Forty patients with subcutaneous rupture of the Achilles tendon were enrolled in a prospective study and randomised to two groups: group A treated with open surgery with Kessler-type suture, and group B treated by percutaneous tenorraphy (Tenolig®) under ultrasound control. The follow-up included an objective and a subjective (SF-12) clinical evaluation at 4, 12 and 24 months, ultrasonography at the same time points, and isokinetic muscle performance tests at 12 months. There were no significant differences between the two groups at clinical and ultrasound evaluation except for a greater ankle circumference in group B (p< 0.01) at 12 months; peak torque and total work isokinetic tests did not differ significantly in the two groups nor between involved and uninvolved side. At 24 months data show similar clinical and ultrasonographic results with both techniques, leading us to prefer percutaneus tenorraphy under ultrasound control owing to the attendant advantages of local anaesthesia in day surgery, decreased risk of skin complications, reduced surgical time, faster functional recovery, and greater patient compliance.