Medial Abrasion Syndrome: A Neglected Cause of Persistent Pain After Knee Arthroplasty

Abstract

Introduction: Persistent postoperative pain (PPOP) has detracted from some otherwise successful knee arthroplasties. This study investigated medial abrasion syndrome (MAS) as a cause of PPOP after knee arthroplasty. The surgical techniques and outcomes of incorporating this concept into the management of both primary arthroplasty cases and patients suffering from unknown causes of PPOP after arthroplasties were presented. Materials and Methods: In a one-year period, the author performed unicompartmental or total knee arthroplasty (the UKA or TKA group) that also eliminated medial abrasion phenomenon (MAP) on 196 knees of 150 patients at advanced stages of knee osteoarthritis (OA). During the same year, 16 knees of 16 patients with unknown causes of PPOP after knee arthroplasties were referred to the author for the arthroscopic medial release procedure (the AMR group) after being diagnosed as MAS. Subjective satisfaction, Knee Society Score (KSS), and Knee injury and Osteoarthritis Outcome Score (KOOS) evaluations were used for outcome study.Results: All 166 patients were followed for more than 3 years (mean: 3.7 years, 3.1-4.2) for outcome study. All knees receiving arthroplasty showed medial plicae with MAP at the time of surgery. Only 2 of them suffered from PPOP: one was a neglected tibial plateau fracture with residual varus deformity after UKA and the other was a late infection after TKA and received revision. The satisfactory rate was 98.8% in the UKA group, 99.1% in the TKA group, and 100% in the AMR group. The Knee Society scores and all subscales of KOOS were statistically improved in all groups.Conclusions: MAS is a cause of pain in patients who have received knee arthroplasties, and MAP should be eliminated to ensure a successful knee arthroplasty. PPOP after knee arthroplasty can be caused by MAS, which can be managed by AMR.

Arthroscopic Cartilage Regeneration Facilitating Procedure: A Decompressing Arthroplasty for Knee Osteoarthritis

“…Although the prevalence of medial plica ranges widely, from 18-95% [22]- [24], it is generally agreed that this structure can produce knee pain and can be successfully treated by arthroscopic resection in the event that it becomes in amed, thickened, and/or less elastic [22], [25], [26]. Abrasion phenomenon between the medial plica and the opposite medial femoral condyle has been described in patients with knee OA [6], [27], [28]. The repeated injuries elicited by this abrasion phenomenon was found to trigger IL-1ß production, thus enhance the expression of MMP-3.…”