The Immature Spine and Athletic Injuries

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CHAPTER 29 The Immature Spine and Athletic Injuries

Robert Eilert, MD

Most spine injuries in athletically active children and adolescents are chronic, resulting from repetitive demand on the immature spine during participation in sports. The most serious injuries are acute as a result of direct trauma. The age at which a child can be considered an athlete varies and may be 3 years old when a child puts on skis or 10 years old when he or she begins to ride bulls (Fig. 29–1). Several sports, such as skiing, football, and horseback riding, involve increased risk of acute traumatic events, making spine fracture a significant concern when considering an adolescent athlete. This chapter discusses the initial evaluation and on-field management of spine fractures; the complete treatment of spine fractures is covered elsewhere.

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FIGURE 29–1 This 10-year-old boy is following the traditions of ranch life in Colorado where rodeo is a part of life. He won his first big belt buckle in competition at 8 years old.

According to surveys of patients seen in sports medicine specialty clinics, the most common cause of back pain in adolescent athletes is stress fracture, or spondylolysis. Spine hyperextension and repeated twisting contribute to the high rate of spondylolysis seen in sports such as gymnastics, football, and weightlifting. The rate of spondylolysis in gymnasts is 20% compared with 5% to 6% in the general population.1

Less aggressive sports such as golf can also cause adolescent back pain and spine injury. The golf swing places significant torque on the spine and surrounding muscles and can produce strains and sprains, which are minor injuries that interfere with performance. In all sports, appropriate strength training, routine stretching, and good technique are imperative for young athletes to avoid injury and to continue participation in sports throughout their lifetime.

The most effective technique in screening for serious disease is a good patient history, and diagnosing spine injury is no exception. Although helpful, a radiograph is seldom definitive in diagnosing the cause of back pain. Radiography is imperative for diagnosis of an acute fracture, but back pain without a specific injury is usually treated on the basis of a careful history and a thorough physical examination.

Understanding the requirements of the particular sport and gaining knowledge of the training schedule of the athlete are important when performing the patient history. For example, a gymnast with no history of sudden trauma who practices 3 hours daily has a chronic stress that may account for her back pain. A young gymnast’s developing spine, given insufficient recovery time, is highly susceptible to repetitive trauma.

Return to sport is a major goal for an athlete, and the physician needs to be aware of the demands of the specific sport to determine when return to participation is reasonable. The physician should take heed of a young athlete who is reluctant to return to sport after an injury. Family dynamics often influence when a child is willing to resume activity.

Physical activity is the normal function of the musculoskeletal system. The American Academy of Orthopaedic Surgeons (AAOS) has encouraged physical activity as health promoting for all ages in its “Get Up, Get Out, Get Moving” program. The keys to maintaining a healthy spine are good nutrition and proper exercise. Good nutrition includes avoiding obesity and not smoking. Exercise programs should include strengthening for power and endurance and stretching to improve joint range of motion and muscle length.

Principles of Diagnosis

The initial treatment of low back pain usually begins without a specific diagnosis. A nonspecific diagnosis is satisfactory as long as the patient’s condition improves. In contrast, the narrow area in which surgery offers reliable benefit to the patient requires a carefully determined, specific diagnosis.

History

A good patient history depends on effective patient-physician communication. When a patient presents with low back pain, the history is important to rule out serious diagnoses rather than leading to a definitive diagnosis. The physician brings knowledge of possible causes and treatments to the interview and assembles a differential diagnosis. The patient wants to tell his or her story and brings knowledge of timelines and anecdotal details.

The term interview implies an interaction with the patient as opposed to the traditional notion of extracting information from the patient. When allowed to tell his or her story, an adult patient takes an average of 90 seconds.2 Adolescents tend to be more taciturn and talk less than the average adult. The average physician cuts off the patient with a question after 18 seconds because he or she has formed a differential diagnosis. Such interruption stops the flow of information, and often the patient is never permitted to relate pertinent facts.

The use of a visual pain scale facilitates consistent documentation. The patient’s assessment of the intensity of the pain using a visual scale (Fig. 29–2) often stimulates a description of the circumstances that exacerbate or alleviate that pain. When making the differential diagnosis, the physician can classify the clinical syndrome into one of three categories: (1) nonmechanical back or leg pain (or both), (2) mechanical back or leg pain (or both), and (3) sciatica.

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FIGURE 29–2 Bieri faces. Drawings are neutral in terms of gender and ethnicity. The patient indicates a number that corresponds to his or her pain between 0 and 10.

Warning signs for possible cancer include a history of cancer or constitutional symptoms such as fever or weight loss. Risk factors for infection include a history of recent bacterial infection, intravenous drug use, or an immunocompromised state. Patients with a spine cancer or spine infection often have pain that is not diminished by rest. Warning signs of possible spine fracture are major trauma (e.g., motor vehicle accident, blunt trauma, fall from a height), prolonged corticosteroid use, and osteoporosis. Symptoms suggestive of cauda equina syndrome, which requires urgent surgical consultation, include saddle anesthesia (found in 75% of patients); recent onset of bladder or bowel dysfunction (with urinary retention the most common symptom); and severe or progressive weakness of the lower extremities,3 especially involving both lower extremities.

There are several findings to note when ascertaining psychosocial contributions to nonorganic back pain, as follows4:

1 Superficial nonanatomic tenderness. Lightly pinching or rolling the skin should not affect the deep structures, which might cause true pain.
2 Patient’s response to positive stimulation such as axial loading. Lightly placing one’s hand on top of the head should not significantly increase pressure in the low back.
3 Distraction. One should look for a significant difference in straight-leg raising ability in the seated versus the supine position.
4 Overreaction. An overly loquacious patient or behavior disproportionate to the stimulus should be noted.
5 Disturbances in sensation or distribution of pain or weakness that do not follow anatomic patterns.

Symptoms and signs that suggest back pain from nonmechanical causes, such as subclinical pyelonephritis, kidney stones, or dissecting aneurysm, should also be considered.

Genetics

The “wild card” in the etiology of sciatic pain is genetics. Ala-Kokko5 noted that scientific studies have identified specific versions of the genes encoding collagen, aggrecan, vitamin D receptor, and matrix metalloproteinase-3 that have significant associations with lumbar disc disease. Many other genes may also play a role in disc disease.6–8

Physical Examination

The physical examination should take into consideration the three reasons for orthopaedic consultation: pain, deformity, and dysfunction. Although there is poor correlation between physical findings, symptoms, and treatment outcome, an examination of the patient’s back is necessary. The purpose of physical examination is to confirm the impression gained from the history, if possible, and to look for surprises. Many obvious anatomic abnormalities can be visualized only when the patient’s back is bare. The physical examination usually helps to exclude a serious disease rather than identify one. The “three S’s” of an abnormal spine examination are apparent to observation: spasm, scoliosis, and spondylolisthesis.

Watching the patient move in flexion, extension, and rotation gives a visible assessment of pain. How a patient moves is as important to note as the range of motion. Whether the patient can bend to the knees, below the knees, or to the toes provides a rough measure of flexibility. Observing spinal rotation allows one to evaluate the facet joints.

After checking range of motion and palpating for tenderness and muscle spasm, the physician should observe the rotational symmetry of the spine using the Adams forward-bend test and noting whether the pelvis is level. It is worthwhile to observe the effect of compression of the pelvis while the patient is lying on his or her back because this is a nonspecific test for sacroiliac joint disorders.

Observing standing posture in the coronal and sagittal planes is important to document evidence of deformity. Special tests such as one-leg standing (the stork test) and compression tests for the neck (Spurling test) are indicated when one suspects spondylolysis or compression neuropathy. Anisomelia can be diagnosed by measuring limb lengths from the anterior superior iliac spine to the medial malleolus.

The neurologic examination requires close attention to detail and begins by having the patient heel walk and toe walk. Both functions demand strength, coordination, and cooperation one would expect from an athletic child. Testing deep tendon reflexes is important, especially if they are asymmetrical; testing the abdominal reflexes is essential to detecting hydromyelia.

The straight-leg raise test or Lasègue sign is a test for nerve root irritation or inflammation. A positive response is the reproduction of radicular pain. Pain on the opposite side or a positive “cross straight-leg raise test” is significant for diagnosis of a herniated disc. The straight-leg raise test can simultaneously provide evidence of sciatica and hamstring contracture.

Imaging

Modern imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI) permit accurate visualization of anatomic defects in the spine. Although both techniques are powerful diagnostic tools, the defects revealed by CT or MRI are not always causative with regard to the patient’s pain. The literature is replete with cases in which anatomic defects are present on MRI or CT in completely asymptomatic patients.

The Cochrane group performed a meta-analysis of the literature and concluded that there is no correlation between radiographic changes and back pain.9 Contrary to that opinion, researchers in Tokyo reported a study in which they correlated preparticipation spinal radiographs with the incidence of back pain and disability among young football players.10 They followed 171 high school and 742 college football players over a 1-year period. High school players with spondylolysis had a higher incidence of low back pain (79.8%) than players with no radiographic abnormality (37.1%). College players with spondylolysis, disc space narrowing, and spinal instability had a higher incidence of low back pain (80.5%, 59.8%, and 53.5%) than players with normal radiographs (32.1%). College players with spondylolysis had a higher incidence of low back pain than players with disc space narrowing and spinal instability.

How can this incongruence of findings be explained? It is believed that asymptomatic abnormalities in the general population, particularly abnormalities seen with aging, may become symptomatic with vigorous physical activity. Abnormal spine radiographs in a young athlete should be considered a risk factor for injury.

Magnetic Resonance Imaging of the Spine

MRI technology takes advantage of the high hydrogen content of the molecules that make up biologic tissues. Hydrogen atoms have a specific “spin” property associated with them, and the “spin” state can be altered in the presence of a strong magnetic field. Alterations in the “spin” properties of hydrogen atoms in biologic tissues can be detected by MRI technology, and highly sensitive visual images are produced.

Although MRI is a very sensitive and accurate assessment of spinal anatomy, it cannot distinguish between painful and painless structures in the spine. A patient may have severe back pain and MRI may reveal no abnormalities, or the converse may be true. It can be difficult for the physician to correlate MRI findings with the patient’s signs and symptoms to make a clinical diagnosis. Typically, it is unnecessary to obtain MRI at the onset of spine-related pain because most cases of back and neck pain resolve within 2 to 12 weeks with proper conservative treatment. MRI is indicated when more aggressive treatments (e.g., injections or surgery) are contemplated.

Bone Scan or Bone Scintigraphy

Bone scan or bone scintigraphy is not as specific as MRI or CT but is very sensitive to changes in metabolic activity of bone. Increased metabolic activity is seen with inflammation, infection, and tissue proliferation owing to tumors such as osteoid osteoma. Bone scintigraphy uses a short-lived radioactive pharmaceutical agent to label specific tissues or structures and ultimately to visualize them via scintillation-mediated imaging. Gamma emissions from the radiopharmaceutical are detected by a gamma camera, converted to light photons, amplified with photomultiplier tubes, and digitized via computer to present a high-resolution (4 to 6 mm) two-dimensional image.

Single Photon Emission Computed Tomography

With single photon emission computed tomography (SPECT), gamma camera detectors rotate around the patient in small increments (usually 3- or 6-degree steps), and emission data are obtained from different plane angles. Computer algorithms break the image into pixels, each of which represents an approximately 6-mm area of the planar image. Pixel data are used to render clinically useful volumetric images. SPECT is arguably the best screening examination for significant spinal abnormality versus nonspecific back pain in children and the first examination that should be ordered. Auerbach11 showed that SPECT exceeded MRI or plain radiography in accurately defining spondylolysis in a series of 100 children with significant back pain.

Principles of Treatment and Rehabilitation

Acute Treatment

When pain onset is acute and severe, bed rest may be necessary for 2 or 3 days for initial pain control. A longer period of bed rest quickly becomes counterproductive. The key to recovery is modified activity within a minimal range to start, followed by gentle progression of activity. The sooner the athlete begins a level of tolerated activity, the quicker and more effective is the recovery. Research and experience have dispelled the notion that prolonged absolute rest is beneficial for treatment of back pain.12

Nonsteroidal anti-inflammatory drugs can be potent when given with muscle relaxants, but the duration of medication should be no longer than 10 days. Opioid administration is rarely necessary for more than a few days. Local anesthetic injections into the facet joints or into trigger points can be useful treatments and may help to diagnose disease related to the facet joint or fibromyalgia.

Passive physical therapy modalities such as ice, massage, or heat can be helpful in initial treatment, but the athlete needs to begin active rehabilitation and assume responsibility for his or her recovery. Strengthening should begin as soon as possible, and bracing should be minimized.

Bracing

Bracing is effective in some cases, if used intermittently and primarily as a tool for returning to activity. If used as a “crutch,” extended time in a brace produces atrophy and loss of motion. The Cochrane Collaboration reported a meta-analysis on the use of braces for low back pain in 2004.13 There was moderate evidence that lumbar supports are no more effective for primary prevention than other types of treatment or no intervention. The authors found no data promoting the effectiveness of lumbar supports for secondary prevention. This opinion is consistent with the generally held concept that passive treatment such as bracing should be limited to acute pain relief and that active rehabilitation is an early goal for return to participation in sports and prevention of future injury. Spinal manipulation can provide short-term improvement, but the evidence for longer term relief is inconclusive.14

Traction

Traction has historically been used to treat low back pain. Current thought remains disparate, however, regarding the therapeutic value of traction.15 Multiple reviewers have concluded that traction as a treatment for back pain is an outmoded technology that has fallen out of favor.

Rehabilitation

The rehabilitation program consists of stages—building a foundation of fundamentals and moving through increasingly difficult levels of activity. Physical rehabilitation should be designed to be sport specific and diagnosis specific. A gymnast with spondylolysis needs a program avoiding hyperextension while the bone is allowed to heal. As rehabilitation goals, he or she needs to stay active in the maneuvers that do not stress the back and to maintain general fitness.

Generally, rehabilitation begins with flexion and extension cycles to reduce joint stiffness and relax elastic structures. There should be minimal loading of the spine during this stage. Hip and knee range of motion exercises are added next to offload the spine, followed by specific muscle training. Focus is first placed on the anterior abdominal muscles and maintaining the spine in neutral position, followed by lateral muscle exercises for side support of quadratus lumborum and abdominal wall muscles; finally, an extensor muscle program is added. Repetitions and movement duration should be closely monitored by the therapist.

Core Stabilization

A core stabilization program is based on the principle of coordinated muscle contraction. This contraction is done from a neutral, pain-free position. Finding and maintaining a pain-free position is fundamental to reestablishing isometric muscle control. Flexibility training should not be approached until strength has been regained.

Flexibility

Exercise programs that load the spine throughout the range of motion have poorer outcomes. Greater mobility is associated with poorer outcomes as well. The range of motion of the spine has little predictability for future low back pain. Programs emphasizing trunk stabilization with a neutral spine have had the most success.16–18 These programs emphasize increasing the range of motion of the hips and knees.

Muscle Performance (Strength versus Endurance)

The term strength is defined as the maximum force a muscle can produce during a single exertion to create joint torque. The term endurance refers to the ability to maintain a force for a period of time. Muscle performance includes strength and endurance. The few studies available suggest that endurance has a much greater prophylactic value than strength.19 The emphasis should be placed on endurance and should precede strengthening exercises in a gradual, progressive exercise program (i.e., longer duration, lower effort exercises).

Sport-Specific Exercise

The physical therapist, trainer, physician, and coach must collaborate in designing a sport-specific rehabilitation program. New exercises should closely simulate the sport. Progress should be slow enough to develop an awareness of muscle function. The buildup to maximum performance requires time and patience.

Deep Water Running and Swimming

Walking in a swimming pool is a gentle strengthening exercise for the back. Deep water running is excellent for treating athletes with back pain. The buoyancy of the water helps to unload the spine. Athletes run in the deep end of a swimming pool, normally with the aid of a flotation vest. Water is about 800 times denser than air, so resistance met during water running is greater than when running on land. Deep water running can help to maintain aerobic performance for 6 weeks in trained endurance athletes; sedentary individuals can appreciate significantly increased maximal oxygen uptake. During spine rehabilitation programs, deep water running can be used for maintenance training, but deep water running is not a substitute for conventional training.20–22 Swimming is an excellent exercise for the back, but caution is advised for the novice. The swimming strokes can produce or exacerbate back injury if proper technique is not practiced.

Cycling

Although bicycling is generally considered a healthy form of non–weight-bearing, low-impact exercise, it is important to avoid prolonged flexion in a seated position. A more upright posture is easier on the intervertebral disc, so the upright mountain bike posture is preferred to the flexed racing bike posture. Avoiding the vibration of rough terrain is also logical, making stationary cycling a more reasonable option in the early stages of rehabilitation.

Program Guidelines

The following caveats should be considered when prescribing and monitoring any “return to sport” rehabilitation program23:

1 Low back exercises are most beneficial when performed daily.24
2 The “no pain—no gain” approach when exercising the spine may cause tissue damage associated with certain specific repeated movements.25
3 General exercise programs that include cardiovascular training (e.g., walking) have been shown to be effective for rehabilitation of individuals with low back pain and for injury prevention.26
4 Intervertebral discs are more hydrated early in the morning after rising from bed; it is unwise to perform full-range spinal motions (bending) shortly after rising.27
5 More repetitions of less demanding exercises assist in the enhancement of endurance and strength. Evidence indicates that endurance has more protective value than strength, and strength gains should not be overemphasized at the expense of endurance.19
6 There is no such thing as an ideal set of exercises for all individuals. Although science at present cannot evaluate the optimal exercises for each situation, the combination of science and clinical experience should be used to select an exercise program.
7 Individuals need to be patient and stick with the program. Increased function and pain reduction may not occur for 3 months in some individuals.28

Education

Several studies have documented the value of patient education in the treatment of spine problems.29 Education has been shown to be as valuable to the patient’s recovery as physical therapy. In 2004, Frost and colleagues29 measured the effectiveness of routine physical therapy compared with a single assessment session and advice from a physical therapist for patients with low back pain. They used a multicenter, randomized controlled trial in seven British National Health Service physiotherapy departments. These authors concluded that routine physical therapy was no more effective than a single assessment and advice session from a physiotherapist in treating low back pain.

In the physician’s office, handouts are an excellent source of education and can be reference guides for the patient during rehabilitation activities (Table 29–1). Good preprinted handouts are available from multiple sources, such as the Krames (http://www.krames.com/) or the AAOS (http://www.aaos.org/) websites. Personalizing the handouts gives the athlete assurance in his or her provider’s interest and commitment to the rehabilitation plan and confidence in the treatment plan on leaving the office. With the availability of digital radiography, it is inexpensive to give the patient a copy of his or her radiograph to take home. Being educated regarding the nature of the injury and being part of the rehabilitation team, and not merely the subject, motivates the athlete and can bring about speedier and more complete recovery.

TABLE 29–1 Ways to Avoid Overuse Injuries

1. Use good technique An overhand pitch produces less strain than a side-arm pitch
2. If it hurts, don’t do it “No pain—no gain” is a poor concept. You feel the fatigue of a good workout, but you must recognize the pain of going beyond fatigue to injury
3. Stop when fatigued Avoid the temptation of an extra repetition. Sprints are best done after a rest
4. Increase duration gradually It takes time for the body to respond to increased demand and to strengthen
5. Rest for a time after major increases It is better to alternate 3 hard days with an easy day and then rest for 2 days
6. Quit when you are tired When you have exhausted the glycogen stored in your muscles, your technique falters, and you are prone to injury
7. Do preventive exercises Keep your body in balance by stretching to gain full range of motion and loosening contractures
8. Remember your old injuries When you recall your old injuries, you can work to avoid repeating them
9. Warm up slowly Use gentle stretching and gradually increasing effort to limber up muscles and deep breathing to stimulate the heart and lungs

Return to Play

For the athlete, returning to play is a central issue and may be measured in terms of games missed as opposed to return of fitness. Generally, the athlete can return to play when there is no pain with sport-specific activities and when full range of motion and strength have been recovered. There is no definitive test to measure when that point is reached. Gradual improvement in pain and progression in performing functional activities are predictive of a good prognosis.

Disorders and Treatment

Low Back Pain in Adolescent Athletes

When a physician sees a child with back pain, he or she needs to rule out serious disorders, begin acute care, and anticipate a rehabilitation program that allows the child to return to normal physical activity. Careful evaluation is important; treatment is usually nonspecific. An open-ended interview to hear the patient’s story and expectations is the most valuable assessment instrument. Obtaining a detailed description of the pain is paramount.

The description of pain needs to include its location, duration, onset, and characteristic. If pain is associated with a particular activity or position, that information is helpful for diagnosis. Even with the most aggressive diagnostic workups and follow-ups, however, an organic cause for back pain in adolescents is found only about half of the time.

Lumbar spine pain or low back pain accounts for 5% to 8% of athletic injuries.30 Injuries are often due to poor conditioning of the spine, poor biomechanics, or repetitive stresses placed on the spine by the nature of the sport. Overuse injuries from repeated lumbar hyperextension may be common in children participating in sports such as gymnastics, volleyball, and rowing.

Historical studies show that the correct diagnosis of acute low back pain is established on the first visit only 2% of the time. After 6 weeks, the diagnostic accuracy increases to 15%, and it increases to 30% at 3 months.31 The physician’s initial visit is best used to rule out serious disorders, such as disc herniation or malignant disease. Although less than 1% of back pain complaints are related to serious spine pathology or require emergent treatment, such as neoplasm or cauda equina syndrome, it is important to exclude these conditions and reassure the patient accordingly.

Aggressive diagnostic workup may be deferred and implemented only for patients who do not improve within 3 or 4 weeks. Often, pain resolves without much treatment, and the athlete continues participation. With severe or prolonged pain that prompts medical consultation, a diagnostic workup is appropriate for guiding the treatment.

Back pain that follows an acute injury is usually attributed to muscle strain. There is little scientific evidence showing muscle strain as a back pain generator, however, probably because pain produced by an injury cannot be differentiated to the various soft tissues of the back.32 The pain may be localized or diffuse. The patient frequently relates that more stiffness occurred after a night’s sleep. This type of back pain attributed to muscle strain tends to improve with time.

Growth is not linear, and as growth spurts occur, an imbalance between new length of bone and old length of muscles occurs. These contractures, whether of the hamstrings or other muscles adjacent to the spine, can produce limited motion and pain with athletic activities.

An adolescent with normal musculoskeletal structure may have back pain from poor standing and sitting posture. The typical profile is of lumbar hyperlordosis, thoracic hyperkyphosis, and contracted hamstrings. Radiographs are unnecessary to make the diagnosis or to institute a program of stretching and postural correction.

Mechanical backache secondary to poor posture is more common in sedentary children. Athletic children are less likely to report nonspecific back pain than their nonathletic counterparts. Children who do not walk to school and have a poor self-image of their health in general report more back pain. Multivariate analysis showed that the incidence of low back pain in adolescents is inversely related to time spent doing physical activity (e.g., regular walking or bicycling) and directly related to television or computer time.33

Posture and inactivity contribute to low back pain. The intervertebral discs have the highest fluid content in the morning, which influences the pressure generated on spinal tissues during flexion.34 Avoidance of flexion after arising in the morning significantly reduces nonspecific back pain.35

Plain radiographs are indicated at the time of the first visit if there is a history of severe trauma, loss of neurologic function, or history of malignancy. For an adolescent athlete with a high-risk factor because of a repetitive hyperextension maneuver, oblique views are appropriate for evaluation of the pars interarticularis.

Spondylolysis

Spondylolysis is a stress fracture of the pars interarticularis. It is generally considered to be a low-risk fracture that heals on its own. The fracture occurs most frequently at L5, followed by L4 and L3. Spondylolysis occurs in 5% to 6% of the general population.1 The lesion is usually asymptomatic and appreciated only incidentally on a radiograph. Generally, no single traumatic event causes spondylolysis; rather, repetitive stress produces fatigue defects, and a single event may complete the fracture. These fractures may develop fibrous nonunion or heal in an elongated state.36

The incidence of pars defects is greater in adolescent athletes than in the general population and is a particular clinical problem for this population.37 Sports that require repetitive hyperextension or extension combined with rotation such as gymnastics, wrestling, and weightlifting are more often associated with a stress fracture of the pars interarticularis. White female gymnasts experience a rate of spondylolysis (11%) five times that of the general white female population.38 Certain participants in sports such as diving, weightlifting, wrestling, and gymnastics have disproportionately high rates of spondylolysis. A study of elite Spanish athletes showed the highest rates of spondylolysis in gymnasts and weightlifters followed by throwing athletes and rowers.39 Other reports suggest that a wide variety of sports increase the risk of spondylolysis, including soccer, volleyball, and baseball.40

A major concern for patients with defects in the pars interarticularis is the progressive development of symptomatic spondylolisthesis. The incidence of progressive spondylolisthesis is low (3% to 10%) and mainly occurs during adolescence.41,42 There is no known correlation between active sports participation and either the occurrence or the progression of spondylolisthesis.

Clinical Presentation

Pain may begin after acute injury, or there may be acute exacerbation of mild symptoms present for weeks or months. Lumbar spinal extension or rotation activities are particularly associated with the generation of symptomatic low back pain. Commonly, affected patients have a hyperlordotic posture and hamstring contractures. The classic test during physical examination is to have the patient stand on one leg and lean backward. If the lesion is unilateral, the pain is most often produced by standing on the ipsilateral leg. This test is not definitive but contributes to the diagnosis.

Spondylolysis is a bone lesion and in most patients does not produce a neurologic deficit. Any nerve root signs would suggest an alternative pathology, such as a herniated nucleus pulposus (HNP).

Diagnostic Imaging

Spondylolysis cannot be diagnosed by history and physical examination alone. The key to establishing the diagnosis of spondylolysis is visual confirmation of the pars lesion. The determination of a symptomatic spondylolytic lesion has become more sophisticated with the use of nuclear imaging, CT, and MRI.

A defect in the pars interarticularis is apparent in Figure 29–3, which shows a three-dimensional CT scan. The classic description of this appearance on the oblique view radiograph is that of a collar on the “Scottie dog.” Approximately 20% of the pars interarticularis lesions are seen only on the lateral oblique views, and CT may be necessary to show it.

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FIGURE 29–3 Spondylolysis. Three-dimensional CT scan shows pars interarticularis defect at end of arrow.

Magnetic resonance imaging should be used as the primary investigation for adolescents with back pain and suspected stress reactions of the pars interarticularis. Single-photon emission computed tomography (SPECT) use is limited by the high rate of false-positive and false-negative results and by considerable ionizing radiation exposure.42a

For an adolescent with low back pain, normal radiographs, and a negative bone scan, spondylolysis is ruled out. Other causes should be investigated. MRI may be ordered under these circumstances to rule out disc pathology or other causes for pain in nonosseous tissues. Similarly, adolescents with back pain, positive radiographs, and negative bone scan warrant MRI to investigate further the basis for pain.

Treatment

Most patients with symptomatic spondylolysis do well with conservative treatment.43 The main goals of treatment are amelioration of pain, return to activity, and prevention of recurrence. Treatment modalities include rest, medication, and bracing, alone or in combination. Many pars interarticularis lesions heal with early care, particularly early-stage unilateral defects. Osseous healing is unnecessary to achieve an excellent clinical outcome with full return to activities, although this healing is desirable when possible.

Activity restriction is important to limit pain. Running, jumping, and sport-specific activities that produced the pain should be eliminated for 4 to 6 weeks. Contact and collision sports are not allowed, and hyperextension activities should specifically be eliminated.

Physical therapy has been proved quite effective in the treatment of spondylolysis. Patients with a specific and carefully managed exercise program show significant reduction in pain intensity and functional disability levels.44,45 Therapy should include exercises to increase hamstring flexibility and to strengthen deep core muscles in the abdomen and the lumbar region.46

The role of bracing is difficult to define. A rigid brace is not mandatory for the treatment of symptomatic spondylolysis. Many surgeons begin bracing immediately for spondylolysis, whereas others reserve bracing for patients who do not progress with their conservative program or who experience increasing pain. The main advantage of a brace may be that it promotes better posture.

Various studies have determined that only 9% to 15% of cases of symptomatic spondylolysis or grade 1 spondylolisthesis require surgery.42,47–49 The indications for surgery are progressive slip, intractable pain, development of neurologic defects, and segmental instability associated with pain. Pain alone can be controlled by activity modification and medication and is not an indication for surgery. Surgical treatment is directed at repairing the fracture in the pars interarticularis using bone grafting and internal fixation. Various techniques using wires and screws have been advocated. The technique by Chen and Lee,50 using a pedicle screw and laminar hook, has the advantage of not violating the facet joints, while providing excellent stabilization for healing.

Return to Activity

When follow-up examination reveals no discomfort and pain is well controlled with ordinary daily activities, a low level of sports participation is appropriate. Return to sport can be achieved after 4 to 6 weeks of modified activity. Activity intensity can increase as tolerated. Continued therapy should focus on core strengthening, improvement in posture, and avoidance of hyperextension.

Preventing recurrence is a major goal of treatment. A maintenance fitness program should be included in any workout regimen that is prescribed. Any low back pain that is worsened by extension or twisting should prompt a reduction in activity and increased periods of rest. If these precautions are instituted at the first sign of symptoms, a long course of rest and rehabilitation may be avoided.

Spondylolisthesis

Spondylolisthesis occurs when there is a bilateral defect in the pars interarticularis and one vertebra slips forward relative to the vertebra beneath it. The incidence of spondylolisthesis in athletes is the same as in the general population. No substantiated criteria are available for predicting which cases of spondylolysis will progressively slip, resulting in spondylolisthesis. Patients with dysplastic posterior elements have a higher risk of slip progression. Radiographic studies have shown a strong correlation between slip progression and a more vertical inclination of the superior plate of S1.51,52 Most cases of spondylolisthesis are mild, unlikely to progress, and cease to progress after growth is complete. With mild spondylolisthesis, there is no increased rate of disability and no reason to restrict participation in sports.

Isthmic spondylolisthesis is the type seen in young athletes, excluding the rare cases of congenital absence of facet joints. Bilateral stress fractures of the pars interarticularis are the distinguishing pathology of spondylolisthesis. The stress fractures are unusual in that they occur in young people and rarely heal spontaneously. The only suspected causative factor, other than familial predisposition, is minor or repetitive hyperextension.

Symptoms associated with spondylolisthesis are dull low back pain exacerbated by activity, particularly hyperextension and rotation. Sports requiring repetitive rotation and extension under load, such as gymnastics, football, wrestling, hockey, pole vaulting, diving, and throwing sports, have been incriminated as causative factors in multiple studies.53,54 Typical of mechanical-type pain, rest tends to alleviate the pain.

During the examination the findings of paravertebral muscle spasm, hamstring contractures, and limited flexibility may be dramatic. Kyphosis associated with severe grades of slip flattens the profile of the buttocks and creates a sagittal postural malalignment (Fig. 29–4). A step-off at the lumbosacral level may be palpable.

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FIGURE 29–4 A-C, Spondylolisthesis. Paravertebral muscle spasm is striking. Sagittal imbalance produced by severe slip made clinical diagnosis evident before radiograph was obtained.

Weakness, loss of sensation, and a positive straight-leg raise test are usually absent, differentiating spondylolisthesis from a herniated disc. If radiculopathy is present, the L5 root is usually involved. Cauda equina syndrome has been reported in severe cases owing to nerve root stretch over the dome of the sacrum.55

The diagnosis is easily confirmed by a lateral radiograph of the lumbar spine. The severity of the slip is graded either by the quartile classification of Meyerding or, more commonly, as a percentage of displacement relative to the top of the sacrum. There is consensus that kyphosis is a more important measure of the deformity than displacement.56 The slip angle and sacral inclination are used to describe the sagittal plane deformity.

The treatment of a young athlete with spondylolisthesis is based on the same principles as the population at large, but the desire of the individual to continue sports participation must be considered as well. The age of the patient, the severity and duration of pain, and the degree of deformity all must be considered when formulating a treatment plan. A young, minimally symptomatic patient with a less than 25% slip requires little restriction of activity but should be monitored for progression. Initial flexion-extension lateral radiographs are useful for assessing instability. Serial lateral films at yearly intervals can document any progression of slipping, unless symptoms warrant more frequent follow-up. If the degree of slip is 25% to 50%, the consensus is that the athlete should be restricted from collision sports such as gymnastics and football. If the patient is truly asymptomatic, continued participation may be reasonable as a matter of judgment and cooperation.

Surgical stabilization is recommended for an immature patient with documented progression. Stabilization by spinal fusion is also recommended for slips greater than 50%, even if the patient is asymptomatic.

If the patient still has unremitting, disabling pain after a 6-month program of conservative treatment, certain surgical decisions are made: in situ fusion versus reduction, whether to perform decompression, whether to perform anterior and posterior fusion, and plus or minus bed rest. The debate over these issues remains. In situ fusion is the “gold standard” with well-documented long-term excellent outcomes.57 Isolated removal of the laminar fragment, or Gill procedure, is contraindicated because further progression is common after that procedure.

Absolute indications for decompression are motor deficit and bowel or bladder dysfunction.56 Some surgeons do not perform decompression even with motor or sensory signs because these signs tend to improve with a solid fusion.58 Many surgeons perform a decompression at the time of fusion if weakness, sensory loss, or radicular pain is present, particularly in instances of severe slip. With severe degrees of slip, anterior fusion with or without reduction of the kyphotic deformity can be done using pedicle screw fixation and anterior interbody cages.

Although various methods for reduction of spondylolisthesis are advocated, many are associated with a significant rate of temporary or permanent nerve root damage. Reduction should be done only after wide decompression of the nerve roots, and significant nerve damage may still occur. Return to vigorous athletic participation is not guaranteed after surgery even if the fusion is solid. Most surgeons recommend against any but the least demanding of sports after such a major spine procedure. The decision regarding participation should be delayed until the outcome of surgery is clear.

Lumbar Scheuermann Disease (Juvenile Disc Disease)

The classic radiographic criteria for the diagnosis of Scheuermann disease is kyphosis of the thoracic spine with wedging of 15 or more degrees over three vertebrae.59 Scheuermann disease is associated with endplate changes such as irregularity of the apophyseal ring and Schmorl nodes. The causes of Scheuermann disease, which has been attributed to juvenile osteoporosis, are controversial. This condition affects 0.4% to 8.3% of the general population and causes irregularities in ossification and endochondral growth in the thoracic spine in adolescents and young adults.59 The disease leads to various pathologic changes at the junction of the vertebral body and the intervertebral disc, resulting in pronounced wedging of the vertebral bodies and progressive kyphosis in severe cases. According to various studies, it causes back pain in 20% to 60% of cases and occasionally causes severe deformity of the spine.59

An increased frequency of radiologic abnormalities of the thoracolumbar spine has been reported among young athletes in various sports, such as soccer, gymnastics, water-ski jumping, or wrestling, compared with nonathletes.60–70 Although the origins of typical Scheuermann disease71 have been a matter of controversy,67,72 atypical Scheuermann disease is considered to be strongly associated with trauma or excessive loading of the spine, especially in the flexed posture and during growth spurts.60,67,73 Axial compression forces apparently cause vertebral endplate bulging, whereas compression of the immature spine in flexion is considered to cause anterior intravertebral disc herniation (marginal Schmorl nodes).61,66,67,72–75 Abnormalities of the vertebral ring apophysis are thought to be the result of failure in tension shear, analogous to Osgood-Schlatter avulsion at the knee (Fig. 29–5).68

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FIGURE 29–5 A and B, Juvenile disc disease. This 14-year-old baseball player presented with irritative scoliosis and pain localized to upper lumbar level. Note endplate irregularity and erosion anteriorly at L1-2 level on lateral radiograph.

In 1985, Greene and colleagues72 described back pain and vertebral changes in the lumbar spine similar to changes seen in Scheuermann disease of the thoracic spine. These changes were accompanied by mechanical low back pain. In 1994, Heithoff and colleagues76 saw similar changes on MRI and coined the term juvenile discogenic disease. Their group detected evidence of thoracolumbar Scheuermann disease and multilevel disc disease of the lower lumbar spine in 9% of the subjects studied. The patients ranged in age from 7 to 66, but most were young: Slightly less than half of the patients were younger than 30; 9% were younger than 21. Males outnumbered females 3 : 1. Disc degeneration was found most frequently at the L5-S1 level, followed in order by L4-5 and L3-4. Of patients, 80% showed evidence of substantial degeneration at more than one lumbar level, and 53% had disc herniations involving at least one lower lumbar level.

Heithoff and colleagues76 suspected that a substantial number of young adults have a combination of painful multilevel disc degeneration and lumbar spine changes typical of Scheuermann disease. In their view, both conditions may be caused by an underlying genetic defect in disc structure. It has been estimated that 80% of young patients requiring disc surgery have a genetic predisposition to disc degeneration.76 Juvenile discogenic disease has been statistically associated with athletic activity and repetitive trauma. Most patients can be treated nonoperatively, but a subset have concurrent spinal stenosis, which may require decompression.77

Herniated Nucleus Pulposus

Acute disc herniation, or HNP, is relatively rare in children and adolescents compared with adults. Reports suggest that only 0.5% to 4% of surgically managed HNP occurs in patients younger than 18.78–82 Despite the low incidence, approximately 10% of severe back pain in skeletally immature patients is due to disc herniation.83,84 High-risk activities include weightlifting and collision sports such as football.84 HNP has also been associated with injuries sustained during gymnastics, basketball, baseball, and wrestling.85 Nearly 95% of herniations occur from L4 to S1 and are fairly evenly distributed between L4-5 and L5-S1.80,85 The L3-4 level is affected in only 5% of patients.85

The presenting symptoms of HNP in children differ from the symptoms seen in adults. The profile of an adolescent with HNP includes the presence of tension signs and sciatic scoliosis, without localizing neurologic signs. Most patients present with low back pain, with or without leg pain.84,85 Associated leg pain is seen far less often than in adults (<20% of the time).74 In children, the herniation is thought to be more central and the volume of extruded disc material less than in adults.79,84 Actual rupture of the disc is rare in children.86

Physical examination often reveals an abnormal gait or scoliosis owing to paraspinal muscle spasm.84,85 Nerve tension signs, such as a positive straight-leg raise test, are present in greater than 80% to 90% of patients, and the crossed-leg raise test is positive in more than 50%.79,84,85,87 Objective motor weakness may be present in 40%, with the extensor hallucis longus most commonly affected, and deep tendon reflexes at the knee and ankle are decreased in approximately 40% of patients.85

MRI is a very effective way to image the disc, spinal cord, and nerve roots and because of its noninvasive nature is a commonly used imaging technique. MRI has been shown to detect 100% of symptomatic herniations (Fig. 29–6).88 Herniation is associated with endplate changes, with marrow signal intensity changes on MRI, and with increased cartilage in the material removed during surgery. There is a correlation of marrow signal intensity changes on MRI and the biology of the removed material. Avulsion-type disc herniation is common.89

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FIGURE 29–6 Herniated nucleus pulposus. This 15-year-old wrestler has black bulging disc at L4-5 highlighted by a white dot on MRI.

(Courtesy Charles Burton, MD.)

Conservative treatment is as outlined for nonspecific low back pain. The literature suggests, however, that the overall outcomes of conservative treatment are generally poor. Recommendations suggest a 2- to 4-week trial of conservative management followed by surgical excision of the disc if symptoms have not resolved.85

Indications for surgical excision of the disc include persistent symptoms despite conservative management, cauda equina syndrome, progressive neurologic deficits, and reinjury.84,85 Many authors have reported greater than 90% good to excellent results after surgical excision.80,82,85,90 After surgical excision, low back pain and leg pain resolved within 3 weeks, and neurologic findings resolved after 3 months.80 Long-term follow-up studies show excellent outcomes, including absence of pain and no activity limitations.80,82,90

Apophyseal Ring Fracture

Bone fragments at the posterior vertebral endplate have been given numerous names, such as posterior marginal node; limbus fracture; fracture of the vertebral rim, ring, or endplate; epiphyseal dislocation; and apophyseal ring fracture.91 This condition is unique to adolescents84 and was first described by Skobowytsh-Okolot in 1962.81,92 Endplate fracture was discovered in 20% of patients younger than 21 years and in 33% of patients younger than 17 who were undergoing lumbar disc surgery.93 The overall prevalence is only 0.07% of all patients of all ages undergoing disc surgery. There is a strong male predominance, with 85% of cases occurring in boys; 66% of cases are related to a traumatic event such as weightlifting, heavy work, or sports injury.81 Associations have also been found with Scheuermann disease.94

Hyperextension of the lumbar spine95 and rapid flexion together with axial compression to the vertebral column such as occurs with weightlifting are two proposed mechanisms of apophyseal ring injury.81,84,96 The presenting symptoms of an apophyseal ring fracture are similar to the symptoms seen with HNP—back, buttock, and posterior thigh pain. Symptoms are worse with coughing, sneezing, sports, and prolonged sitting.84 Pain may radiate down one or both legs. The straight-leg raise test is positive, and contralateral straight-leg raise is frequently positive. Paraspinal muscle spasm, lumbar tenderness, scoliosis, intermittent claudication, paraparesis, and cauda equina syndrome have been reported.81,84

Plain radiographs can be useful and show the avulsed fragment in approximately 40% of cases.81,91 This fragment appears as an arcuate or wedge-shaped bone fragment posterior to the vertebral body or disc space. Alternatively, it can appear as a bony ridge on the posterior surface of the vertebral body. MRI may show a defect in the posterior vertebral rim. The fragment may be seen as a low signal area lying posteriorly but can be difficult to distinguish from cortical bone and posterior longitudinal ligament. MRI may be diagnostic in only 22% of cases.91 CT is an excellent imaging study for these fractures because it can define the bony fragment, any associated disc prolapse, vertebral defect, and severity of any associated stenosis in approximately 75% of cases. CT should be considered if MRI fails to show an expected HNP or ring fracture.91

A trial of short-term rest, use of nonsteroidal anti-inflammatory drugs, and physical therapy is indicated. If symptoms fail to resolve after 2 to 4 weeks or if there is progressive neurologic involvement or cauda equina syndrome, surgical excision of the fragment and any associated disc material should be performed.84 Good to excellent results have been reported after surgical excision in nearly all pediatric cases of avulsed ring fracture.

Cervical Spine Injuries

Traumatic neck injuries in young athletes may be to bone, nerve, or soft tissue. The order of incidence is as follows97:

1 Nerve root or brachial plexus neurapraxia (burners)
2 Cervical strains (muscular injury)
3 Disc injury with neck pain only
4 Cervical sprains (ligament injury)
5 Disc herniation with radicular symptoms
6 Transient spinal cord compression secondary to stenosis
7 Fractures

On-Field Examination

If a cervical spine injury is suspected, the physician or trainer should appreciate any spinal pain, altered perception of touch, numbness, and weakness in, or difficulty moving, the extremities. Any player with signs of head trauma, such as disturbed vision, headache, staggering gait, disorientation, or memory loss, should not participate further.

For an ambulatory athlete complaining of pain or spasm in the neck, the physician should localize the tenderness and evaluate for muscle spasm. The physician should evaluate neck range of motion and perform a motor and sensory examination of the extremities. On failing the examination, the athlete should be removed from competition and immobilized in a cervical collar. Alarming signs associated with a cervical fracture are acute torticollis, resistance to any motion, and the patient using the hands to support the head. If the player is unconscious, the presumption is that a cervical spine injury exists, and the neck is immobilized. Any facemask should be removed, but the helmet should be left in place. The player should be immobilized before being moved. Players with persistent or severe pain should be given a prompt radiologic evaluation. Return to participation depends on complete resolution of symptoms and normal radiographs.

Field Treatment of Cervical Fractures

Fractures of the cervical spine are relatively rare. The on-field treatment protocol should be well rehearsed and efficient, however. The minimal equipment includes tools or instruments necessary to remove the facemask, a cervical collar, and a backboard. Such an extensive setup may be impractical, but the medical attendant is well advised to know what emergency medical services are available, such as a well-equipped ambulance. A cell phone or other communication capability should be available on the sideline. The key is advance planning.

Lifting an individual high enough to insert a backboard beneath requires a chief who carefully links the head to the chest and six additional people to lift. If a team has not practiced or there are not six individuals immediately trained and available, the athlete should not be moved until there is adequate assistance to immobilize and transport him or her without incurring additional damage. Instructions for the prehospital care of a spinal cord injury on an athletic field are published online by an interdisciplinary task force.98

Prevention of Catastrophic Injuries to the Cervical Spine in Football

According to Cantu and Mueller99 of the National Center for Catastrophic Sport Injury Research, prevention is related to teaching and enforcing good technique in blocking and tackling and the proper use of well-fitted equipment. Cantu and Mueller99 noted, “The football helmet is not the cause of cervical spine injuries. Poorly executed tackling and blocking technique are the major problems.” The neck should be kept upright, avoiding use of the helmet and facemask as the initial and primary contact point in blocking and tackling. Rules against spearing should be strongly enforced, and athletes should strengthen their necks for further protection in the event of a miss-hit. Cantu and Mueller99–104 stated that being prepared for the treatment and transport of a player with a major spine injury can mean the difference between life and death. That means having a plan and practicing the teamwork necessary for a successful transport.

Cervical Peripheral Nerve Injuries

Stingers or Burners

“Burners” or “stingers” are common injuries to the neck in collision sports such as football, hockey, or diving. A high percentage of football players, especially defensive players, experience burners during their playing career. Other sports in which burners occur include wrestling, backpacking, sledding, skiing, horseback riding, boxing, weightlifting, and climbing.

Burners are caused by either compression or distraction. An asymmetrical axial load on the neck causing compression in the neuroforamen can injure the peripheral nerve root. If the athlete falls directly on the shoulder and the head is distracted away from the shoulder, traction is applied to the nerve root and the brachial plexus. When the cervical spine is hyperextended, hyperflexed, or laterally flexed to the opposite side, the angle between the shoulder and neck is increased beyond the normal range, stretching the brachial plexus.

Symptoms are a severe burning or searing pain in the shoulder and arm associated with loss of sensation and weakness of the arm. The pain may be decreased by abducting the shoulder; this can be achieved by asking the athlete to place a hand on the top of the head. Spurling maneuver is a diagnostic test that reproduces the compression mechanism of injury. The patient’s neck is extended, laterally flexed to the involved side, and rotated to the involved side with axial loading applied while in that position. The burning or searing pain is reproduced. Extension-compression mechanisms are most common, followed by brachial stretch and direct blow mechanisms.105

Burners are best prevented by enforcing the rules on spearing, by strengthening and conditioning the neck, and by proper use of good-quality protective equipment. Shoulder pads are protective equipment for the neck in football. An A-frame design to the shoulder pads brings lateral stability to the base of the neck, preventing lateral tilt while allowing rotation of the head, which occurs at C1-2 (50%). The base of the shoulder pad needs to extend down well on the chest anteriorly and posteriorly to link the chest to the base of the neck. It is almost impossible to prevent extension of the head. The player needs to learn to block with the shoulder and keep the head down so that the opposing player is not contacted with a facemask or the helmet.

Initial treatment for this injury is removal from participation and rest, followed by strengthening exercises of the neck and, finally, careful stretching and restoration of range of motion. Because the pain, paresthesias, and weakness typically last only a few seconds or minutes, these injuries fall into the Seddon classification of neurapraxia. Occasionally, athletes with more severe injuries experience a prolonged recovery period that may last hours to several weeks and may lead to a prolonged loss of time from competition.106–113 Return to play criteria include full range of motion of the neck associated with complete return of arm strength and sensation.

Burners may occur many times during the season, ranging from a transient nerve irritation without residual damage to a complete avulsion of the nerve root from the spinal cord with permanent deficit. Burners are symptoms of injury to either the brachial plexus or a nerve root and must be evaluated systematically.

Quan and Bird114 proposed a classification of peripheral nerve injuries that correlates well with electrodiagnostic studies and prognoses, based on earlier classifications by Seddon114a and Sunderland.114b This classification scheme is useful for diagnosis and advice in individual cases (Table 29–2).

TABLE 29–2 Quan and Bird Classification of Nerve Injury

Type of Injury Mode of Recovery Time to Recovery
Conduction block (neurapraxia) Remyelination of focal segment involved 2-12 wk
Limited axonal loss Collateral sprouting from surviving motor axons 2-6 mo
Intermediate axonal loss Collateral sprouting and axonal regeneration from site of injury 2-6 mo
Severe axonal loss Axonal regeneration 2-18 mo
Complete nerve discontinuity No recovery without nerve grafting 2-18 mo

Data from Quan D, Bird SJ: Nerve conduction studies and electromyography in the evaluation of peripheral nerve injuries. Univ Pa Orthop J 12:45-51, 1999.

Cervical Stenosis

Congenital cervical stenosis is a risk factor for cervical spine injuries.115 Two studies have analyzed the relationship of burners to cervical stenosis in college football players at the University of Iowa and Tulane University.105,116 Burners were more common in players with spinal stenosis as defined by the Torg ratio, especially the occurrence of repeated episodes of neurapraxia. The Torg ratio is defined as the ratio of the spinal canal width to the width of the vertebral body at the same level and is most narrow at C7. These studies suggest that a Torg ratio of 0.7 to 0.8 or lower is high risk. For players with cervical stenosis, the risk of burners is three times that of players without stenosis (Fig. 29–7).

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FIGURE 29–7 Cervical stenosis. This young college football lineman has Torg ratio of 0.4 and is at great risk to continue the sport because of congenital spinal stenosis.

Transient Spinal Cord Compression

Torg and colleagues117 described the syndrome of transient quadriplegia, considered to represent a “neurapraxia of the cervical spinal cord.” This syndrome includes bilateral upper extremity and lower extremity neurologic involvement with no associated fracture or dislocation. It usually resolves within 36 hours. The transient quadriplegia was associated with developmental spinal stenosis, either as an isolated entity or associated with congenital abnormalities, cervical instability, or intervertebral disc disease. The authors noted statistically significant spinal stenosis in all patients who incurred episodes of transient quadriparesis.117,118 They also noted that there was “no evidence that the occurrence of neurapraxia of the cervical spinal cord predisposes an individual to permanent neurological injury.”117

Fracture

Fracture of the Thoracolumbar Spine

Fracture or dislocation of the thoracolumbar spine is unusual. The typical mechanism is an axial load, as from a fall onto the buttocks from a height or at a relatively rapid speed. The injury is usually a relatively benign compression fracture occurring in the lower thoracic spine or at the thoracolumbar junction. Some compression fractures are not easily seen on plain radiographs (Fig. 29–8). When there is significant pain or tenderness using spot radiographs, CT or MRI can aid in identification and localization of the fracture. Any neurologic findings require special evaluation.

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FIGURE 29–8 Thoracolumbar fracture in a 16-year-old horsewoman. Fracture was aligned and stabilized by three-level fusion. Anatomic details are clear on three-dimensional CT scan.

Sacral Stress Fracture

Sacral stress fractures occur almost exclusively in individuals participating in running sports at an elite level. Treatment includes a brief period of limited weight bearing followed by progressive mobilization, physical therapy, and return to sport in 1 to 2 months, after the pain has resolved.

Treatment of spine fractures generally falls into two categories: closed and open. With closed treatment, the fracture is reduced if necessary, and the patient is immobilized in a body cast. Reduction is the primary technique for decompression of the spinal cord. If reduction is not required, the patient is fitted with a brace for comfort.

With open treatment, a surgical procedure is performed to reduce or secure severely displaced or unstable fractures. Open procedures are indicated when two or three of the pillars of the vertebral column are disrupted. Internal fixation is usually required. Pedicle screws and rods are the current devices used for posterior fixation. Anterior fixation with plates and screws is less common. Bone grafting to obtain spinal fusion and biologic long-term stabilization are the final parts of the procedure. Factors to consider when deciding when and if an athlete should return to play after spine fracture are healing, rehabilitation, risk of reinjury, and neurologic status.

Iliac Apophysitis

Apophyseal injuries are a unique injury in adolescent athletes and are associated with skeletal immaturity and repetitive microtrauma. With iliac apophysis involvement, the patient usually presents with back pain localized to the iliac crest, which facilitates diagnosis. There is local tenderness, which is exacerbated by resisted lateral bending and extension. Radiographs are normal. The treatment is conservative for 3 to 6 weeks, during which time the pain predictably resolves.

The typical athlete affected is an adolescent runner. Clancy and Foltz119 described a series of 21 young distance runners, in all of whom pain resolved with alteration of training and rest. As the apophysis closes at the end of growth, even the most recalcitrant cases resolve, similar to Osgood-Schlatter disease of the knee. There are a couple of case reports of avulsion of the apophysis in older teenagers that was surgically repaired, but this is rare.120,121

Tumor

Spine cancers in children are rare. Children 7 to 15 years old with spine infection or tumor tend to present with back, pelvic, or abdominal pain.122 Intradural spinal metastasis pain is a characteristically cramping pain. The physician should take note of back pain that increases with recumbency and keeps the patient awake at night. Progressive pain is characteristic of tumors, not trauma-induced pain. The pain of cancer tends to be constant.

Neoplasia of the spine may originate in either the neural or the osseous elements. Most bony spine tumors of childhood are benign, but they usually cause pain or an irritative scoliosis (Fig. 29–9). Osteoid osteoma is a small, sclerotic, irritative lesion of the posterior spinal elements. The pain is worse at night and is relieved by aspirin or other anti-inflammatory drugs. Although the natural history is for spontaneous resolution of the pain over years, patients do not often tolerate long-term pain well.

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FIGURE 29–9 Osteoid osteoma. Tumor did not show on MRI done for this 14-year-old softball pitcher who presented with back pain and scoliosis. A, SPECT scan was hot at L3. B, CT scan clearly delineates pathologic lesion. Irritative scoliosis corrected spontaneously after tumor was excised.

Osteoblastoma is a larger version of the same process. Osteoid osteoma and osteoblastoma may manifest as stiffness or scoliosis with or without pain. The lesion may not be apparent on plain radiographs. Bone scan is intensely positive and an excellent first supplemental imaging study in children.

Eosinophilic granuloma in the spine produces a flattening of the vertebra, or vertebra plana, rarely with neurologic compromise. Some degree of vertebral regrowth occurs with time in this benign condition. Conservative treatment is indicated if the diagnosis is clear.

Bony malignancies are rare and include leukemia, Ewing sarcoma, and osteosarcoma in bone and neuroblastoma or astrocytoma in the spinal cord. In the absence of actual bone destruction, these tumors may show subtle signs of pressure owing to their growth, such as separation or thinning of the pedicles or scoliosis.

Spinal cord tumors such as astrocytoma or ependymoma are more likely to manifest as extremity weakness, gait disturbance, or scoliosis. Precisely because they are rare, these serious lesions should always be kept in mind. MRI is the study of choice for diagnosis.

Pearls

1 Back pain in an active adolescent athlete is due to spondylolysis until proven otherwise.
2 An open-ended history taken from the patient is the most cost-effective diagnostic tool and worth the time.

Pitfalls

1 Do not perform a cursory nonfocused history and examination for adolescent back pain.
2 Do not jump to surgery before implementing effective nonoperative treatment for back pain.

Key Points

1 Most spine sports injuries in children are chronic injuries resulting from overuse rather than acute injuries secondary to direct trauma.
2 Encouraging the patient to relate his or her history by attentive listening is helpful in determining a differential diagnosis more quickly and accurately.
3 The most common cause of chronic back pain in adolescent athletes is stress fracture or spondylolysis.
4 Sports employing repeated hyperextension maneuvers, such as gymnastics, provide the mechanism for increased stress on the pars interarticularis, which is the site of spondylolysis.
5 Screening radiographs seldom augment a benign history in making a diagnosis. For patients who do not improve in 3 to 4 weeks, CT and MRI can be helpful for diagnosis.
6 Nonoperative treatment is effective for most back pain in children. Spondylolysis, spondylolisthesis, or the rare condition HNP may require operative treatment. Vigorous postoperative rehabilitation may return the athlete to sport.
7 Flexibility is the first priority in treating back pain, with strengthening exercises employed only after a good range of motion has been obtained. Sport-specific exercises are important to prevent reinjury on return to full activity.

Key References

1 Bono CM. Low back pain in athletes. J Bone Joint Surg Am. 2004;86:382-396.

This review focuses on spondylolysis and degenerative lumbar disc disease as the major sources of chronic pain in athletes, while pointing out that most low back pain in athletes is due to self-limited sprains or strains. Although these injuries usually respond to nonoperative treatment, the author found direct repair of recalcitrant defects to be the usual course recommended in the literature. Whether the disc changes are worse than changes seen in the general population is debatable. The author advocates anterior interbody fusion for a patient who does not respond to a directed conservative program.

2 Brodke DS, Ritter SM. Nonoperative management of low back pain and lumbar disc degeneration. J Bone Joint Surg Am. 2004;86:1810-1818.

This review article summarizes the treatment options for nonspecific low back pain, including bed rest, medications, physical therapy, manipulation, braces, and injections. The authors acknowledge that a specific pain generator should be sought and that scientific evidence is lacking to support any particular mode of treatment.

3 Ginsburg GM, Bassett GS. Back pain in children and adolescents: Evaluation and differential diagnosis. J Am Acad Orthop Surg. 1997;5:67-78.

The authors document the differential diagnosis for back pain in children to include spondylolysis, spondylolisthesis, Scheuermann kyphosis, disc herniations, infections, and tumors. They discuss the appropriate tests for early detection and treatment with a rationale for selecting the most appropriate study.

4 McGill SM. Low back exercises: Evidence for improving exercise regimens. Phys Ther. 1998;78:754-765.

This review article documents the biomechanical evidence from the laboratory that can be used to guide the scientific choice of an exercise program for back pain. The author recommends that an exercise program load tissues to strengthen them, while avoiding injury from overexertion. The relative importance of strength, flexibility, and endurance is explored. Specific exercises are described to enhance the stability of the back for rehabilitation and health maintenance.

5 Salminen JJ, Erkintalo MO, Pentti J, et al. Recurrent low back pain and early disc degeneration in the young. Spine. 1999;24:1316-1321.

The authors studied a group of 14-year-old Finnish boys and girls prospectively who had chronic low back pain and compared them with a similar sample of 40 patients who were asymptomatic. The risk of reporting recurrent low back pain up to age 23 years was 16 times as high in the group with early degenerative disc findings. Significant changes included disc protrusion and Scheuermann-type changes on MRI of the lumbar spine.

6 Standaert CJ, Herring SA. Spondylolysis: A critical review. Br J Sports Med. 2000;34:415-422.

The authors based their review on more than 125 articles addressing spondylolysis. They found no controlled clinical trials. Their conclusions were that isthmic spondylolysis is a fatigue fracture of the pars interarticularis, which is more often symptomatic in adolescent athletes. Treatment by activity modification and exercise is usually successful, with symptomatic relief occurring with or without healing of the skeletal defect. Multiple imaging studies have been recommended, and bracing was used in some studies. Rarely, surgery is indicated.

References

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4 Waddell G, McCulloch JA, Kummel E, et al. Nonorganic physical signs in low-back pain. Spine. 1980;5:117-125.

5 Ala-Kokko L. Genetic risk factors for lumbar disc disease. Ann Med. 2002;34:42-47.

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11 Auerbach JA. Towards an evidence-based approach for imaging in evaluation of back pain in children. Ottawa: POSNA; 2005.

12 Brodke D, Ritter S. Nonoperative management of low back pain and lumbar disc degeneration. J Bone Joint Surg Am. 2004;86:1810-1818.

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