Thoracic and Lumbosacral Spinal Injuries
|Thoracic & Lumbar Spine Injuries|
Mechanism of Injury
• Fall from a height.
• RTA: Seat belt injury (chance fracture).
• Other causes like gunshot injuries, assault, etc.
Mc Afee’s Classification—3-Column Classification
Isolated failure of anterior column due to forward flexion. No neurological deficit.
Stable Burst Fractures
Anterior and middle columns fail. No loss of integrity of posterior elements.
Unstable Burst Fractures
Anterior,Posterior and middle column fail in compression. Post-traumatic kyphosis and neural symptoms are present.
Chance Fracture (Seatbelt injury)
It is seen in people who wear a lap belt without a shoulder harness. Horizontal avulsion fracture of vertebral bodies caused by flexion about an axis anterior to the anterior longitudinal ligament. A strong tensile force pulls entire vertebrae apart.
Flexion Distraction Injury
Flexion axis is posterior to the anterior longitudinal ligament. Anterior column fails in compression. Middle and posterior columns fail in tension. It is unstable because supraspinous, interspinous and ligamentum flavum fail.
Malalignment of neural canal- totally disrupted. All three columns fail in shear. At the affected level, one part of sacral canal- displaced in the transverse plane.
|Spine Cord Ending|
Modified Magerl Classification (AO/ASIF)
Type A: Compression varieties:
Type B: Distraction:
• Through posterior soft tissues (subluxation).
• Through the posterior arch (chance fracture).
• Through the anterior disk.
Type C: Multidirectional with translation:
• Anteroposterior dislocation.
• Lateral (lateral shear fracture).
• Rotational (rotational burst).
The patient gives history of trauma due to RTA or fall from a height and complains of pain; posterior swelling, tenderness, palpable interspinous gap or a step may be felt. Neurological involvement may vary from paraplegia to individual nerve root involvement.
Spinal shock is present for 24 hours during which all the reflexes are lost. Cauda equina paralysis is present if the lesion is below L1. Exaggerated lumbar lordosis may be seen in old cases.
Radiography of the affected spine are taken all three views (AP, lateral and oblique). Fracture of the vertebral body, pedicles, lumbar transverse process, pedicles spinous process, etc. Disk space and neural canal narrowing is looked for.
CT scan and MRI are found to be more useful than radiographs in evaluation of spinal trauma.
This is discussed under two heads.
Management at the site of accident: This consists of careful handling of the patient suspected to have spine injury. Consider all patients with spine injury to have neurological damage, shift them to the hospital with utmost care, and caution avoiding all unnecessary movements.
Definitive treatment at the hospital: The examination and the management measures practiced at the casuality are as follows
Practice: Caution in handling the neck.
Examination: The general condition and other systems like CNS/CVS/RS/PA/GI tract, etc. Also, examine from head to toe, the presence of other fractures, head, chest injuries, blunt injury abdomen and pelvic fractures.
Evaluate: The spine injury by gentle careful clinical examination. This has to be supplemented by proper investigations like X-ray, CT-scan, MRI, etc.
Assess: Carefully assess the level and extent of neurological damage by examining the dermatome, myotome and reflexes.
Plan: After evaluating and assessing the damage, plan the line of treatment. The treatment options include nonoperative, traction and operative methods.
• For stable fracture without neurological deficit Less than 30% anterior wedge, lateral, central compression fracture of the vertebral body is considered as stable fracture. In these injuries, there is no fracture of the posterior cortex of the vertebral body, and there is no disruption of the neural arch Treatment:
This is essentially conservative and consists of bed rest, NSAIDs and external spine supports like brace, corsets, etc. If the vertebral body compression is less than 30 percent, only corset is used; and if the compression is more than 30 percent but less than 50 %, a plaster jacket along with a corset is preferred.
• For stable fracture with neural deficit: First determined whether the neurological deficit is complete (loss of motor power, sensory loss and absent reflexes) or incomplete (only cord or only spinal nerve roots). If neurological damage is incomplete, IV steroids are given for 4 days.
Anterior decompression and anterior interbody fusion is done in the first stage, followed by posterior segmental spinal stabilization by either pedicle screws, Hart shill rectangle frame, Luque instrumentation, etc. can be done one week later. Laminectomy has fewer roles as it makes the spine less stable.
• Unstable fracture without neurological deficit: This is best treated by early open reduction, internal fixation and fusion is done preferably within 1224 hours. It is done with spinal cord monitoring. Internal fixation is either by VSP plates, Hart shill frame, Harrington instrumentation, titanium cages, etc
• Unstable fracture with neurological deficit: Systemic Decadron 4-6 mg/every 6 hours IV for 3 days is given. Early open reduction and internal fixation and fusion are done in incomplete neurological deficit cases. This is also desirable in complete neurological deficit to permit early-uninhibited rehabilitation. Segmental spinal stabilization with Luque or Hart shill frame is recommended.