osteoporotic spinal compression fracture
Osteoporotic spinal compression fractures occur as a result of injury, commonly fall onto the buttock or pressure from normal activities, to the weakened vertebrae due to osteoporosis.
They have a reported incidence of 1.2 per 1000 person-years after 85 years of age in the United States. However, they are largely unreported and are probably more common radiographically (present up to 14% of women older than 60 years in one study ).
Vertebral fractures present with pain and loss of mobility.
Vertebral fractures require treatment when they are symptomatic, i.e. with pain and loss of mobility. This defines the role of the radiologist in making an accurate diagnosis.
The vertebral fracture should be diagnosed when there is a loss of height in the anterior, middle, or posterior dimension of the vertebral body that exceeds 20%. When in doubt, it is recommended that additional views or studies be advised for confirmation.
Osteoporotic spine fractures can be graded based on vertebral height loss as:
- mild: up to 20-25%
- moderate: 25-40%
- severe: >40%
Also, see Genant classification of vertebral fractures.
Acute vs chronic
Chronicity of the fracture indicates its temporal relationship with symptoms and hence is an important determination.
On conventional imaging, acute fracture signs include cortical breaking or impaction of trabeculae; in the absence of these signs fractures are chronic.
In uncertain cases, MRI signs of edema (acute) and presence of radiotracer uptake on bone scintigraphy (acute) help decide the age of the fracture.
Osteoporotic vs pathological
Discriminating between acute osteoporotic fracture and pathological fracture is sometimes challenging.
The following features favor the diagnosis of a benign compression fracture:
- no bony destruction
- preserved normal fatty bone marrow T1WI signal
- low signal intensity band on T1WI and T2WI indicating a fracture line
- fluid sign
- retropulsion (not posterior bulging) of the posterosuperior cortex of the vertebral body
- no epidural mass
- multiple compression fractures
Treatment and prognosis
Management options include:
- medications: bisphosphonates for osteoporosis
- spinal fracture index
- spine deformity index
- radiological vertebral index