We evaluated the postoperative mechanical axis deviation and clinical outcome according to bearing size, femoral component position, and tibial resection angle after unicompartmental knee arthroplasty (UKA). A total of 104 patients with 124 knees underwent Oxford phase 3 UKA. The overall changes in mechanical axis deviation and tibiofemoral angle were significantly different according to bearing size (P = .001 and < .001), but they were not significantly different according to the tibial resection angle and femoral component position. The postoperative mechanical axis fell into the zone C or zone 2 in 108 knees (87%) and into the zone 3 or zone 4 in 16 cases (13%). One hundred eight cases, which had the mechanical axis passing the zone C or zone 2, did not show any progression of arthritis. Limb alignment is a function of the thickness of the bearing rather than alignments of femoral and tibial implant.
- Bearing size
- Implant position
- Mechanical axis
ASJC Scopus subject areas
- Orthopedics and Sports Medicine