RUPTURES OF THE ACHILLES-TENDON - RELATIONSHIP TO INEQUALITY IN LENGTH OF LEGS AND TO PATTERNS IN THE FOOT AND ANKLE

We studied 101 patients who were operated on at Oulu University Hospit al for ruptured Achilles tendon from 1987 to 1992 (inclusive), and 87 healthy control patients from among Army conscripts. The mean inequali ty in length of legs (ILL) was 5 +/- 4 mm. Among the 48 patients with ILL greater than or equal to 5 mm, the side affected with ruptured ten don was longer in 48% of cases and shorter in 52%. An underpronating a lignment of the ankle and foot (based on beta(45) measurement of the a ngle less than or equal to 4 degrees) was found in 21% of patients and 5% of controls (P < 0.001). A combination of high longitudinal arch a nd underpronating alignment of the ankle was seen in 10% of patients a nd 1% of controls (P < 0.001). About 37% of the patients' feet and 29% of feet in controls were classified as having a high arch (P = 0.001) . ILL or hyperpronation of the ankle seem to not be predisposing facto rs for ruptures of the Achilles tendon. High longitudinal arches were somewhat overrepresented, being associated with less pronation of the ankle and less varus in the forefoot than was seen in controls.