The efficacy of the A-V impulse system in the treatment of posttraumatic swelling following ankle fracture

Objectives: To determine whether the use of the A-V Impulse "incast" system conveyed any clinical benefit in the treatment of post-traumatic swelling following ankle fracture. Design: A prospective randomised study comparing the effectiveness of the A-V Impulse "in-cast" system to that of elevation and plaster in the treatment of preoperative swelling. Setting: Clinical management in a large level 2 trauma center Patients: Sixty-four adult patients were recruited to the study who had sustained closed unilateral ankle fractures requiring internal fixation, but for whom immediate surgery was not possible. Intervention: All fractured ankles were treated with initial application of a plaster back-slab splint. Patients were randomized to either a control group of limb elevation or to a study group in whom an A-V Impulse bladder was fitted under the arch of the foot within the plaster back-slab and intermittent pneumatic pedal compression provided until surgery. Main Outcome Measurements: Daily Circumferential ankle girth measurements were performed. The time taken for swelling to resolve sufficiently to permit surgery, the development of skin complications, and the duration of hospitalisation were recorded. Results: Ten patients were withdrawn from the study. Twenty-seven patients in each group were followed up until discharge from outpatient care. Statistical analysis revealed a significant reduction in time taken for ankle swelling to settle prior to surgery (P = 0.01) in the study group, together with a reduction in wound and skin complications (P < 0.01) and final preoperative ankle swelling (P = 0.03). Conclusion: The A-V Impulse "in-cast" system demonstrated significant benefit in the management of adults with isolated ankle fractures who could not undergo immediate open reduction and internal fixation.