Radiographic evidence of osteoarthritis five years after anterior cruciate ligament reconstruction is significantly more likely in patients with limited range of motion—even by just a few degrees—in the operated knee, according to research presented at the AAOS meeting.
Investigators from the Shelbourne Knee Center in Indianapolis analyzed 780 patients at least five years (mean 10.5 years) following ACL reconstruction. Normal extension was defined as within 2° of the contralateral limb; normal flexion was defined as within 5° of the contralateral limb. Radiographic findings corresponding to a Kellgren-Lawrence grade of 2 or higher in any compartment were considered abnormal.
Patients with normal ROM were significantly more likely to have normal radiographs than those with abnormal ROM (71% vs 55%). The results are consistent with those published by the same researchers in the March 2009 issue of the American Journal of Sports Medicine, in a study of 502 patients at least 10 years post-ACL reconstruction. In that study, abnormal radiographs were seen in 71% of patients with abnormal ROM and just 29% of those with normal ROM.