Abstract
Purpose: There are three main causes of failure after valgisation osteotomy of the tibia requiring repeated osteotomies: insufficient valgus, excessive valgus, or loss of the valisation correction after a variable delay. The purpose of this study was to evaluate outcome after repeated oseotomies performed in relatively young patients or too active to propose arthroplasty. The technical problems were different for each aetiology.
Material and methods: The series included 47 knees operated on between 1974 and 1998 after a first osteotomy performed at a mean age of 46 years. Mean delay between the two operations was five years (1 to 12). A medial closure osteotomy had been performed at the first operation in 34 cases and a lateral opening osteotomy in 13. For the 19 knees with valgus, the second osteotomy was a medial closure in 14 and a lateral opening in five. A repeat valgisation was performed in 28 cases, 18 by lateral closure, one by medial opening and nine by curviplanar osteotomy. The IKS score was determined to assess function. The femoraotibial axes (HKA angle) were determined on full stance views. The Ahl-back osteoarthritis grading was used. For 17 patients who had undergone operations in other institutions, exact measurements were not always available concerning the preoperative status and the initial correction.
Results: The overall IKS score for function improved in 87% of the cases with a mean follow-up of five years. The IKS knee score improved from 73 to 89 points and the IKS function score from 65 to 81 points. For the 19 over-corrections, the mean HKA angle was changed from 190° to 184°. For the 28 under-corrections, the mean HKA angle was changed from 173° to 182°. The tibial tilt remained unchanged at 7° as did lateral gapping at 3°. Delay to consolidation was a mean 96 days.
Discussion: Revision osteotomies performed for correction defects should be distinguished. For these procedures, it would be logical to expect a good result if a 3 to 5 degree valgus is achieved. Revisions after a long period (33 cases) are different; required for wear, these cases correspond to progressive loss of the initial osteotomy effect. These patients are often candidates for prosthesis if seen after 70 years. Good results can however be obtained with a second osteotomy irrespective of the initial technique. We prefer reoperating with medial opening after initial lateral closure.
The abstracts were prepared by Pr. Jean-Pierre Courpied (General Secretary). Correspondence should be addressed to him at SOFCOT, 56 rue Boissonade, 75014 Paris, France
