A longitudinal study of orthopaedic outcomes for severe factor-VIII-deficient haemophiliacs. The Orthopaedic Outcome Study Group.

Abstract

Arthropathy is the major cause of morbidity in haemophilia. In an attempt to establish optimal therapeutic regimens for persons with haemophilia, we hypothesized that no direct relationship exists between increasing factor dosage and orthopaedic outcomes over time. A longitudinal uncontrolled 6 year study was carried out. Ankles, knees and elbows of patients were studied using physical and X-ray examination scores. Bleeding episodes and treatment regimens were determined. The amount of time lost from work and school, as well as days in hospital, was also monitored. Twenty-one international haemophilia centres were used to accrue and follow patients over the 6 year period. Severe (< 1%) factor VIII deficient patients under the age of 25 without inhibitors were recruited into the study. The status of the six major joints of these patients were measured annually for mobility. X-ray evaluation of these joints was carried out at the beginning and end of the study. Using a World Federation of Haemophilia joint and X-ray score, stability, progression or regression of arthropathy was evaluated. Physical and X-ray examination scores increased significantly with age, and the number of joint bleeds were significant in determining the delta score. Approximately 10% of patients entered with all six joints normal. Of these, 50% remained so. Year-long prophylaxis significantly reduced the rate at which joints deteriorate both on physical (P = 0.02) and X-ray examination (P = < 0.001). Patients on prophylaxis had significantly fewer days lost from work or school, as well as fewer days spent in hospital (P = < 0.01). Higher doses of factor per se do not necessarily produce improved orthopaedic outcomes. However, full time prophylaxis is likely to produce the best orthopaedic outcome. The most critical factor for a good orthopaedic outcome is the reduction of joint bleeds.