Long-Term Results of Tibialis Anterior Tendon Transfer for Relapsed Idiopathic Clubfoot Treated with the Ponseti Method: A Follow-up of Thirty-seven to Fifty-five Years

SLR - April 2016 - Michelle Dole

Reference: Holt JB, Oji DE, Yack HJ, Morcuende JA. Long-Term Results of Tibialis Anterior Tendon Transfer for Relapsed Idiopathic Clubfoot Treated with the Ponseti Method: A Follow-up of Thirty-seven to Fifty-five Years. J Bone Joint Surg Am. 2015 Jan 7;97(1):47-55.

Reviewed By: Michelle Dole, DPM
Residency Program: Hennepin County Medical Center, Minneapolis, MN

Podiatric Relevance: Previously published studies have documented that congenital talipes equinovarus (clubfoot) responds well to treatment with the Ponseti method of serial casting followed by abduction bracing. However, in cases of relapse, multiple surgical approaches have been described, including tibialis anterior tendon transfer to the lateral foot. While this treatment is known to be effective short term, this study looks at the long-term outcomes of tibialis tendon transfer in cases of relapsed clubfoot. Knowing the long-term effects can help surgeons decide the best procedure for their patients when the need arises for surgical treatment of relapsed clubfoot.

Methods: The authors conducted a retrospective review of data collected from all patients treated for idiopathic clubfoot with the Ponseti method at the University of Iowa from 1950 to 1967. All patients were treated by Dr. Ignacio Ponseti. Anterior tibialis tendon transfer was performed based on several factors: the severity of relapse, the amount of supination deformity and varus heel malalignment, and difficulty with bracing due to patient age. The medical records of 126 total patients were reviewed. Patients with congenital anomalies, neuromuscular disease, previous surgery, or prior treatment of clubfoot with more than three plaster casts were excluded. Thirty-five total patients responded for follow-up questionnaires and clinical examination. Of these patients, fourteen were treated with tibialis anterior tendon transfer and twenty-one were treated with casting and bracing alone. The tibialis anterior tendon was transferred to the third cuneiform in the majority of feet, but transfers were also performed to the second cuneiform and the cuboid. The operative limb was immobilized after surgery in a toe-to-groin plaster cast for six weeks. No additional bracing was used following this time period. Tendon transfers were performed on patients who were 5-years-old on average. Patients were evaluated at follow up using several foot function questionnaires, physical examination, radiographic examination, pedobarographic analysis, and surface electromyography patterns. The average age at follow up was forty-seven years, with an average time to follow up of forty-three years.

Results: At follow-examination, no patients treated with anterior tibialis tendon transfer had an additional relapse or required additional clubfoot treatment. There were no significant differences found between groups when evaluating the number of casts performed for initial treatment or the percentage of feet treated with Achilles tenotomy. There were no significant differences between groups with regard to sex, race, age, height, weight, foot length, foot width, or calf circumference. No significant differences were found on the AAOS Foot and Ankle Outcomes Questionnaire or the Foot Function Index, although patient satisfaction tended to be higher as reported on the Laaveg-Ponseti functional rating score. On physical examination, pain and range of motion were similar between groups. The most common symptom was pain at the previous Achilles tenotomy site. On radiographic exam, the tendon transfer group had a significantly smaller anteroposterior talocalcaneal angle when compared to the reference group. More severe talar flattening and more significant osteophyte formation at the navicular-cuneiform joint were observed in the transfer group. There were no differences in pedobarographic data or surface electromyography analysis between groups.

Conclusions: This study demonstrates that tibialis anterior tendon transfer to the lateral foot is a successful treatment for relapsed clubfoot deformity and remains effective long term. No patients underwent a repeat procedure or casting for clubfoot treatment after their initial tendon transfer. There were few differences between the groups overall, and similar functional and clinical outcomes were observed. While this study is small and only looks at the outcomes of one surgical procedure, it does demonstrate a long time to follow up, which is an important factor to consider when planning for operative intervention. Ideally most patients would avoid such a procedure with casting and bracing compliance; however in cases where surgical intervention is necessary, this procedure is an option with demonstrated functional and clinical success.