Management of Kümmell's Disease (Delayed Post-Traumatic Vertebral Osteonecrosis)
For Kümmell's disease, treatment selection depends on neurological status and spinal stability: patients without neurological deficits should receive percutaneous vertebroplasty or kyphoplasty as first-line treatment, while those with cord compression or significant instability require posterior decompression and stabilization with transpedicular bone grafting. 1, 2
Understanding the Disease Process
Kümmell's disease represents avascular osteonecrosis of a vertebral body that develops months to years after minor spinal trauma in osteoporotic patients, characterized by the pathognomonic intravertebral vacuum cleft sign on imaging. 1, 3 This vacuum phenomenon indicates avascular necrosis and is highly specific for Kümmell's disease, never occurring with malignancy or inflammatory conditions. 4
The disease typically affects the thoracolumbar junction and presents with an initial asymptomatic period followed by progressive pain, kyphosis, and potentially neurological deficits. 1, 2
Diagnostic Imaging Approach
Plain radiographs should be obtained first to identify the intravertebral vacuum cleft sign, which appears as a radiolucent zone within the compressed vertebral body. 1, 4
MRI is essential to visualize the intravertebral fluid collection, assess cord compression, and differentiate from malignancy or infection. 2, 3
CT scanning provides superior visualization of the vacuum cleft and is critical for surgical planning when intervention is needed. 2, 4
Dynamic radiography must be performed to assess intravertebral instability, particularly if initial treatment fails. 5
Treatment Algorithm Based on Clinical Presentation
Stage 1: No Neurological Deficit, Minimal Instability
Percutaneous vertebroplasty (PVP) or kyphoplasty is the primary treatment, providing significant symptomatic relief, functional improvement, and deformity correction. 1, 5
Critical technical consideration: Inject bone cement volume exceeding the intravertebral cleft size to prevent nonunion and persistent instability—insufficient cement volume is the primary cause of PVP failure in Kümmell's disease. 5
Conservative management (bed rest, bracing, lumbar traction, analgesics, and osteoporosis medication) can be attempted in patients refusing surgery, though outcomes are less predictable. 3
Teriparatide (rhPTH 1-34) 20 mcg/day may enhance vertebral fracture healing and reduce vacuum cleft size in osteoporotic patients, though evidence is limited to case reports. 4
Stage 2: Progressive Kyphosis Without Neurological Deficit
Percutaneous vertebral augmentation remains appropriate if the vacuum cleft is accessible and adequate cement fill can be achieved. 1, 5
Surgical stabilization should be considered if kyphosis is severe (>30 degrees) or progressive despite conservative measures. 1
Stage 3: Neurological Deficit or Cord Compression
Posterior decompression with stabilization and transpedicular bone grafting is the definitive treatment, offering short operating time, minimal blood loss, and early recovery. 2
This approach provides neural decompression while restoring spinal column stability through direct bone grafting into the necrotic vertebral body. 2
Anterior, posterior, or combined approaches may be selected based on the location of compression and surgeon experience, though posterior-only approaches are increasingly favored for their lower morbidity. 1
Critical Pitfalls to Avoid
Underestimating cement volume in PVP: The most common cause of failed vertebroplasty is injecting insufficient cement to stabilize the intravertebral nonunion—always exceed the cleft volume. 5
Missing intravertebral instability: If pain persists after PVP, obtain dynamic radiographs to detect cement displacement and residual instability requiring repeat intervention. 5
Delaying diagnosis: The asymptomatic interval between trauma and symptom onset can lead to missed diagnosis—maintain high suspicion in elderly osteoporotic patients with delayed-onset back pain after minor trauma. 3
Inadequate osteoporosis management: All patients require concurrent treatment for underlying osteoporosis to prevent additional fractures. 2, 4
Dismissing neurological symptoms: Progressive weakness or bowel/bladder dysfunction mandates urgent surgical decompression rather than continued conservative management. 2