Abstract
Because of post traumatic mal union or constitutionnal intraosseous femoral or tibial deviation, an extra articular deformity may be present in patients requiring TKR. In those cases, recreation of the mechanical axis will affect the orientation of femoral or tibial bone cuts and soft tissue balance. In those important deformities, an extra articular correction may be necessary. Between 1998 and 2013 we performed 31 TKR associated with femoral (6 cases) or tibial (25 cases) osteotomy in one time surgery. This study was prospective and the patients were examinated at 1, 2, 5, 10 and 15 years for the first patients. There were 17 males (one bilateral case) and 13 females with a 63 years average age (from 29 to 79). The deformity was constitutionnal in 14 cases, post trauma in 9 cases, post osteotomy in 8 cases. The extra articular deformity was between 10° and 35°: 15 in varus, 11 in valgus, 2 multidirectionnal, 1 intraosseous flessum, 1 important translation and 1 rotational deformity. In all the cases we used a long stem implant in the osteotomized bone: an osteosynthesis was performed in 26 cases (7 plates, 19 stapples). A posterostabilised prosthesis was used in 28 patients, a CCK implant in 3. We studied pre and post operatively with a 3 to 17 years follow up, IKS scoring, knee motion, knee stability and radiologicaly, HKA, tibial and femoral mechanical angle. In the knees with a varus deformity the average HKA was 158° before surgery and 181 after osteotomy combinated with TKR. In the valgus cases, the average HKA was 198° pre and 179° post operatively. Complications consisted in 1 peroperative fracture, 1 extension lag of 15° and 1 hematoma.
TKR associated with osteotomy seems to be a possible alternative in patients with severe constitutional or post traumatic extra articular deformities after discussion of the other solutions: osteotomy and TKR in two times surgery (particulaly in young patients) or constraint TKR (rotating hinged implants) in patients over 80 years of age.
