ELECTROMYOGRAPHIC GAIT ANALYSIS FOR THE S TUDY OF THE SPASTIC FOOT INCEREBRAL-PALSY CHILDREN - A PRELIMINARY-REPORT

Purpose of the study This preliminary study describes the methodology and the results of gait analysis in cases of equinus and equino-varus deformity of the foot in cerebral palsy children. The ultimate goal wa s to establish an aid to decision in spastic foot surgical management. Material A prospective series of 12 walking children (16 feet) with c erebral palsy has been evaluated prior to-surgical correction of equin us or equino-varus deformity of the foot. The mean age was 8 years (ra nge 4 to 11 years of age). Results In four cases, the dynamic equinus was due to an extended or continuous contraction of the triceps surae. The varus deformity appeared to originate from two muscles: the tibia lis posterior in 9 cases and the tibialis anterior in 1 case. Both mus cles were responsible for the deformity in 2 cases. Two muscular activ ation patterns were observed in the tibialis posterior: inverted (2 fe et) or permanent (9 feet). From the main muscle which was responsible for deformity, we have determined the surgical technique which was mos t appropriate to restore the muscular balance. Discussion Our observat ions confirm Ferry's hypothesis, namely that selective and phasic cont rol during the walking cycle does not occur for patients suffering fro m cerebral palsy. Different surgical procedures were chosen according to the literature on this subject. In the treatment of equinus deformi ty, lengthening of the Achilles tendon is a satisfactory technique for hemiplegic patients. But we prefer gastrocnemius recession described by Vulpius in spastic diplegia in order to avoid overlengthening or ca lcanal gait. If it can be shown that posterior tibial muscle overactiv ity is the cause of equinovarus, we perform a posterior tibial tendon lengthening, as proposed by Ruda and Frost, or a split posterior tibia l tendon transfer as developed by Green. If the posterior tibial muscl e is active only during the swing phase, we accomplish a split posteri or tibial tendon transfer through the interosseus membrane as advocate d by Saji. If the anterior tibial muscle is continuously active, a spl it anterior tibial tendon transfer to the cuboid described by Hoffer i s performed. If the activity is continuous in both the tibial posterio r and the tibial anterior muscles, we add a posterior tibial myotendin ous lengthening to the split anterior tibia[ tendon transfer. Conclusi on Since 1992, we have developed in our situation a gait laboratory in order to bring objective data in the process of decision making for t endon transfer surgery. With 4 years experience, this objective suppor t now seems to us compulsory in decision of type of transfer. The goal of this preliminary study was to explain how we use the data and matc h these to our experience and literature.