatment of acute CINDT with ligament repair and delayed CINDT with ligament reconstruction or wrist fusion, with poor outcomes with delayed diagnosis. We present two cases of CINDT-volar intercalated segmental instability (VISI) following Galeazzi injuries with a novel approach in their management. We identified two adolescent patients with CINDT-VISI after Galeazzi fracture with the entire proximal carpal row rotated into flexion with radiolunate angles of greater than 15°. We performed a retrospective chart review for baseline demographics, injury characteristics, treatment course, and clinical outcomes. Radiolunate angles measurements were performed on all sagittal radiographs. Two 14-year-old males sustained closed, isolated, neurovascularly intact Galeazzi injury pattern from falling off a pedal bicycle. Both underwent open reduction and internal fixation of the radius with volar locked plating, pinning of the displaced physeal ulnar head/neck fracture, and pinning of the distal radioulnar joint, and were noted to have CINDT-VISI within two weeks postoperatively. The first patient progressed to a fixed CINDT-VISI deformity with a radiolunate angle of 63.8° by six months. Despite a course of physiotherapy, he had significant limitations in range of motion (25° wrist extension and 65° flexion). Magnetic resonance arthrography showed extensive intraarticular adhesions and volar capsular contracture with dorsal radiocarpal ligament disruption but no intrinsic wrist ligament injury. Seven months postoperatively, he underwent arthroscopic debridement of intraarticular adhesions, removal of the volar locking plate with volar capsular release, and manipulation under anesthesia restored carpal alignment to within normal range, which was maintained with pinning of the radiocarpal and midcarpal joints for eight weeks. At 20 months follow-up, his radiolunate angle was 18.3° with improved range of motion (70° extension and 70° flexion) and no functional limitations other than doing push-ups. The second patient progressed to a radiolunate angle of 40.4° at five weeks postoperatively. He was successfully treated with early aggressive physiotherapy with a radiolunate angle of 19.1° and excellent range of motion (90° extension and 95° flexion) with no functional limitations at one-year follow-up. This is the first report of CINDT-VISI associated with Galeazzi fractures. In previous cases series, patients with fixed CINDT have undergone salvage operation with partial wrist fusion. In our first case, we elected for a soft tissue procedure rather than a salvage arthrodesis given our patient's young age. Based on these two cases and our experience with other CINDT injuries associated with distal radius fractures, our management algorithm includes early aggressive therapy, as early as possible depending on the injury, to allow functional range of motion. If operative intervention is required, careful soft tissue releases with or without ligament repair/reconstruction should be considered even in delayed cases or those with fixed deformity, particularly in younger patients.