We observed the healing process of ruptured Achilles tendons in a series of examinations using magnetic resonance imaging. The Achilles tendons are co-joined in two shapes in the incipient stage. One is the dumbbell shape and the other is the spindle shape. The tendon tended to co-join in the dumbbell shape in the conservatively treated group, while it tended to co-join in the spindle shape in the surgically treated group. The ruptured part tended to co-join in the spindle shape when it was narrow (less than 4mm), and in the dumbbell shape when wide (more than 5mm). The diameters from the anterior to posterior sides enlarged in the process for both shapes, and no significant difference was seen between the two shapes. No significant difference was also seen between the two for the healing time of the ruptured part. Regardless of the above finding, it is impossible to deny that surgical treatment promotes earlier healing of the ruptured part than conservative treatment, according to the relationship between the size of the ruptured part and co-joining shape.
