Ankle joint distraction is a promising alternative treatment for patients with severe haemophilic ankle arthropathy

Introduction: Haemophilic ankle arthropathy (HAA) causes major morbidity. When conservative treatment fails, major surgical interventions are indicated. An alternative treatment to maintain joint mobility and postpone these interventions is desired. Aim: To gather prospective data on clinical/structural changes after ankle joint distraction (AJD) in HAA. Methods: This study includes patients with severe HAA insufficiently responding to conservative treatment. AJD was performed during 8–10 weeks by use of an external frame. Questionnaires, physical examination and radiology were used to evaluate pain, function and structural changes before and 6, 12, 24 and 36 months after distraction. Mixed effect models were used for analysis. Results: This study includes eight cases (21–53 years). The fixed effects estimates of the visual analogue score (0–10) improved from 7.5 at baseline to 3.4 (p =.023) 3 years after distraction. The Haemophilia Activities List (HAL, 0–100) for basic/complex lower extremities functions improved from respectively 29.6 and 31.5 to 54.3 (p =.015) and 50.7 (p =.031). Joint mobility was maintained. Magnetic resonance imaging (MRI) showed thickened cartilage and reduced bone marrow oedema and subchondral cysts. Pin tract infections (n = 6) were effectively treated and no adverse bleeding events occurred. At 3-year follow-up, in none of the patients the originally indicated arthrodesis was performed. Conclusion: This first prospective study showed that AJD in HAA results in decreased pain, improved function and decreased arthropathy-related MRI findings in the majority of patients for prolonged time. Although the study population is small and follow-up is relatively short, AJD may be promising to postpone invalidating interventions and might be a breakthrough treatment.