What is the best way of assessing outcome after total knee replacement?

The effect of bracing on varus gonarthrosis

BACKGROUND

The purpose of this study was to compare a custom-made valgus-producing functional knee (unloader) brace, a neoprene sleeve, and medical treatment only (control group) with regard to their ability to improve the disease-specific quality of life and the functional status of patients who had osteoarthritis in association with a varus deformity of the knee (varus gonarthrosis).

METHODS

The study design was a prospective, parallel-group, randomized clinical trial. Patients who had varus gonarthrosis were screened for eligibility. The criteria for exclusion included arthritides other than osteoarthritis; an operation on the knee within the previous six months; symptomatic disease of the hip, ankle, or foot; a previous fracture of the tibia or femur; morbid obesity (a body-mass index of more than thirty-five kilograms per square meter); skin disease; peripheral vascular disease or varicose veins that would preclude use of a brace; a severe cardiovascular deficit; blindness; poor English-language skills; and an inability to apply a brace because of physical limitations such as arthritis in the hand or an inability to bend over. Treatment was assigned on the basis of a computer-generated block method of randomization with use of sealed envelopes. The patients were stratified according to age (less than fifty years or at least fifty years), deformity (the mechanical axis in less than 5 degrees of varus or in at least 5 degrees of varus), and the status of the anterior cruciate ligament (torn or intact). The patients were randomly assigned to one of three treatment groups: medical treatment only (control group), medical treatment and use of a neoprene sleeve, or medical treatment and use of an unloader brace. The disease-specific quality of life was measured with use of the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and the McMaster-Toronto Arthritis Patient Preference Disability Questionnaire (MACTAR), and function was assessed with use of the six-minute walking and thirty-second stair-climbing tests. The primary outcome measure consisted of an analysis of covariance of the change in scores between the baseline and six-month evaluations.

RESULTS

One hundred and nineteen patients were randomized. The control group consisted of forty patients (thirty-one men and nine women; mean age, 60.9 years); the neoprene-sleeve group, of thirty-eight patients (twenty-seven men and eleven women; mean age, 58.2 years); and the unloader-brace group, of forty-one patients (twenty-eight men and thirteen women; mean age, 59.5 years). Nine patients withdrew from the study. At the six-month follow-up evaluation, there was a significant improvement in the disease-specific quality of life (p = 0.001) and in function (p< or =0.001) in both the neoprene-sleeve group and the unloader-brace group compared with the control group. There was a significant difference between the unloader-brace group and the neoprene-sleeve group with regard to pain after both the six-minute walking test (p = 0.021) and the thirty-second stair-climbing test (p = 0.016). There was a strong trend toward a significant difference between the unloader-brace group and the neoprene-sleeve group with regard to the change in the WOMAC aggregate (p = 0.062) and WOMAC physical function scores (p = 0.081).

CONCLUSIONS

The results indicate that patients who have varus gonarthrosis may benefit significantly from use of a knee brace in addition to standard medical treatment. The unloader brace was, on the average, more effective than the neoprene sleeve. The ideal candidates for each of these bracing options remain to be identified.

The development and evaluation of a disease-specific quality of life measurement tool for shoulder instability. The Western Ontario Shoulder Instability Index (WOSI)

The purpose of this study was to develop a valid, reliable, and responsive disease-specific quality of life measurement tool for patients with shoulder instability. Development included 1) identification of a specific patient population; 2) generation of issues specific to the "disease" ("items") from reviewing the literature, interviewing health caregivers, and interviewing patients representing all demographics, disease type and severity, and treatments; 3) item reduction using patient-generated frequency-importance products and correlation matrices; and 4) pretesting the prototype instrument on 2 groups of 10 patients. The final instrument, the Western Ontario Shoulder Instability Index, has 21 items representing 4 domains. The instrument attributes (validity, reliability, and responsiveness) were evaluated. Construct validation demonstrated that this index correlated predictably with other measures. Reliability was very high at 2 weeks and 3 months, and the index was more responsive (sensitive to change) than five other shoulder measurement tools (the Disabilities of the Arm, Shoulder and Hand scale; The American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form; the UCLA Shoulder Rating Scale; the Constant Score; and the Rowe Rating Scale), a global health instrument (the SF12), and range of motion. Since the patient's perception of changes in health status is the most important indicator of the success of a treatment, we suggest that this measurement tool be used as the primary outcome measure to evaluate treatments in this patient population, although it can also be used for monitoring patients' progress in clinical practice.