The effect of kinesiophobia (fear of movement) following an anterior cruciate ligament injury (ACL) has recently received greater attention. However, the relationship between kinesiophobia and peak vertical ground reaction force (VGRF) in ACL reconstructed (ACLR) and deficient (ACLD) individuals has not been investigated.
Methods: Forty male participants (20 ACLR and 20 ACLD), 24 months post ACL injury, who had completed post injury/operative rehabilitation, participated in this cross-sectional the study. Participants completed a drop vertical landing task on force plate while the VGRF recorded. Participants also completed the TSK-11 (kinesiophobia) questionnaire.
Results: Associations between peak VGRF with the TSK scale were made with Pearson correlation coefficients with significant relationships defined as p≤0.05. The average peak VGRF was 2.67 ± 0.28 and 2.68 ± 0.17 (mean±SD) %bodyweight and TSK value was 33.45 ± 4.6 and 31.60 ± 3.40 (mean±SD) for ACLD and ACLR groups respectively. There was a significant negative association between poorer responses on the TSK scale and peak VGRF in ACLD group (r=-0.58, p=0.007) but not in ACLR group (r=-0.31, p=0.17).
Conclusion: We found greater kinesiophobia to be associated with a lower peak VGRF in the ACLD group during landing task. It seems that ACLD individuals unload their injured limb because of fear of movement. These results suggest that in ACLD individuals with high kinesiophobia, cognitive training should be incorporated into rehabilitation program to improve landing mechanics. Future studies are needed to assess if these relationships could play role in developing osteoarthritis over years.