Abstract
Aim: To assess the results and complications of the opening wedge form of distal femoral varus osteotomy (DFVO) in treating valgus arthritis and ligament instability of the knee.
Methods: Patients undergoing DFVO were assessed prospectively using validated scoring systems and pre/post operative alignment radiographs. All had failed non operative and arthroscopic procedures and were keen to avoid arthroplasty. The lateral based opening wedge osteotomy aimed to correct the weight bearing line to position 50% medial to lateral and was held with either the Puddu femoral plate (Arthrex UK) or the Tomofix plate (Synthes UK).
Results: 26 distal femoral osteotomies were performed in 23 patients with a mean age of 34 (16 –58). The mean duration of follow up is 32.5 months (1–72). 8 were undertaken for primary valgus malalignment, and 15 for secondary valgus with OA due to previous lateral menisectomy. Simultaneous additional procedures included microfracture (3), MACI (1), meniscal transplantation (1), and MCL advancement (1). Mean hospital stay was 4 days (2–6). Post op alignment was out by greater than 10% of intended in 2/3. 3 early major complications required re-operation: 2 for plate and screw cut out and 1 for infection. 2 developed delayed union requiring bone grafting. Failure with conversion to arthroplasty has occurred in 2 (1 lateral UKA, 1 TKA), and 2 patients are awaiting either multi-ligament reconstruction or collagen meniscal implantation. The overall mean Tegner score is 4 (2–6), and 20 of the 23 patients feel satisfied with the outcome having avoided arthroplasty.
Conclusion: Opening wedge DFVO is a technically difficult procedure with significant complications, but in the right indication offers long lasting pain relief and joint preservation prior to arthroplasty. New techniques including accurate closing wedge fixation systems and computer guided operative planning and surgery may offer improvements to this vital surgical option.
Correspondence should be addressed to Mr T Wilton, c/o BOA, BASK at the Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London WC2A 3PE, England.