Hand and Upper Extremity Unit, Hospital Fremap, Majadahonda, Madrid, Spain

Purpose: To compare the functional results and workers´ compensation of radial head replacement with metallic and pyrocarbon implants.

Material and Methods:A randomized prospective study. 37 patients with conminuted radial head fractures. 36 months (range, 12-82 months) of mean follow-up. The mean age were 38 years (range, 24-54 years) and all patients were medium or high level workers. Six fractures were Mason type III and 31 Mason-Johnston type IV. 17 patients (group 1) were treated with r-Head® metallic modular prosthesis (Avanta, San Diego, USA) and 20 (group 2) with the MoPyC® pyrocarbon modular prosthesis (Bioprofile, Grenoble, France). Postoperative complications, pain (visual analogue scale), clinical and functional outcome based on MEPS and DASH score, X-ray evaluation, time to return to work and activity level were evaluated and compared at the end of follow-up.

Results: Similar results were obtained in the two groups. 3 patients required implant removal (group 2). Results at the end of FU : VAS 3.5 (g1), 3.8 (g2) ; mean arc of FE : 87.5 º (g1), 91º (g2) ; mean rotation arc : 132º (g1) and 125º (g2); DASH : 32 (g1) and 45 (g2) ; MEPS : 88 (g1) and 78 (g2). We found radiolucent lines in X-ray in 90%, but were asintomatics. Located around the stem (zones 1 to 7) in the g1 and only in the proximal area (zones 1 and 7) in the g2. The average time to return to work was 7.2 months (3-16 months) with no significant statistical differences among the 2 type of implants regarding work related results.

Conclusion: Radial head replacement presented good results for the treatment of comminuted radial head fractures. We did not find big diferences between the metallic and pyrocarbon implants. Pyrocarbon implants showed lesser radiological signs of loss of fixation than metallic prosthesis.