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 - March 2015 - Emily A. Quinn

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-A(1): 47-55.

Scientific Literature Review

Reviewed By: Emily A. Quinn, DPM
Residency Program: Grant Medical Center, Columbus Ohio

Podiatric Relevance: The purpose of this study is to evaluate the effectiveness of the anterior tibial tendon transfer in idiopathic relapsing clubfoot previous treated by the Ponseti casting method. Idiopathic clubfoot is a congenital problem most commonly treated with the Ponseti method of serial manipulations and casts followed by bracing. Relapsing supination deformity and heel varus is reported in the literature as high as 56 percent of cases of idiopathic clubfoot treated by casting and manipulation. Given the young age that the podiatric patient is treated with tendon transfers for relapsing clubfoot, long-term results in the adult population are often questioned and under reported. This article evaluates the long term outcomes of the tibialis anterior tendon transfer on foot function in the adult patient.

Methods: The authors retrospectively reviewed prospectively collected data from all patients treated for idiopathic clubfoot utilizing the Ponseti method at the University of Iowa from 1950 to 1967 with all treatments performed by Dr. Ignacio Ponseti. Tibialis anterior tendon transfer was performed based on severity of relapse, dynamic supination deformity, varus heel, and difficulties with bracing compliance. Exclusion criteria was limited to congenital anomalies, neuromuscular disease, previous surgery and prior treatment for clubfoot other than up to three plaster casts. 126 patients met the inclusion criteria. Of the 126 patients, 89 patients were able to be located. Of these 89 patients, 35 were present for a follow up exam with an average time of final follow up of 43 years. Of the 35 patients, 14 (40 percent) had a tibialis anterior tendon transfer, while 21 (60 percent) did not under go tendon transfer and therefore were the reference group. Foot function questionnaires, which are the AAOS, the Laaveg Ponseti, and the foot function index, were obtained. Physical exam parameters including: height, weight, foot length, foot width, calf circumference, tenderness to palpation, motor strength; and number of single legged toe ups they could perform were obtained, along with ankle plantar flexion-dorsiflexion, heel varus-valgus, and forefoot inversion-eversion. Radiographic angular relationships on standing anterioposterior, lateral and hindfoot films were reviewed. Surface electromyography patterns from the tibialis anterior, lateral gastrocnemius and the peroneus longus muscles during ambulation were evaluated.

Results: No patient in the tibialis anterior tendon group had a relapse or required additional procedures for the clubfoot. Three patients in this group did have unrelated procedures performed. Five patients (7 feet) in the reference group did have a relapse of the deformity requiring repeat casting. There was no significant difference between the two groups in regard to sex, race, age, height, weight, foot length, foot width, and calf circumference. There was no significant difference in all three foot function questionnaires. The only physical exam finding to elicit a significant difference between the two groups was the tibialis anterior tendon transfer group which was able to perform and complete a significantly higher number of single legged toe raises as compared to the reference group (p<0.01). All other physical exam findings were not significant. Radiographic angular relationships were noted to be significantly smaller in the AP talocalcaneal angle for the tendon transfer groups as compared to the reference group (p=0.048). Also of note, the tendon transfer group had a significantly higher number of patients with moderate to severe talar flattening (p=0.03). In regard to radiographic arthritic changes, the navicular-cuneiform joint in the tendon transfer group had significantly higher amount of moderate to severe osteophytes (p=0.024).  Surface EMG’s demonstrated no difference between the two groups.

Conclusion: This study demonstrates that the tibialis anterior tendon transfer is effective as no patient who underwent the tendon transfer had a relapse or required further surgical intervention for the clubfoot as compared to 7 feet in the reference group. Although radiographic findings including degenerative changes and a smaller AP talocalcaneal angle were significantly worse in the tendon transfer group, there was no difference in foot function questionnaires and pain scales. This study demonstrates that the tibialis anterior tendon transfer is an effective and powerful procedure for treatment of relapsed idiopathic clubfoot at long term follow up of 43 years and does not affect the overall long term function of the foot.