Dorsal percutaneous cannulated mini-screw fixation for fractures of the hamate hook

Open fixation of acute fractures, delayed union and non-union of the hamate hook through a palmar approach has been reported. Minimal invasive fixation using a dorsal percutaneous approach and a headless cannulated mini-screw is another option not commonly considered. The authors present their case series of patients who underwent dorsal percutaneous fixation of acute fractures and delayed union of the hamate hook.

This study retrospectively reviewed six consecutive patients (five male patients and one female patient) with non-displaced acute fractures (< 8 weeks) and delayed union (8 to 12 weeks) of the hamate hook treated with dorsal percutaneous cannulated mini-screw fixation. The indications for surgery included wrist pain, patient refusal of conservative treatment, and prevention of non-union and hook excision. Exclusion criteria included displacement or inadequate size of the hamate hook, previous surgery, associated carpal injury, flexor tendon rupture, and median or ulnar nerve lesion in the carpal tunnel and Guyon's canal respectively. Each fracture was visualized by radiography and computed tomography before and after the intervention.

Anatomically correct fixation of the hamate hook with central screw positioning was achieved in all patients. No displacement or disruption of the cortical shell of the hook was observed. The union rate was 100% with all patients being able to resume their pre-injury activities after an average of seven weeks from surgery.

This pilot study demonstrates that non-displaced acute fractures and delayed union of the hamate hook can be treated successfully by dorsal percutaneous cannulated mini-screw fixation with minimal morbidity and complications.