Patients who had pre-emptive treatment of pain with a cyclooxygenase-2 (COX 2) inhibitor before knee replacement surgery had less pain and vomiting after the surgery, needed fewer opioids, slept better, had better knee flexion, and needed less physical therapy. The randomised controlled trial was reported by Dr Asokumar Buvanendran and colleagues at Rush-Presbyterian-St Luke's Medical Center, Chicago (JAMA 2003;290: 2411-8).
Knee replacement is among the most painful of operations, Dr Buvanendran said. The 70 patients, aged 44 to 77 years, were assigned to placebo treatment or to treatment with 50 mg of oral rofecoxib 24 hours before surgery, another 50 mg an hour or two before surgery, 50 mg daily for five days after surgery, and 25 mg daily for the next eight days. All patients were given epidural anaesthesia and self controlled analgesia after surgery.
Range of motion is an important outcome measure after knee replacement. The degree of knee flexion needed for climbing stairs is 83°, for descending stairs 90°, and for tying shoelaces 106°. At discharge, patients in the rofecoxib group had 84.2° of active flexion and patients in the placebo group had 73.2°. One month after surgery the figures were 109.3° and 100.8° respectively.
Dr Buvanendran said that the improvement meant an increase in satisfaction among patients, a quicker return to work or usual activities, and a reduction in the costs of physical therapy.