Patellofemoral joint after Attune posterior stabilised fixed bearing total knee replacement

Abstract

INTRODUCTION: Patellofemoral outcome in total knee arthroplasty is variable. The DePuy Attune total knee replacement (TKR) system claims to have a more anatomical patellofemoral design. This case-control study aimed to evaluate the early patellofemoral joint symptoms after either the newer designed Attune TKR or the DePuy press-fit condylar (PFC) TKR. METHODS AND MATERIALS: A case-control study in the form of telephone questionnaire was conducted by a single orthopaedic surgeon to 26 patients with 30 DePuy PFC TKR and 30 patients with 31 DePuy Attune posterior stabilised fixed bearing TKR. All patients did not undergo patella resurfacing but received patella preparation. All operations were performed by 1 of 4 orthopaedic surgeons specialising in joint replacement. Only patients with primary osteoarthritis for primary surgery were included. Mean age was 69 years in the PFC group and 66 years in the Attune group. Their mean follow-up time was 9 months. RESULTS: Statistically significantly lower incidence of constant patellofemoral joint crepitations was found in Attune TKR when compared with PFC TKR (10 vs. 3, p=0.004). No significant differences were found between the incidence of anterior knee pain, pain on stair walking and squatting, Knee Society Knee Scores or Knee Society Functional Scores. There were 4 cases of reported patella clunk for PFC group and 1 in the Attune group but was not statistically significant (p=0.15). DISCUSSION AND CONCLUSION: Patellofemoral outcome depends on an interplay of factors including component positioning, Q-angle restoration, patella preparation, and component design.