Abstract
The purpose was to evaluate clinical and radiographical outcome of 1777 patella non-resurfacing in two major centres. Patella management in total knee arthroplasty (TKA) is of concern when resurfaced (multiple problems) or when non-resurfaced (pain). Reports in the literature are frequently non-specific regarding surgical approach, femoral rotation alignment, and femoral design.
1777 non-resurfaced patella TKAs from two large centres were evaluated with a 2 to 15 year follow-up, using similar selection criterion, operative techniques, and prostheses. Patient demographics included 70% females (mean age 68 years). Diagnoses included 8% rheumatoid. Radiologic skyline view assessment of 200 cases (100 from each centre) with longest (mean 9. 2 years) follow-up, formed a subset group. Clinical success rate was good/excellent in 94. 6%; scores improved from 59 to 87.
Patella-related anterior knee pain requiring re-operation was 1. 1% (19 patients), only 9 (0. 55%) of which had unequivocal improvement following re-surfacing. Twenty-one cases (1. 2%) underwent “incidental” patella resurfacing at revision for other reasons. There were no patella subluxations or dislocations. Two hundred cases with longest follow-up revealed perfect congruent contact in 97. 5% with no lateral deviation (mid-sulcus to patella crown) over 6 mm. Asymptomatic remodelling was noted in 8%, with relative sclerosis and height loss of the lateral facet in 2. 5%. No changes correlated with clinical symptoms.
These data support a success rate of over 98% with non-resurfaced patella in a mobile-bearing (LCS) TKA system that includes a patella friendly design, proper soft tissue management, and femoral component rotational alignment using the tibial shaft axis and balanced flexion tension gap method.
The abstracts were prepared by Mr Simon Donell. Correspondence should be addressed to him at the Department of Orthopaedics, Norfolk & Norwich Hospital, Level 4, Centre Block, Colney Lane, Norwich NR4 7UY, United Kingdom
