# Dynamic radiographic angle changes in planovalgus foot correction among children with cerebral palsy

## TL;DR

This study examines how radiographic angles in children with cerebral palsy change before and after foot surgery, showing initial improvement with some regression over time.

## Contribution

The study provides a detailed analysis of dynamic radiographic angle changes following calcaneal lengthening surgery in children with cerebral palsy.

## Key findings

- Immediate postoperative improvement in radiographic angles confirms effective deformity correction.
- Partial regression of some angles over two years suggests dynamic deformity behavior influenced by growth and neuromuscular factors.

## Abstract

Planovalgus foot is the most frequent foot deformity in children with cerebral palsy (CP), often impairing gait and functional mobility. Radiographic angular measurements are essential tools for assessing deformity severity and monitoring postoperative outcomes, yet their dynamic behavior after correction remains poorly characterized.

To analyze pre- and postoperative variations of radiographic angles in spastic planovalgus feet surgically treated using Mosca’s calcaneal lengthening technique within a retrospective cohort, and to provide an educational reference for orthopedic residents regarding angular behavior and measurement interpretation.

A retrospective, longitudinal, descriptive study was performed on 132 (128 patients; 4 bilateral cases) feet of children with CP (GMFCS I–V) undergoing calcaneal lengthening, with or without adjunctive procedures (reefing or arthrodesis). Standardized weight-bearing anteroposterior and lateral radiographs were analyzed at five time points (preoperative, immediate postoperative, 6 months, 1 year, and 2 years). The evaluated angles included: AP talocalcaneal (Kite’s), AP talo–first metatarsal, talonavicular coverage, calcaneus–fifth metatarsal (C5M), Costa–Bartani, Meary’s, lateral talocalcaneal, and calcaneal inclination. Descriptive statistics were applied to assess temporal evolution.

All radiographic parameters showed immediate postoperative improvement, confirming effective deformity correction. The AP talocalcaneal angle decreased from 31.6° preoperatively to 24.0° postoperatively, while the calcaneal pitch increased from 7.1° to 19.1°. Mild regression was observed in several angles particularly C5M and Meary’s at two years, likely reflecting growth-related and neuromuscular factors.

Calcaneal lengthening provides measurable and durable radiographic correction in CP-related planovalgus foot, although partial regression of some parameters over time highlights the dynamic nature of the deformity. Radiographic angles remain reliable for postoperative monitoring and educational training, supporting their use as a standardized multi-angle assessment tool in the medium-term management of these patients.

The online version contains supplementary material available at 10.1007/s00402-026-06206-6.