O1206 AUTOLOGOUS PATELLA RECONSTRUCTION DURING TKA IN PATELLECTOMIZED PATIENTS. ISOKINETIC STRENGTH AFTER 6 TO 12 YEARS

Abstract

Aims Patellectomized knees perform poorly with respect to extensor mechanism function and anterior knee pain. Methods: In the period of 1990 to 1995, nine previously patellectomized patients with a mean age of 55 years (range: 38 to 67) underwent cementless Low-Contact-Stress TKA with autologous reconstruction of a new patella. One patient deceased 5 years post surgery. Mean follow-up was 8.0 years (range: 6 to 12) The autograft was taken in five cases from the iliac crest, in two cases from the posterior femoral condyle and in another two cases from the opposite patella at time of simultaneous bilateral TKA surgery. Evaluation included clinical investigation, specific patella score, radiographic analysis and isokinetic strength measurement at 60 degrees per second (Biodex). Results: Clinical scores had a mean of 27 out of 30 points (range: 19 to 30) and mean isokinetic strength of knee extension reached 71Nm (81%) compared with the opposite site. One patient with bilateral patellectomy and unilateral TKA showed an increase of 50% strength (51Nm versus 77Nm) in the kne with TKA and neo-patella. Radiographs in three planes showed minor signs of neo-patella bone resorption in three cases, but evidence of retrabeculation and bone remodelling in all neo-patellae. Conclusions: Reconstruction of a neo-patella in TKA using autograft provides near to normal isokinetic strength, no evidence of considerable autograft resorption, excellent or good clinical outcome and high patients satisfaction after a mean of 8 years. The study provides encouraging data for reconstructing a new patella in patellectomized knees during TKA.