title: The Avon Patellofemoral Joint Replacement: Mid-Term Prospective Results from an Independent Centre.
abstract: BACKGROUND
  Approximately 10% of patients with osteoarthritis (OA) of the knee have unicompartmental OA confined to the patellofemoral joint (PFJ). The main surgical options are total knee replacement (TKR) and PFJ replacement (PFJR). PFJR has a number of advantages over TKR, including being less invasive, preserving the unaffected parts of the knee, allowing faster recovery and better range of motion and function. We report our prospective mid-term results of the Avon PFJR for established isolated PFJ arthritis in 61 consecutive procedures.
  
  
  METHODS
  Sixty-one Avon PFJRs were performed in 57 patients. The outcome measures were the new Oxford knee score (OKS), Hungerford and Kenna score (HKS), and Crosby Insall knee scores. Only patients with severe isolated PFJ OA were included. The diagnosis was based on a combination of clinical, radiological and, where available, arthroscopic findings.
  
  
  RESULTS
  Mean follow-up was 5.09 years (range, 12 to 124 years). There were 2 revisions in the first 5 years. The median HKS score was 80 (interquartile range, 70 to 95) and the mean OKS was 31.8 (± standard deviation, 8.7) at 5 years. These were significantly better (p < 0.001) than the preoperative scores.
  
  
  CONCLUSIONS
  The Avon prosthesis gives good functional outcomes in the medium term and survives well. Our data support other studies in the literature and is the largest independent prospective study to date.
authors.affiliation: Orthopaedic Department, East Sussex Healthcare NHS Trust, The Conquest Hospital, Hastings, UK.
authors.forename: Pouya
authors.initials: P
authors.lastname: Akhbari
authors.affiliation: Orthopaedic Department, East Sussex Healthcare NHS Trust, The Conquest Hospital, Hastings, UK.
authors.forename: Tamer
authors.initials: T
authors.lastname: Malak
authors.affiliation: Orthopaedic Department, East Sussex Healthcare NHS Trust, The Conquest Hospital, Hastings, UK.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Dawson-Bowling
authors.affiliation: Orthopaedic Department, East Sussex Healthcare NHS Trust, The Conquest Hospital, Hastings, UK.
authors.forename: Debra
authors.initials: D
authors.lastname: East
authors.affiliation: Orthopaedic Department, East Sussex Healthcare NHS Trust, The Conquest Hospital, Hastings, UK.
authors.forename: Kim
authors.initials: K
authors.lastname: Miles
authors.affiliation: Orthopaedic Department, East Sussex Healthcare NHS Trust, The Conquest Hospital, Hastings, UK.
authors.forename: P Adrian
authors.initials: PA
authors.lastname: Butler-Manuel
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee; D005260:Female; D006801:Humans; D008297:Male; D057071:Patellofemoral Joint / Q000601:surgery*; D011446:Prospective Studies; D013997:Time Factors; D016896:Treatment Outcome
keywords: Arthroplasty; Patellofemoral joint; Survival rate; Survivorship