Lumbosacral Spine Acute Bony Injuries Clinical Presentation
- Author: Federico C Vinas, MD; Chief Editor: Sherwin SW Ho, MD more...
In the assessment of an injured athlete, the history should include a description of the trauma and an exact description of the pain and any exacerbating factors. A past history of any spinal problem should always be obtained. Patients with lumbosacral fractures present with severe pain, deformity, and neurologic deficits related to compression of neural structures.
In healthy athletes, a significant traumatic event is required to produce a fracture of the lumbar spine, whereas in patients with caused by metabolic or endocrine imbalance, a relatively minor trauma can produce a pathologic fracture.
Any neurologic change at the time of the event, such as weakness, paresthesias, or radicular pain, should be documented. For example, lumbar fractures may cause solitary or multiple radiculopathies. Massive disc herniations, fracture-dislocations, and burst fractures can cause a cauda equina syndrome with variable paraparesis, asymmetrical saddle anesthesia, radiating pain, and sphincter disturbances. Complete damage of the sacral cord and nerve roots is manifested as no motor function or sensation below L1.
- The most useful classification of lumbar spine fractures is Denis's 3-column spine stability classification.[34, 35] According to this model, the spine consists of 3 columns.
- The anterior column is represented by the anterior half of the vertebral body, the anterior half of the annulus fibrosus, and the anterior longitudinal ligament.
- The middle column consists of the posterior half of the vertebral body, the posterior half of the annulus fibrosus, and the posterior longitudinal ligament.
- The posterior column is represented by the supraspinous and infraspinous ligaments, ligamentum flavum, articular processes, joint capsules, spinous processes, and the laminae.
- Instability occurs when 2 or more columns are injured. Because contiguous columns are commonly affected by the same injury, instability is heavily dependent on middle column failure.
- Magerl and colleagues proposed a classification scheme with 3 morphologic injury patterns, types A, B, and C, which result from 3 basic forces, compression, distraction, and rotation, respectively. These categories have been applied to all levels of the spine, and subcategories and subdivisions have been described based on the mechanism and severity of the fractures.
Mechanism of injury and relative force sustained
- A detailed history must be obtained, if possible, to ascertain the mechanism of injury and the relative force sustained.
- Individuals who fall often receive hyperflexion or compression injuries, such as spinous process fractures, burst fractures, or traumatic spondylolisthesis. These injuries are commonly associated with pelvic and lower-extremity fractures.
- Automobile racers who were using seat belts during motor vehicle accidents often receive compression or distraction injuries to the spine, which are frequently associated with cervical spine injuries. In these patients, burst fractures and fractures dislocations are relatively common.
- Head injuries and extremity fractures commonly accompany vertebral fractures.
- Abdominal or urologic trauma can occur frequently in patients with lumbar fractures.
- The possible presence of concurrent direct injuries to adjacent intracavitary soft-tissue structures, such as renal, spleen, or liver lacerations, must be considered. In general, the more caudal the vertebral injury, the greater the biomechanical forces that are sustained and the greater the propensity for injuries to the pelvis and sacrum.
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The initial management of patients with a lumbar spine injury begins in the field. Any patient who may have a spinal injury is placed on a board in a neutral supine position and immobilized in a neck collar for expeditious transportation to a trauma center. In the emergency department, all patients should be treated as having a spinal injury until this condition is excluded. Fractures of the thoracolumbar junction can produce a mixture of cord and root syndromes caused by lesions of the conus medullaris and lumbar nerve roots, whereas lower lumbar fractures may cause solitary or multiple root deficits.
The Advanced Trauma Life Support (ACLS) guidelines of the American College of Surgeons should be followed. Stabilization of the patient's airway and hemodynamic status in order to secure adequate oxygenation and tissue perfusion should precede any treatment. A Foley catheter should be inserted. In patients with neurologic deficit, immediate peritoneal lavage is often advocated to rule out intra-abdominal injuries. Once the patient has been resuscitated, plain films of the cervical, thoracic, and lumbosacral spine should be taken.
- The physical examination of the athlete with an acute spinal fracture is usually limited by the patient's severe pain.
- During the spinal examination, the overlying skin should be inspected for abrasions or contusions.
- Attention should be directed to general deviations from the normal spine curves (ie, thoracic kyphosis, lumbar lordosis).
- Muscle spasm from pain frequently flattens the spine, whereas spinal fractures may cause a kyphotic or scoliotic deformity.
- The spine should be palpated for areas of tenderness or fractured, displaced spinous processes.
- Sometimes, the initial examination of these patients can be difficult because of multiple trauma, spinal shock, or sedation. Any neurologic deficit should be documented according to the American Spinal Injury Association (ASIA) Motor Index.
- A motor examination should be performed on all conscious patients. Muscle strength and weakness are graded based on a strength scale from 0 to 5, with 5 considered normal and 0 considered paralysis. Muscle strength grading is as follows:
- Grade 0 – No contraction
- Grade 1 – Flicker of movement
- Grace 2 – Can move when gravity is eliminated
- Grade 3 – Can elevate against gravity
- Grade 4 – Can move against resistance (-4 for slight resistance, 4 for moderate resistance, and +4 for strong resistance)
- Grade 5 – Normal strength
- A detailed neurologic evaluation should include detection of a sensory level, posterior column function, and normal and abnormal reflexes and an examination of rectal tone and perianal sensation. The cutaneous abdominal reflex, bulbocavernosus, anal wink, and the presence of a Babinski sign should also be noted and documented. The Beevor sign consists of a cephalic movement of the umbilicus when the patient is asked to elevate the head in the supine position. This is due to paralysis of the lower abdominal muscles.
- A rectal examination to check for rectal tone and voluntary sphincter function should always be included.
- Repeated neurologic examinations should be performed and documented at regular intervals to serve as references for improvement or deterioration in the patient's neurologic status over time.
- In patients with a complete spinal injury (paraplegia or quadriplegia), spinal shock can last 24-48 hours, suppressing all reflex activity below the level of the lesion. The return of reflex activity (bulbocavernosus and anal reflexes) in the absence of any return of sensation or motor function is generally a poor prognostic indicator. Some return of motor or sensory function below the level of the lesion encourages the possibility of some return of useful neurologic function.
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The forces responsible for spinal fractures are compression, flexion, extension, rotation, shear, distraction, or a combination of these mechanisms. In athletes, the most common acute fractures are compression fractures (see the image below) or vertebral endplate fractures caused by sudden axial loading, transverse process avulsion by the origin of the psoas muscle, spinous process avulsions, and acute fracture of the pars interarticularis from hyperextension.
See the list below:
Vertebral body compression is more common in athletes with decreased bone density from a cause such as exercise-induced amenorrhea. In adolescents, endplate fractures (Schmorl node) or apophyseal avulsion fractures are relatively common. All these injuries are generally stable and heal with immobilization and nonsurgical management.
Spinous process fractures may occur as a result of direct trauma to the posterior spine or as a result of forcible flexion and rotation. These injuries are not usually associated with neurologic deficits. Violent muscular contraction or direct trauma can cause fractures of the transverse processes. For example, a football helmet blow to the back can cause fractures of both spinal and transverse processes. Despite their relatively innocuous appearance, these fractures can cause significant bleeding into the retroperitoneal space, resulting in acute anemia, or ileus.
Sports that cause frequent hyperextension of the lumbar spine induce stress on the pars interarticularis. A defect in the pars interarticularis or spondylolysis is common in competitors in sports that require repetitive or prolonged hyperextension of the spine, such as tennis (the serve), volleyball (the spike), and track (the high jump). Athletes with back pain and spondylolysis fall into 2 main groups, (1) those with acute or subacute lesions related to a precipitating episode of hyperextension or trauma and (2) those with well-established, chronic spondylolysis. Although each of the following lesions in isolation can appear benign, the spinal column must be evaluated further to rule out additional injury.
- Female gymnasts have an incidence of pars defects 4 times greater than the general population. This is presumably the result of gymnastics maneuvers that load the spine in hyperextension (eg, dismounts, back walkovers, aerials).
- Other athletes at higher risk for pars spondylolysis include ballet dancers, divers, and football linemen.
- Thoracolumbar fractures have been estimated to occur in 14% of snowmobile injuries, 5% of alpine skiing injuries, and 8% of freestyle skiing injuries.
- Direct trauma from hockey- or football-related injuries can also cause a fracture of an articular process.
Acute traumatic spondylolisthesis is usually associated with major trauma and is usually caused by extreme hyperextension. Although patients with a new fracture of the pars interarticularis may have a slip present at the time of the injury, a slip can occur months to years later as the disc degenerates under shear loads that it cannot sustain.
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