Purpose of Study. Lengthening of the gastrocsoleus for equinus deformity is commonly performed in orthopaedic surgery. The aim of this study was to describe the precise details of each surgical procedure and assess each biomechanically in cadaver models. Description of Methods. The surgical anatomy of the gastrocsoleus was investigated and standardized approaches were developed for the procedures described by Baumann, Strayer, Vulpius, Baker, Hoke and White. The biomechanical characteristics of these six procedures were then compared, in three randomized trials, in formalin preserved, human cadaver legs. The lengthening procedures were performed and a measured dorsiflexion force was applied across the metatarsal heads using a torque dynamometer. Lengthening of the gastrocsoleus was measured directly, by measuring the gap between the ends of the fascia or tendon. Summary of Results. The gastrocsoleus muscle-tendon-unit was divided into three zones. In Zone 1, it was possible to lengthen the gastrocnemius alone or to lengthen the gastrocnemius and soleus by different amounts. These procedures (Baumann, Strayer) were very stable but limited in the amount of lengthening achieved. Zone 2 lengthenings (Vulpius, Baker) of the conjoined gastrocnemius aponeurosis and soleus fascia were not selective but were stable and resulted in significantly greater lengthening than Zone 1 (p < 0.001) 4. Conclusion. Surgery for equinus deformity correction by lengthening of the gastrocsoleus varies in terms of selectivity, stability and range of correction with differing anatomical and biomechanical characteristics. Clinical trials are needed to determine whether these differences are of clinical importance. It may be appropriate for surgeons to select a procedure from a zone, best suited to the clinical needs of a specific patient. NO DISCLOSURES

Purpose of Study. In children with spastic diplegia, surgery for equinus has a high incidence of both over and under correction. We wished to determine if conservative (mainly Zone 1) surgery for equinus gait, in the context of multilevel surgery, could result in the avoidance of calcaneus and crouch gait as well as an acceptable rate of recurrent equinus, at medium term follow-up. Description of Methods. This was a retrospective, consecutive cohort study of children with spastic diplegia, between 1996 and 2006. All children had distal gastrocnemius recession or differential gastrocsoleus lengthening, on one or both sides, as part of Single Event Multilevel Surgery. The primary outcome measures were the Gait Variable Scores (GVS) and Gait Profile Score (GPS) at two time points after surgery. Summary of Results. Forty children with spastic diplegia, GMFCS Level II and III were eligible for inclusion in this study. There were 25 boys and 15 girls, mean age 10 years at surgery. The mean age at final follow-up was 17 years and the mean postoperative follow-up period was seven years. The mean ankle GVS improved from 18.5° before surgery to 8.7° at short term follow-up (P<0.005) and 7.8° at medium term follow-up. Equinus gait was successfully corrected in the majority of children with a low rate of over-correction (2.5%) but a high rate of recurrent equinus (35.0%), as determined by sagittal ankle kinematics. Conclusion. Surgery for equinus gait, in children with spastic diplegia, was successful in the majority of children, at a mean follow-up of seven years, when combined with multilevel surgery, orthoses and rehabilitation. No patients developed crouch gait and the rate of revision surgery for recurrent equinus was 12.5%. NO DISCLOSURES