title: Selective nerve root injections can predict surgical outcome for lumbar and cervical radiculopathy: comparison to magnetic resonance imaging.
abstract: OBJECTIVE
  Diagnostic selective nerve root injection (SNI) results were analyzed in 101 patients who underwent lumbar or cervical decompression for radiculopathy and compared to surgical outcome 1 year postoperatively. A comparison of surgical outcomes was also examined between magnetic resonance imaging (MRI) and SNI results.
  
  
  RESULTS
  Of the 101 patients, 91 (90%) had positive and 10 had negative SNI results at the level operated. Ninety-one percent of the patients with a positive SNI had good surgical outcomes, whereas 60% of the patients with a negative SNI had good outcomes. Of the patients with a positive MRI result, 87% had good surgical outcomes, whereas a similar percentage of the patients with a negative MRI (85%) had good surgical outcomes. When findings between SNI and MRI differed (n = 20), surgery at a level consistent with the SNI was more strongly associated with a good surgical outcome. Of the patients with a poor surgical outcome, surgery was most often performed at a level inconsistent with the SNI finding.
  
  
  CONCLUSIONS
  Our study found that a diagnostic SNI can safely and accurately discern the presence or absence of cervical or lumbar radiculopathy. The diagnostic SNI can persuade surgeons from operating on an initially suspicious, but incorrect, level of radiculopathy. In cases where MRI findings are equivocal, multilevel, and/or do not agree with the patient's symptoms, the result of a negative diagnostic SNI (ie, lack of presence of radiculopathy) becomes superior in predicting the absence of an offending lesion.
authors.affiliation: Indiana Spine Group and Clinical Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, Indiana 46260, USA. rsasso@on-net.net
authors.forename: Rick C
authors.initials: RC
authors.lastname: Sasso
authors.forename: Kevin
authors.initials: K
authors.lastname: Macadaeg
authors.forename: Daniel
authors.initials: D
authors.lastname: Nordmann
authors.forename: Mark
authors.initials: M
authors.lastname: Smith
mesh_terms: D000779:Anesthetics, Local / Q000008:administration & dosage; D001416:Back Pain / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control; D002574:Cervical Vertebrae / Q000601:surgery; D019299:Decompression, Surgical / Q000379:methods*; D006801:Humans; D007267:Injections; D008159:Lumbar Vertebrae / Q000601:surgery; D008279:Magnetic Resonance Imaging; D009407:Nerve Block / Q000379:methods*; D010147:Pain Measurement / Q000379:methods; D011379:Prognosis; D011843:Radiculopathy / Q000150:complications / Q000175:diagnosis* / Q000601:surgery*; D013126:Spinal Nerve Roots / Q000187:drug effects*; D016896:Treatment Outcome
chemical_list: D000779:Anesthetics, Local