title: The lumbosacral electromyographic screen: revisiting a classic paper.
abstract: OBJECTIVE
  Knutsson (Acta Orthopaed Scand (1961) 1) published a classic thesis comparing lower limb electromyography (EMG) results with intra-operative findings for 206 patients with sciatica. This unique and detailed work presented a rare opportunity to again use this data and determine the optimal number of muscles in a screening examination; a different study aim to that of the original investigator.
  
  
  METHODS
  Data from Knutsson (1961) were used to determine the identification rates and sensitivities with respect to clinical and intra-operative diagnostic standards, for various muscle screens.
  
  
  RESULTS
  Selected 4 muscle EMG screens identified over 97% of EMG confirmed radiculopathies and over 89% of surgically confirmed radiculopathies.
  
  
  CONCLUSIONS
  These findings underscore the utility of 4 muscle EMG screens in the evaluation of patients with suspected lumbosacral radiculopathy.
authors.affiliation: Department of Physical Medicine and Rehabilitation, The Johns Hopkins University, MD, Baltimore, USA. tdilling@jhmi.edu
authors.forename: T R
authors.initials: TR
authors.lastname: Dillingham
authors.forename: K J
authors.initials: KJ
authors.lastname: Dasher
mesh_terms: D004576:Electromyography; D006801:Humans; D009132:Muscles / Q000503:physiopathology*; D012585:Sciatica / Q000503:physiopathology*