Spinal injuries in athletes

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What sports are associated with the highest risk of head and neck injuries?

The organized sports with the highest risk of head and neck injuries are football, gymnastics, wrestling, and ice hockey. Football is associated with the highest risk of such injuries. Head and neck injuries also occur in a variety of nonorganized sports activities, including diving, skiing, surfing, and trampoline use.

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What types of cervical injuries are considered in the differential diagnosis of an injured athlete?

Sports-related cervical injuries can involve the muscles, tendons, ligaments, intervertebral discs, osseous structures, and neural elements. Common athletic cervical injuries include muscular strains, intervertebral disc injuries, major and minor cervical spine fractures, stinger or burner injuries, and cervical cord neuropraxia. In addition, preexisting cervical conditions may predispose an athlete to neurologic injury and be discovered during subsequent evaluation. These include congenital cervical stenosis, Klippel-Feil syndrome, and os odontoideum.

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When performing an on-field assessment of an athlete’s cervical spine, how does the presence of neck pain versus extremity symptoms help guide differential diagnosis?

See Fig. 60.1 .

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What is the most common mechanism responsible for catastrophic sports-related cervical spine injuries?

Catastrophic cervical spine injuries result in injury to the spinal cord that causes temporary or permanent neurologic injury. The primary mechanism responsible for catastrophic sports-related cervical spine injuries is axial loading resulting from head contact while the neck is in a slightly flexed position. When the cervical spine is in lordotic alignment, it is capable of absorbing applied loads. However, when the neck is flexed, force applied directly along the axis of the spine results in axial loading of the cervical spine.

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What is the most common sports-related injury of the cervical spine?

The most common sports-related injury involving the cervical spine is a soft tissue injury involving muscles, tendons, or ligaments in the cervical region. Despite the frequency of these injuries, careful evaluation is warranted to rule out a more serious injury. The athlete may return to sports if neck pain is resolved, neck strength is normal, full functional cervical range of motion is present without pain, and cervical radiographs are normal.

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Explain what is meant by a “hidden flexion injury” of the cervical spine?

This term refers to a purely ligamentous injury associated with three-column disruption of the spine, in the absence of osseous injury. Such injuries may be missed on plain radiographs. Persistent posterior cervical tenderness following an acute injury should raise concern about the possibility of this injury pattern. The lateral cervical radiograph should be carefully evaluated for a subtle increase in the distance between adjacent spinous processes. Cervical magnetic resonance imaging (MRI) is useful to evaluate posterior cervical ligamentous disruption. Physician-supervised flexion-extension lateral radiographs are considered only for alert, cooperative, and neurologically intact patients, and are not advised or considered useful in the immediate postinjury period. Criteria for defining instability between adjacent motion segments in the subaxial cervical region are 11° or greater angulation or 3.5 mm or greater translation of one vertebra relative to an adjacent vertebra.

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Describe the clinical presentation of a traumatic cervical disc herniation?

The clinical presentation of a traumatic cervical disc herniation is variable. Patients may present with isolated neck pain, radiculopathy, or an anterior cord syndrome with paralysis of the upper and lower extremities. In contrast to adults in whom cervical disc herniations occur most commonly at C5–C6 and C6–C7, immature athletes most commonly develop disc herniations at C3–C4 and C4–C5. Disc injury is associated with axial loading and hyperflexion during activities such as wrestling, diving, and football.

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What is spear tackler’s spine?

Spearing refers to contact the crown of the head while the neck is maintained in a flexed posture. In this posture, the normal cervical lordosis is no longer present, and the cervical spine is predisposed to injury. Injuries due to this mechanism have been described in football, diving, and hockey. Spear tackler’s spine was defined by analysis of injured football players and is considered to be a contraindication to participation in contact sports. Criteria for diagnosis of spear tackler’s spine include:

• Developmental narrowing of the cervical spinal canal

• Persistent straightening or reversal of cervical lordosis on erect lateral cervical radiographs

• Posttraumatic radiographic changes on cervical radiographs

• History of use of spear-tackling techniques during athletics

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What is a stinger or burner?

A stinger or burner (burner syndrome) is a peripheral nerve injury involving individual cervical nerve roots or a portion of the brachial plexus. It is associated with unilateral burning arm pain or paresthesias and may be accompanied by weakness, most often in the muscle groups supplied by the C5 and C6 nerve roots (deltoid, biceps, supraspinatus, infraspinatus) on the affected side. Although pain may resolve spontaneously in minutes, it is not uncommon to have trace abnormal neurologic findings for several months. Bilateral symptoms suggest a different etiology, such as a neuropraxic injury of the spinal cord. Injury mechanisms responsible for stingers include: (1) head contact leading to hyperextension, compression, and rotation toward the involved arm, thereby closing the neural foramen and causing a nerve root contusion (essentially a replication of the Spurling maneuver); and (2) head abduction and lateral neck flexion combined with shoulder depression on the affected side, resulting in brachial plexus stretch. Three grades of injury have been described:

• Grade 1: neuropraxia. This is the most common injury type. All nerve structures remain intact. Complete resolution of symptoms typically occurs in minutes, but may take as long as 6 weeks.

• Grade 2: axonotmesis. Axonal disruption and Wallerian degeneration occur distal to the injury site. Recovery is complete, but may take months. An intact epineurium allows axonal regrowth at a rate of approximately 1 mm/day.

• Grade 3: neurotmesis. There is complete disruption of axons, endoneurium, perineurium, and epineurium. The prognosis varies, and complete loss of function is common.

Most stingers resolve within minutes. For an athlete’s first episode, with only brief transitory symptoms, treatment is conservative and no special testing is required. Neck and shoulder muscle strengthening programs can have a positive effect on recovery and help reduce recurrences. If the symptoms have not resolved by 3 weeks, electromyography (EMG) may be considered to define the specific pattern of nerve root involvement but is not useful to guide return to play as abnormal EMG findings lag behind motor recovery. An athlete should not return to play until there is pain-free and unrestricted neck and shoulder range of motion; resolution of paresthesias; normal motor strength; and provocative tests are negative, including the Spurling test, brachial plexus stretch test, and axial compression test.

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What is cervical cord neuropraxia?

Cervical cord neuropraxia is a temporary neurologic episode following cervical trauma and is characterized by the presence of sensory symptoms with or without motor changes involving at least two extremities in the absence of cervical instability. The most commonly described mechanism of injury is axial compression with a component of either hyperflexion or hyperextension. Neurologic findings are classified according to severity as plegia (complete loss of motor function), paresis (motor weakness), or paresthesia (sensory symptoms only) and graded by duration as grade I (<15 minutes), grade II (15 minutes–24 hours), and grade III (>24 hours). The anatomic distribution of neurologic symptoms is variable and may involve all four extremities, both arms, both legs, or an ipsilateral arm and leg. Neurologic symptoms are transient and typically last between 15 minutes and 36 hours. Neck pain is often absent.

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