Abstract
Purpose
The purpose of this study was to examine the progression of osteoarthritis (OA) on patella-femoral joint (PFJ) after open wedge high tibial osteotomy (OWHTO) and unicondylar knee arthroplasty (UKA) in correlation with pain and functional outcomes.
Methods
We conducted a retrospective analysis of 101 knees (89 patients), which received an OWHTO in 42 knees and UKA in 59 knees between 2003 and 2008 with minimum 5-years follow-up. Preoperative and the last follow-up radiologic evaluations were performed on the specific radiographic parameters that reflect the patella and knee alignment. Progressions of OA on PFJ at pre-operation and the last follow up were assessed and compared with modified OA grading system. The patella-femoral (PF) pain and function score were recorded using modified PF scoring system at the last follow up.
Results
Among the radiologic parameters, mechanical axis (MA) and lateral patella tilt (LPT) showed statistically significant differences between OWHTO and UKA. Most of cases showed no progression or just only 1 grade step-up progression on PFJ in both groups and the amount of progression showed no statistical significant between OWHTO and UKA. In comparison of the preoperative and the final follow-up OA grades, medial PFJ in UKA group showed statistically significant differences. The PF pain and function score were comparable in both groups at the final follow up which showed no statistical differences regardless of OA progression.
Conclusions
Overall, 40 ∼ 70% of cases did not occurred the progression of OA in PFJ after OWHTO and UKA. Additionally, at last follow up, the most cases showed the grade 0 or 1 OA in PFJ of both groups. Compared with HTO group, in UKA group, there were tendency of more progression of PFJ compared with preoperative OA status. Finally the degree of OA progressions did not affect the PF pain and functional outcomes.
