Local and distant effects of isolated calf muscle lengthening in children with cerebral palsy and equinus gait

Abstract

The purpose was to assess the local and distant effects of isolated calf muscle lengthening in ambulant children with cerebral palsy. The study included fifteen ambulant children with cerebral palsy (nine with diplegia and six with hemiplegia), average age 8.8 years, Gross Motor Function Classification System (GMFCS) level I and II. None of the children had previously undergone orthopaedic surgery, apart from one child who had tendo-achilles lengthening (TAL) nine years earlier. All the children underwent pre and post-operative clinical examination and three-dimensional gait analysis (gait analysis). Twenty calf muscle lengthenings were performed, ten TAL and ten gastrocnemius recessions (GR). Post-operative ankle kinematics showed significant improvements in all parameters. Ankle power during push-off increased, but only significantly after TAL. Only one limb (5%) was over-corrected. Four limbs (20%) were under-corrected and one of these limbs remained in mild equinus position in stance. There was one recurrent equinus (5%) during the follow-up period of three years (range: 13-55 months). Distant effects on joints and segments were more marked in diplegia than in hemiplegia. Ten of 17 kinematic parameters distant from the ankle joint improved significant post-operatively when the preoperative values were 1SD below or above the mean of the normal material. There was no significant deterioration in any of the measured parameters. The improvement in ankle kinematics and kinetics supported the experience of other studies. The distant effects, which have previously not been evaluated in three planes, showed improvement in several kinematic parameters indicating that additional surgery in selected patients could be abandoned or delayed.