Does Removing Patellofemoral Joint Osteophytes Reduce Anterior Knee Pain Following Unicompartment Knee Arthroplasty?

Background: Anterior knee pain (AKP) is a challenge following unicompartmental knee arthroplasty (UKA). Some surgeons remove patellofemoral joint (PFJ) osteophytes to reduce osteophyte impingement and AKP. However, there is evidence that PFJ osteophytes compensate for knee osteoarthritis (OA) by increasing and improving stability and increase contract surface area in knee osteoarthritis. Moreover, when PFJ osteophytes are not removed, some studies report good clinical outcomes. The issue of removing or leaving PFJ osteophytes is controversial.

The objective of this study was to compare AKP following mobile bearing UKA after removing or leaving PFJ osteophytes.

Methods: The prospective non-randomized study included 89 isolated medial osteoarthritis (OA) of knee. They were classified into 2 groups. Group (Gp)1 was removing PFJ osteophytes; consists of 44 knees. Gp2 was non-removing PFJ osteophytes: consists of 45 knees. The patients were follow up and recorded incidence of AKP and VAS for AKP at 6 weeks, 3months, 6 months, 1 year and 2 years. No patients were lost to follow up. The patellar tilt and shift were measured at 6 weeks, 3months, 6months, 1year and 2 years via skyline view radiography. The knee society scores, Oxford knee score, knee injury and osteoarthritis outcome score, forgotten joint score and Kujala scale also were recorede at 6 weeks, 3months, 6months, 1 year and 2 years.