762 - Bilateral high tibial valgus osteotomy for medial compartment osteoarthritis.

Objectives: Gonarthrosis is frequently bilateral and a quarter of patients have similar pain in both knees. When a bilateral high tibial valgus osteotomy is indicated, the two procedures are often staggered.

Design: In a series of 69 patients operated on by high tibial valgus osteotomy as part of the conservative treatment of medial compartment osteoarthritis, six patients had bilateral high tibial valgus osteotomy: four by closing wedge stabilized by swan-neck plate blade and two by opening wedge stabilized by internal plate with an integrated metal wedge.

Results: The mean age was 54 years. The average time between the two procedures was 2 years for the closing wedge high tibial osteotomy and 1 year for the opening wedge high tibial osteotomy. Functionally, there was a clear improvement in the IKS functional score from 88 to 140 points, reflecting the patients' good satisfaction with this surgery. Radiologically, the mean mechanical femorotibial angle HKA increased from 168° to 180°, i.e. an average correction of 12°.

Conclusions: The period of off-loading proposed for high tibial osteotomies postoperatively is an obstacle to bilateral osteotomy when compared to the resumption of weight-bearing in prostheses. When the osteoarthritis is bilateral, the obligation sometimes to postpone the second osteotomy by 6 months to a year constitutes a second obstacle to this operation. The possibility of performing a bilateral high tibial valgus osteotomy in one stage with immediate return to weight-bearing seems promising. It remains to be seen which patients are suitable for this double procedure.