Early Completion of Radiographic Bone Union With Rare Complications After Inverted V-Shaped High Tibial Osteotomy...

Recently, the inverted V-shaped high tibial osteotomy (iVHTO) procedure fixed with a locking compression plate (LCP) has attracted notice as a useful surgical option for medial osteoarthritic knees with severe varus deformity. However, no studies have clarified how bone healing at the osteotomy site progresses after this surgery or when bone union is completed.

To clarify how bone healing at the osteotomy site progresses after the iVHTO procedure fixed with an LCP and when bone union is completed.

Case series; Level of evidence, 4.

A total of 109 knees in 96 patients who underwent this procedure were followed up for a minimum of 24 months after surgery. Radiographs were obtained at 5, 8, 12, 16, 20, 24, 36, 52, and 104 weeks after surgery. In addition, computed tomography (CT) imaging was performed at 5, 12, and 24 weeks. Three experienced surgeons independently observed the radiographs and CT images. The radiographic union score for tibial fractures was used to quantitatively determine the bone union time. The relationship between bone healing and clinical outcome measures was analyzed.

The progression of bone healing at the osteotomy site after this iVHTO procedure could be classified into 3 types: type 1 (direct bone healing), type 2 (indirect bone healing), and type 3 (delayed bone healing). The incidences of types 1, 2, and 3 were 75.2%, 18.3%, and 6.4%, respectively. The mean time required to complete bone union was 10.6 weeks in type 1 knees, 16.8 weeks in type 2 knees, and 22.3 weeks in type 3 knees, showing significant differences among the 3 types (P < .001). The mean overall bone union time was 12.5 weeks in 108 knees, excluding 1 knee that required additional surgery. The overall rate of major complications was 9.2%, which included only cases of delayed union. The complication rate was significantly different among the 3 types (P < .001).

The fact that type 1 bone healing occurred in 75.2% of knees is a unique feature of iVHTO fixed with an LCP. Early completion of bone union with rare complications is one of the clinical advantages of this iVHTO procedure.