Vertebral Augmentation for Compression Fractures Scott Magnuson, MD Pain Management of North Idaho, PLLC
OVCFs are most common type of fragility fracture 20-25% Caucasian women and men over 50 yrs have a prevalent vertebral fracture 1/5 women with a VF will sustain another withing 12 months - the fracture cascade Risk of future VCFs increases with number of prior VCFs In women over 80, 50% have a prevalent VCF
VCFs lead to severe spinal deformity, back pain, loss of height, immobility, depression, increased number of bed days, reduced pulmonary function and premature death VCFs associated with 8 fold increase in mortality (similar to hip fractures) Financial burden is high In US, nearly 2 million VCFs per year costing close to $17 billion
Leading cause of VCF is osteoporosis Risk of VCF doubles for every SD below avg vertebral bone mineral density
Osteoporosis Low bone mass Deterioration in the micro architecture or bone tissue Osteoporosis occurs when loss > replacement = net loss of bone strength Silent disease Affects all bones Fractures - vertebrae, wrist, hip VCF most common type of osteoporotic fracture
Pathophysiology of OVCF Two types of bone: Cortical (compact) - 80% - shafts of long bones and outer surfaces of flat bones Trabecular (cancellous) - ends of long bones, inner parts of flat bones, vertebrae
OVCF Generally occur earlier in life than hip fractures Under reported Appropriate intervention is often not initiated (30%) Reasons Generally doesn t require emergency care Patients think their back pain due to arthritis, muscle strain HCP does not recognize signs VCFs not always painful VCFs can be slow onset
OVCF Typical signs Loss of height Sudden severe back pain in the mid and lower spine Increased stoop (Dowager s hump)
OVCF - Classification Wedge-shaped (anterior) Biconcave (middle) Crush (posterior) Complete (both anterior and posterior)
OVCF - Diagnostic testing X-rays (initial workup) CT scan (Pro = evaluate anatomy and assess loss of height, bone fragments, canal compromise. Con = expense, radiation exposure) MRI (Pro = age of fracture, neural compromise) STIR Post-contrast MRI (detect pathologic fracture) DEXA
OVCF - Management Medical NSAIDs, MRs, opioids, neuropathic pain agents, local analgesic patch, ICNBs, TENS PT Strengthening of supportive musculature, proprioception reflexes to improve posture, ambulation, and decrease risk of future falls Bracing
CM for 4-6 weeks OVCF - Surgical management Continued unremitting pain or extreme pain earlier deserves consideration for surgical management Subacute phase (< 6 months) Significant pain & tenderness IN THE FRACTURE AREA Increased pain with mechanical axial loading Absence of complete collapse
Contraindications OVCF - Surgical management Incompetency or fracture through posterior wall Bony retropulsion (with/without neural compromise) Osteomyelitis at fracture site Allergies to cement Ability to tolerate prone position and sedation/anesthesia Adequate cardiac and pulmonary status, especially for multiple fractures
Vertebral Augmentation Vertebroplasty Kyphoplasty
Vertebroplasty Minimally invasive Fluoroscopically guided Injection of PMMA into VB
Vertebroplasty Outpatient procedure Conscious sedation + local anesthesia Prophylactic antibiotics Prone position Use of fluoroscopy (2)
What happens with vertebral augmentation? Increase stiffness and strength of fractured VB Compressive and bending stiffness of motion segment partially restored Increase vertebral height Decrease wedge angle Augmented VBs show improved fatigue properties
Augmented vertebral bodies help to restore function. End plate deformity is reduced leading to more normal nucleus pressure with compressive load and decreasing stress on posterior vertebral column. This suggests a decreased risk for recurrent and adjacent level fractures.
Factors influencing mechanical efficacy of VA Characteristics of procedure Cement type Volume Distribution Characteristics of the spine BMD Disc degeneration Damage severity
VP vs KP In vitro studies show KP achieves better height restoration and wedge angle (lost during subsequent cycle loading) Both VP and KP restore MS stiffness, intradiscal pressure and spinal load sharing by a similar amount Both give the same pain relieving effect
A Randomized Controlled Trial of Vertebroplasty for Osteoporotic Spine Fractures N Engl J Med, 2009 August 6; 361(6): 569-579 RCT of VP vs sham procedure Primary endpoints = change in RMDQ and avg pain intensity ratings in previous 24 hours. Allowed to crossover at 1 month No difference at 1 month between groups. Trend toward meaningful pain relief in VP group Limitations: Study had difficulty recruiting (patients with more pain, worse fx opt out?) No details on levels, how long avg pain present, etc 12% of VP group crossed over after 1 month vs 43% of control group
Impact of Nonoperative Treatment, Vertebroplasty, and Kyphoplasty on Survival and Morbidity after vertebral compression fracture in the Medicare population, Chen et al, The Journal of Bone and joint Surgery, 2013: 95:1729-36 Vertebral augmentation associated with longer patient survival than non-operative treatment KP better than VP (3 year survival rate 59.9% vs 49.7%)
Vertebroplasty and kyphoplasty for the treatment of vertebral compression fractures: an evidenced-based review of the literature McGirt MJ et al, Spine J, 2009, Jun; 9(6):501-8 All articles between 1980-2008 reporting outcomes after VP or KP Level I evidence = VP results in less analgesia use, less disability, and greater improvement in general health when compared with optimal medical management within the first 3 months after intervention Level II-III evidence = by 2 years after intervention, VP provides similar degree of pain control and physical function as optimal medical management Level II-III evidence = KP results in greater improvement in daily activity, physical function, and pain relief when compared with optimal medical Management
Vertebroplasty versus conservative treatment in acute osteoporotic vertebral compression fractures (Vertos II): an open-label randomised trial Lancet, 2010 Sep 25;376(9746):1085-92 431 patients eligible for randomization 229 experience spontaneous relief during workup 202 randomly allocated 101 vertebroplasty 101 conservative treatment Pain relief after VP is immediate, is sustained for at least a year, and is significantly greater than that achieved with conservative treatment, at an acceptable cost
A randomized trial comparing balloon kyphoplasty and vertebroplasty for vertebral compression fractures due to osteoporosis Am J Neuroradiol, 2014, Open access Published October 9, 2014 as 10.3174/ajar.A4127 OVCF, 1-3, T5-L5, KP vs VP 12 and 24 month subsequent radiographic fracture incidence was the primary endpoint Both provide similar sustained improvement in pain, disability and QOL for 2 years with similar AEs. No difference between the 2 groups. Procedure duration and hospitalization shorter in VP KP had fewer cement leakages, a trend of longer fracture-free survival, and less loss of kyphotic-deformity correction
Final Thoughts VP and KP can lead to lower morbidity and mortality in patients with painful OVCFs who have failed CMM Inclusion criteria include significant pain AT the fracture site, evidence of acute to subacute fracture, and decreased function secondary to the fracture Risk of adverse events is low KP may potentially be associated with less adjacent fracture risk and better kyphotic-deformity correction than VP