Intraoperative adjustment of alignment under valgus stress reduces outliers in patients undergoing medial opening-wedge high tibial osteotomy.

Kim, Man; Son, Jong; Koh, In; Bahk, Ji; In, Yong; Kim, Man Soo; Son, Jong Min; Koh, In Jun; Bahk, Ji Hoon

<bold>Introduction: </bold>A considerable percentage of outliers with under- or over-correction continue to be reported despite precise preoperative planning and cautious intraoperative correction of lower limb alignment in medial opening-wedge high tibial osteotomy (MOWHTO). The purpose of this study was to determine whether our novel technique for the intraoperative adjustment of alignment under valgus stress reduces the number of outliers in patients undergoing MOWHTO compared to the conventional technique, which corrects alignment according to the cable method only.<bold>Materials and Methods: </bold>One hundred seventeen consecutive knees were enrolled in this case-control study. The first 52 knees (51 patients) were corrected in accordance with preoperative plans using the Dugdale method with modification with an intraoperative cable (group 1). In the other 65 knees (60 patients), the angle was corrected using the Dugdale method and limb alignment was adjusted using the intraoperative cable technique by applying valgus stress to the knee joint (group 2). The postoperative weight bearing line ratios and mechanical axis of the lower limb were compared at postoperative one year. Each knee was evaluated according to the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score preoperatively and at postoperative one year.<bold>Results: </bold>A significant reduction in the number of outliers was seen in group 2 compared to group 1 (group 1 = 48.1%, group 2 = 9.2%, p < 0.001). Nineteen of 52 knees (36.5%) were under-corrected in group 1, whereas 6 of 65 knees (9.2%) were under-corrected in group 2 (p < 0.001). Six of 52 knees (11.6%) were over-corrected in group 1, whereas 0 of 65 knees (0.0%) were over-corrected in group 2 (p = 0.005). At one -year after operation, group 2 showed significantly lower WOMAC score than group 1 (p = 0.014).<bold>Conclusions: </bold>Intraoperative adjustment of alignment under valgus stress significantly reduced the number of outliers compared to a technique that corrected alignment using the cable method in patients undergoing MOWHTO.<bold>Level Of Evidence: </bold>Level III, retrospective comparative study.

LIGAMENT injuries; TIBIA surgery; OSTEOTOMY; ORTHOPEDIC surgery; SURGERY; KNEE physiology; KNEE surgery; QUESTIONNAIRES; SURGICAL complications; TREATMENT effectiveness; CASE-control method; WEIGHT-bearing (Orthopedics)

Archives of Orthopaedic & Trauma Surgery, 2017, Vol 137, Issue 8, p1035

0936-8051

Academic Journal

10.1007/s00402-017-2729-4