title: Acute deformity correction of lower extremities under SSEP-monitoring control.
abstract: Intraoperative somatosensory evoked potential (SSEP) monitoring was performed in eight children who had undergone an acute deformity correction in the lower extremities using external fixation. Five patients showed stable evoked potentials during surgery and had no neurologic complications postoperatively. Three patients experienced evoked potential abnormalities. In one patient, 60 degrees external rotation of the foot produced significant SSEP changes. The reduction of rotation to 40 degrees resulted in tibial but not peroneal SSEP recovery. Peroneal nerve deficit was noted postoperatively. The second patient showed substantial SSEP attenuation after 45 degrees correction of distal tibial valgus. However, spontaneous recovery of the response occurred, which allowed maintenance of the achieved correction. In a third patient, significant SSEP changes occurred after 90 degrees external rotation and 10 mm medial translation of the distal femur. Total release of translation allowed 75 degrees external rotation without SSEP abnormalities. Neither of the latter two patients had peripheral nerve deficits postoperatively. Intraoperative SSEP monitoring thus helps to define a neurologically safe limit of acute deformity correction.
authors.affiliation: Seay Center for Musculoskeletal Reseach, Texas Scottish Rite Hospital for Children, Dallas, Texas 75219, USA. marina.makarov@tsrh.org
authors.forename: Marina R
authors.initials: MR
authors.lastname: Makarov
authors.forename: Mikhail L
authors.initials: ML
authors.lastname: Samchukov
authors.forename: John G
authors.initials: JG
authors.lastname: Birch
authors.forename: Charles E
authors.initials: CE
authors.lastname: Johnston
authors.forename: Mauricio R
authors.initials: MR
authors.lastname: Delgado
authors.forename: Patricia L
authors.initials: PL
authors.lastname: Rampy
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Van Allen
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D006801:Humans; D035002:Lower Extremity / Q000601:surgery*; D008297:Male; D016343:Monitoring, Intraoperative; D016896:Treatment Outcome