Ultrasonographic phases in gap healing following Ponseti-type Achilles tenotomy.

Background: The Ponseti technique is well established in the management of clubfoot deformity, and an Achilles tenotomy is frequently performed to facilitate dorsiflexion of the foot. This report describes the ultrasonographic phases of healing of the tendon gap created by the Achilles tenotomy and how the healing varies, if at all, with patient age.

Methods: A prospective ultrasonographic study of gap healing following a Ponseti-type tenotomy in twenty-seven tendons in twenty patients with idiopathic congenital clubfoot was performed. Serial ultrasound examinations (both static and dynamic) were performed at three, six, and twelve weeks after the tenotomy. The casts were removed routinely three weeks after the tenotomy. The end point of healing was defined as the observation of tendon homogeneity across the gap zone on ultrasound, with the divided tendon ends being indistinct.

Results: Three phases of healing were apparent on ultrasound assessment at three, six, and twelve weeks after the tenotomy. These sequential phases are similar to those previously described in the healing of tendons with no gap. The transition to normal structure was frequently demonstrated by ultrasonography only at twelve weeks (in thirteen of twenty-one tendons).

Conclusions: Although there is evidence of continuity of the Achilles tendon by three weeks after tenotomy, healing is not complete until at least twelve weeks. The time needed for the tendon to completely heal should be taken into consideration before a revision Achilles tenotomy is planned.