Traditionally, spinal fusion has been denied to patients with scoliosis secondary to Duchenne's muscular dystrophy (DMD) when their forced vital capacity (FVC) is less than 30-40% of predicted values (PFVC). The reasons for this decision are a theoretically increased risk of adverse events from a prolonged anaesthetic and extensive surgery. This paper presents a retrospective analysis of 30 patients with DMD scoliosis who underwent posterior spinal fusion at the Royal National Orthopaedic Hospital. Two subgroups of patients were compared: those with more than 30% PFVC (17 patients) and those with less than 30% PVFC (13 patients). One patient in each group required a temporary tracheotomy and there were nine complications in total. The post-operative stay for patients in each group was similar (24 days in the >30% group, 20 days in the <30% group) and the complication rate was comparable with other published series. We conclude that spinal fusion can be offered to patients with DMD even in the presence of a low FVC.