The split transfer of tibialis anterior tendon to peroneus tertius tendon for equinovarus foot in children with cerebral palsy

Split Transfer of the Tibialis Anterior Tendon Combined With Calcaneocuboid Fusion vs Split Transfer of the Tibialis Anterior Tendon Alone to Treat Equinovarus Foot Deformity in Children With Cerebral Palsy

BACKGROUND

The study aimed to compare the outcomes of combined calcaneocuboid arthrodesis and split anterior tibialis tendon transfer (SPLATT) procedure to isolated SPLATT surgery for the treatment of the spastic equinovarus deformity in children with cerebral palsy (CCP).

METHODS

Forty-one ambulatory CCP with 56 equinovarus feet, with positive flexor withdrawal reflex test results, were studied. The average age was 9.1 ± 3.2 years (range 3-22). Patients were assigned into 2 groups based on the surgical procedures. Patients in group 1 underwent isolated SPLATT surgery, whereas patients in group 2 underwent the SPLATT procedure combined with calcaneocuboid arthrodesis. All feet were followed for at least 12 months after surgery. Patients were evaluated preoperatively and at the most recent follow-up visit. The hindfoot positions were assessed using Chang's criteria, the functional outcomes were assessed using Kling's criteria, and the ambulatory levels were assessed using the Gross Motor Function Classification System (GMFCS).

RESULTS

Patients were followed for an average of 30.4 ± 14 (range 14-84) months. We found no difference between the groups in Chang's scoring (P = .550), better clinical outcomes (P = .034) according to the Kling criteria in SPLATT with calcaneocuboid fusion group, and postoperative GMFCS levels better in the SPLATT with calcaneocuboid fusion group (P = .025).

CONCLUSION

In this retrospective comparative study to treat children with spastic equinovarus feet, patients who had the SPLATT procedure combined with calcaneocuboid arthrodesis generally resulted in better functional outcomes compared to isolated SPLATT surgery in spastic equinovarus foot.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

The efficacy of split tibial tendon transfers on functional gait outcomes for children and youth with cerebral palsy and spastic equinovarus foot deformities

To systematically review the efficacy of split tendon transfer surgery on gait-related outcomes for children and adolescents with cerebral palsy (CP) and spastic equinovarus foot deformity. Five databases (CENTRAL, CINAHL, PubMed, Embase, Web of Science) were systematically screened for studies investigating split tibialis anterior or split tibialis posterior tendon transfer for spastic equinovarus foot deformity, with gait-related outcomes (published pre-September 2022). Study quality and evidence were assessed using the Methodological Index for Non-Randomized Studies, the Risk of Bias In Non-Randomized Studies of Interventions, and the Grading of Recommendations Assessment, Development and Evaluation. Overall, 17 studies (566 feet) were included: 13 studies used clinical grading criteria to report a postoperative 'success' of 87% (75% to 100%), 14 reported on orthotic use with 88% reduced postoperative use, and one study reported on ankle kinematics improvements. Ten studies reported post-surgical complications at a rate of 11/390 feet (2.8%), but 84 feet (14.8%) had recurrent varus (68 feet, 12%) or occurrence of valgus (16 feet, 2.8%). Only one study included a patient-reported outcome measure (pain). Split tendon transfers are an effective treatment for children and youth with CP and spastic equinovarus foot deformities. Clinical data presented can be used for future study designs; a more standardized functional and patient-focused approach to evaluating outcomes of surgical intervention of gait may be warranted.

Absence of Peroneus Tertius in Split Anterior Tibialis Tendon Transfer Surgery

Split anterior tibialis tendon transfer is a common orthopedic surgical procedure for varus foot deformities. In the absence of the peroneus tertius, the peroneus brevis may be used in the transfer. Little is known about the prevalence of each transfer type. The goal of this study is to understand trends in tendon transfer for patients who undergo split anterior tibialis tendon transfer. Records of all patients who underwent tibialis anterior tendon split transfer at our institution between January 2004 and September 2020 were reviewed. After, 337 subjects who underwent tibialis anterior tendon split transfer were included. The peroneus tertius was absent in 33.2% (112/337) of subjects. Logistic regressions showed the odds of having a missing peroneus tertius were 66.9% lower for subjects with cerebral palsy and related etiologies (odds ratio [OR]: 0.331, 95% confidence interval [CI]: 0.21, 0.53), 47% lower for white subjects (OR: 0.53, 95% CI: 0.31, 0.91), and 59.1% lower for non-Hispanic subjects (OR: 0.409, 95% CI: 0.25, 0.66). The odds of a missing peroneus tertius tendon were 2.72 times higher for subjects who identified in the other racial category (95% CI: 1.65, 4.49), and 2.41 times greater for subjects who identified as Hispanic (95% CI: 1.51, 3.84). Patients who underwent the procedure who identified as Hispanic or members of other (non-White, -Black, -Asian) racial groups had an increased likelihood of having a missing peroneus tertius tendon. Patients who identified as white, having cerebral palsy or related etiologies, or non-Hispanic had a decreased risk of having a missing peroneus tertius tendon.