Abstract
Introduction Full flexion is important for daily living activities in Asian societies. The purpose of this presentation is to discuss our experience with full flexion after knee replacement in over 900 cases and to address some areas of concern.
Materials and Methods 911 cases were performed on 492 patients. LPS flex implants were used; all surgeries were performed by a single surgeon between December 1999 and august year 2004. Data was processed at University of Dundee in Scotland. MIS subvastus approach was used. Full flexion was defined as a flexion of over 135 degree with the ability to kneel on the ground, calf touching thigh for at least one minute. X-ray review was carried on cases with more than 2 years of follow up.
Results 67% of patients were able to get full flexion after surgery. The majority of those cases had full flexion pre-operatively. The results were compared with the data base at University of Dundee: our patients has significantly better flexion than the data base yet the knee score was almost the same .Complication rates were the same and there was no complication that can be attributed to deep flexion.
Discussion The result clearly shows that in spite of the fact that patient has a better range of motion the knee score failed to capture the improvement of patient function. It is unfortunate that we still do not have a universal way to describe the activities of deep flexion and no objective methods to assess the importance of deep flexion on daily activities. There is still great need to improve our understanding of the biomechanics of deep flexion so we can choose proper implants for our patients. Our x-ray review shows that mobile bearing is better choice in accommodating the lateral femoral condyle subluxation that happens with deep flexion and we were able to document that on 3D images.
Conclusion Full flexion is achievable and safe after TKA. Further work will be needed to develop new ways to asses function after TKA and to further modify the implant to accommodate deep flexion.
Theses abstracts were prepared by Professor Roger Lemaire. Correspondence should be addressed to EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
