Double-Level Osteotomy in Severe Varus Malalignment to Optimize Knee Joint Restoration

Background: Lower extremity alignment-correcting procedures for unicompartmental osteoarthritis are experiencing a rapid rise. Medial open-wedge high tibial osteotomy (MOW-HTO) thereby represents the most common technique among osteotomies but is limited in cases of severe malalignment. Some cases make a double-level osteotomy necessary. Indications: If planning of malalignment correction using a MOW-HTO results in a mechanical medial proximal tibial angle (mMPTA) of more than 93° (causing an oblique joint line), double-level osteotomy is indicated to avoid nonphysiological knee kinematics. Technique Description: After clinical examination and detailed analysis of malalignment (full-weight-bearing long-leg radiograph: hip-knee-angle [HKA], mMPTA, mechanical lateral distal femoral angle [mLDFA], joint line convergence angle [JLCA]), as well as individualized planning of the correction, the surgical procedure starts with an arthroscopy to evaluate the cartilage conditions and eventually treat intraarticular pathologies. Then, the femoral supracondylar correction is performed (closed wedge, biplanar osteotomy [ to increase bony healing]) according to the presurgical planning by resecting the osteotomy wedge with the measured length. K-wires are placed to check the correction. An angle-stable plate is used for osteosynthesis. The wedge taken out will be used as bone stock for the MOW-HTO afterward. The biplanar open-wedge tibial osteotomy is then performed subsequently using a medial tibial approach and an angle-stable plate. Opening of the osteotomy is then performed and double checked with intraoperative fluoroscopy using an alignment rod. Postoperative partial weight bearing for 6 weeks is recommended. Results: In recent literature, only few publications report on results of double-level osteotomies. Babis et al reports that it is a valuable procedure for patients with large varus deformity. Nakayama et al noted a significant improvement in patient-registered clinical outcomes in early postoperative evaluation of 20 patients. Schröter et al reports on 37 knees and findings include good clinical results, despite progressive osteoarthritis. Discussion/Conclusion: In cases of severe malalignment, adequate axis correction may require a double-level osteotomy. Exact preoperative planning is essential. Results reported in recent publications are promising. By splitting 1 large correction into 2 smaller ones, complications like hinge fracture and delayed bone healing are lowered.

Comparative analysis of the results and complications of two methods of the open wedge high tibial osteotomy

Objective – to compare the results and complications of open wedge high tibial osteotomy (OWHTO) in patients operated on according to the standard technique and using the developed method of performing the operation using the original fixator.Materials and methods. 73 patients with primary and secondary OA of the knee I–III stages were recruited into the study, which were divided into 2 groups. Group 1 consisted of 43 patients, who underwent 46 OWHTO from 2005 to 2019 using the standard technique using short plates with a fixed spacer (Puddu I (5 times) and II generation (24 times), Osteomed (17 times)) and bone grafting. Group 2 consisted of 30 patients who were operated on in 2018– 2020 using the developed surgical technique and the original fixator. To assess the result, we studied the change in pain according to the Visual Analog Scale (VAS), as well as the functional (FS) and objective scores (OS) of the knee according to the Knee Society Score (KSS) before surgery, after 3 months and 1 year after OWHTO.Results. In group 1, one year after OWHTO, the results were obtained: excellent in 43.5% of cases, good – in 41.0% and satisfactory – in 15.2% of patients. In group 2, an excellent result was obtained in 59.3% of patients, good – in 33.4% and satisfactory – in 7.3% of cases. In group 1, 15 (32.7%) patients were diagnosed with 26 complications, and in group 2 – 5 (16.6%) patients with 5 complications.Conclusions. The use of the developed surgical technique and the original fixator made it possible to increase the percentage of excellent and good treatment results from 84.5% to 92.7% and to reduce the number of complications associated with OWHTO from 32.7% to 16.6%.