title: Fracture risk of vertebral bodies after cryosurgery using a miniature cryoprobe: A biomechanical in-vitro analysis on human bones.
abstract: BACKGROUND
  Due to spinal instability and compressive neurologic deficits surgical management is sometimes necessary in patients with metastatic spinal lesions. However, in some cases open surgery is not possible and minimally invasive procedures, like cryoablation, are needed. The aim of the current study was to investigate whether a miniature cryoprobe provides adequate tissue cooling in vertebrae and to evaluate the direct impact of cryosurgery on vertebral body stability.
  
  
  METHODS
  Twelve thoracic vertebral bodies were harvested from fresh cadavers. After documenting bone density cryoablation was performed in six vertebral bodies according to a standardized procedure. Afterwards temperature inside the vertebral body and maximum breaking force were measured in the control and experimental groups.
  
  
  RESULTS
  Required temperature of -50° was reached in all areas. There was a significant correlation between maximum breaking force and measured bone density (p= 0.001). Mean breaking force within the experimental group was 5047 N (SD = 2955 N) compared to 4458 N (SD = 2554 N) in the control group. There were no observable differences in maximum breaking force between both groups.
  
  
  CONCLUSIONS
  Miniature cryoprobe can deliver adequate tissue cooling to -50°C in vertebral bodies. The procedure does not seem to influence breaking force of the treated bones in-vitro. Therefore, using miniature probes cryosurgery may provide a valuable alternative to conventional surgical resection of neoplastic diseases as well as of benign locally aggressive bone tumors.
authors.affiliation: Centre for Orthopaedic and Trauma Surgery, University Medical Centre, Cologne, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Zarghooni
authors.affiliation: Centre for Orthopaedic and Trauma Surgery, University Medical Centre, Cologne, Germany.
authors.forename: L
authors.initials: L
authors.lastname: Westermann
authors.affiliation: Department of Orthopedics, Medical Center City Aachen GmbH, Wuerselen, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Sobottke
authors.affiliation: Centre for Orthopaedic and Trauma Surgery, University Medical Centre, Cologne, Germany.|Centre for Orthopaedics, University Medical Centre, Halle (Saale), Germany.
authors.forename: M
authors.initials: M
authors.lastname: Röllinghoff
authors.affiliation: Centre for Orthopaedic and Trauma Surgery, University Medical Centre, Cologne, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Bredow
authors.affiliation: Centre for Orthopaedic and Trauma Surgery, University Medical Centre, Cologne, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Siewe
authors.affiliation: Centre for Orthopaedic and Trauma Surgery, University Medical Centre, Cologne, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Eysel
authors.affiliation: Centre for Orthopaedic and Trauma Surgery, University Medical Centre, Cologne, Germany.
authors.forename: M J
authors.initials: MJ
authors.lastname: Scheyerer
mesh_terms: D002102:Cadaver; D003452:Cryosurgery / Q000295:instrumentation*; D005260:Female; D050723:Fractures, Bone / Q000209:etiology*; D006801:Humans; D066298:In Vitro Techniques; D008159:Lumbar Vertebrae / Q000503:physiopathology* / Q000601:surgery*; D008297:Male; D011184:Postoperative Period; D018570:Risk Assessment; D013120:Spinal Cord Neoplasms / Q000601:surgery*
keywords: Cryoablation; breaking force; metastatic spinal lesion; miniature cryoprobes