Fixation of Dorsal Lunate Facet Fragments in Distal Radius Fractures Through a Standard Flexor Carpi Radialis Approach

Methods: We retrospectively evaluated all patients with an operated distal radius fracture that had a displaced dorsal ulnar corner fragment from 2007 to 2015 at a single institution. We included 60 patients with a median follow-up of 44 weeks. We used the conventional volar longitudinal approach between the flexor carpi radialis (FCR) tendon and radial neurovascular bundle. All patients were treated with a variable angle plate (VAP) and reduction of the dorsal ulnar lunate facet fragment was achieved using a specialized bone reduction forceps.. Fracture reduction was evaluated using pre- and direct postoperative computer tomography scans of the wrist measuring the articular gap and step.. Bivariate analysis was performed to compare pre- and postoperative radiographic measurements and to compare wrist range of motion.

Results: At follow-up, the flexion, extension, pronation and supination were 92.1%, 96.4%, 99.7% and 99.3% of the unaffected side (p<0.01). The median preoperative articular gap was 2mm (IQR 1.1-3.2mm) and the postoperative articular gap was 0mm (IQR 0-0.7mm), (p=0.08). The median preoperative articular step was 0mm (IQR 0-1.6mm) and the median postoperative articular step was 0mm (IQR 0-0), (p=0.97). There was no postoperative articular gap or step in 66.7% of the patients, in 13.3% the articular step or gap was <1mm, in 15.0% the articular gap or step was 1-2mm and in 5.0% of the patients the articular step or gap was >3mm. The average postoperative volar tilt was 3.9±6.9°, where 36.1% had a volar tilt of ³0°. The average postoperative radial height was 12.0±3.2mm.

Summary: This study shows that dorsal ulnar lunate facet fracture fragments in distal radius fractures can be reduced through a standard FCR with help of intraoperative bone reduction forceps.