Introduction
The purpose of this study was to investigate whether generalized joint laxity (GJL) affects the postoperative alignment and clinical outcomes of Medial opening-wedge high tibial osteotomy (MOWHTO).
Methods
A 198 patients was divided into two groups according to absence or presence of GJL. GJL was measured using the Beighton and Horan criteria, and a score of 4 or more out of 9 was defined as GJL. A weight bearing line (WBL) ratio of 55–70% was considered an acceptable postoperative lower limb alignment range. The WBL ratio was investigated before and 2 years after surgery, and the Western Ontario McMaster University Osteoarthritis Index scale score (WOMAC) was evaluated for patient-reported outcomes (PRO) of MOWHTO.
Results
There were 147 (73.7%) patients in the non-GJL group and 51 (26.3%) in the GJL group. Preoperatively, there was no difference in hip-knee-ankle (HKA) angle or WBL ratio (all p>0.05). At 2 years postoperatively, the GJL group showed significantly higher HKA angle and WBL ratio than the non-GJL group (all p<0.05). There was a significant difference in the distribution ratio of under-, normo-, and overcorrection patients between the non-GJL group (23.8%, 72.1%, and 4.1%, respectively) and GJL group (15.7 %, 70.6 %, and 13.7%, respectively) (p<0.05). There were no differences between the two groups in preoperative and postoperative WOMAC scores (all p>0.05).
Conclusion
The GJL significantly affected postoperative overcorrection of alignment following MOWHTO. However, there was no significant difference in PRO between the patients with and without GJL after MOWHTO until 2 years.