Does the pre-operative status of the anterior cruciate ligament affect the outcomes following medial open-wedge high tibial osteotomy?

BACKGROUND

This study aimed to assess the morphological degeneration of the anterior cruciate ligament (ACL) through magnetic resonance imaging (MRI) and arthroscopy. It analyzed whether the pre-operative ACL status would affect the radiologic and clinical outcomes following medial open-wedge high tibial osteotomy (MOWHTO).

METHODS

A total of 150 knees were enrolled that underwent MOWHTO concomitant arthroscopic debridement for the treatment of varus osteoarthritis. Mean age was 56.1 ± 5.0 years and mean follow-up was 61.2 ± 21.4 months. The ACLs were staged based on MRI and arthroscopy. To exclude the influence of demographic factors on outcomes, the between-group differences were assessed. Radiologic evaluation included hip-knee-ankle angle, femorotibial angle, medial proximal tibial angle, posterior tibial slope angle, and Kellgren-Lawrence grade. Clinical evaluation included American Knee Society Score (AKSS) and knee joint range of motion (ROM).

RESULTS

The ACLs were classified into intact (75 knees, 50.0%), mucoid degeneration (59, 39.3%), chronic partial tear (10, 6.7%), and complete tear (six, 4.0%) according to MRI. They were also classified into four stages: normal (95 knees, 63.3%), abnormal (36, 24.0%), partial tear (13, 8.7%), and complete tear (six, 4.0%) according to arthroscopic appearance. There were no significant between-group differences in each variable. Changes in Kellgren-Lawrence grade did not show significant between-group differences. No significant between-group differences were observed in AKSS and ROM.

CONCLUSIONS

The pre-operative status of ACL did not influence the outcomes following MOWHTO at midterm follow-up.

LEVEL OF EVIDENCE

Level IV, case series.