Can PEEK cage replace bone graft in calcaneal lengthening osteotomy in treatment of pediatric pes planovalgus?

Flatfoot deformity can cause significant functional impairment, often necessitating surgical correction. Calcaneal lengthening osteotomy is a well-established procedure; however, traditional bone grafts have limitations such as donor site morbidity and nonunion risk. Polyether ether ketone (PEEK) cages offer a novel alternative, potentially enhancing surgical outcomes through improved biomechanical properties and bone incorporation.

To evaluate the efficacy of PEEK cages in lateral calcaneal lengthening osteotomy in adolescent patients.

This prospective study included 41 adolescent patients with symptomatic flatfoot undergoing lateral calcaneal lengthening osteotomy using PEEK cages. Radiographic parameters, including calcaneal inclination angle (CIA) and talo-first metatarsal angles (TFA), were assessed preoperatively and postoperatively. Functional incorporation was evaluated using Worth et al.'s classification. Patients were followed for at least one year.

Postoperative radiographic assessments showed significant improvement. The median CIA increased from 3° (0°-7°) to 17° (12°-20°) (P < 0.001). TFA lateral decreased from 20° (11°-26°) to 2° (0°-8°) (P < 0.001), and TFA anteroposterior reduced from 22° (14°-28°) to 3° (0°-9°) (P < 0.001). At one-year follow-up, 92.7% of 41 patients demonstrated satisfactory incorporation (Grades III-IV). Complications included cage subsidence (7.3%) and pseudoarthrosis (2.4%).

PEEK cages in calcaneal lengthening osteotomy demonstrated excellent radiographic and clinical outcomes, with high incorporation rates and minimal complications.