The factors affecting the timing of bone union after closing-wedge high tibial osteotomy

Abstract

Objective: Closing-wedge high tibial osteotomy (CWHTO) for medial osteoarthritis of the knee is one of the effective osteotomy methods, especially for patients with cartilage damage of the patellofemoral joint, flexion contracture, and requiring a large correction angle.While the bone union at the osteotomy site is finally obtained after CWHTO, there are often differences in the period of the bone union. The purpose of the present study is to investigate the factors affecting the timing of bone union after CWHTO.

Methods: 16 cases of CWHTO were included; they were performed by the same surgeon using precisely the same implants. Among 16 cases in the present study, nobody used low-intensity pulsed ultrasound (LIPUS) within three months after the operation. The patients were divided into two Groups using Plane X-ray and CT within three months after surgery: Group D (8 knees; bone healing was not seen at all) and Group E (8 knees; bone healing was seen).

Results: There were no significant differences in mean age between the two groups, but body mass index (BMI) and bone mineral density (BMD) were significantly higher in Group D (p < 0.05).

Conclusion: The present study suggests that BMI and BMD may affect the timing of bone union after CWHTO.

Background: Closing-wedge high tibial osteotomy (CWHTO) for medial osteoarthritis of the knee is one of the effective osteotomy methods. The frequency of selecting CWHTO in our hospital in Japan is high, especially for patients with cartilage damage of the patellofemoral joint, flexion contracture, and requiring a large correction angle. On the other hand, while the bone union at the osteotomy site is obtained with both procedures, there are often differences in bone union time for CWHTO compared to Opening-wedge high tibial osteotomy (OWHTO). This difference might affect the early clinical outcome of the operations. We hypothesized that there is some factor to affect bone healing of CWHTO for individual patients.

Purpose: To investigate the factors affecting the timing of bone union after CWHTO.

Keywords: BMD; BMI; Bone union timing; Closing-wedge high tibial osteotomy(CWHTO); Delayed union; Risk factor.

Fig. 1

a) (b) (c) (d) (e). a) the plane X-ray in the Anteroposterior view before the operation b) the plane X-ray in the Anteroposterior view after the operation c) the plane X-ray in the Anteroposterior view 3 months after the operation d) the sagittal section of the 3months postoperative CT e) the sagittal section of the 10months postoperative CT.

Fig. 2

a) (b) (c) (d). a) the plane X-ray in the Anteroposterior view before the operation b) the plane X-ray in the Anteroposterior view after the operation c) the plane X-ray in the Anteroposterior view 3 months after the operation d) the sagittal section of the 3months postoperative CT.