Postoperative Calcaneocuboid Joint Subluxation and Midtarsal Joint Changes in Pediatric Idiopathic Flexible Flatfoot Treated With Calcaneal Lengthening Osteotomy: A Midterm Follow-up Study.

BACKGROUND

Calcaneal lengthening osteotomy (CLO) is one of the main surgical options for treatment of pediatric idiopathic flexible flatfoot (FFF). Reportedly, calcaneocuboid (CC) joint subluxation occurs after CLO; however, its effect on the midfoot remains unclear. This study aimed to investigate the radiologic midterm results after CLO treatment in pediatric idiopathic FFF.

METHODS

We evaluated 23 pediatric patients with idiopathic FFF aged ≥8 years, who underwent CLO from 1999 to 2017 owing to moderate to severe flatfoot deformity (assessed by visual inspection). Patients aged between 8 and 14 years were included (mean follow-up: 6.3 years; range, 3.1-11.4 years). Anteroposterior and lateral weightbearing foot radiographs were assessed for radiologic parameters preoperatively and at the 3-month, 1-year, and final follow-ups postoperatively.

RESULTS

All patients had immediate postoperative radiologic correction of the flatfoot deformity, and these improvements were maintained until the final follow-up. The mean allograft length inserted was 9 (range, 8-10) mm. There was increased CC joint subluxation after CLO, but it improved continuously until the final follow-up. A CC joint spur was newly noted in 1 case. There were 24 cases (24/39, 61.5%) of talonavicular (TN) joint spurs at the final follow-up, but 19 of these were already present on the preoperative radiographs (19/24, 79.2%). Further, the new-onset TN joint spurs were not associated with preoperative clinicoradiologic factors.

CONCLUSION

In pediatric patients with idiopathic FFF receiving CLO treatment, preoperative radiologic angles improved. CC joint subluxation increased after surgery; however, it gradually reduced without evidence of CC joint arthritic changes over the time period studied in this cohort.