Split Posterior Tibialis Tendon Transfer and the Recurrence Rate of Equinovarus Deformity in Patients With Cerebral Palsy: A Systematic Review and Meta-Analysis.

Background: Cerebral palsy (CP) is the most common motor disability of childhood, predominantly characterized by spasticity. A frequent complication of spastic CP is equinovarus deformity, resulting in pain, instability, and altered gait, significantly affecting ambulation. Surgical intervention, particularly the split posterior tibialis tendon transfer (SPOTT), is often required to correct deformity when conservative management fails. However, the variability in outcomes and recurrence rates across different patient subtypes and surgical techniques remains unclear. This systematic review aimed to evaluate the recurrence rate of equinovarus deformity in children with CP after SPOTT, with a focus on factors such as age, CP subtype, and functional status.

Methods: A systematic search of MEDLINE, Embase, and Emcare databases was performed to identify observational studies reporting recurrence rates after SPOTT in pediatric patients with CP (aged ≤18 years). Studies with short follow-up periods (<12 months), non-English articles, conference abstracts, and those involving concomitant bony procedures were excluded. Statistical analyses used random-effects meta-analysis models to calculate pooled recurrence rates. All statistical analyses were performed, and forest plots were generated using R (version 4.3.2).

Results: Nine studies (325 patients, 366 feet) met the inclusion criteria. The mean age at surgery was 10.35 years, with a mean follow-up duration of 76.18 months. The overall pooled recurrence rate of equinovarus deformity after SPOTT was 11.4% (95% confidence interval 5.0-17.8), with substantial heterogeneity (I2 = 71.9%). Subgroup analysis revealed higher failure rates among nonambulatory patients with quadriplegic CP (47.6%) compared with ambulatory hemiplegic patients (6.6%). The optimal age window for SPOTT seemed to be between 6 and 10 years as younger patients demonstrated increased risks of valgus deformity, whereas older patients had higher recurrence rates. Variations in surgical techniques, including interosseous membrane versus circumtibial routing, were identified as potential sources of heterogeneity.

Conclusion: SPOTT seems to be an effective intervention for correcting equinovarus deformity in ambulatory patients with CP, particularly those with hemiplegia or diplegia. However, nonambulatory and quadriplegic patients are at higher risk of recurrence, warranting careful patient selection. These conclusions should be interpreted with caution because of substantial study heterogeneity and the variability in surgical techniques reported. Further high-quality studies with standardized reporting and direct comparisons between surgical techniques are necessary to optimize outcomes and inform clinical practice.

Level of evidence: Therapeutic Level IV, systematic review. See Instructions for Authors for a complete description of levels of evidence.