Fracture of the distal radius - outcome, primary surgery and treatment of malunion

University dissertation from Department of Clinical Sciences, Lund University

Abstract: A consensus protocol for treatment of distal radius fractures (DRF) has been developed to aid clinicians in treatment decision making. The protocol was evaluated in Paper I using a validated subjective outcome instrument, DASH in 518 consecutive patients. A good final subjective result was achieved with the proposed protocol, regardless of initial severity with a low median DASH score in all groups at final follow up 1 year after the fracture. No differences were seen for the various operative techniques.

In Paper II, 50 patients with an unstable or complex DRF were randomized to either closed reduction and external fixation, or open reduction and internal fixation using the TriMed® system. Pronation/supination and grip strength were better in the internal fixation group at one year compared to the external fixation group. There were no differences in DASH scores or in radiographic parameters.

In Paper III we investigated function in patients following an osteotomy due to a malunion after a DRF. Instead of autologous iliac crest bone graft we used a slow resorbing bone substitute (Norian SRS®), consisting of hydroxyapatite, to fill the gap in combination with the TriMed system for fixation. We were able to improve forearm rotation, flexion/extension and radioulnar deviation from. Grip strength increased and DASH scores decreased substantially. The achieved radiographic correction was consistent over the first year but the resorption was slow and the time to remodel was long.

In Paper IV a novel bone substitute (Cerament®) was used with a faster resorbing mixture of calcium phosphate and calcium sulphate. 15 consecutive patients with a radiographic and clinically manifesting malunion after a DRF underwent an osteotomy. The same technique was used for fixation of the osteotomy as in Paper III but this time with Cerament® as bone substitute. Grip strength increased and DASH scores decreased. A fast remodelling of the bone was noticed but also an increase of ulnar variance from immediately postoperatively to final follow up. Using a bone substitute, the operation can be performed as an outpatient procedure and donor site pain avoided. Osteotomy of the distal radius is an effective treatment for malunited distal radius fractures, but perhaps a more rigid fixation is needed in fast remodelling bone substitutes.