title: Vertebroplasty and kyphoplasty for cervical spine metastases: a systematic review and meta-analysis.
abstract: BACKGROUND
  Vertebroplasty (VP) and kyphoplasty (KP) are two minimally invasive techniques used to relieve pain and restore stability in metastatic spinal disease. However, most of these procedures are performed in the thoracolumbar spine, and there is limited data on outcomes after VP/KP for cervical metastases. The purpose of this article is to evaluate the safety and efficacy of VP and KP for treating pain in patients with cervical spine metastases.
  
  
  METHODS
  A systematic review of the literature was conducted using the PubMed and Medline databases. Only studies that reported five or more patients treated with VP/KP in the cervical spine were included. Levels of evidence and grades of recommendation were established based on the Oxford Centre for Evidence-Based Medicine guidelines. Data was pooled to perform a meta-analysis for pain relief and complication rates.
  
  
  RESULTS
  Six studies (all level 4 studies) met the inclusion criteria, representing 120 patients undergoing VP/KP at 135 vertebrae; the most common addressed level was C2 in 83 cases. The average volume of injected cement was 2.5 ± 0.5 milliliters at each vertebra. There were 22 asymptomatic cement leaks (16%; 95% CI, 9.8% - 22.2%) most commonly occurring in the paraspinal soft tissue. There were 5 complications (4%; 95% CI, 0.5% - 7.5%): 3 cases of mild odynophagia, 1 case of occipital neuralgia secondary to leak, and 1 case of stroke secondary to cement embolism. Pain relief was achieved in 89% of cases (range: 80 - 100%). The calculated average pain score decreased significantly from 7.6 ± 0.9 before surgery to 1.9 ± 0.8 at last evaluation (p=0.006).
  
  
  CONCLUSIONS
  Although the calculated complication rate after VP/KP in the cervical spine is low (4%) and the reported pain relief rate is approximately 89%, there is lack of high-quality evidence supporting this. Future randomized controlled trials are needed.
authors.affiliation: Tecnológico de Monterrey, School of Medicine and Health Sciences, Monterrey, México; Institute of Neurology and Neurosurgery, Hospital Zambrano Hellion Tecnológico de Monterrey, Monterrey, México.
authors.forename: Rafael
authors.initials: R
authors.lastname: De la Garza-Ramos
authors.affiliation: Tecnológico de Monterrey, School of Medicine and Health Sciences, Monterrey, México; Institute of Neurology and Neurosurgery, Hospital Zambrano Hellion Tecnológico de Monterrey, Monterrey, México; Department of Neurosurgery, Universidad Autónoma de Nuevo León, Monterrey, México.
authors.forename: Mario
authors.initials: M
authors.lastname: Benvenutti-Regato
authors.affiliation: Tecnológico de Monterrey, School of Medicine and Health Sciences, Monterrey, México; Institute of Neurology and Neurosurgery, Hospital Zambrano Hellion Tecnológico de Monterrey, Monterrey, México.
authors.forename: Enrique
authors.initials: E
authors.lastname: Caro-Osorio
keywords: cervical metastases; kyphoplasty; spinal metastases; systematic review; vertebroplasty