Knee joint forces during functional exercises
During knee rehabilitation, the challenge is to protect the injured joint surfaces from excessive force while providing adequate training stimuli for the quadriceps.
This study graded knee joint loads during squat, lunges, single leg hop, stairs, standing up and down and gait.
Tibiofemoral (TF) contact forces (CF's) were equal or lower than gait for sit down, stand up, stairs and squatting and could be useful during early TF rehabilitation.
3D-motion analysis data of 15 healthy adults was acquired and processed using musculoskeletal modeling to calculate the forces in different knee joint compartments.
Force distribution varied between exercises. Forward lunges resulted in more medial loading compared to lateral loading, whereas the opposite was found during squat and sideward lunge. With increased knee flexion, more force was imposed on the posterior femoral condyles and should be restricted In instances of lesions or repair surgery to this compartment.
All exercises imposed higher patellofemoral (PF) CF's compared to gait and should be gradually introduced for those with PF lesions or pain.
The results suggest that with careful selection of exercises, forces on an injured zone of the knee joint can be reduced. Surgical intervention and tissue repair status can also be considered in the selection of exercises.
The results may be different in patients who may adapt movement patterns to avoid pain and therefore influence knee loading.
> From: Van Rossom et al., J Orthop Sports Med (2018-02-20 19:32:45) (Epub ahead of print). All rights reserved to Journal of Orthopaedic and Sports Physiotherapy. Click here for the online summary.