title: Incidence and risk factors of C5 palsy following posterior cervical decompression: a systematic review.
abstract: BACKGROUND
  C5 palsy is a serious but poorly understood complication after posterior cervical decompression that could lead to muscle weakness, brachialgia and numbness of the upper limbs. The incidence of C5 palsy varies greatly between studies. The risk factors are inconclusive and even conflicting.
  
  
  OBJECTIVE
  To perform a systematic review on the incidence and risk factors of C5 palsy after posterior cervical decompression.
  
  
  METHODS
  Four databases, PubMed, Embase, Web of Science and Cochrane CENTRAL, were searched to identify eligible studies. Either a fixed- or a random-effects model was used to calculate the pooled odd ratio (RR) or standardized mean difference (SMD) with its 95% confidence interval (95%CI).
  
  
  RESULTS
  Of the 589 pre-recruited studies, 25 were included in this study for systematic review. The pooled incidence of C5 palsy after posterior decompression was 5.8% (95%CI: 4.4-7.2%). The incidence after open-door laminoplasty, double-door laminoplasty and laminectomy was 4.5%, 3.1% and 11.3%, respectively. The significant risk factors of C5 palsy were OPLL (OR, 2.188; 95%CI, 1.307-3.665), narrower intervertebral foramen (SMD, -0.972; 95%CI, -1.398 to -0.545), laminectomy (vs. open-door laminoplasty, OR, 2.988; 95%CI, 1.298-6.876), excessive spinal cord drift (SMD, 1.289, 95%CI, 0,197-2.381) and male gender (OR, 1.54; 95%CI, 1.036-2.301).
  
  
  CONCLUSIONS
  The results of this systematic review suggest that patients with excessive spinal cord drift, preexisting intervertebral foramenal stenosis, OPLL, laminectomy and male gender are at high risk for postoperative C5 palsy, and risk-reduction options should be considered for such patients.
authors.affiliation: Department of Spine Surgery, Changzheng Orthopedic Hospital, Second Military Medical University, Shanghai, China.
authors.forename: Yifei
authors.initials: Y
authors.lastname: Gu
authors.affiliation: Department of Spine Surgery, Changzheng Orthopedic Hospital, Second Military Medical University, Shanghai, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Cao
authors.affiliation: Department of Spine Surgery, Changzheng Orthopedic Hospital, Second Military Medical University, Shanghai, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Gao
authors.affiliation: Department of Spine Surgery, Changzheng Orthopedic Hospital, Second Military Medical University, Shanghai, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Tian
authors.affiliation: Department of Spine Surgery, Changzheng Orthopedic Hospital, Second Military Medical University, Shanghai, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Liang
authors.affiliation: Department of Spine Surgery, Changzheng Orthopedic Hospital, Second Military Medical University, Shanghai, China.
authors.forename: Ce
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Spine Surgery, Changzheng Orthopedic Hospital, Second Military Medical University, Shanghai, China.
authors.forename: Lili
authors.initials: L
authors.lastname: Yang
authors.affiliation: Department of Spine Surgery, Changzheng Orthopedic Hospital, Second Military Medical University, Shanghai, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Yuan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002574:Cervical Vertebrae / Q000473:pathology / Q000601:surgery; D019299:Decompression, Surgical / Q000009:adverse effects*; D005260:Female; D006801:Humans; D015994:Incidence; D007796:Laminectomy / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D010243:Paralysis / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology; D012307:Risk Factors; D012737:Sex Factors; D013126:Spinal Nerve Roots / Q000473:pathology / Q000601:surgery