Kinematic and Kinetic Changes of the Ankle After the Correction of Spastic Equinus Deformity: Z-plastic Lengthening versus Strayer Method

Chung, Chin Youb; Ahn, Chang Hoe; Choi, In Ho; Cho, Tae Joon; Shin, Yong Woon; Yoo, Won Joon

Abstract

PURPOSE: The purpose of this study was to evaluate the post-operative changes and to determine the factors affecting results obtained after surgical correction of spastic equinus deformity.
MATERIALS AND METHODS
Among cerebral palsy patients who had received Tendo Achilles Lengthening (TAL) or the Strayer procedure, eighty nine patients (114 cases: TAL, 78 cases and Strayer, 36 cases) were included in this study. We evaluated clinical assessment data, kinematic data, and kinetic data pre- and post-operatively, according to the geographic type of cerebral palsy, age at operation, and sex.
RESULTS
Clinically, equinus deformities were corrected with an increased passive range of motion of the ankle in both groups. Accord-ing to the kinematic results, both groups showed a normal ankle motion pattern with an increased dynamic range of motion. Kinetic results revealed that peak plantarflexor moment and power generation (A2) increased in both groups and that this increase was statisti-cal significant in TAL group.
CONCLUSION
Both the TAL and Strayer procedures corrected the spasticity and equinus deformity, and resulted in an increased dynam-ic range of motion of the ankle joint without compromising the triceps power. However, care must be taken not to decrease power gen-eration when TAL is performed in diplegic cases older than 13 years of age.