Revision arthroplasty with rotating hinge systems for total knee arthroplasty instability.

Abstract

Restoring stability after total knee arthroplasty (TKA) and improving joint function using acemented rotating hinge system. Ligament instability and/or osseous defects (including Anderson Orthopaedic Research Institute [AORI] classification typeII defects) after primary TKA or TKA revision surgery. Distal femoral or proximal tibial bowing requiring implant systems that provide femoral or tibial offset stems. Persistent periprosthetic infection. Poor therapeutic compliance. AORI typeIII defects. Medial arthrotomy. Femoral and tibial component removal with small saw blades and chisels. Intramedullary alignment for the tibial and femoral cuts. Debridement and removal of membranes and cement remnants. Reconstruction of joint line and correct TKA alignment. Trial reduction. Cement fixation. Unrestricted range of motion, partial weight bearing for 4weeks. Between 2012 and 2013, 18patients suffering from ligament insufficiency after TKA were revised using the described system and included in aprospective study protocol. The mean follow-up was 37months (range 30-46months). There was asignificant improvement of the Oxford Knee Score (OKS) from 19 (range 7-29) preoperatively to 29 (range 10-45) postoperatively (p = 0.004). The Knee Society Score (KSS) knee assessment subscore improved from 35 (range 9-70) to 67 (range 35-97) (p = 0.002) and the pain score from 7 (range 0-50) to 24 (range 0-50) (p = 0.008).