['Calf muscle pump dysfunction is a recognized factor in chronic venous insufficiency (CVI). We investigated the hypothesis that limbs with CVI have a reduced ankle range of motion (ROM) that may be responsible for the poor calf pump function associated with venous ulceration.', 'Ankle ROM and calf pump function were assessed in 32 limbs of 26 adult men. Limbs were selected on the basis of clinical presentation: normal (n = 6 limbs), class 1 or 2 CVI with no history of ulceration (n = 9 limbs), class 3 CVI with healed ulceration (n = 9 limbs), and class 3 CVI with active ulceration (n = 8 limbs). ROM was determined by goniometry during maximal plantar flexion and dorsiflexion of the ankle. Calf pump function was determined by air plethysmographic measurement of ejection fraction (EF) and residual volume fraction (RVF).', 'Ankle ROM was significantly (p < 0.05) reduced in each CVI group compared with age-matched control subjects, because of decreases in both plantar flexion and dorsiflexion. Calf pump function was significantly impaired (decreased EF and increased RVF) in ulcerated limbs. ROM was significantly correlated to EF and RVF. Impairment of ROM and calf pump function was associated with deterioration in the clinical classification of venous disease.'] Is limited range of motion a significant factor in venous ulceration?