Leon Schooff (Freiburg i. Br.; Basel / CH), Dr.sc.med.des Simon Herger (Basel / CH), Dr. Corina Nüesch (Basel / CH), Dr. Wolfgang Wirth (Freilassing; Salzburg / AT), PD Dr. med. Florian B. Imhoff (Basel / CH), PD Dr. Christian Egloff (Basel / CH), Prof. Annegret Mündermann (Basel / CH)
Abstract-Text (inkl. Referenzen und Bildunterschriften)
Introduction
Models for the development of post-traumatic knee osteoarthritis (OA) after ACL injury suggest that gait biomechanics may play a role in cartilage degeneration in addition to structural, biological and neuromuscular factors.1 To date, the relationship between laminar cartilage composition (T2 time) and gait biomechanics in young adults after an ACL injury is unknown.
Aim
To investigate the relationship between T2 time and ambulatory load in young healthy subjects with or without previous ACL injury.
Methods
20 young adults 2-10 years after ACL injury (6m/14f, 26.1±3.1 years, 23.5±2.6 kg/m2) and 20 young healthy controls (9m/11f, 26.1±3.0 years, 22.7±1.6 kg/m2) were included. T2 times were measured in the deep zone in the medial and lateral femorotibial cartilage from MRI. The external knee flexion moment during walking was calculated using motion capture and inverse dynamics (CGM 2.3). Pearson correlations between absolute T2 times and peak knee flexion moment were calculated for both legs in ACL-patients and the left leg in controls (P<0.05).
Results
Medial compartment T2 of the ACL injured legs correlated strongly with the peak knee flexion moment (R=0.520, P=0.019), whereas no correlations for the contralateral legs and the healthy legs were found (Fig.1). For lateral compartment T2 of the ACL injured legs (R=0.160, P=0.491) and contralateral legs (R=0.230, P=0.339) the correlation was weak, while there was no correlation in the healthy control legs.
Summary
Elevated cartilage T2 represent worse cartilage composition. The higher medial compartment T2 of the ACL injured leg with higher peak knee flexion moments suggest that cartilage composition in the medial compartment may be susceptible to higher ambulatory loads after an ACL injury. To prevent post-traumatic OA, gait intervention strategies that reduce peak knee loading should be considered and further researched.
Funding: SNF#184912
1Wang et al. Arthritis Res Ther 2020