By Jordana Bieze Foster
After unilateral anterior cruciate ligament reconstruction (ACLR), mechanical loading in the affected limb is associated with altered patterns of collagen metabolism, according to research from the University of North Carolina at Chapel Hill that could help explain the development of knee osteoarthritis in patients with a history of ACLR.
The investigators analyzed concentrations of collagen type II cleavage product (C2C), a marker for collagen breakdown, and collagen type II C-protopeptide (CPII), a marker for collagen synthesis, in blood samples from 19 patients with a history of primary unilateral ACLR who had returned to unrestricted activity. They also assessed peak vertical ground reaction force (vGRF) and linear vGRF loading rate as the patients walked at a self-selected speed.
Higher peak vGRF in the injured limb was associated with a lower ratio of C2C to CPII, suggesting less collagen turnover. Serum concentrations of the collagen metabolism markers, however, were not significantly associated with vGRF or linear vGRF loading rate.
The findings were epublished in December by the American Journal of Sports Medicine.
Pietrosimone B, Blackburn JT, Harkey MS, et al. Greater mechanical loading during walking is associated with less collagen turnover in individuals with anterior cruciate ligament reconstruction. Am J Sports Med 2015 Dec 18. [Epub ahead of print]