Isoelastic resurfacing prosthesis for distal radius fractures: Outcomes in 24 cases with at least 2 years' follow-up

Background: Unicompartmental resurfacing prostheses have been reported to be useful for treating comminuted fractures involving the distal radial joint surface in elderly patients with osteoporosis. However, the data on this method remain scarce and further evaluations are needed. The objective of this study was to evaluate the clinical and radiological outcomes after unicompartmental resurfacing prosthesis implantation in patients with distal radius fractures and at least 2 years' follow-up.

Hypothesis: Outcomes with Prosthelast® are as good in the mid-term as in the short term.

Materials and methods: We studied 24 patients with type C fractures in the AO classification. The Prosthelast® prosthesis was implanted in each. Mean age was 78 years (60 to 91). There were 22 females. Three of the fractures were open. The patients were evaluated clinically using a visual analogue scale (VAS) for pain, ranges of motion at the wrist, and grip strength. In addition, functional scores were determined, and radiographs obtained.

Results: Mean follow-up was 55.2 months (24-97). Mean tourniquet time was 61.9minutes (37-126). Mean motion ranges were 39° in flexion, 49° in extension, 74° in pronation, and 68° in supination. The mean VAS pain score was 2.1 (0-7). The mean Quick DASH was 39.8 (9.09-77), the mean PRWE was 42.7 (5-95), and mean grip strength was 38 (25-150). Painful motion limitation of the elbow was noted in a patient treated with total elbow prosthesis. Complex regional pain syndrome developed in 6 patients, and 5 patients required revision surgery. Asymptomatic perforation of the radial head occurred in 8 patients. No cases of peri-prosthetic osteolysis or osteoarthritis were noted. The prosthesis impinged on the lunate bone in 2 patients and on the scaphoid bone in one patient. Mean ulnar variance was +0.17mm (-1 to 7.5). Bone remodelling about the prosthesis was noted in all the patients, but 2.

Discussion: Our data obtained after a mean follow-up of 55 months indicate that resurfacing prostheses have a role to play in the treatment of comminuted articular fractures in patients with osteoporosis. A long-term study is needed to further evaluate these results.

Level of evidence: IV; therapeutic.