Degenerative Lumbar Disc Disease in the Mature Athlete

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Low back pain has an incidence of 5% per year and a prevalence of 60-90% in the general population. Epidemiological studies have found that the frequency of LBP increases as age increases to 60 years; in those older than 60 years, the frequency declines with increasing age.

Disc degeneration has been found in at least one lumbar level in 35% of patients aged 20-39 years and all patients aged 60-80 years.[1]

Certain groups of athletes, including weightlifters and soccer players, appear to have a higher incidence of disc space narrowing and spondylolisthesis, but this does not correlate to a greater incidence of back pain compared with the general population.

Deterioration of the spinal structures is a universal phenomenon with progression of age, occurring in both athletic and nonathletic populations. The intervertebral disc is part of a 3-joint complex; therefore, damage at the level of either the zygapophyseal joints or the disc affects the function of the entire unit.

The deteriorative process most likely begins with the intervertebral disc. Tiny blood vessels enter and exit the disc in the early decades of life, but these vessels become obliterated, leaving the intervertebral disc an avascular structure. Thereafter, nutrition of the disc is supported only through extracellular fluid osmosis. Water is drawn into the disc, and, with motion, the water is partially expelled. This constant movement of water into and out of the disc is thought to allow the disc to remain healthy by bringing in needed nutrients. With the aging process, there is a loss of some of the connective tissue fibers within the disc and an alteration in the properties of the nucleus pulposus. This causes less water to be drawn into the disc and, ultimately, may lead to impairment of nutrition. The water content of a disc in young persons is 88%, but it is reduced to less that 70% in elderly persons.

The deterioration process leads to a stiffening of the intervertebral disc and a change in its shape, causing the disc to lose its ability to distribute load uniformly.

The fibers of the annulus run in different directions at different depths and allow the annulus to accommodate complex motions. Axial rotation of the spine or rotation of a flexed spine may isolate some of the annular fibers and cause small annular tears. These annular tears may or may not be symptomatic; however, in time, they may coalesce to weaken the annulus fibrosus. This can lead to disc bulging, disc space narrowing, or even frank herniation.

In addition, the loss of disc space height may lead to segmental instability and increased forces on zygapophyseal joints, resulting in sclerosis and hypertrophy. The loss of disc height also causes bulging of the annulus into the spinal canal and buckling of the ligamentum flavum. Ultimately, this degenerative cascade can lead to a narrowing of the spinal canal and intervertebral foramen, producing an acquired spinal stenosis.

These degenerative changes begin as early as the second to third decade of life and progress with advancing age. The clinical consequences of this deterioration vary with the age of the patient.

In persons aged 30-50 years, degenerative changes and tears in the annulus of the disc may cause frank herniation of the disc material. This population usually has some compromise of the integrity of the disc, yet the nucleus is still pliable enough to be extrudable, and the spine is mobile enough to produce the required forces for herniation.

With aging of the spine, the nucleus pulposus becomes firmer, spinal motion lessens, and bony overgrowth increases. The intervertebral discs do not herniate as frequently, and spinal stenosis becomes the prominent clinical picture.

Athletes and nonathletes alike are subject to these progressive degenerative changes. However, it is not completely clear how the potentially beneficial effects of training interact with the potentially harmful effects of loading experienced by athletes. The greatest incidence of discogenic disease would be expected to be found in those athletes participating in sports with the greatest axial stresses.

Hellstrom et al found that disc height reduction was much more common in athletes than nonathletes, and, specifically, it is most prevalent in wrestlers and male gymnasts.

Horne et al found a high frequency of disc space narrowing in the thoracolumbar spines of water-ski jumpers.

Other studies have failed to show a correlation between physical loading and increased spinal pathology or low back symptoms, and some evidence suggests that certain types of loading may slow down the degenerative process.

Videman et al reported that former elite athletes overall reported less back pain than control groups in later adulthood. However, they did find an increase in the degenerative changes throughout the entire spine in former weight lifters and in the lower lumbar levels in soccer players when compared to controls. Despite these increased degenerative findings, the former weight lifters and soccer players still had less reported back pain than those in the control groups. This study and others provide some evidence that certain forceful athletic activities may accelerate the degenerative process, but that the degenerative changes seen on imaging studies do not correlate well with clinical symptoms.[2]

The spine is composed of a series of spinal functional units, wherein each unit consists of 3 joints with an anterior and posterior segment. The anterior segment consists of 2 adjacent vertebral bodies and the intervertebral disc between them. The posterior segment consists of the laminae and their processes. One joint is formed between the 2 vertebral bodies, while the other 2 joints are formed by the articulation of the superior articular processes of 1 vertebra with the inferior articular processes of the vertebra above. The intervertebral disc consists of an inner core of gelatinous material called the nucleus pulposus. The nucleus pulposus is enclosed by a ring called the annulus fibrosus.

The individual lumbar nerve roots exit laterally through the intervertebral foramen located on each side of the spinal functional unit. Each intervertebral foramen is bound anteriorly by the vertebral column and intervertebral disc. The intervertebral foramen is bound superiorly and inferiorly by a pedicle, while posteriorly it is bound by the vertebral lamina and zygapophyseal joint. The outer one third of the intervertebral disc is an innervated structure, while the remainder of the disc, including the nucleus pulposus, lacks any innervation.

The sinuvertebral nerves are recurrent branches of the ventral rami that reenter the intervertebral foramina to be distributed within the vertebral canal. These nerves are mixed nerves, formed by a somatic root from a ventral ramus and an autonomic root from a gray ramus communicans. The sinuvertebral nerve supplies the posterior margin of the annulus fibrosus, anterior dura mater, dural sleeve, posterior vertebral periosteum, and the posterior longitudinal ligament. The anterior longitudinal ligament and the lateral aspect of the annulus fibrosus are both innervated by ventral rami and gray ramus communicans. The posterior rami of the spinal nerves supply zygapophyseal joints above and below the nerve, as well as the paraspinous muscles at multiple levels.

The spinal motions that frequently are encountered in many sports and other activities include flexion and extension, torsion (rotational forces), and lateral bending. Additionally, certain sports can subject the spine to shear forces in the anterior and posterior position, as well as to compressive forces in the craniocaudal direction. Protection of the functional units of the spine requires unrestricted and efficient motions between adjacent vertebral segments. Simple flexion/extension movements and even moderate axial compression forces are relatively well tolerated by the disc and the associated joint complexes of the spine.

Rotational forces and combined motions, such as forward flexion with rotation, have been shown to be the most injurious to the disc. Therefore, it is crucial that the supporting stabilizers of the spine, both static and dynamic, are sufficiently strong to offset some of these potentially injurious forces.

The static stabilizers of the lumbar spine include the longitudinal ligaments, the intervertebral discs between the vertebral bodies, and the zygapophyseal joint capsules connecting the posterior elements of the spine. The dynamic stabilizers are comprised not only of the musculature surrounding the lumbar spine, but also include the abdominal and hip muscles, including the hip flexors, extensors, and abductors.

The relationship of the pelvis to the spine is an important consideration when assessing problems in the lumbar spine. Increased lumbar lordosis may result from anterior pelvic tilt, resulting from weak abdominals and/or tight hip flexors. Decreased lumbar lordosis may result from posterior pelvic tilt, resulting from weak paraspinal extensor muscles and/or tight hamstring muscles. The dynamic stabilizers of the spine, when acting synergistically, can directly or indirectly reduce the shear forces to the intervertebral disc and to the zygapophyseal joints of the spine. Of note, athletes overall do not necessarily seem to have stronger back muscles when compared to nonathletes, at least in studies of certain collegiate level athletes.

Sports injuries often involve a twisting or torsion movement, whereas falls are rarely a precipitating cause.

The most common area of complaint among male golfers of the Professional Golfer's Association is the lower back, with an estimated 10-33% of touring professionals reportedly playing with back complaints of some degree. Amateur golfers also identified LBP as their most common golf-related injury. The golf swing frequently has been implicated as a major source of injury to the spine in both professional and amateur golfers. Discogenic LBP most likely develops because of the axial rotation of the lumbar spine at the top of the backswing, with the subsequent uncoiling and hyperextension through the downswing and follow-through.

Several forces act on the lumbar spine during the golf swing. Rotational forces are developed as a result of twisting of the vertebral segments about the spine. Additionally, the spine is subjected to shear forces in the anteroposterior direction, axial compressive forces, and lateral bending forces.

Hosea and Gatt analyzed the various forces on the spine in the swings of amateur and professional golfers.[3] They determined that these forces were actually greater in amateur players compared to professional players. The amateur golfers generated greater lateral bending, anteroposterior shear, and rotational forces, with equal axial compression noted in the 2 groups. They determined that the loads required to cause disc disruption in cadaveric studies were similar to the loads that occur in the golf swing. The importance of trying to minimize forces on the spine through proper swing mechanics becomes clear. Additionally, strengthening the dynamic stabilizers of the spine to counteract the significant forces exerted on the spine during the golf swing is important in both the prevention and treatment of golf-related low back injuries.

Establishing a diagnosis in the mature athlete with lower back or leg complaints begins with obtaining a detailed history and performing a physical examination.

The basic history should include a temporal account of the patient's symptoms and a complete description of complaints. Ask the patient whether their symptoms are associated with participation in a specific sport or activity. If the chief complaint is pain, the primary site, intensity, character, frequency, and radiation of the pain should be determined.

Identify red flags by asking the patients questions regarding the following:

• Trauma, unexplained weight loss, fever, and chills: Answers to these questions may indicate a more serious medical condition that requires further workup.

• Prior episodes of similar symptoms: A history consisting of previous episodes may provide clues to the patient's present condition.

• Previous treatment: The examiner should ask what previous treatments have been tried (eg, use of ice or heat, use of any medications such as acetaminophen, aspirin, and nonsteroidal anti-inflammatory drugs [NSAIDs]). If lumbar injections of any type were a part of the patient's treatment, it is important to know which approach was used and whether fluoroscopic guidance was used because nonfluoroscopic injections have been noted to miss the epidural space in as many as 40% of patients.

• Previous physical therapy: Ask questions about previous participation in a physical therapy program, and attempt to understand the therapeutic exercises used. If, according to the patient, previous physical therapy failed, the physician should ask about the specific therapy approach used, modalities employed, and inclusion of and compliance with a home exercise program. Knowing this information is beneficial for the physician to appreciate the extent and comprehensiveness of previous treatment strategies.

The clinical presentation that results from the underlying degenerative processes in the intervertebral discs of the mature athlete can take several different forms, such as the following:

• As the intervertebral discs deteriorate, small tears can appear in the annulus, and these tears can coalesce to weaken the annulus. At this stage in degenerative disc disease (DDD), back pain is the most common symptom. Discogenic pain usually is worse with prolonged sitting and with flexion of the spine, and it is relieved with extension and moderation of activity.

• Increased pain with coughing, sneezing, or straining also may be consistent with a discogenic cause of back pain.

• If there is progression to frank herniation of the nucleus pulposus, then leg pain, with or without back pain, usually will be the predominant symptom. The distribution of the radiating pain in the extremities depends on which nerve root is compressed or inflamed. Associated motor and sensory deficits may occur, depending on the degree of nerve root involvement.

• This clinical picture usually is seen in persons aged 30-50 years, in whom degenerative changes are present in the disc but in whom the spine is still relatively mobile.

As the spine ages, loss of disc height can lead to segmental instability and secondary spinal stenosis (ie, narrowing of the vertebral foramen). Symptoms include the following:

• Symptoms of spinal stenosis are determined by the location of the compression on the neural elements. Typically, compression from central stenosis results in neurogenic claudication with unilateral or bilateral discomfort in the buttocks, thighs, or legs.

• Symptoms are produced by standing or walking, and they are relieved by adopting a lumbar flexed posture.

• Symptoms can include pain, numbness or paresthesias, weakness, or a combination of these symptoms.

• When the neural foramen is the site of stenosis, the clinical features are different from those of central canal stenosis. Patients can present with unilateral sciatic pain (usually L5 or S1 nerve root irritation) that is provoked by standing or walking and relieved by sitting or flexing the lumbar spine.

A retrospective study found that in patients with early to middle-stage lumbar disc degeneration, discrepancy of the disc height between the standing and supine positions can aid in screening for disc degeneration–related low back pain (LBP). In patients with intractable discogenic pain, the disc height discrepancy ratio was significantly higher than that for persons with mild LBP (14.55 vs 1.47, respectively), although the disc degeneration level was similar between both groups.[4]

A comprehensive physical examination of the mature athlete with LBP should include an in-depth evaluation of the neurologic and musculoskeletal systems. Combining the findings of the history and physical examination increases the overall predictive value of the evaluation process. The examination should include the following:

• Inspection

  • The examination begins with observation of the patient during the history portion of the evaluation. Note any paraspinal spasms, scoliosis, an increase or decrease in lordosis, muscle atrophies, or asymmetries.

  • Observe the iliac crests for any difference in height that may indicate a functional leg length discrepancy.

  • When acute disc herniation is present with nerve root involvement, the patient often will list to one side. With a disc herniation lateral to the nerve roots, the patient will list away from the side of the irritated nerve root in an attempt to draw the nerve root away from the disc. Likewise, when the herniation is medial to the nerve root, the patient will list toward the side of the lesion.

• Palpation

  • Determine whether any tender or trigger points can be appreciated in the lumbar paraspinal musculature and whether muscle spasm is present. Tenderness also may be present along muscles in which symptoms are referred, such as in the gluteal region and in the lower extremity.

  • Palpation of the lumbar spine in the midline sometimes can elicit pain at the level of a symptomatic intervertebral disc.

• Range of motion

  • Determine range of motion (ROM) for flexion, extension, lateral bending, and rotation.

  • On forward flexion, the lumbar spine should move from its normal lordotic curvature to a straight or slightly flexed posture. The Modified Schober test may be used to measure the amount of flexion occurring in the lumbar spine. A point is marked midway between the 2 posterior sacroiliac spines; then, points 5 cm below and 10 cm above that point are marked. The distance between the 3 points is measured. The patient then is asked to flex forward, and the distance is measured again. The distance between the 2 measurements is an indication of the amount of flexion occurring in the lumbar spine. Less than a 4-cm change between the 2 measurements suggests a loss of normal segmental motion in the lumbar spine.

  • In addition to ROM of the spine, assess the other lower extremity joints because pain referral patterns may be confused with focal peripheral involvement. For example, a patient with anterior thigh pain and knee pain may actually have a degenerative hip condition, not an upper lumbar radiculopathy. Reproduction of the patient's pain with hip internal rotation, external rotation, or other provocative hip maneuvers may further distinguish hip pathology from spine involvement.

• Muscle strength

  • Manual muscle testing is important to determine whether weakness is present and whether the distribution of weakness corresponds to a single root, to multiple roots, or to a peripheral nerve or plexus.

  • Additionally, evaluate the dynamic stabilizers of the lumbar spine, including the abdominals and the muscles about the hip, to include the hip flexors, extensors, and abductors.

• Flexibility

  • Inflexibility of the musculature about the pelvis has a direct result on the mechanics of the lumbosacral spine.

  • Increased tightness of the hamstrings or gluteus maximus muscles can cause a posterior tilt to the pelvis, reducing the lumbar lordosis. Tightness of the rectus femoris and iliopsoas muscles anteriorly can cause an anterior tilt to the pelvis, increasing the lumbar lordosis. Both of these effects can cause increased force to be distributed to the lumbar spine and can predispose individuals to LBP.

• Sensory examination

  • On sensory examination, a dermatomal decrease or loss of sensation should be found in patients with clear-cut radiculopathy, whether caused by disc herniation or foraminal stenosis.

  • Patients with radiculopathy also may have hyperesthesia to light touch and pinprick examination. However, the sensory examination can be quite subjective, since it requires patient response.

• Muscle stretch reflexes

  • Muscle stretch reflexes are helpful in the evaluation of patients presenting with limb symptoms suggestive of a radiculopathy.

  • Neither a decrease nor an increase of these reflexes can be interpreted as definitely abnormal. The asymmetry of reflexes is most significant; therefore, a patient's reflexes must be compared with the contralateral side.

• Straight leg raising test

  • Provocative maneuvers, such as straight leg raising, may provide evidence of increased dural tension, indicating underlying nerve root pathology.

  • Unilateral straight leg raising primarily tests the L5, S1, and S2 nerve roots, with symptoms further provoked by ankle dorsiflexion. Straight leg raising test is only considered positive if pain occurs when the leg is elevated 30-70° and when pain travels down below the knee. Minimal nerve root tension occurs below 30° of elevation, and pain elicited above 70° is most likely related to tightness within the hamstrings or gluteal muscles.

  • Elevation of the asymptomatic lower extremity causing pain in the symptomatic side (crossed straight leg raising sign) is suggestive of a herniated disc.

• Peripheral vascular examination

  • Examination of the peripheral circulation is important, especially when attempting to differentiate between the neurogenic claudication seen in spinal stenosis and the vascular claudication seen in peripheral vascular disease.

  • Examination of the posterior tibial and dorsalis pedis arteries should be performed, as well as examination of the skin temperature and inspection for the presence of trophic changes seen with ischemic disease.

• Pain centralization maneuvers: Attempts at pain centralization through postural changes, such as lumbar extension, may suggest a discogenic cause for the back pain and may help in determining the success of future treatment strategies.

• The clinical features in many cases of radiculopathy are inadequately explained by anatomic abnormalities alone. High levels of an inflammatory enzyme, phospholipase A2, have been identified in lumbar herniated and degenerative discs. Saal et al and other authors support the concept that the clinical features of many patients with lumbar disc disease may be explained by inflammation caused by biochemical factors working alone or in combination with the mechanical deformations described above.[5]

Plain radiography

Plain radiographs traditionally have been ordered as the initial step in the workup of lumbar spine pain. The main purpose of plain radiographs is to detect underlying structural pathologic conditions. Selective criteria can be used to improve the usefulness of plain radiographs.

These studies generally are not recommended during the first month of symptoms in patients without any red flags. An exception to this would be if the low back symptoms are related to a sports-related injury where there is suspicion of fracture.

Three basic views of the spine are routinely ordered for workup of LBP: the anteroposterior view, the lateral view, and the coned-down lateral view of the lower 2 interspaces. Oblique views can be obtained to further visualize the facet joints, the pars interarticularis, and the neuroforamen.

Radiographs detect the characteristic degenerative changes of the spine, and, in some cases, they may localize a particular site of degeneration that may be causing symptoms.

Bone scanning

Bone scans can be helpful when tumor, infection, or fracture (occult or traumatic) is suspected.

Bone scans are limited by relatively poor spatial resolution of the pertinent anatomy of the spine.

Single-photon emission computed tomography scan provides superior anatomical resolution compared with uniplanar radionuclide images.

Positive bone scan findings generally should be followed by confirmatory imaging, such as MRI or CT scan, which provides for greater pathoanatomical detail of the spine.

CT scanning

CT scan of the lumbar spine provides superior anatomical imaging of the osseous structures of the spine and good resolution for disc herniation. However, its sensitivity for detecting disc herniations when used with myelography is inferior to MRI.

As with MRI, the frequency of false-positive findings in asymptomatic patients is high. CT scan is best used when a fracture is suspected, but it can be used in the detection of disc injury in patients who cannot undergo MRI. In addition, CT scan is recommended when more detailed imaging of the bony architecture is important.

Myelography

A myelogram involves penetration of the subarachnoid space and generally is not indicated in the evaluation of acute LBP. Generally, it is reserved as a preoperative test, often in conjunction with a CT scan. This provides a detailed anatomic picture, particularly of the spinal osseous elements, and can be used to correlate examination findings and assist in preoperative planning.

Myelography rarely is used in the nonoperative evaluation of patients with acute LBP, except in cases in which the clinical picture supports a progressive neurologic deficit and the MRI and electromyogram are nondiagnostic.

MRI

MRI provides high-resolution imaging and therefore allows accurate description of intervertebral disc pathology. T2-weighted images are sensitive to disc degeneration because there is a loss of signal primarily within the nucleus as a result of altered hydration status.

Sagittal sections reveal the vertebral column, intervertebral discs, spinal canal, and spinal cord. Axial views show the disc or vertebral body, the spinal cord, and the spinal roots, among other structures. Neural element encroachment seen on the sagittal view should be confirmed on the axial view.

MRI also is useful for assessment of canal encroachment and spinal stenosis. MRI is useful for imaging the broad spectrum of pathology associated with DDD in the mature athlete.

As with CT scanning, MRI is very sensitive, and not all abnormalities detected are clinically relevant. Jensen et al found in their study of 98 asymptomatic people that 64% of subjects without back pain had a bulge, protrusion, or extrusion of the intervertebral disc at one level, and 38% had an intervertebral disc abnormality at more than one level. Additionally, they found that the prevalence of disc pathology varied according to the age of the patient. In the group of asymptomatic subjects aged 60 years or older, they found that 80% had disc bulges at one or more levels. Therefore, because bulges and protrusions on MRI in people with LBP may be coincidental, each MRI study must be interpreted with regard to the patient's history, physical examination, and other diagnostic tests.

Electrodiagnosis

Electrodiagnostic studies, including nerve conduction studies, needle electromyography, and somatosensory evoked potentials, should be considered an extension of the history and physical examination and not merely a substitute for a detailed neurologic and musculoskeletal examination. These studies are helpful when the diagnosis remains unclear in patients with limb pain. They also are helpful in excluding other causes of sensory and motor disturbances, such as peripheral neuropathy and motor neuron disease. Additionally, they can provide useful prognostic information by quantifying the extent and acuity of axonal involvement in radiculopathies. Electrodiagnostic studies performed less than 3 weeks after the onset of symptoms may result in a false-negative study since evidence of denervation does not appear until 2-3 weeks postinjury.

Performing late responses, such as the H-reflex, can provide valuable information regarding the proximal nerve or nerve root involvement. The H-reflex is both a sensitive and specific marker for involvement of the S1 root and is prolonged from the time of symptom onset.

Electrodiagnostic testing usually is not necessary in patients with a clear-cut radiculopathy or in patients with isolated LBP. When imaging studies reveal multiple abnormalities, which are common in older individuals with degenerative changes, electrodiagnosis can assist in localizing the etiology of the patient's symptoms.

Discography

Discography is rarely necessary in the evaluation of LBP and is not recommended within the first 3 months of treatment. Discography can be helpful in patients who have not responded to a well-coordinated rehabilitation program or who have normal or equivocal MRI findings. In such cases, discography may have some benefit in localizing a symptomatic disc as the etiology of nonradicular back pain.

A positive discogram must include a concordant pain response. This includes reproduction of symptoms upon injection of a symptomatic disc, a nonpainful response upon injection of control discs, and observed annular pathology on postdiscography CT scan, if used.

Discography most often is used prior to contemplating intradiscal electrothermal annuloplasty, also referred to as intradiscal electrothermal therapy (IDET), or surgical fusion for unremitting pain due to a symptomatic internal disc disruption. The characteristic feature of internal disc disruption is a radial fissure extending to the innervated outer third of the annulus fibrosus.

Some have found discography followed by a CT scan to be a more precise technique to delineate discovertebral pathology with sensitivities similar to or better than MRI and CT scan/myelography.

Discography must be used with care since a significant percentage of individuals with positive discograms improve without surgery. In addition, certain groups of patients tend to overreport pain during discographic injection.

Carragee et al found that provocative lumbar discography, when performed on volunteer subjects with no history of LBP, evoked little pain in those without chronic pain conditions, compensation issues, or abnormal psychometric testing.[6]

They found that when this procedure was performed in subjects with abnormal psychometric testing, particularly those with somatization features, chronic pain, and ongoing compensation litigation, the subjects frequently had very painful responses to disc injections.

In light of their findings, the usefulness of discography in this latter group of patients is questionable. At the very least, their study identifies the need for a proper screening method in patients undergoing this diagnostic modality.

Despite its flaws, discography still remains the only quasi-objective provocative test for disc-mediated pain. CT discography recently has received attention because it may be a good predictor of outcome following lumbar fusion for patients with intractable back pain.

Rehabilitation Program

Physical Therapy

During the acute phase of a rehabilitation program for discogenic LBP, the focus of treatment is on reducing pain symptoms. Instruction in posture and body mechanics in activities of daily living is aimed at protecting injured structures, reducing symptoms, and preventing further injury. Educate patients to avoid positions that increase intradiscal pressure, such as sitting, bending, and lifting. A short course of bed rest (1-2 d) may provide some beneficial effects via pain modulation and reduction of intradiscal pressure, but longer courses of bed rest yield detrimental effects on bone, connective tissue, muscle, and cardiovascular fitness.

Emphasis on activity modification, rather than strict bed rest, is recommended to avoid the unwanted effects of immobilization.

Modalities, such as electrical stimulation, should be limited to the initial stages of treatment so that patients can quickly progress to more active treatment that includes restoration of motion and strengthening. Electrical stimulation can be combined with ice to enhance its analgesic effect.

Surgical Intervention

Surgical consultation is warranted in patients with acute discogenic back or leg pain when there is progressive neurologic loss. Large midline disc protrusions with cauda equina syndrome, characterized by saddle anesthesia (ie, perineal numbness) and bowel or bladder dysfunction, require urgent surgical decompression. Other indications for surgical intervention are less clear-cut. No data show that operative intervention restores neurologic function more rapidly than nonoperative treatment. Saal, in his description of the natural history of lumbar disc herniation, notes that patients who recover without surgery usually demonstrate signs of improvement in the first 3-6 weeks from the time of onset.[5] Many authors suggest that it is reasonable to operate on patients with significant neurologic loss (eg, a foot drop) that has not improved by 6 weeks postinjury.

Other Treatment

Lumbar epidural steroid injections (LESIs) have been used to treat a variety of low back conditions. Controlled studies have evaluated the effectiveness of epidurals in the treatment of lumbar conditions, with some studies showing success in certain subgroups of patients with discogenic back pain.

A study by Lutz showed a success rate of 75.4% using selective nerve blocks in conjunction with oral medications and physical therapy for the treatment of acute herniated discs. Most controlled and uncontrolled studies indicate that LESIs provide short-term benefits for patients with lumbar radiculopathy and can be an important component to an overall treatment approach. Meta-analyses have failed to show a long-term benefit from these injections.

A randomized, controlled trial by Khot et al demonstrated that intradiscal steroid injections compared with saline injections (control group) in men with spinal discogenic pain did not improve the clinical outcome in pain reduction.[7] The mean age of these patients was approximately 43 years. In a prospective trial by Butterman comparing LESIs to discectomy for lumbar disc herniation, 42-56% of the 50 patients randomized to LESI reported successful outcomes. Another study by Butterman showed LESIs to be effective, specifically in patients with advanced DDD and those with MRI findings of discogenic inflammation and adjacent end-plate changes.[8, 9]

Nonradicular pain has been shown to be predictive of poor treatment response rates; therefore, LESIs typically are reserved for patients with radicular features. Mature athletes with DDD who have localized axial pain are not appropriate candidates for these injections. Individuals with radicular features as their presenting clinical symptom may benefit from an epidural injection to allow facilitation of a comprehensive rehabilitation program. However, in older populations, radiculopathy is more likely to result from spinal stenosis (spina canal or foramina), and epidural injections have not been found to be nearly as effective in cases of radiculopathy secondary to abnormal bone structure compared with radiculopathy secondary to disc herniation. Therefore, the role of LESIs in the mature athlete with DDD appears to be limited. Furthermore, most studies indicate that LESI is most likely to be successful in patients who have had symptoms for less than 6 months.

Overall, more investigations of LESIs are needed to firmly establish the population best served by this treatment. Randomized, controlled trials are needed, given the poor design of many existing studies, with no control groups, heterogeneous populations, and injections performed without fluoroscopic guidance.

Rehabilitation Program

Physical Therapy

Once the painful symptoms are controlled during the acute phase of treatment, strengthening exercises for the lumbar spine and associated muscles can be initiated. The clinical presentation of DDD in the mature athlete can be quite variable; therefore, no single group of exercises can treat all patients effectively.

The McKenzie exercise approach to disc pathology does not commit to either flexion or extension activities, but rather it identifies postures and motions that centralize referred LBP. The McKenzie program is initiated only after a comprehensive assessment determines which positions most effectively centralize a patient's pain. These exercises eventually are incorporated into a more comprehensive spinal rehabilitation program that includes spine stabilization exercises.

In spine stabilization exercises, the goal is to teach the patient how to find and maintain a neutral spine during everyday activities. The neutral spine position is specific to the individual and is determined by the pelvic and spine posture that places the least stress on the elements of the spine and supporting structures. In classic discogenic pain, the neutral spine has an extension bias. In classic posterior element pain or spinal stenosis, which may both result from the ongoing degenerative cascade initiated by disc degeneration, the neutral spine may have a mild flexion bias. Dynamic lumbar stabilization may be used with the McKenzie approach to provide dynamic muscular control and to protect the spine from biomechanical stresses including tension, compression, torsion, and shear. Spinal stabilization provides this control and protection by emphasizing the synergistic activation of the trunk and spinal musculature in the midrange position.

Strengthening of the abdominal and gluteal muscle groups is stressed because these muscles form part of the dynamic stabilizers of the spine and attach to the thoracolumbar fascial support system, one of the potential spine stabilizing structures. Spine stabilization exercises lend themselves to the mature athlete because the overall goals of this comprehensive exercise program are to reduce pain, to develop the muscular support of the trunk and spine, and ultimately to diminish the overall stress to the intervertebral disc and other static stabilizers of the spine.

In addition to specific spine stabilization concepts, the spine should also be assessed in conjunction with the entire kinetic chain to which it is linked. Restrictions or weaknesses in one part of the chain can manifest as problems in another region. For example, restrictions in hip ROM can lead to increased stresses on the lumbar spine during certain activities (eg, golfing), increasing the chance for dysfunction and injury. Therefore, elements of the entire kinetic chain should be targeted as part of a comprehensive rehabilitation program.

Mature athletes with DDD of the spine should have lower-extremity closed-kinetic chain exercises incorporated into their therapy regimens. These exercises also should be included in the regimen for those who participate in activities involving the upper extremities, since a great deal of the force generated in overhead sports occurs in the trunk and lower extremities. In athletes who participate in activities involving the upper extremities and who have LBP, both upper- and lower-extremity closed-kinetic chain exercises should be included in the rehabilitation program.

Rehabilitation Program

Physical Therapy

The maintenance phase represents the final phase of the rehabilitation process. Eccentric muscle strengthening exercises, including more dynamic conditioning exercises (eg, with a large gym ball), are added to the program. In addition, sport-specific training should be incorporated so that the mature athlete can maintain a neutral spine in all recreational activities.

The goals of a comprehensive spinal rehabilitation program have been met when the mature athlete no longer demonstrates the original symptoms, full ROM of the spine is present, strength and flexibility are within normal limits, and good sport-specific mechanics are demonstrated.

Surgical Intervention

Lumbar fusion

A general lack of consensus exists regarding the indications for lumbar fusion in patients with degenerative disc disease (DDD). The natural history of DDD has not been shown in scientific studies to be treatable with great success by any method of lumbar fusion.

An Cochrane review of surgical interventions for degenerative lumbar disease found inconclusive results for a firm conclusion on the effectiveness of fusion surgery.[10] Two randomized clinical trials compared spinal fusion with conservative treatment: a Swedish trial reported by Fritzell et al found that patients who underwent surgery had significant improvements in pain and significantly higher rates of return to work[11] ; the second trial, a Norwegian trial reported by Brox et al and Keller et al found no significant differences in outcomes in surgery compared with a conservative rehabilitation approach.[12, 13]

A significant morbidity associated with lumbar fusions involves juxtafusional degeneration, which may require reoperation within approximately 10 years of a successful fusion surgery. Some studies have suggested hastening of degeneration of spinal functional units adjacent to the fused vertebrae. Furthermore, fusion causes limited range of motion, a consequence that has become less acceptable as a treatment outcome.

Suratwala et al studied the outcomes of 3 or more motion segment fusions of the lumbar spine in patients with low back pain caused by multilevel degenerative disc disease. In 65 of 80 patients, solid arthrodesis was achieved, with adjacent segment degeneration being noted in 11 patients. Oswestry Disability Index scores improved from 49.8 to 35.1, and Roland Morris scores improved from 17.6 to 12.2. According to the authors, the surgical treatment of lumbar degenerative disc disease by 360º fusion should be considered in selected patients, with the goal of reduction, rather than elimination, of disability.[14]

Arnold et al assessed the fusion rate and outcome in 89 patients with degenerative disc disease using machined posterior lumbar interbody fusion (PLIF) allograft spacers and posterior pedicle fixations. Of the 89 patients, 65 underwent 1-level PLIF and 24 underwent 2-level PLIF. At 12 and 24 months, flexion-extension radiographs showed a fusion rate of 98%. Of the 72 patients who reached 12-month follow-up, 86% reported decreased pain and disability measured by the Oswestry Disability Index, and 74% reported decreased pain measured by the SF-36 Bodily Pain Score. Graft-related complication rate was 1.61%. The authors concluded that PLIF is safe and effective for low back pain caused by degenerative disc disease when performed with machined allograft spacers and posterior pedicle fixation, and they noted that the patients in this study had outcomes that were equal or superior to the outcomes in previous PLIF series.[15]

Disc arthroplasty

A developing alternative to lumbar fusion surgery emerging in modern medicine is total lumbar disc replacement surgery, also known as disc arthroplasty. The desire for this approach to degenerative lumbar disc disease is to treat low back pain while avoiding the limitations of surgical fusion, including limitations in ROM and segmental instability or degeneration of adjacent spinal segments. Candidates for disc arthroplasty are limited to patients without significant facet joint dysfunction because this has been associated with poor outcomes.

Disc replacement devices continue to undergo investigative trials. The Charite artificial disc, which is commercially available in the United States and has been limited to disease of L4-L5 or L5-S1. European data with complication rates of lumbar disc arthroplasty give pause to the use of this intervention, as does the overall limited long-term follow-up and randomized clinical trials currently available. Furthermore, the average age of patients who are candidates for total disc replacement are typically younger than those who are candidates for total joint replacements, further highlighting the need for longevity of the implanted devices.

To the authors’ knowledge, the medical literature does not yet provide enough data to support or refute firm conclusions on the safety and applicability of disc arthroplasty in the mature athlete.

Nucleus pulposus replacement

An emerging technology is nucleus pulposus replacement. This surgical intervention is designed to increase disc space height in the degenerating disc and decrease the transmission of forces onto the remaining annulus, facet joints, and other stabilizing structures. Compared with total disc replacement, this surgical option involves less surgical exposure, potentially provides biomechanics similar to native discs, and the advantage that a failure of nucleus pulposus replacement still allows for revision with fusion if necessary. The implants currently under investigation are primarily composed of hydrogels that an absorb water and release water when loaded.

Limitations in implant materials include toxicity of the materials and the danger of their extrusion from the disc space. One such implant with the most thorough studies yet is the Prosthetic Disc Nucleus, which is designed to absorb 80% of its weight in water. It has been shown in a small study by Schonmayr et al to restore disc space height and normal motion.

Other Treatment

Intradiscal electrothermal therapy (IDET) involves the insertion of an electrothermal catheter into a painful intervertebral disc under fluoroscopic guidance. Thermal energy delivered by the catheter results in breakdown and restructuring of collagen fibers in the annulus. Several mechanisms by which IDET might relieve discogenic pain have been proposed, including an alteration of annular tears, stiffening of the intervertebral disc, or simple ablation of nerve endings in the annulus.

Proponents of the procedure believe that IDET may be indicated for patients who have degenerative disc changes with concordant pain on discography and a chronicity of LBP for all conservative management techniques have failed. A preliminary nonrandomized study by Saal and Saal on a small number of patients who had IDET revealed an improvement in function by a visual analog scale and sitting tolerance time.[5]

Two randomized clinical trials demonstrated extremely poor results,[16, 17] but a trial by Pauza et al reported significant improvement in pain; however, this last study was conducted on a highly select group of patients.[18] A prospective trial, by Park et al, in Korea showed that 84% of the 25 patients enrolled had persistence of pain and, overall, reported poor satisfaction after IDET.[19] The trials for IDET have been small, and few have rendered applicability and firm conclusions.

A study by Jabłońska et al found depression symptoms in 47.3% of the 188 patients with cervical or lumbar degenerative disc disease before surgery (11.7% cervical; 35.6% lumbar) and in 31.1% of patients at 6 months follow-up (7.5% cervical; 23.6% lumbar).[20]

Criteria for return to play require the mature athlete to have an absence of signs or symptoms of the original injury (especially if there were radicular symptoms), full ROM, strength and flexibility to within normal limits, and good sport-specific mechanics. Mature athletes must be aware of their own limitations; this awareness is particularly important for the individual gradually returning to a competitive level of activity after injury.

Patient education is an important factor in the prevention of low back injury in the mature athlete. Minimizing forces on the spine through proper mechanics in specific sporting activities is important. Additionally, strengthening the dynamic stabilizers of the spine to counteract the significant forces exerted on the spine during certain athletic activities also is important.

Maintaining proper flexibility also is believed to play a significant role in the prevention of back injury in athletes of all ages. Additionally, improvement in aerobic fitness can increase blood flow and oxygenation to all tissues, including the muscles, bones, and ligaments of the spine, and it would be a reasonable addition to any rehabilitation and prevention program. Seasonal athletes should be encouraged to cross-train year round or at least undergo preconditioning before participating in their particular sport.

For patient education resources, see the Breaks, Fractures, and Dislocations Center; as well as Back Pain and Vertebral Compression Fracture.

Various medications have been used in the treatment of LBP from DDD, to include acetaminophen, NSAIDs, muscle relaxants, opioid analgesics, oral corticosteroids, and antidepressants. No standard doses have been established for oral prednisone in the treatment of lumbar radicular pain. Before prescribing these medications, the physician should be aware of the contraindications, common adverse effects, and mode of action of each agent.

Class Summary

Offer additional anti-inflammatory effects compared with acetaminophen. The dose to produce anti-inflammatory effects differs substantially from that for analgesic effects. Most NSAIDs achieve only analgesic effects because the dose prescribed is too small and too infrequent to produce an anti-inflammatory effect. Risks are associated with NSAIDs, especially in the elderly population and in those with a history of peptic ulcer disease, hypertension, or renal insufficiency. Newer generation NSAIDs selectively interact with the COX-2 receptors and have a lower gastrointestinal risk. Prolonged use of these medications generally is not recommended for most patients with low back problems.

Ibuprofen (Motrin, Ibuprin)

DOC for patients with mild to moderate pain. Inhibits inflammatory reactions and pain by decreasing prostaglandin synthesis.

Celecoxib (Celebrex)

Inhibits primarily COX-2. COX-2 is considered an inducible isoenzyme, induced during pain and by inflammatory stimuli. Inhibition of COX-1 may contribute to NSAID GI toxicity. At therapeutic concentrations, COX-1 isoenzyme is not inhibited, thus GI toxicity may be decreased. Seek lowest dose of celecoxib for each patient.

Class Summary

The use of opioids in the treatment of LBP should be limited to pain that is unresponsive to alternative medication. Opioids can be prescribed for acute disc herniation or other back injury to facilitate participation in an active rehabilitation program. They should be used on a defined dosing schedule and not on an as-needed basis. In addition, adequate baseline dose should be established to achieve analgesia. The use of nonopioid analgesics, such as tramadol, also is an option.

Oxycodone (OxyContin)

Drug combination indicated for the relief of moderate to severe pain.

Tramadol (Ultram)

Inhibits ascending pain pathways, altering perception of and response to pain. Inhibits reuptake of norepinephrine and serotonin.

Class Summary

Medications categorized as muscle relaxants may be helpful in some patients with LBP and seem to have additional beneficial effects when used in conjunction with NSAIDs. Muscle relaxants can be used as short-term adjunctive medications, and they should be taken at bedtime to take advantage of their sedating effects.

Cyclobenzaprine (Flexeril)

Skeletal muscle relaxant that acts centrally and reduces motor activity of tonic somatic origins influencing both alpha and gamma motor neurons. Structurally related to tricyclic antidepressants and thus carries some of their same liabilities.

Class Summary

Potent anti-inflammatory medications represent theoretically useful agents in the treatment of patients with radiculopathy due to local inflammation resulting from disc injury or herniation. No standard doses have been established for oral prednisone in the treatment of lumbar radicular pain.

Prednisone (Deltasone, Sterapred, Orasone)

Decreases inflammation by suppressing migration of polymorphonuclear leukocytes and reversing increased capillary permeability.

Class Summary

Tricyclic antidepressants (TCAs) have been well studied and supported as useful analgesics in patients with pain of neurogenic origin. TCAs also can be helpful as adjuncts for pain and sleep if used at bedtime. Initial doses should be low, and subsequent doses can be slowly increased to minimize adverse effects.

Amitriptyline (Elavil)

By inhibiting reuptake of serotonin and/or norepinephrine in presynaptic neuronal membrane, may increase the synaptic concentration of serotonin in the CNS.