Considerable useless distinction has been made between 'fracture' and 'dislocation' of the vertebrae. The use of X-ray technology has shown that nearly all spinal fractures are complicated by at least some articular displacement, and dislocations rarely occur without fracture of some portion of the vertebrge. This close association renders the term 'fracture-dislocation' most accurate. Dislocations uncomplicated by fracture are sometimes seen in the cervical spine but almost never in lower portions. The importance lies not in bony injury but potential damage to the spinal cord and nerves. Diagnosis and treatment come under neurology, necessitating cooperation with a neurologist.
The character of vertebral bone structure is crucial for understanding deformities in fracture-dislocations. Vertebral bodies are cancellous with compact tissue on the surface; arches have heavy compact tissue. Compression strains lead to body collapse while arch fractures are clean-cut. Hyperflexion strain causes crushing of vertebrae bodies, resulting in kyphosis. Cervical spine articular surfaces allow for more dislocations due to less firm interlocking compared to other regions.
In Pott's disease, vertebral bodies give way under normal strain; in fracture with kyphosis, they collapse from excessive strain. Dorsal region articular surfaces are at right angles, making sliding one vertebra on another nearly impossible without producing fractures. Lumbar region articular surfaces are also nearly perpendicular but correspond more closely to the sagittal plane.
The spinal cord lies within the canal extending downward from foramen magnum to about L2. The level of the lower end varies in different persons, explained by growth differences between column and cord. Early foetal arrangement sees spinal nerves arising directly from the cord; later, they have a downward intraspinal course varying with nerve level.
The dura forms a well within the canal extending to about S3, suspending the cord surrounded by cerebrospinal fluid. Injury is almost impossible if the column remains intact due to steady ligaments and nerves preventing contact with canal walls. Tracts in the cord do not regenerate after injury or disease; spinal nerves can regenerate under favorable conditions.
Symptoms of fracture include local pain, abnormal mobility, crepitus, deformity, loss of function. Symptoms from cord/nerves: shock (unconsciousness in cervical fractures), changes in pulse/temp/respiration, motor/sensory disturbances, reflex/trophic changes. Pain is present at the seat of fracture and increased by motion; severe cases may cause syncope.
Deformity varies with region injured and nature/degree of fracture. Kyphosis is often pronounced enough to be recognized by inspection alone. Loss of function is inevitable in spinal column fractures, varying according to injury severity. Shock accompanies all uncomplicated fractures and is augmented when the cord is injured. <Callout type="warning" title="Danger">Attempting to elicit crepitus for diagnostic purposes can cause severe damage to the spinal cord or nerves.</Callout> Symptoms following injury to the cord/nerves vary with completeness/region of injury. Slight pressure on the spinal cord may produce irritation leading to degeneration if not relieved; destruction of tissue is always followed by loss of function.
Motor disturbances at and below seat of fracture are common when cord injured, varying according to nature/region/completeness of lesion. In complete crushing paralysis will be found in parts supplied by damaged segments; partial injury shows flaccid paralysis in injured segments with spasticity in lower ones.
Key Takeaways
- Fracture-dislocation is a more accurate term for spinal injuries due to the close association of fractures and dislocations.
- Understanding vertebral bone structure is crucial for diagnosing deformities in fracture-dislocations.
- Cooperation with neurologists is essential when dealing with spinal injuries.
Practical Tips
- Always suspect spinal injury if there's neck pain, deformity, or loss of function following trauma.
- Avoid unnecessary manipulation to prevent further damage to the spinal cord and nerves.
Warnings & Risks
- Attempting to elicit crepitus for diagnostic purposes can cause severe damage to the spinal cord or nerves.
- Shock accompanies all uncomplicated fractures and is augmented when the cord is injured.
Modern Application
While this chapter's medical terminology and treatment approaches are outdated, its emphasis on accurate diagnosis through X-ray imaging and the importance of neurology in managing spinal injuries remains relevant. Modern emergency responders should still be cautious about unnecessary manipulation and seek neurological consultation.
Frequently Asked Questions
Q: Why is it important to have a neurologist involved when dealing with spinal fractures?
Spinal fractures often involve damage to the spinal cord or nerves, necessitating specialized knowledge in neurology for proper diagnosis and treatment.
Q: What are some key symptoms of spinal fracture-dislocation?
Key symptoms include local pain, abnormal mobility, crepitus, deformity, loss of function, shock, changes in pulse/temp/respiration, motor/sensory disturbances, reflex/trophic changes.
Q: How does the anatomy of the cervical spine differ from other regions?
The cervical spine has less firm interlocking between vertebrae compared to other regions, allowing for more dislocations without fractures. Articular surfaces are also more parallel in the cervical region.