Improvement in muscle strength after an anterior cruciate ligament injury corresponds with a decrease in serum...

Area of Science:

• Orthopedics
• Immunology
• Sports Medicine

Background:

• Anterior cruciate ligament (ACL) injuries are common and can lead to significant muscle weakness.
• The relationship between systemic inflammation and muscle function post-ACL injury requires further investigation.

Purpose of the Study:

• To determine if decreased serum cytokine concentrations correlate with improved muscle strength following an ACL injury.

Main Methods:

• Subjects undergoing ACL reconstructive surgery were divided into early (<21 days) and late (>=21 days) groups.
• Fasting blood samples were collected, and single-leg peak isometric force was tested on injured and non-injured limbs.

Main Results:

• The injured limb showed decreased peak isometric force in both early and late groups compared to the non-injured limb.
• The early group exhibited a greater force deficit and elevated serum levels of granulocyte macrophage colony-stimulating factor (GM-CSF), interleukin-6 (IL-6), and IL-13.
• Muscle weakness persisted in the late group but was less severe, paralleling reduced circulating cytokine concentrations.

Conclusions:

• Elevated serum cytokine concentrations are associated with increased muscle weakness in the early phase after ACL injury.
• A decrease in serum cytokines correlates with a reduction in muscle weakness in the later phase post-ACL injury.