General Principles
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With an increased number of adults and adolescents participating in fitness programs and competitive sports, there has been an increase in thoracic and lumbar spinal problems.
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Most injuries are soft tissue injuries, and appropriate training and avoidance of aggravating activities may allow participation while the pain resolves.
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Treatment of an athlete can be complicated by his or her competitiveness and the fact that the athlete will be returning to the activity that precipitated the injury.
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The primary treatment objective is the protection and preservation of the nervous system.
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Spine injuries occur with a reported incidence of 7%–27% among sports-related injuries.
Anatomy
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The spine is a mechanical structure consisting of bones, joints, ligaments, and muscles surrounding and distributing neural elements.
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The thoracic spine is more stable than the lumbar and cervical spine and is less mobile because of the thoracic cage.
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The spinal column is composed of 33 vertebrae divided into five sections: cervical (7), thoracic (12), lumbar (5), sacral (5), and coccygeal (4) ( Fig. 53.1 ).
Osseous
Vertebral body: Large, strong, anterior weight-bearing structure (see Fig. 53.1 )
Posterior vertebral arch: Semicircular-shaped structure surrounding the central canal, above and below the vertebral foramen through which the roots pass; composed of pedicles, which project dorsally off the body, one on each side, and the lamina, which connects the pedicles; from the pedicles and lamina, project the transverse process ; from the lamina, project the spinous process ; these are locations for muscular attachments. Each lamina articulates with the lamina above and the lamina below through facet joints . These synovial-lined facet joints are formed by a superior articular process from the lamina below and an inferior articular process from the lamina above and are surrounded by a facet capsule or ligament (see Fig. 53.1 ).
Pars interarticularis: Literally, the “part between the joints” or the area between these facet joints; relevant because it is the weak link anatomically and is susceptible to injury and stress fracture
Sacrum: Coalesced lower segments of the spine that articulate with the pelvis
Costovertebral joints: Area of articulation of the thoracic vertebrae with its rib
Disc: Major ligament connecting each vertebral body; composed of two types of tissue: annulus fibrosus (outer layer of fibers that functions to hold the nucleus pulposus and restrains the vertebral bodies) and nucleus pulposus (gelatinous structure located in the annulus)—both are responsible for load bearing
Ligaments
Anterior longitudinal ligament: Strong bond of fibrous tissue that runs the entire length of the spine along the anterior vertebral bodies (see Fig. 53.1 )
Posterior longitudinal ligament: Weaker than the anterior ligament; runs along the posterior surface of the vertebral bodies
Ligamentum flavum: Very strong ligament attaching the lamina above to the lamina below
Facet capsule: Connects each superior articulating process with its corresponding inferior articulating process
Interspinous ligament: Connects each spinous process to the one below
Supraspinous ligament: Runs along the dorsal surface of the tips of the spinous processes
Costotransverse ligaments: Thoracic area
Muscles and Fascia
Thoracolumbar fascia: Investing tissue that separates the muscular compartments and fuses with the aponeuroses of several muscles (see Fig. 53.1 )
Anterior groups of muscles: Anterior to the transverse processes; include psoas, intertransversalis, quadratus, and levator costae
Posterior groups of muscles: Posterior to the transverse process; include superficial muscles, erector spinae (semispinalis, longissimus, and iliocostalis), deep muscles, multifidus, rotares, and interspinalis
Accessory group of muscles: Includes abdominal muscles, latissimus dorsi, rhomboids, and gluteus maximus
Neural Elements
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Neural elements of the spine include the spinal cord from occiput to about L1, the conus medullaris or lower portion of the cord thickened by the mass required to innervate the lower extremities located from T11 to L1, and the cauda equina from L1 to the sacrum; the nerve roots exit at each level on both sides of the canal via the vertebral foramina (see Fig. 53.1 ).
Vascular Elements
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Vascular elements of the spine include a complex system of intradural and extradural arteries and veins that supply the neural elements.
Biomechanics
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The spinal column has five principal functions:
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Support of the head
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Support of the abdominal contents and pelvic girdle
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Point of attachment for the thoracic cage and muscles
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Protection of the spinal cord and the neural elements within while allowing motion
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The biomechanical transfer of the weight and bending movements of the head and trunk to the pelvis
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Understanding several basic concepts of biomechanics helps us understand how specific activities can exacerbate symptoms in certain syndromes:
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In the spine, flexion of the lumbar spine increases the size of the intervertebral canal and the intervertebral foramina.
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Extension decreases the size of the intervertebral canal and the intervertebral foramina.
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Flexion increases dural sac and nerve root tension.
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Extension decreases dural sac and nerve root tension.
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Front flexion, axial loading, and an upright posture increase intradiscal pressure: pressure is greater while sitting, less while standing, and least while lying down.
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With flexion, the annulus bulges anteriorly.
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With extension, the annulus bulges posteriorly.
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Nuclear shift in an injured disc is poorly documented, but the disc probably shifts in the direction of the annular bulge.
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Rotation and torsion produce annular tears and disc herniations.
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History and Physical Examination
History
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Information obtained during history taking and physical examination is critical. The following questions are particularly relevant.
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When and how did your symptoms start? Mechanism of injury can help locate the damage. Onset can be telling because a gradual onset can be more related to a stress injury and a rapid severe onset may indicate a more acute injury.
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What is the location of the pain? Neurologic involvement is likely when a patient perceives more pain in the leg than in the back. The percentage of back to leg pain is relevant. Associated neurologic symptoms such as numbness, dysesthesia, weakness, or spasticity are important to note. There are multiple nociceptive sources in the spine.
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When does it hurt? Night pain may be more ominous and associated with tumors. Pain with motion and relieved by rest implies mechanical pain. Constant pain unaffected by rest may indicate an inflammatory component.
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What makes it worse? Discogenic pain is usually worse with flexion or prolonged sitting and increases with a Valsalva maneuver (cough or strain with defecation). Pain from a spondylolysis is worse than that with hyperextension. Pain from spinal stenosis (pseudoclaudication) is worse with ambulation or prolonged standing. Sacroiliac (SI) joint dysfunction can be worse with hyperextension.
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What makes it better? Discogenic pain can be improved by lying down with knees and hips flexed (opens foramina and unloads disc). Spinal stenosis symptoms can improve by bending forward (as in walking over a grocery cart) or by sitting.
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How do you train? This may reveal a voluntary restriction that helps with a diagnosis or reveals a training error compatible with a specific syndrome.
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Do you have any of these factors? Bowel, bladder, or sexual dysfunction may indicate significant neurologic involvement of the cord, conus, or cauda equina. Weight loss, anorexia, night pain, and pain at rest may suggest neoplasia. Fever may indicate infection. A visceral type of pain with referral may indicate kidney, prostate, bowel, or vascular pathology.
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Physical Examination
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Should address inspection, palpation, and percussion and identify
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Exact location of tenderness, dysesthesias, or numbness
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Maneuvers that reproduce the pain
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Presence of neural tension signs
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Deficits in range of motion (ROM)
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Any neurologic deficit
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Inspection of posture and stance: Patients in a sitting position may tend to tripod or lean back to unload the spine. When standing, a list to one side may suggest nerve root compression. The appearance of a flat back with a vertical sacrum may be seen in advanced spondylolisthesis. Scoliosis may be detected in a standing position.
Inspection of gait: Myelopathic patients may walk with spasticity. A forward flexed posture can be seen in stenosis. Patients with discitis may have a rigid short-stride gait.
Inspection of ROM: May be limited by painful conditions; extension may be limited in stress fractures and facet syndromes. Discogenic pain may limit flexion.
Palpation: May detect muscle spasm, deformity with a palpable mass, scoliosis, spondylolisthesis, or a gibbus deformity; tenderness may present at the sciatic notch.
Percussion: May elicit tenderness in trauma or infection and costovertebral angle tenderness may imply a kidney problem
Neurologic: Most critical portion of the examination ( Table 53.1 and Fig. 53.2 ); upper motor neuron findings of spasticity, weakness, numbness, hyper-reflexia, and clonus may indicate spinal cord pathology; lower motor neuron findings of flaccid muscles, weakness, numbness, hyporeflexia may indicate cauda equina or root injury. Sensory levels on the trunk will help determine the level of spinal cord injury, if present. A rectal and cremasteric reflex examination is recommended with any spinal cord injury.
TABLE 53.1
Root
Strength
Sensation, Dermatomal Distribution
Reflex
L1–L2
Iliopsoas
Inguinal area and upper two-thirds of anterior thigh
L3
Quadriceps
Oblique band of distal third of anterior thigh immediately above patella
L4
Tibialis anterior and quadriceps
Medial side of lower leg and foot
Patellar tendon
L5
Extensor hallucis longus, and tibialis anterior
Anterior aspect of lower leg and dorsum of foot
Not reliable (posterior tibialis reflex present in only 40%–50% of population)
S1
Peroneus longus and brevis gastrocnemius
Lateral aspect of lower leg and lateral foot
Achilles tendon reflex
Special Tests
Pain From Neural Source
Straight leg raise (SLR) test: Tension test that indicates nerve irritation in the sciatic nerve if positive with radicular pain at <60–70 degrees of leg elevation ( Fig. 53.3 )
SLR test with foot dorsiflexion (Lasègue’s test): Tension test suggesting sciatic nerve irritation if painful
SLR test while sitting: Positive when extending the knee while patient is sitting causes radicular pain; patient may lean back to gain relief. A positive and a negative SLR test while sitting can be inconsistent and suggest other etiologies.
Crossed SLR test: Positive test may be pathognomonic for a herniated disc. With the patient sitting, the examiner lifts the unaffected leg; in the presence of a herniated disc, this may produce pain in the affected leg.
Femoral stretch test: In a side-lying position with knee flexed 90 degrees, the hip is extended, stretching the femoral nerve. Pain on the anterior thigh suggests femoral nerve or upper lumbar root irritation.
Pain From Structural Source
Jackson’s one-legged standing hyperextension test: If painful, it suggests a stress fracture (spondylolysis), a facet syndrome, or SI joint dysfunction.
Flexion, abduction, and external rotation of hip (FABER) or Patrick’s test: Can suggest hip joint or SI joint dysfunction
Supine-to-long sitting test: Examiner tests leg length at the medial malleoli with the patient first supine then sitting with both legs extended at the knees. A change in relative leg length may indicate SI joint dysfunction.
Radiographic and Ancillary Testing
Plain radiographs: May be unnecessary in the acute phase in a nonathletic clinic setting, but in high-velocity and collision sports, early radiographic evaluation may be needed. Plain radiographs may reveal an acute fracture or spondylolysis that may alter the treatment. Plain radiographs may also reveal spondylolisthesis, degenerative changes, signs of infection in discitis (endplate irregularities), or congenital anomalies. Anteroposterior (AP) and lateral radiographs of the lumbar spine may be augmented by right and left obliques if a spondylolysis is suspected.
Bone scan: May be used to reveal lesions that are not yet visible on plain radiographs (e.g., stress fractures in the pars interarticularis); because a positive bone scan indicates increased metabolic activity, this scan may reveal bone tumors or infection as well as occult fractures. It may take up to 5 days after the onset of symptoms for a bone scan to be positive.
Computed tomography (CT) scan: To evaluate osseous lesions and to help stage stress reactions
Magnetic resonance imaging (MRI): To help detect discogenic lesions such as degenerative disease with desiccation, disc herniations, spinal cord lesions, fractures, stress reactions, and compressive lesions
Myelography and CT myelography: May also be used to show compressive lesions
Electromyography (EMG) and nerve conduction velocity (NVC): May help in localizing the location of a nerve compression lesion; it may take up to 3 weeks before denervation changes occur such that they are revealed on an EMG.
Laboratory studies: Can be useful in diagnosing discitis, inflammatory spondylitis, or neoplasia, but these studies are rarely needed