Vertebroplasty



Vertebroplasty


Donald V. La Barge, III, MD










Sagittal graphic represents 2-level compression fractures image of the lower thoracic spine. Note the vertical cleft image predisposing to PMMA cement extravasation into intervertebral disc spaces above and below.






Lateral fluoroscopic spot radiograph in a patient with T8 and T9 osteoporotic compression fractures image shows unipedicular access to each vertebral body, which was achieved with needle tip image in anterior 1/3 of vertebrae.


TERMINOLOGY


Abbreviations



  • Polymethylmethacrylate (PMMA)


Definitions



  • Percutaneous cement augmentation of fractured vertebral body


PRE-PROCEDURE


Indications



  • Symptomatic vertebral fracture refractory to medical management



    • Osteoporotic, post-traumatic, pathologic


  • Impending vertebral fracture



    • Osteoporotic, pathologic


Contraindications



  • Coagulopathy


  • Inability to tolerate prolonged prone positioning



    • May require anesthesiology consultation


  • Relative



    • Pregnancy



      • Teratogenic effects of ionizing radiation


Pre-Procedure Imaging



  • Evaluate



    • Cause of fracture(s)



      • Features of pathologic vs. osteoporotic



        • Imaging features on CT/MR


        • Clinical history of malignancy


    • Level(s) suspected of requiring treatment


    • Retropulsion into spinal canal


  • STIR MR provides excellent depiction of bone marrow edema in acute fracture



    • Radionuclide bone scan is helpful in patients unable to undergo MR


Getting Started



  • Things to check



    • Clinical examination



      • Consistent with imaging findings



        • Point tenderness over spinous process, generally without lower extremity radiculopathy


    • Informed consent


  • Medications



    • Local anesthetic


  • Equipment list



    • Radiopaque marker



      • To mark skin entry site


    • Sterile prep and drape materials


    • Scalpel


    • 10 mL syringe and long 25-gauge needle for application of local anesthetic



      • 22-gauge spinal needle is often helpful to anesthetize cortex of pedicle(s)


    • 2 pedicle access needles per level to be intervened upon



      • Unipedicular access may suffice


    • Support device for access needle



      • Many manufacturers provide long support handle


      • Long clamps are also sufficient


    • Mallet


    • PMMA bone cement


    • Cement mixer



      • If applicable (varies by vendor)


    • Cement injector



      • 1 per vertebral level


    • Injector extension stylette (not part of most kits)



      • Hollow tube that attaches to cement delivery system


      • Fill with cement then advance through pedicle access stylette


    • Hydrogen peroxide



      • Skin cleanser after procedure


    • Steri-strips (Nexcare; St. Paul, Minnesota) and sterile dressing


PROCEDURE


Patient Position/Location



  • Best procedure approach



    • Prone




      • C-arm angled obliquely toward pedicle to be accessed



        • Looking “down the barrel” through pedicle to vertebral body


      • Biplane affords advantage of continuous monitoring of needle depth on lateral fluoroscopy


Equipment Preparation



  • Draw 10 mL local anesthetic, and attach long 25-gauge needle



    • Have 22-gauge spinal needle available for deep injection to include pedicle cortex


  • Ensure all equipment for vertebroplasty is immediately available in desired quantity and sizes



    • Single-level procedure requires at minimum



      • 2 pedicle access needles


      • 1 cement injector


      • PMMA cement with cement mixer (as applicable)



        • Do not mix cement until needle(s) are positioned and fluoroscopy is set to monitor injection


  • Angle C-arm for maximal visualization of pedicle to be accessed



    • Should see all margins of pedicle in ovoid configuration


  • Set true lateral view, if using biplane fluoroscopy, to aid in determining needle angulation and depth


  • Will vertebral biopsy be performed prior to vertebroplasty?



    • Have biopsy system available


    • Procedure in place for proper specimen handling


  • Will vertebral augmentation (cavity creation) be performed prior to vertebroplasty?



    • Ensure compatibility of pedicle access needle with augmentation device


Procedure Steps



  • Procedure “time out”



    • Correct patient, level(s), and procedure to be performed


    • All necessary equipment compatible and available in necessary sizes


  • Initiate conscious sedation/general anesthetic


  • Carefully reassess proper level for intervention


  • Mark skin


  • Perform sterile prep and drape


  • Apply local anesthetic



    • Create skin wheal


    • Anesthetize deep subcutaneous tissue, pedicle cortex



      • Localize 25-gauge or spinal needle under fluoroscopy to level of central pedicle


  • Make skin incision to accommodate pedicle needle


  • Anchor pedicle needle in subcutaneous tissue


  • Attach clamps or manufacturer’s extension handle to pedicle needle


  • Carefully advance pedicle needle to central/lateral portion of vertebral pedicle under fluoroscopy


  • Ensure favorable needle trajectory on both oblique and lateral views prior to gaining osseous purchase



    • Parapedicular, or more lateral starting point in pedicle, allows one to reach &/or cross midline in anterior 1/3 of vertebra



      • Facilitates unipedicular access


    • Ensure constant visualization of medial pedicle cortex


  • Carefully anchor needle in pedicle


  • Incrementally advance needle through pedicle under intermittent oblique and lateral fluoroscopy



    • Ensure that medial pedicle cortex is not violated



      • When tip is close to medial cortex on frontal view, it should be at or entering posterior vertebral body on lateral view


    • Attention to technique is critical to avoid sudden plunging of the needle due to improper control &/or aggressive manipulation



      • Pinching of needle between fingers and thumb of nondominant hand while carefully advancing with dominant hand serves as a “brake” against sudden advancement


    • Use of mallet may be advantageous with nonthreaded access needles


  • Once needle is clearly within vertebral body on lateral view, switch to frontal and lateral views for further needle advancement



    • Better assessment of tip position relative to midline on frontal view



      • Goal is midline or crossing midline for unipedicular injection



    • Depth best assessed on lateral view


  • When needle is within anterior 1/3 of vertebral body, reassess position on direct AP and lateral fluoroscopy
    Only gold members can continue reading. Log In or Register to continue

    Related Posts

Sep 22, 2016 | Posted by in EMERGENCY RADIOLOGY | Comments Off on Vertebroplasty
Premium Wordpress Themes by UFO Themes