Dissociation of mobile-bearing patellar component in low contact stress patellofemoral arthroplasty, its mechanism and management: two case reports
نویسندگان
چکیده
INTRODUCTION Isolated patellofemoral osteoarthritis can be treated with patellofemoral arthroplasty. CASE PRESENTATION We present two cases of isolated patellofemoral osteoarthritis treated with Low Contact Stress patellofemoral arthroplasty; in both cases the polyethylene mobile-bearing of the patellar component dissociated from the metal backing. One patient had a revision to a Richards patellofemoral prosthesis, and in the second patient the arthroplasty was converted to a total knee prosthesis because of clinically important femorotibial osteoarthritis. CONCLUSION The possible failure mechanisms are described. We suggest avoiding the use of a metal-backed mobile-bearing patellar component due to the risk of dissociation.
منابع مشابه
Patellar polyethylene spinout after low-contact stress, high-congruity, mobile-bearing patellofemoral arthroplasty.
A low-contact stress, high-congruity, mobile-bearing patellofemoral joint arthroplasty decreases the contact force in the patellofemoral joint, theoretically reducing patellar polyethylene wear and increasing implant longevity. This article describes the case of a 47-year-old obese woman who presented with pain and loss of extension after a low-contact stress, high-congruity, mobile-bearing pat...
متن کاملMobile-bearing, congruent patellofemoral prosthesis: short-term results.
PURPOSE To report the short-term outcome of the low contact stress (LCS) patellofemoral prosthesis in 51 knees. METHODS 12 men and 37 women aged 23 to 79 (mean, 53.4) years underwent 51 consecutive LCS patellofemoral replacements. All patients had symptomatic isolated arthritis in the patellofemoral joint with well-preserved tibiofemoral compartments. All knees were evaluated pre- and post-op...
متن کاملEffects of patellar resurfacing on contact area and contact stress in total knee arthroplasty.
The objective of this study was to examine the effects of patellar resurfacing on patellofemoral joint contact pressure and contact area in total knee arthroplasty. We tested seven fresh-frozen cadaveric knees using a custom knee jig which permits the simulation of physiologic quadriceps loading. Before patellar resurfacing, the mean peak contact pressure of medial and lateral patellofemoral jo...
متن کاملThe low contact stress patellofemoral replacement: high early failure rate.
The low contact stress patellofemoral replacement consists of a trochlear component and a modular patellar component which has a metal-backed mobile polyethylene bearing. We present the early results of the use of this prosthesis for established isolated patellofemoral arthritis in 51 consecutive patellofemoral replacements in 35 patients. The mean follow-up was 25 months (5 to 60). The estimat...
متن کاملMobile Bearing Total Knee Arthroplasty for Valgus Knee Osteoarthritis with Permanent Patellar Dislocation: A Case Report and Review of the Literature
Permanent patellar dislocation with tibiofemoral joint osteoarthritis is a relatively rare condition. To treat this condition, total knee arthroplasty with proximal or distal realignment of the extensor mechanism has been reported. We report a challenging case of an 80-year-old woman diagnosed with permanent patellar dislocation with tibiofemoral joint osteoarthritis treated by a mobile bearing...
متن کامل