Valgus-producing high tibial osteotomy (HTO) is a well-accepted treatment modality in active patients with varus malalignment and symptomatic medial unicompartmental osteoarthritis (OA) of the knee. One of the key factors for long-term success of the osteotomy is the achievement of an even distribution of the mechanical load on the knee joint by obtaining an ideal alignment of the lower-extremity mechanical axis. Proper surgical techniques are very important, and lateral closing wedge proximal tibial valgus osteotomy (CWO) is highly effective in achieving the desired overcorrection of 3° to 7° of valgus.
The major steps of CWO are (1) preoperative planning, in which the frontal plane varus knee deformity is assessed on a standard whole-leg radiograph; (2) a transverse anterolateral incision from the tubercle toward the posterior aspect of the proximal part of the fibular head; (3) exposure and snaring of the common peroneal nerve; (4) resection of the anterior aspect of the proximal part of the fibular head; (5) use of a calibrated slotted wedge resection guide to perform the osteotomy proximal to the tuberosity under fluoroscopic guidance; (6) removal of an osseous wedge and closure of the osteotomy site, with the medial opposite cortex acting as a hinge; and (7) fixation of the osteotomy site with two step staples. Complications (e.g., nonunion, deep infection, and peroneal neuropathy) are rare. At follow-up, CWO has been shown to improve knee function and reduce pain. Male patients with early-onset knee OA have an almost ten times lower probability of failure of a CWO than women with more degenerative disease. The survival rate, with knee replacement as the end point, is approximately 75% at ten years following CWO. CWO postpones primary total knee arthroplasty (TKA) for a median of seven years, and there is low-quality evidence that osteotomy does not compromise subsequent knee replacement.
Note: The three graphs showing survival rates after CWO in Video 14 (Results) were reproduced, with permission, from: van Raaij TM, Brouwer RW, de Vlieger R, Reijman M, Verhaar JA. Opposite cortical fracture in high tibial osteotomy: lateral closing compared to the medial opening-wedge technique. Acta Orthop. 2008 Aug;79(4):508-14.
Published outcomes of this procedure can be found at: Cochrane Database Syst Rev. 2014 Dec 13;12:CD004019, Acta Orthop. 2008 Apr;79(2):230-4, and J Bone Joint Surg Am. 2014 Sep 3;96(17):1425-32.
Disclosure: None of the authors received payments or services, either directly or indirectly (i.e., via his or her institution), from a third party in support of any aspect of this work. None of the authors, or their institution(s), have had any financial relationship, in the thirty-six months prior to submission of this work, with any entity in the biomedical arena that could be perceived to influence or have the potential to influence what is written in this work. Also, no author has had any other relationships, or has engaged in any other activities, that could be perceived to influence or have the potential to influence what is written in this work. The complete Disclosures of Potential Conflicts of Interest submitted by authors are always provided with the online version of the article.
- Copyright © 2015 by The Journal of Bone and Joint Surgery, Incorporated