Complications of Medial Unicompartmental Knee Arthroplasty

Abstract

BackgroundWe report intra- and postoperative complications of unicompartmental knee arthroplasty (UKA).MethodsThis study was conducted on 246 cases of UKA which were performed for degenerative osteoarthritis confined to the medial compartment, from May 2002 to May 2010, for which follow-up periods longer than one year were available. Complications were divided into intra- and postoperative complications. Pre- and postoperative clinical scores, the range of motion, and radiologic findings were analyzed.ResultsComplications developed in a total of 24 cases (9.8%, 24/246). Among them, 6 cases had intraoperative complications while 18 had postoperative complications. Among the 6 intraoperative complications, one fracture of the medial tibial condyle, two fractures of the intercondylar eminence, one rupture of the medial collateral ligament, one widening of the peg hole leading to femoral component malposition and late failure, and one total knee arthroplasty (TKA) conversion of a large bony defect of tibial avascular necrosis were observed. Among the 18 postoperative complications, four cases of aseptic loosening of the femoral component, one soft tissue impingement due to malalignment, nine cases of polyethylene bearing dislocation, one case of suprapatellar bursitis, one periprosthetic fracture, one TKA conversion due to medial component overhanging, and one TKA conversion due to pain of unexplained cause were observed.ConclusionsThe mid-term clinical outcomes of UKA were excellent in our study. However, the incidence of complications was very high (9.8%). To prevent intra- and postoperative complications, proper selection of the patients and accurate surgical techniques are required.

Short-term effectiveness of medial unicompartmental knee arthroplasty in young patients aged less than or equal to 60 years

“…Kim et al 43 analyzed 89 patients with complications of various reasons after UKA showed that two cases caused by unexplained pain. Hun et al 44 followed up 246 patients who received UKA for more than 1 year, and the incidence of postoperative complications was 9.8%, a case was revised to TKA for unexplained pain. Bhattacharya et al 45 explained that the reasons of the unexplained pain after Oxford-UKA may be related with the position of prosthesis or soft tissue stimulation, yet there are still a large number of unexplained causes is difficult to find exact reasons.…”

Superior bearing dislocation in a unicompartmental total knee prosthesis

“…Bearing replacement with an upsized bearing is typically performed for simple bearing dislocations with an otherwise intact prosthesis. In cases with component loosening revision with a replacement OUKP or total knee arthroplasty is typically performed [8], [9].…”

Bone Defects in Revision Total Knee Arthroplasty and Management

“…K nee arthroplasty is a surgical procedure undertaken to replace the weight-bearing surfaces of the knee joint to restore capacity and function 1 . It can be performed as a partial, also called unicompartmental arthroplasty (UKA, which replaces only the damaged surfaces retaining any undamaged parts) or a total knee arthroplasty (TKA) 2,3 . TKA involves replacement of all three compartments of the knee, known as the medial compartment (inside aspect of the knee), the lateral compartment (outside of the knee), and the patellofemoral compartment (the joint between the patella and the femur) 4 .…”