Abstract
Purpose of the study: In young adults, tibial wedge osteotomy performed for the best indications provides good results for about ten years. As these patients get older, knee arthroplasty may be necessary. The purpose of this work was to report operative difficulties and outcome after total knee arthroplasty performed in patients who had had a tibial osteotomy.
Material and methods: We reviewed 20 revision procedures where a posterior stabilised gliding total knee arthroplasty (TKA) was implanted after tibial osteotomy (closed wedge in general). There were 17 patients, mean age 71 years, sex-ratio 0.13; 82% of patients had cardiovascular histories and obesity was noted in 60%. The mean duration of the tibial osteotomy was 7 years. The mean IKS score was 31 and the mean function score 34. The patellofemoral joint presented signs of degeneration in all cases; the patella was low in 12 knees. Mean misalignment was 2 with > 10 varum in one knee and greater than 10 valgum in another. The anteromedial approach was used for 17 knees and the anterolateral approach for the other three. Osteotomy material was removed during the same procedure in five cases.
Results: There was one iatrogenic fracture of the tibial plateau with skin injury. At mean follow-up of 4 years (3–11 years), the mean IKS was 61 points and the mean function score 38. There was one aseptic loosening of the tibial plateau and one lat infection; there were 8 asymptomatic patellar subluxations and 14 low patellae.
Discussion: Tibial osteotomy with a closed lateral wedge for correction of major misalignment poses a difficult problem for subsequent prosthesis implantation. Difficulties include removal of the osteotomy material, the approach, ligament balance, and choice of the implant. Patellar complications can be avoiding by careful alignment of the height of the joint line and proper centring of the extensor system. The discordance between the function and joint score can be explained by the bilateral degenerative disease, by the cardiovascular history, and by the obesity noted in this series.
Conclusion: Tibial wedge osteotomy should be planned with the notion of possible future implantation of a total knee arthroplasty.
Correspondence should be addressed to Ghislaine Patte at sofcot@sofcot.fr
