Failure of Split Posterior Tibial Tendon Transfer in Cerebral Palsy Complex Foot Deformities: A Review of Failure Definitions and Risk Factors for Failure.

Purpose of review: This review examines variability in failure and recurrence rates following split posterior tibial tendon transfer (SPOTT) for spastic equinovarus deformity (SED) in children with cerebral palsy (CP). It evaluates patient-specific and surgical risk factors contributing to poor outcomes and assesses the inconsistent definitions of failure across the literature.

Recent findings: Across the seven included studies, failure was more common in patients under the age of 8, non-ambulatory individuals, and those with quadriplegic CP. Surgical contributors included poor tendon tensioning, residual spasticity, over- or under-correction, and untreated bony deformities. Although modified techniques demonstrated improved outcomes, the risk of recurrence was not completely eliminated. All studies consistently lacked standardized definitions of surgical failure and recurrence, limiting cross-study comparability. Postoperative management strategies-particularly structured bracing protocols and delaying surgery until after age 8-were associated with more favorable outcomes. SPOTT remains a viable surgical option for dynamic SED in children with CP, but long-term success is highly dependent on careful patient selection, surgical expertise, and consistent postoperative care. Inconsistent definitions of recurrence and failure remain a major barrier to improving clinical outcomes and conducting meaningful comparative research. To enhance clinical decision-making and guide future studies, a standardized grading system should be urgently developed and adopted in the field.