Steps to Restore Full Joint Motion with Total Knee Replacement

If you have limited knee motion and cannot straighten the leg fully, you may have what's called a knee flexion contracture (KFC). This condition occurs when a person avoids motion because it hurts. Total knee replacement (TKR) may help with this problem. The surgeon must release soft tissues and remove bone spurs to help restore full motion.

In this study, surgeons review all cases of KFC treated with TKR. They ask the question, How many steps are needed to correct the KFC? Four steps are evaluated. These include:

  • Step 1: Balancing the ligaments while removing all bone spurs and removing up to 2 mm of bone from the bottom of the femur (thighbone)
  • Step 2: Releasing the joint capsule from behind and lengthening the gastrocnemius (calf) muscle
  • Step 3: Removing even more bone (up to 4 mm) from the end of the femur, a process called resection
  • Step 4: Releasing the tight hamstring muscle

    There were 924 patients included in the study. Surgeons followed each step as listed in order one at a time until motion was restored in the operating room. Maximum knee extension was measured and recorded at the end of the surgery.

    The authors report that step one was enough to get full extension in 91 per cent of mild KFC. Adding step two increased this number to 98.6 per cent. The more severe the KFC, the more steps were needed to restore motion. Steps three and four were not needed in most cases.



    References: Johan Bellemans, MD, PhD, et al. Flexion Contracture in Total Knee Arthroplasty. In Clinical Orthopaedics and Related Research. November 2006. Number 452. Pp. 78-82.