A Comparison of Ankle Foot Orthoses with Foot Abduction Orthoses to Prevent Recurrence Following Correction of Idiopathic Clubfoot by the Ponseti Method

SLR - July 2011 - Evie Plummer

Reference: Janicki J.A., Wright J.G., Weir S, Narayanan, U.G. (May 2011) A Comparison of Ankle Foot Orthoses with Foot Abduction Orthoses to Prevent Recurrence Following Correction of Idiopathic Clubfoot by the Ponseti Method. Journal of Bone and Joint Surgery (British), 93(5), 700-704.

Scientific Literature Review

Reviewed by: Evie Plummer, DPM
Residency Program: North Colorado Medical Center

PODIATRIC RELEVANCE: 
Clubfoot deformity correction and maintenance may present a challenge for many podiatric physicians.  The Ponseti method of management of idiopathic clubfeet has gained popularity due to positive outcomes and high rates of success.  Following the initial correction by serial casting, there is a necessary maintenance period described by Ponseti, in which the use of a foot abduction orthoses is recommended for up to five years to minimize the risk of recurrence.  The foot abduction orthoses of Dennis Browne boots and bar (DBB) is often recommended throughout the maintenance period.  Many physicians, however, believe an ankle foot orthoses (AFO) to be as effective as DBB and more convenient for the child and family.

METHODS:
This retrospective study evaluated children with clubfeet presenting for treatment between 2001 and 2003 at the authors’ institution.  Children were included if they presented with a single or bilateral idiopathic clubfoot and had successfully undergone correction with Ponseti technique.   Weekly manipulation and casting was performed in all children until the correction was complete, and a percutaneous Achilles tenotomy was then performed to address the residual equinus.  A total of 45 children with 69 clubfeet were then included in this study in which the maintenance period consisted of bracing with either an AFO (17 children and 30 feet) or DBB (28 children and 39 feet).
 
RESULTS:
The mean follow-up was 60 months in the AFO group and 47 months in the DBB group, with the discrepancy due to the authors’ decision to change protocol to sole use of DBB in 2002 and thereafter.  Due to recurrence of the deformity, additional treatment was required in 25 feet (83%) of the AFO group and 12 feet (31%) in the DBB group.  Recurrence was noted to occur sooner in the AFO group (33.3 weeks) than in the DBB group (42.9 weeks).  At the three year follow up point, the probability of survival without recurrence for the AFO group was 0.17 compared to 0.72 for the DBB group.  Overall, the recurrence rate was 10.6 times higher in the AFO group.  The rate of additional necessary invasive procedures was 77% in children treated with AFO, compared to 18% in children treated with DBB.  The rate of more significant surgery (posterior or posteromedial release, osteotomy) was 70% in the AFO group and 5.1% in the DBB group.

CONCLUSIONS:
The authors concluded that the use the Ponseti method of clubfoot casting and DBB maintenance of correction remains a successful approach and allows usual avoidance of extensive surgery.  Following correction of clubfoot feet, the results demonstrate the superiority of DBB over AFO in providing maintenance of correction and preventing recurrence.  The abduction of the foot enforced by the DBB is necessary to stretch the medial soft tissues and aid in adequate maintenance of correction.  Recurrences do occur with the use of foot abduction orthoses, but they occur far less frequently than recurrence with the use of AFO.   If there is such recurrence following use of DBB, adequate management typically consists of repeat casting, with or without a second tenotomy, or limited posterior release.