Introduction
Medial opening wedge high tibial osteotomy (OWHTO) is a well-established treatment for medial compartment osteoarthritis of the knee, and the Lateral hinge fracture(LHF) is one of the complications after OWHTO. This study compared the detection rate of LHF after OWHTO on X-ray and CT.
Method
This study involved 46 Patients(24 male,22 female) undergoing OWHTO for primary medial compartment osteoarthritis at our hospital from July 2016 to September 2021.Patients who did not have a minimum 6-month of follow-up were excluded.The target weight-bearing point was determined at approximately 60% of the tibial plateau width from the medial border. LHF were evaluated on X-ray taken after surgery and CT taken the day after surgery according to the Takeuchi classification.
Results
Of the 46 knees, 6 knees(13%) were found on postoperative X-ray to have LHF.All 6 were classified as Type?:4,Type?:1,Type?:1. 24 knees(52.2%) were found on CT classified Type?:18,Type?:2,Type?:4.The mean open distance was significant difference between 8.6±1.8mm in the group without LHF and 10.4±1.9mm in the group with LHF(P=0.003).No significant defferences were found the correction loss and the amount of change in PTS in both group. P=0.303,P=0.535,respectively).
Conclusion
The LHF after OWHTO surgery was evaluated using CT and compared and discussed with X-ray. The incidence of LHF is as high as 52.2%, and early postoperative CT is useful. The risk of LHF increases as the mean open distance increases, so more careful surgical technique is required.