[Fractures of the wrist with cartilage rupture in young adults. Apropos of 18 cases].

Distal radius impaction fractures are not rare. They present a dual problem for the surgeon: the difficulty of establishing the exact pathological anatomy of the fracture, and of obtaining stable anatomic reduction. The authors report their experience of 18 distal radius impaction fractures in young patients after violent trauma (motor vehicle accident). We subdivided these fractures using Kapandji and Müller's classifications: 12 type 9 or C3, 4 type 5 or B1 and 2 type 4 or C1. The mean depth of impaction of the scaphoid fossa or lunate fossa ("die punch fracture"), or centrally was measured at 5 mm on preop X-rays or on CT scan. After radiographs of the wrist in traction under anaesthesia, open reduction was performed in 14 cases (78%). A volar approach with plate fixation was performed in 3 cases. A dorsal approach with internal fixation with k-wires and an external fixator was performed in the other 11 cases. A bone graft was necessary in 10 cases when the bone defect was significant. The four remaining patients were treated with percutaneous k-wires and external fixation. We reviewed these 18 patients after a mean follow-up of 27 months. The mean age at the time of the accident was 37 years. The results were graded on the Green and O'Brien scale. Results were excellent in 1 case, good in 11 cases, fair in 5 cases, and poor in 1 case. We believe that impaction fractures always require open reduction with or without the addition of bone graft depending on the degree of the impaction. This is because of the risk of arthritic degeneration with this kind of fracture, with articular incongruence (more than 2 mm), and with chondral injuries on the radial or the carpal aspect of the wrist joint. Also, when there is a distal radio-ulnar joint injury (D.R.U.J. dislocation or distal head ulna fracture), the joint must always be stabilized to avoid secondary displacement.