Management principle and clinical suggestions of osteotomy gap of opening wedge high tibial osteotomy

To summarize the management principle and clinical suggestions of the osteotomy gap of opening wedge high tibial osteotomy (OWHTO). The related literature of the osteotomy gap of OWHTO in recent years was reviewed, summarized, and analyzed. Delayed union and non-union of the osteotomy gap are main complications of OWHTO. Tomofix plate, as locking steel plate, has the characteristics of angular stability and can better maintain the stability of the osteotomy gap, promote bone healing, and avoid loss of correction. There are some treatment options for the osteotomy gap site, such as, without bone, autologous bone graft, allogeneic bone graft, bone substitute materials graft, and augment factor graft to enhance bone healing. When the osteotomy gap is less than 10 mm, it achieves a good outcome without bone graft. For the obesity, lateral hinge fracture, large osteotomy gap, or correction angle more than 10°, the bone graft should be considered. In cases whose osteotomy gap is nonunion or delayed union, the autol