Home > Uncategorized > Knee Extension Motion Post ACL-Reconstruction Is Associated with Knee Osteoarthritis Within 5-year Post-Surgery

Knee Extension Motion Post ACL-Reconstruction Is Associated with Knee Osteoarthritis Within 5-year Post-Surgery

Shelbourne KD, Urch SE, Gray T, Freeman H.  Loss of normal knee motion after anterior cruciate ligament reconstruction is associated with radiographic arthritic changes after surgery.  Am J Sports Med 2011 Oct 11. [Epub ahead of print]

PMID: 21989129

Note: This study examined risk factors for development of radiographic arthritic changes in the knee in those individuals who had ACL reconstruction performed.  The author’s found that knee extension/flexion range of motion measured with a standard goniometer was predictive of future development of knee arthritic changes within 5 years post-surgery.  Most important is that on small differences in knee extension/flexion range of motion compared to the uninjured side were predictive of future knee arthritic changes.  Individuals whose knee extension motion was more than 2-degrees less (this includes hyper-extension) and whose knee flexion motion was more than 5-degrees less than the uninjured side were at greater risk for radiographic arthritic changes in the ACL reconstructed knee.  This indicates how critical it is to achieve SYMMETRIC knee extension/flexion range of motion as part of the early rehabilitation goals following ACL reconstruction.

Clinical Implications: Individuals post ACL reconstruction are at greater risk for radiographic arthritic changes in the knee if their knee extension and flexion is not within 2 and 5-degrees, respectively of the uninjured knee.  Symmetrical knee extension/flexion should be a primary goal of the early rehabilitation process post-ACL reconstruction.  Failure to achieve symmetrical knee extension/flexion will increase the risk of early onset knee osteoarthritis within these individuals.  It is also important to continually monitor knee extension/flexion motion once symmetrical motion has been achieved.  This is especially important as previous research demonstrates that knee extension/flexion motion gains will often be lost several weeks of being achieved if continual focus on maintaining knee motion is not performed.  Thus, we should regularly re-assess knee motion post ACL reconstruction, even after symmetry with the uninjured side is achieved, to ensure that these gains are maintained and that risk of future knee osteoarthritis development is kept at a minimum.

BACKGROUND:  Meniscectomy and articular cartilage damage have been found to increase the prevalence of osteoarthritis after anterior cruciate ligament reconstruction, but the effect of knee range of motion has not been extensively studied.  HYPOTHESIS:  The prevalence of osteoarthritis as observed on radiographs would be higher in patients who had abnormal knee range of motion compared with patients with normal knee motion, even when grouped for like meniscal or articular cartilage lesions.  STUDY DESIGN: Cohort study; Level of evidence, 3.  METHODS: We prospectively followed patients at a minimum of 5 years after surgery. The constant goal of rehabilitation was to obtain full knee range of motion as quickly as possible after surgery and maintain it in the long term. Range of motion and radiographs were evaluated at the time of initial return to full activities (early follow-up) and final follow-up according to International Knee Documentation Committee (IKDC) objective criteria. A patient was considered to have normal range of motion if extension was within 2° of the opposite knee including hyperextension and knee flexion was within 5°. Radiograph findings were rated as abnormal if any signs of joint space narrowing, sclerosis, or osteophytes were present.  RESULTS:  Follow-up was obtained for 780 patients at a mean of 10.5 ± 4.2 years after surgery. Of these, 539 had either normal or abnormal motion at both early and final follow-up. In 479 patients who had normal extension and flexion at both early and final follow-up, 188 (39%) had radiographic evidence of osteoarthritis versus 32 of 60 (53%) patients who had less than normal extension or flexion at early and final follow-up (P = .036). In subgroups of patients with like meniscal status, the prevalence of normal radiograph findings was significantly higher in patients with normal motion at final follow-up versus patients with motion deficits. Multivariate logistic regression analysis of categorical variables showed that abnormal knee flexion at early follow-up, abnormal knee extension at final follow-up, abnormal knee flexion at final follow-up, partial medial meniscectomy, and articular cartilage damage were significant factors related to the presence of osteoarthritis on radiographs. Abnormal knee extension at early follow-up showed a trend toward statistical significance (P = .0544). Logistic regression showed the odds of having osteoarthritis were 2 times more for patients with abnormal range of motion at final follow-up; these odds were similar for those with partial medial meniscectomy and articular cartilage damage.  CONCLUSION: The prevalence of osteoarthritis on radiographs in the long term after anterior cruciate ligament reconstruction is lower in patients who achieve and maintain normal knee motion, regardless of the status of the meniscus.

Categories: Uncategorized
  1. No comments yet.
  1. No trackbacks yet.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: