Triggered electromyography for placement of thoracic pedicle screws: is it reliable?

European Spine Journal

Jahangir Asghar⁴  David H. Clements²  Ashish Ranade³  Mark Tantorski⁵  Stephen Koch¹  Patrick J. Cahill⁴  Randal R. Betz⁴  Amer F. Samdani⁴ 

[1] Temple University School of Medicine, 3500 North Broad Street, Philadelphia, PA 19140 USA;Cooper Bone and Joint Institute, 3 Cooper Plaza, Suite 411, Camden, NJ 08103 USA;Department of Orthopaedic Surgery, Smt. Kashibai Navale Medical College & Hospital, Narhe, Pune, 411051 India;Shriners Hospitals for Children, 3551 N Broad Street, Philadelphia, PA 19140 USA;Philadelphia College of Osteopathic Medicine, 4170 City Avenue, Philadelphia, PA 19130 USA

关键词: Triggered electromyography;    Pedicle screws;    Thoracic;    Adolescent idiopathic scoliosis;    Posterior spinal fusion;   

DOI  :  10.1007/s00586-010-1653-x

学科分类：骨科学

来源: Springer

【 摘 要 】

Reliable electromyography (EMG) thresholds for detecting medial breaches in the thoracic spine are lacking, and there is a paucity of reports evaluating this modality in patients with adolescent idiopathic scoliosis (AIS). This retrospective analysis evaluates the ability of triggered EMG to detect medial breaches with thoracic pedicle screws in patients with AIS. We reviewed 50 patients (937 pedicle screws) undergoing posterior spinal fusion (PSF) with intraoperative EMG testing. Postoperative CT scans were used for breach identification, and EMG values were analyzed. There were 47 medial breaches noted with a mean threshold stimulus of 10.2 mA (milliamperes). Only 8/47 breaches stimulated at 2–6 mA. Thirteen of the forty-seven screws tested at an EMG value ≤6 mA and/or a decrease of ≥65% compared with intraosseously placed screws. The sensitivity and positive predictive value for EMG was 0.28 and 0.21. A subanalysis of T10–T12 screws identified six of seven medial breaches. Using guidelines from the current literature, EMG does not appear to be reliable in detecting medial breaches from T2 to T9 but may have some utility from T10 to T12.

【 授权许可】

Unknown