Predicting How Far Your New Knee Joint Will Bend

People in need of a new knee joint often wonder how far their knee will bend after surgery. Researchers have new insights. They found that a major influence on how far you can bend your knee after knee joint replacement is the amount of knee bend you have before surgery.

These researchers studied 4,727 knees before, during, and after knee joint replacement. They measured the amount of bend (flexion) in each patient at six months and one, three, five, and seven years after knee replacement. Increases in knee motion stopped after three years. This finding supports results from other studies.

No matter what kind of arthritis the patient had or how badly the knee was lined up, the amount of knee flexion before surgery was still the number one way to tell how much knee bend would be present after the surgery. Patients with less than 90 degrees of knee bend before surgery were more likely to have a poor result.

Know that if you're in need of a new knee joint, you have an edge in telling how far your knee will bend after surgery. This research makes it clear. A powerful predictor of how far a knee will bend after knee joint replacement depends on how far the knee bends before surgery.



References: Merrill A. Ritter, MD, et al. Predicting Range of Motion after Total Knee Arthroplasty. In The Journal of Bone and Joint Surgery. July 2003. Vol. 85-A. No. 7. Pp. 1278-1285.