SLR - June 2021 - Kalli E. Mortenson
Reference: Hu Y, Yue C, Li X, Li Z, Zhou D, Xu H, Zhang N. A Novel Medial Malleolar Osteotomy Technique for the Treatment of Osteochondral Lesions of the Talus. Orthopaedic Journal of Sports Medicine. 2021 Mar 23; 9(3), 1-7.Level of Evidence: Case series, IV
Scientific Literature Review
Reviewed By: Kalli E. Mortenson, DPM
Residency Program: Beaumont Health Wayne, Wayne, MI
Podiatric Relevance: Osteochondral lesions of the talus are common articular defects seen after ankle joint trauma. Surgical treatment options vary greatly depending on size, stage and location of the osteochondral defect. Smaller sized lesions may easily be visualized and treated arthroscopically, however, larger sized lesions often require either medial or lateral malleolar take down in order to adequately expose the area for correction. Previously reported chevron and step-cut medial malleolar osteotomies have been shown to have a less than ideal malunion rate and displacement of the osteotomy leading to accelerated ankle joint arthritis in addition to potential harm to the posterior tibial tendon. This study reviews a new partial step-cut technique to the medial malleolus involving the anterior one-third to two-thirds with goals to avoid injuries posterior to the medial malleolus.
Methods: A level IV case series was performed evaluating 18 patients (19 ankles total) who had underwent a partial step-cut medial malleolar osteotomy for treatment of an OCD lesion of the talus. Medial malleolar osteotomies were fixated with either two compression screws or a combination of 1 compression screw with a buttress plate. Clinical outcomes were measured post operatively by evaluating the visual analog scale (VAS) and the American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale. Post-operative radiographs were obtained at six, eight and 12 weeks and again at final follow up to evaluate for osseous union and correct alignment.
Results: All cases achieved osseous union by 12 weeks post-op with a mean healing time of 7.3 weeks. At final 24 month follow up all cases showed a smooth articular surface of the tibial plafond at the level of the malleolar osteotomy site. Closer evaluation of the radiographs revealed displacement of the osteotomy in four cases in which there was a mean displacement of 1 millimeter proximally and 0.3 millimeters medially. There were no statistically significant differences in osseous healing time between the two types of fixation of the medial malleolus. VAS and AOFAS scores improved significantly in all patients. There were no reported hardware failures, intra-operative tendon injuries, ankle joint stiffness or other complications noted.
Conclusions: A partial step-cut medial malleolar osteotomy may be utilized in most medially located OCD lesions of the talus that require a larger window of visualization for correction. The partial step-cut medial malleolar osteotomy provides adequate exposure of the defect while also preserving structures posterior to the medial malleolus. With this technique surgeons do not need to visualize and/or deliberately protect structures posterior to the medial malleolus, leading to a shorter time to perform the osteotomy thus decreasing operating time. The partial step-cut osteotomy additionally provides intrinsic stability in comparison to previously reported osteotomy techniques with a satisfactory rate of osseous union allowing earlier rehabilitation for patients post-operatively.