title: Incidence and prognostic factors of c5 palsy: a clinical study of 1001 cases and review of the literature.
abstract: BACKGROUND
  C5 palsy is a known cause of postoperative deltoid weakness. Prognostic variables affecting the incidence of the palsy have been poorly understood.
  
  
  OBJECTIVE
  To determine the incidence and perioperative characteristics/predictors of C5 palsy after anterior vs posterior operations.
  
  
  METHODS
  All patients undergoing C4-5 operations for degenerative conditions were retrospectively reviewed over 21 years. Anterior operations included an anterior cervical discectomy and fusion (ACDF) or a corpectomy, whereas posterior operations included laminectomy and fusion (± foraminotomies).
  
  
  RESULTS
  Of the total 1001 operations, in 49.0% anterior and 51.0% posterior cases, there was an overall C5 palsy incidence of 5.2% (52 cases): 1.6% and 8.6%, respectively (P < .001). Of the 99 corpectomies, the palsy incidence of 4.0% was not only higher than ACDFs (1.0%), but also followed an upward trend with increasing corpectomy levels (P = .009). Of the 69 posterior and 83 anterior C4-5 foraminotomies, the incidence of C5 palsy was statistically higher in the posterior (14.5%) vs anterior (2.4%) cohort (P = .01). Multiple logistical regression identified older age as the strongest predictor of C5 palsy in the anterior (P = .02) and C4-5 foraminotomy in the posterior (P = .06) cohort. This condition improved within 3 to 6 months in 75% of patients in the anterior and 88.6% in the posterior cohort after a mean follow-up of 14.4 and 27.6 months, respectively.
  
  
  CONCLUSIONS
  In one of the largest cohorts on C5 palsy, we found in anterior operations an increasing number of corpectomy levels had a higher incidence of C5 palsy; however, older age was the strongest predictor of C5 palsy. In posterior operations, C4-5 foraminotomy carried the strongest correlation.
authors.affiliation: ‡Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland; §Johns Hopkins Spinal Biomechanics and Surgical Outcomes Laboratory, Baltimore, Maryland.
authors.forename: Mohamad
authors.initials: M
authors.lastname: Bydon
authors.forename: Mohamed
authors.initials: M
authors.lastname: Macki
authors.forename: Paul
authors.initials: P
authors.lastname: Kaloostian
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Sciubba
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Wolinsky
authors.forename: Ziya L
authors.initials: ZL
authors.lastname: Gokaslan
authors.forename: Allan J
authors.initials: AJ
authors.lastname: Belzberg
authors.forename: Ali
authors.initials: A
authors.lastname: Bydon
authors.forename: Timothy F
authors.initials: TF
authors.lastname: Witham
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D019299:Decompression, Surgical / Q000009:adverse effects / Q000379:methods; D005260:Female; D006801:Humans; D015994:Incidence; D007796:Laminectomy / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D010243:Paralysis / Q000453:epidemiology* / Q000601:surgery*; D011183:Postoperative Complications / Q000453:epidemiology*; D011379:Prognosis; D012189:Retrospective Studies; D012196:Review Literature as Topic; D013123:Spinal Fusion / Q000009:adverse effects; D013126:Spinal Nerve Roots / Q000601:surgery