Acta Radiologica 43 (2002) 528–532 Copyright C Acta Radiologica 2002 Printed in Denmark ¡ All rights reserved ACTA RADIOLOGICA 0284-1851 ASSOCIATION BETWEEN JOINT BLEEDS AND PETTERSSON SCORES IN SEVERE HAEMOPHILIA K. F 1,2 , B. A.  H 3 , J. G.   B 2,3 , D. E. G 3 and H. M.   B 2 1 Department of Paediatrics, 2 The Van Creveldkliniek and 3 The Julius Center for General Practice and Patient Oriented Research, University Medical Centre Utrecht, The Netherlands. Abstract Purpose: To assess and quantify the association of haemophilic arthropathy, Key words: Haemophilia, measured by the radiological Pettersson score, with the number of joint bleeds arthropathy; haemarthrosis, suffered by the patient. Pettersson scores; prophylaxis. Material and Methods: In order to quantify the effect of the cumulative num- ber of joint bleeds on the Pettersson score, a study was performed using 295 Correspondence: Kathelijn Fischer, Pettersson scores obtained in 117 patients with severe haemophilia. The patients Van Creveldkliniek (HP C01.452), were born between 1965 and 1994, and had no history of inhibitors. The num- University Medical Centre Utrecht, ber of joint bleeds was determined annually from the entry in the clinic and PO Box 85500, NL-3508 GA onwards. The localization of bleeds was not assessed. The patients entered the Utrecht, The Netherlands. clinic at a median age of 3.6years, and received intermediate dose prophylaxis, FAX π 31 30 2505438. starting at a median age of 5.3years. Evaluation of 1643 treatment years showed a mean of 6.8 joint bleeds/year. Pettersson scores were obtained at a mean age Accepted for publication 15 May of 15.9years (range 1.7–32.9) and had a median value of 4 points (range 0–50). 2002. Results and Conclusion: The Pettersson scores began to rise after the age of 5years and increased with one point for every 13 joint bleeds (95% confidence interval 11–15). No evidence was found of ‘autonomous’ progression of Petters- son scores, independent of bleeds. Patients with severe haemophilia have a clotting fac- tor VIII or IX activity of less than 1% of normal ( 0.01IU/ml). As a consequence, they suffer spon- taneous and traumatic bleeds, especially in the el- bows, knees, and ankles. Over time, these repeated joint bleeds lead to haemophilic arthropathy (3, 17). Fortunately, effective replacement therapy with clotting factor products has been available since the 1960s (16). Moreover, prophylactic treatment was introduced in the form of regular infusions of clot- ting factor concentrate in order to prevent bleeds (13). Since then, it has been shown that intensive prophylaxis in high doses can almost completely prevent the occurrence of joint bleeds (10, 11). Lower dosage prophylactic regimens result in a slightly higher bleeding frequency (5, 19). Unfortu- nately, clotting factor products are very expensive 528 and available only in limited quantities. As a conse- quence, the current question is not whether to treat these patients with prophylaxis, but how intensively. Should one try to attempt to prevent all joint bleeds with high-dose prophylaxis, or can we use lower dosages and accept a limited number of joint bleeds? As one of many steps towards answering this ques- tion, it is important to quantify the association be- tween joint bleeds and arthropathy. The aim of this study was to assess the associ- ation between joint bleeds and arthropathy, meas- ured by the Pettersson score, in patients with severe haemophilia. Material and Methods The study population consisted of 117 patients with severe haemophilia A or B (factor VIII/IX