Great toe metatarsophalangeal arthrodesis for hallux valgus deformity in ambulatory adolescents with spastic cerebral palsy

Abstract

Background: Hallux valgus deformity is a common sequel of spastic cerebral palsy.

Methods: Twenty ambulatory patients (24 feet) suffering hallux valgus deformity, with painful forefoot and restricted footwear, secondary to spastic cerebral palsy acquired perinatally, were treated with great toe metatarsophalangeal (MTP) arthrodesis using percutaneous K-wires for fixation. The mean age at the time of surgery was 16.2 years (range 14-18 years). They were retrospectively evaluated for the results after arthrodesis at a mean interval of 3 years and 4 months (range 3-4 years) by physical examination and radiographs.

Results: All patients had a stable painless aligned great toe, with <10 degrees valgus, <20 degrees dorsiflexion and neutral rotation after arthrodesis, evidenced by improvement in pain, cosmesis, functional activity, footwear, callosities and hygiene, as well as by significant improvement in the measures of the MTP and the intermetatarsal angles (IMA) by postoperative radiographs. Neither non-union (pseudoarthrosis) nor recurrence of the deformity developed. Complications included superficial wound slough in a single case. Using the modified American Orthopaedic Foot Ankle Society (AOFAS) Hallux Metatarsophalangeal-Interphalangeal Scale, 18 feet (75%) were classified as excellent and six feet (25%) as good. Neither fair nor poor cases were recorded.

Conclusion: Hallux valgus deformity in adolescents with spastic cerebral palsy is best treated by great toe MTP arthrodesis to improve segmental foot malalignment and dynamic foot deviation.

Fig. 1

Preoperative: a anteroposterior metatarsophalangeal (MTP) or hallux valgus angle (HVA); b anteroposterior intermetatarsal angle (IMA); c lateral MTP angle (LAT-MTPA) measurements of the left foot; d previous metatarsal neck osteotomy of the right foot in the anteroposterior view; e lateral view, i.e. a bilateral case

Fig. 2

Postoperative: a anteroposterior view of the left foot on the second day postoperatively; b lateral view; c anteroposterior view 12 weeks postoperatively; d lateral view with complete fusion and reduction of the angle measurements; e anteroposterior view 12 weeks postoperatively after revision of the right side by fusion; f lateral view with reduced angle measurements; g preoperative picture of recurrent right (notice the operative scar of the previous metatarsal neck osteotomy) but new left hallux valgus; h postoperative correction of the left great toe; i postoperative correction of the right great toe