Abstract
Aims: determine functional outcome of revision Avon patellofemoral replacements (PFR), converted from primary Lubinus PFR.
Materials and Methods:
Prospective review of 11 knees (8 patients, 6 female).
Average age at primary PFR – 64 years
Indication – isolated patellofemoral osteoarthritis (11), patellofemoral instability (3)
9 knees (7 patients) temporarily improved.
Revision Avon PFR at average 83 months after primary procedure.
Indication – polyethylene wear
polyethylene synovitis
femoral component malposition
At review:
average 61 months after revision
age – 70 years 10 months.
fixed flexion contracture 1.7°
maximum flexion 111°.
Bristol knee score improved from average of 54.5 to 77.2. Pain score component averaged 25, functional component averaged 16.9. No malalignment or instability.
Average American Knee Society Score 132.8
Bartlett patellar score 19.8
Three patients (4 knees) had medical problems contributing to their functional incapacity.
No radiological complications except minor polyethylene wear on lateral facet of one patella. Progression to tibiofemoral osteoarthritis (Ahlburgh grade 1) in 3 knees.
Discussion: Primary Lubinus PFR temporarily improved 82% of knees. Maltracking/polyethylene wear was usual cause for failure. Revision to Avon PFR resulted in substantial improvement of pain and function.
Conclusion: revision Avon PFR can provide a suitable alternative to revision to total knee replacement.
Honorary Secretary – Mr Roger Smith. Correspondence should be addressed to BASK at the Royal College of Surgeons, 35 - 43 Lincoln’s Inn Fields, London WC2A 3PN
