The Journal of Ultrasound in Medicine published research comparing lateral ankle ligaments between the unaffected and affected leg in children with spastic hemiplegia cerebral palsy. Eight children with a mean age of 5.2 years old underwent sonograms of the anterior talofibular ligament and calcaneofibular ligament and the anterior talofibular/calcaneofibular ligament thickness ratio was calculated. In addition, the modified Ashworth scale was used and passive ankle dorsiflexion was evaluated. The results indicated the following
anterior talofibular ligament thickness in the affected legs was significantly greater than that in the unaffected legs
calcaneofibular ligament thickness in the affected legs was significantly less than that in the unaffected legs
anterior talofibular/calcaneofibular ligament thickness ratio in the affected legs was significantly greater than that in unaffected legs (ratio was positively correlated with the modified Ashworth scale and age but negatively correlated with the passive ankle dorsiflexion angle in the affected legs).
The researchers concluded that there is an increased anterior talofibular ligament thickness and a decreased calcaneofibular ligament thickness in the affected legs compared with the unaffected legs. This discrepancy between the lateral ankle ligaments may play a role in the equinovarus deformity of the ankle together with spastic leg muscles in children with spastic hemiplegic cerebral palsy.
Reference: Kwon DR, Park GY. Differences in lateral ankle ligaments between affected and unaffected legs in children with spastic hemiplegic cerebral palsy. J Ultrasound Med. 2013 Feb;32(2):313-7.