title: The effect of pulsed jet lavage in vertebroplasty on injection forces of polymethylmethacrylate bone cement, material distribution, and potential fat embolism: a cadaver study.
abstract: METHODS
  In vitro testing of vertebroplasty techniques including pulsed jet-lavage for fat and marrow removal in human cadaveric lumbar and thoracic vertebrae.
  
  
  OBJECTIVE
  To develop jet-lavage techniques for vertebroplasty and investigate their effect on cement distribution, injection forces, and fat embolism.
  
  
  BACKGROUND
  The main complications of cement vertebroplasty are cement leakage and pulmonary fat embolism, which can have fatal consequences and are difficult to prevent reliably by current vertebroplasty techniques.
  
  
  METHODS
  Twenty-four vertebrae (Th8-L04) from 5 osteoporotic cadaver spines were grouped in triplets depending on bone mineral density (BMD). Before polymethylmethacrylate (PMMA) vertebroplasty, a pulsatile jet-lavage for removal of intertrabecular fat and bone marrow was performed in 2 groups with 8 specimens each, performing radial and axial irrigation from the biopsy needles. One hundred mL of Ringer solution were injected through 1 pedicle and regained by low vacuum via the contralateral pedicle. Eight control vertebrae were not irrigated. All specimens underwent standardized PMMA cement augmentation injecting 20% of the vertebral volume. Injection forces, cement distribution, and extravasations were quantified.
  
  
  RESULTS
  All irrigation solution could be retrieved with the vacuum applied. A Kruskal-Wallis test revealed significantly higher injection forces of the control group as compared with the irrigated groups (P = 0.021). Dilatation of the syringe at forces above 300 N occurred in 75% of the untreated compared with 12.5% of the lavaged specimens. CT distribution analysis showed more homogenous cement distribution of the cement and significantly less extravasation in the irrigated specimens.
  
  
  CONCLUSIONS
  The developed lavage technique for vertebroplasty showed to be feasible and reproducible. The reduction of injection forces would allow the use of more viscous PMMA cement lowering the risk for cement embolization and results in a safer procedure. The wash-out of bone marrow and the possible reduction of pulmonary fat embolism have to be verified with in vivo models.
authors.affiliation: Inselspital, Department of Orthopaedic Surgery, University of Berne, Berne, Switzerland. lorin.benneker@insel.ch
authors.forename: Lorin M
authors.initials: LM
authors.lastname: Benneker
authors.forename: Paul F
authors.initials: PF
authors.lastname: Heini
authors.forename: Norbert
authors.initials: N
authors.lastname: Suhm
authors.forename: Armando
authors.initials: A
authors.lastname: Gisep
mesh_terms: D001843:Bone Cements / Q000009:adverse effects / Q000494:pharmacology*; D015519:Bone Density; D001851:Bone Diseases, Metabolic / Q000378:metabolism / Q000601:surgery; D002102:Cadaver; D004620:Embolism, Fat / Q000209:etiology*; D006801:Humans; D006874:Hydrostatic Pressure; D007322:Instillation, Drug; D008159:Lumbar Vertebrae / Q000601:surgery; D008422:Materials Testing; D019904:Polymethyl Methacrylate / Q000008:administration & dosage* / Q000009:adverse effects; D011183:Postoperative Complications; D013904:Thoracic Vertebrae / Q000601:surgery; D054854:Vertebroplasty / Q000009:adverse effects / Q000379:methods*
chemical_list: D001843:Bone Cements; D019904:Polymethyl Methacrylate