Relapse After Tibialis Anterior Tendon Transfer in Idiopathic Clubfoot Treated by the Ponseti Method

SLR - March 2012 - Zachary G. Jagmin

Reference: Masrouha KZ, Morcuende JA. (2012) .Relapse After Tibialis Anterior Tendon Transfer in Idiopathic Clubfoot Treated by the Ponseti Method.  J Pediatr Orthop 32(1): 81-84.

Scientific Literature Review

Reviewed by:  Zachary G. Jagmin, DPM
Residency Program: Massachusetts General Hospital, Boston, MA

Podiatric Relevance: 
The Ponseti method of treatment for idiopathic clubfoot has historically led to successful outcomes as noted in short and long-term follow-ups. Relapses are a common and important management problem, believed to be related primarily to post-treatment bracing non-compliance. Tibialis anterior tendon transfer (TATT) to the lateral cuneiform is a well-accepted surgical treatment for relapses. However, recent data supports the notion that, even followed by conservative care, TATT does not guarantee a successful outcome. 

Methods:
The study was a retrospective chart review of all patients with idiopathic clubfoot at the authors’ institution, conducted from 1993 to 2009. A total of 848 patients were initially identified, all corrected by the same manipulation and casting method, and Achilles tenotomy when indicated. After 4 years of bracing per standard protocol, ninety-one (91) of these patients were treated with TATT for relapse. Twenty-five (25) patients were excluded from the study, leaving a total of sixty-six patients (102 clubfeet) identified. All patients underwent TATT by the same surgical team using the same operative and post-operative protocol. Medical records reviewed from initial visit to most recent follow-up documented: sex, laterality, age at initial presentation, initial number of casts, Achilles tenotomy vs no tenotomy, brace compliance, presence of neurological deficits, age at TATT, age at post-TATT relapse and clinical presentation, post-TATT relapse treatment, and age at last follow-up. Statistical analysis with t-test was performed.

Results:
Ten patients (15 feet total – 6 male & 4 female and 5 unilateral & 5 bilateral) of the 66 (15.2 percent) treated by TATT (mean age 16 months) developed a relapse. Eight of the 10 patients (80 percent) with post-TATT relapse were non-adherent to the bracing protocol. Mean age at pre-TATT relapse was 2.9 years, mean age at TATT was 3.1 years, and mean age at TATT of patients without later relapse was 4.5 years. The mean time to relapse following TATT was 1.9 years. All patients had a functioning TA tendon on physical examination at the time of post-TATT relapse. Treatment of post-TATT relapse included casting, AFO, physical therapy, or bracing. One patient was treated by medial cuboid and lateral cuneiform osteotomy, and one patient underwent peroneus longus to peroneus brevis tendon transfer. Two patients had neurological deficits diagnosed by anterior tibial muscle biopsy. 

Conclusions:
A 15.2 percent rate of post-TATT clubfoot relapse was reported in this study. These patients had similar rate of bracing protocol non-compliance and similar number of cast changes at initial treatment as compared to the remaining patients without post-TATT relapse. The authors concluded these patients may be at increased risk for relapse when TATT was performed at an earlier age or when undiagnosed neurological deficits existed.  If relapse occurs relatively shortly and/or frequently after TATT, close follow-up with cast and/or AFO treatment is recommended, and muscle biopsy should be performed to screen for neuromuscular deficits which may influence the success of future treatment.