High-Yield Summary
- Osteoporotic vertebral compression fractures (OVCFs) primarily affect the anterior column, leading to wedge deformities and sagittal imbalance; early recognition and management prevent chronic disability.
- Non-operative treatment is first-line for stable fractures without neurologic compromise, focusing on pain control, mobilization, and osteoporosis management.
- Indications for surgery include progressive deformity, intractable pain, neurologic deficit, or failure of conservative therapy beyond 6-8 weeks.
- Vertebral augmentation (kyphoplasty or vertebroplasty) offers pain relief and height restoration but is reserved for select patients without posterior wall compromise or canal compromise.
- Instrumented fixation with or without anterior column reconstruction is reserved for unstable fractures, neurologic deficits, or severe kyphosis, requiring careful implant selection due to poor bone quality.
Clinical Fundamentals
Relevant Anatomy and Biomechanics
The vertebral body bears axial load, with the anterior column accounting for approximately 80% of weight transmission. Osteoporotic bone exhibits decreased trabecular density and cortical thinning, predisposing to anterior wedge fractures under axial compression and flexion forces. The posterior elements and ligamentous structures often remain intact in isolated compression fractures, preserving stability unless disrupted. Sagittal balance depends on vertebral height and alignment; loss of anterior height leads to kyphotic deformity, increasing mechanical stress on adjacent segments.
Epidemiology
OVCFs are the most common fragility fractures in the elderly, with incidence rising sharply after age 70. Women are disproportionately affected due to postmenopausal osteoporosis. Many fractures are clinically silent or present with nonspecific back pain, leading to underdiagnosis. The risk of subsequent fractures increases significantly after an initial OVCF, underscoring the importance of systemic osteoporosis treatment.
Classification & Diagnosis
| Classification System | Description | Impact on Management |
|---|---|---|
| Genant Semi-Quantitative | Grades vertebral deformity by height loss: Grade 1 (20-25%), Grade 2 (25-40%), Grade 3 (>40%) | Guides severity assessment; Grade 2-3 may warrant intervention beyond analgesia. |
| AO Spine Thoracolumbar Classification | Type A1 (wedge compression), A2 (split), A3 (incomplete burst), A4 (complete burst) | Differentiates stable from unstable fractures; burst fractures (A3, A4) often require surgery. |
| Denis Classification | Divides vertebra into anterior, middle, posterior columns; instability if middle or posterior column involved | Identifies fractures at risk for neurologic injury; posterior column involvement mandates surgical consideration. |
Diagnostic Pearls
- MRI is the gold standard for acute fracture detection and differentiating acute from chronic fractures via bone marrow edema patterns.
- CT is essential for assessing cortical breach, posterior wall involvement, and canal compromise.
- Beware of missed posterior element fractures on plain radiographs; always correlate clinically and consider advanced imaging.
- Evaluate for neurologic deficits meticulously; subtle signs may indicate retropulsed fragments.
Decision-Making Algorithm
| Criteria | Non-Operative Management | Operative Management |
|---|---|---|
| Stability | Stable fracture with intact posterior elements | Unstable fracture with posterior column disruption |
| Neurologic Status | No neurologic deficit | Progressive or new neurologic deficit |
| Pain | Controlled with analgesics and mobilization | Intractable pain refractory to 6-8 weeks of conservative care |
| Deformity | Minimal kyphosis (<20°) and no progression | Progressive kyphosis >20°, sagittal imbalance |
| Imaging | No canal compromise or retropulsed fragments | Canal compromise, retropulsed fragments causing neural compression |
Surgical Approach and Implant Selection
- Posterior percutaneous instrumentation with cement augmentation is preferred for stabilization in poor bone quality.
- Anterior column reconstruction with cages or structural grafts is indicated for severe vertebral body collapse or burst fractures with canal compromise.
- Vertebral augmentation techniques are reserved for pain relief in stable fractures without neurologic involvement.
- Avoid extensive fusion in elderly patients unless necessary to minimize morbidity.
Surgical Mastery & Pearls
Step-by-Step Conceptual Overview
- Preoperative Planning: Assess bone quality, fracture morphology, and sagittal alignment. Optimize medical comorbidities and osteoporosis treatment.
- Positioning: Prone on a radiolucent table with padding to reduce abdominal pressure and venous engorgement.
- Exposure: For percutaneous fixation, use fluoroscopic landmarks to minimize soft tissue disruption. Open approaches require careful dissection to preserve paraspinal musculature.
- Instrumentation: Use fenestrated pedicle screws with polymethylmethacrylate (PMMA) augmentation to enhance fixation in osteoporotic bone.
- Vertebral Augmentation: Balloon kyphoplasty restores height and reduces kyphosis; avoid in fractures with posterior wall disruption to prevent cement leakage.
- Decompression: Indicated if neurologic deficit is present; perform laminectomy or corpectomy as dictated by canal compromise.
- Fusion: Use autograft or allograft with supplemental instrumentation; limit fusion levels to reduce morbidity.
Intraoperative Red Flags
- Cement extravasation into the canal or venous system during augmentation.
- Pedicle breach on screw insertion, risking neurologic injury.
- Excessive blood loss in open procedures, especially in elderly with comorbidities.
- Failure to restore sagittal alignment leading to persistent deformity.
Evidence-Based Synthesis
Landmark randomized controlled trials have established non-operative management as effective for most stable OVCFs, emphasizing early mobilization and osteoporosis treatment. Vertebral augmentation trials demonstrate significant short-term pain relief and functional improvement but show mixed results regarding long-term outcomes and fracture risk at adjacent levels. Recent meta-analyses suggest kyphoplasty may offer superior height restoration compared to vertebroplasty but with similar complication profiles.
Surgical fixation in unstable fractures with neurologic compromise improves neurologic recovery and prevents deformity progression. Innovations in cement-augmented pedicle screws have reduced hardware failure rates in osteoporotic bone, although long-term data remain limited. Controversy persists regarding the threshold for surgical intervention in borderline cases, highlighting the need for individualized patient assessment.
Master Class Pro-Tip
Mastery in managing OVCFs hinges on integrating biomechanical principles with patient-specific factors: prioritize restoring sagittal balance through targeted anterior column support combined with cement-augmented posterior fixation. Avoid over-instrumentation to reduce morbidity, and employ intraoperative neuromonitoring to detect subtle neurologic compromise early. Meticulous preoperative planning with CT and MRI fusion imaging enhances screw trajectory accuracy and optimizes implant purchase in compromised bone, elevating outcomes beyond standard care.
