High Tibial Medial Opening Wedge Osteotomy and Ligament Reconstruction for Varus Angulated Anterior Cruciate Ligament Deficient Knee

Abstract Background: Chronic anterior cruciate ligament (ACL) deficiency is associated with knee instability and development of chronic varus malignment and medial compartment oste-oarthritis (OA). ACL reconstruction (ACLR) is performed with high success rate in most patients. However, patients presenting with chronic anterior cruciate ligament deficient (ACLD) and varus angulated knees represent a challenge to orthopedic surgeons, as ACLR addresses anterior knee insta-bility alone, however, it fails to correct knee malignment, and thus, fails to impact the progression of OA. Aim of Study: The aim of this study is to prospectively assess the effectiveness of management of varus angulated-ACL deficient knees by simultaneous arthroscopic ACL reconstruction and medial opening wedge high tibial osteotomy (HTO) using locked plate and synthetic bone graft. The Lysholm knee scoring systems are used to assess the patients. Clinical outcomes are assessed preoperatively and at 20 months post-operatively. Patients and Methods: This prospective study included 20 patients. The patients' age ranged between 18-40 years, all were males, most injuries were sports injury and all of them suffered from chronic ACL insufficiency with varus deformity. All patients underwent simultaneous arthroscopic ACL reconstruction and medial opening wedge high tibial osteotomy (HTO) using locked plate and synthetic bone graft. Clinical outcomes were assessed with the Lysholm knee scoring system, pivot shift test, anterior drawers test and Lachman test; and KT-1000 arthrometer. Preoperatively, MRI and X-ray were used for ACL diagnosis and for measuring degree of varus, the standing hip knee ankle angle (HKA°, alignment), posterior tibial slope (PTS), lateral joint opening and degree of arthritis. Postoperative X-rays were done to evaluate deformity correction, union, fixation devices and tunnels position. All patients were followed-up at 2 weeks and at 1, 3, 6, 12 and 20 months postoperatively. Clinical outcomes were assessed preoperatively and at 20 months post-operatively.
Results: All clinical scores improved significantly after surgery. 75% of patients had excellent knee function and 25% had good knee function according to Lysholm score. The anterior laxity of the patients' knee was also improved after surgery as 90% of patients were considered normal or near normal according to KT-1000 arthrometer measurement. Varus deformity was also improved after surgery asthe mean HKA angle improved from 10.65°  varus to 0.6°  varus; with 60% of the patients showed normal alignment. Also, postoperatively all patients had mild lateral joint opening and the posterior tibial slope was slightly increased after surgery (from 6.06°  to 6.32°). 80% of the patients returned to their preinjury level of activity at the end of the follow-up period. Postoperative complications were few and mild, and were easily managed. Conclusion: It could be concluded that performing simul-taneous arthroscopic ACL reconstruction and medial opening wedge high tibial osteotomy (HTO) using locked plate and synthetic bone graft was effective for obtaining a satisfactory correction angle, good clinical outcomes and lower compli-cation rate.