Spondylolysis

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Spondylolysis
Spondylolysis.jpg
Spondylolysis (wrong descriptions: the upper 3 arrows should be partes interarticulares)
Specialty Orthopedics
Diagnostic method X-ray, MRI

Spondylolysis is a defect or stress fracture in the pars interarticularis of the vertebral arch. [1] The vast majority of cases occur in the lower lumbar vertebrae (L5), but spondylolysis may also occur in the cervical vertebrae. [2]

Contents

Signs and symptoms

In majority of cases, spondylolysis presents asymptomatically, which can make diagnosis both difficult and incidental. [3] When a patient does present with symptoms, there are general signs and symptoms a clinician will look for:

Cause

The cause of spondylolysis remains unknown, however many factors are thought to contribute to its development. The condition is present in up to 6% of the population, the majority of which usually present asymptomatically. [7] Research supports that there are hereditary and acquired risk factors that can make one more susceptible to the defect. The disorder is generally more prevalent in males than in females and tends to occur earlier in males due to their involvement in more strenuous activities at a younger age. [8] In a young athlete, the spine is still growing; there are many ossification centers, leaving points of weakness in the spine. This leaves young athletes at increased risk, particularly when involved in repetitive hyperextension and rotation across the lumbar spine. [9] Spondylolysis is a common cause of low back pain in preadolescents and adolescent athletes, as it accounts for about 50% of all low back pain. [7] It is believed that both repetitive trauma and an inherent genetic weakness can make an individual more susceptible to spondylolysis. [4]

Risk factors

Sports involving repetitive or forceful hyperextension of the spine, especially when combined with rotation are the main mechanism of injury for spondylolysis. The stress fracture of the pars interarticularis occurs on the side opposite to activity. For instance, for a right-handed player, the fracture occurs on the left side of the vertebrae. [5]

Spondylolysis has a higher occurrence in the following activities: [5]

Although this condition can be caused by repetitive trauma to the lumbar spine in strenuous sports, other risk factors can also predispose individuals to spondylolysis. Males are more commonly affected by spondylolysis than females. [3] In one study looking at youth athletes, it was found that the mean age of individuals with spondylolisthesis was 20 years of age. [10] Spondylolysis also runs in families suggesting a hereditary component such as a predisposition to weaker vertebrae. [3]

Pathophysiology

Spondylolysis is a bony defect or fracture within the pars interarticularis of the vertebral arch in the spinal column. The vast majority of spondylolysis occur in the lumbar vertebrae, however it can also be seen in cervical vertebrae. [2] The lumbar vertebra consist of a body, pedicle, lamina, pars interarticularis, transverse process, spinous process and superior and inferior articular facets, which form joints that link the vertebrae together. When examining the vertebra, the pars interarticularis is the bony segment between the superior and inferior articular facet joints located anterior to the lamina and posterior to the pedicle. Separation of the pars interarticularis occurs when spondylolysis is present in the spinal column. [11]

Spondylolysis is typically caused by a stress fracture of the bone, and is especially common in adolescents who over-train in activities. The pars interarticularis is vulnerable to fracture during spinal hyperextension, especially when combined with rotation, or when experiencing a force during a landing. This stress fracture most commonly occurs where the concave lumbar spine transitions to the convex sacrum (L5-S1). A significant number of individuals with spondylolysis will develop spondylolisthesis, which is true for 50-81% of this population. [12] [3]

Pars interarticularis marked with red lines Spondylolysis- back pain.jpg
Pars interarticularis marked with red lines

Diagnosis

There are several imaging techniques used to diagnose spondylolysis. Common imaging techniques include X-ray, MRI, Bone Scintigraphy (Bone Scan), and Computed Tomography (CT Scan).[ citation needed ]

X-Ray

X-rays (electromagnetic radiation) are projected through the body to produce an image of its internal structures. The radiation is more attenuated (absorbed) by the denser tissues of the body (i.e. bone) than the softer tissues (i.e. muscles, organs, etc.) creating a picture composed of shades of grey ranging from white to black. A vertebra with a fracture or defect of the pars interarticularis will have a dark mark through this region of bone. Since this is difficult to see on the AP (anterior posterior) x-ray view an oblique x-ray of the lumbar spine can usually identify the spondylolysis. If inconclusive a further CT scan can produce a 3-dimensional images to more clearly show the defect although the exam increases the patients radiation dose by at least an order of magnitude than plain x-rays. [13] [14]

Bone scintigraphy

Bone scintigraphy showing black marks where pelvic bone damage has occurred. Scintigraphy pelvis with bone metastasis 01.jpg
Bone scintigraphy showing black marks where pelvic bone damage has occurred.

Also known as a bone scan, bone scintigraphy involves the injection of a small amount of radioactive tracer into the bloodstream. This tracer decays and emits radioactive energy which can be detected by a special camera. The camera produces a black and white image where areas shown as dark black indicate bone damage of some kind. If there is a black spot in the lumbar vertebrae (e.g. L5) this indicates damage and potentially spondylolysis. If this test is positive, a CT scan is usually ordered to confirm spondylolysis. [13]

Computed tomography

Cross-sectional image of a vertebra showing spondylolysis. 01-Spondylolyse L5S1 CT axial 001.jpg
Cross-sectional image of a vertebra showing spondylolysis.

Commonly known as a CT Scan or CAT scan, this form of imaging is very similar to x-ray technology but produces many more images than an x-ray does. The multiple images produce cross-sectional views not possible with an x-ray. This allows a physician or radiologist to examine the images from many more angles than an x-ray allows. For this reason the CT scan is much more accurate in detecting spondylolysis than an x-ray. Bone scintigraphy combined with CT scan is considered the gold standard which means that it is best at detecting spondylolysis. [13] [15]

MRI

MRI is a newer technique used to diagnose spondylolysis and is favorable for a few reasons. The MRI is much more accurate than the x-ray and also does not use radiation. The MRI uses powerful magnets and radio frequencies to produce very detailed images of many different densities of tissue including bone and soft tissues. [13] [16]

Treatment

Conservative management

Treatment for spondylolysis ranges from bracing, activity restriction, extension exercises, flexion exercises and deep abdominal strengthening, that is administered through physical therapy. The duration of physical therapy a patient receives varies upon the severity of spondylolysis, however typically ranges from three to six months. The goal of physical therapy is to minimize movement at the unstable defect of the pars interarticularis. Once a patient completes physical therapy, and displays no symptoms or inflammation in the lower back, they are cleared to continue with daily or athletic activities. However, a patient may need to maintain a variety of rehabilitation techniques after physical therapy to prevent the recurrence of spondylolysis. [17]

Deep abdominal co-contraction exercises

The aim of deep abdominal co-contraction exercises is to train muscles surrounding the lumbar spine which provide stability of the spine. Spondylolysis results in a spinal instability and disrupts patterns of co-recruitment between muscle synergies. Specifically, local muscles that attach directly to the spine are affected. The lumbar multifidus and transversus abdominis play a direct role in stabilizing the lumbar spine. Instead the local muscles in individuals with spondylolysis are vulnerable to dysfunction, which results in abnormal spinal stability causing chronic low back pain. To compensate, the large torque producing global muscles are used to stabilize the spine. [18]

In one study, patients are taught to train the co-contraction of deep abdominal muscles and lumbar multifidus in static postures, functional tasks and aerobic activities. This technique was shown to reduce pain and functional disability when compared to other conservative treatments. These results also had a long- term effect in reducing levels of pain and functional disability. This is because motor programming eventually became automatic, and conscious control was no longer needed to contract the deep abdominal muscles during activities. [18]

Activity restriction

Activity restriction of spondylolysis is advised for a short period of time once the patient becomes symptomatic, followed by a guided physical therapy program. Once spondylolysis has been diagnosed, treatment often consists of a short rest period of two to three days, followed by a physical therapy program. There should be restriction of heavy lifting, excessive bending, twisting and avoidance of any work, recreational activities or participation in sport that causes stress to the lumbar spine. [19] Activity restriction can help eliminate and control a patient's symptoms so they are able to resume their normal activities. [20] Activity restriction is most commonly used in conjunction with other rehabilitation techniques including bracing.[ citation needed ]

Bracing

Antilordotic lumbosacral brace (Boston brace) Kyphosis brace1.jpg
Antilordotic lumbosacral brace (Boston brace)

Acute spondylolysis is most commonly treated through the use of an antilordotic brace (Boston brace) to control and limit spinal movement, and reduce stress on the injured spinal segment. [19] [21] Bracing immobilizes the spine in a flexed position for a short period to allow healing of the bony defect in the pars interarticularis. [21] [22] An antilordotic brace commonly utilizes a plastic component that is contoured to closely fit the body. [21] Antilordotic bracing subsequently reduces the athlete's symptoms by decreasing the amount of stress on the low back, and allows a prompt return to sport for athletes. [19] Typically, bracing is utilized for 6–12 weeks. [22]

In order for a brace to be effective, it must be worn every day for the required amount of time. Patients are given a brace schedule determined by their physical therapist that explains the amount of time the brace must be worn daily. A brace's effectiveness increases with adherence to the bracing schedule. Patients that do not follow their bracing schedule are more likely to have their symptoms progress. [22] Research has demonstrated that when braces are used as prescribed with full compliance, they are successful at preventing spondylolysis progression. [19]

Surgery

Most patients with spondylolysis do not require surgery but, if the symptoms are not relieved with non-surgical treatments, or when the condition progresses to high grade spondylolisthesis, then patients may require surgery. There are two main types of surgery for this condition: [23]

Implications for rehabilitation

Spondylolysis can have a huge impact on a young athlete's career, and may impede their future ability to perform. [24] It is important to understand how social and psychological factors may affect rehabilitation of an injured athlete.

Frustration, anger, confusion, fear and depression are some of the psychological factors that injured athletes experience, therefore a debilitating injury can have a large impact on an athlete's mental well-being. [25] These psychological factors can also affect recovery and return to sport as fear of re-injury often prevents athletes from adhering to rehabilitation and returning to their sport at full intensity. [24]

Social factors can also impact the cognitive, behavioural and physical responses to injury. More specifically, social isolation from the team can have a profound psychological effect. This makes it essential to provide social support through supportive listening, emotional support, personal assistance, and reality conformation. [24]

It is also critical to educate the athletes on the rehabilitation process so they know what to expect. For instance, explaining what activities to avoid and will cause pain as well as the duration of the treatment process. In addition, it is important to select the correct treatment option for each individual. For conservative methods, adherence to the exercise requires motivated patients as it can be tedious and time-consuming. For instance, one study looking at deep abdominal co-contraction reported that it can take as long a 4–5 weeks to achieve this pattern of co-contraction.

Notable people with spondylolysis

Related Research Articles

<span class="mw-page-title-main">Lumbar vertebrae</span> Five vertebrae between the pelvis and the rib cage

The lumbar vertebrae are, in human anatomy, the five vertebrae between the rib cage and the pelvis. They are the largest segments of the vertebral column and are characterized by the absence of the foramen transversarium within the transverse process and by the absence of facets on the sides of the body. They are designated L1 to L5, starting at the top. The lumbar vertebrae help support the weight of the body, and permit movement.

<span class="mw-page-title-main">Kyphosis</span> Medical condition

Kyphosis is an abnormally excessive convex curvature of the spine as it occurs in the thoracic and sacral regions. Abnormal inward concave lordotic curving of the cervical and lumbar regions of the spine is called lordosis. It can result from degenerative disc disease; developmental abnormalities, most commonly Scheuermann's disease; Copenhagen disease, osteoporosis with compression fractures of the vertebra; multiple myeloma; or trauma. A normal thoracic spine extends from the 1st thoracic to the 12th thoracic vertebra and should have a slight kyphotic angle, ranging from 20° to 45°. When the "roundness" of the upper spine increases past 45° it is called kyphosis or "hyperkyphosis". Scheuermann's kyphosis is the most classic form of hyperkyphosis and is the result of wedged vertebrae that develop during adolescence. The cause is not currently known and the condition appears to be multifactorial and is seen more frequently in males than females.

<span class="mw-page-title-main">Lumbar spinal stenosis</span> Medical condition of the spine

Lumbar spinal stenosis (LSS) is a medical condition in which the spinal canal narrows and compresses the nerves and blood vessels at the level of the lumbar vertebrae. Spinal stenosis may also affect the cervical or thoracic region, in which case it is known as cervical spinal stenosis or thoracic spinal stenosis. Lumbar spinal stenosis can cause pain in the low back or buttocks, abnormal sensations, and the absence of sensation (numbness) in the legs, thighs, feet, or buttocks, or loss of bladder and bowel control.

<span class="mw-page-title-main">Back injury</span> Damage or wear to bones, muscles or other tissues of the back

Back injuries result from damage, wear, or trauma to the bones, muscles, or other tissues of the back. Common back injuries include sprains and strains, herniated discs, and fractured vertebrae. The lumbar spine is often the site of back pain. The area is susceptible because of its flexibility and the amount of body weight it regularly bears. It is estimated that low-back pain may affect as much as 80 to 90 percent of the general population in the United States.

<span class="mw-page-title-main">Spondylosis</span> Degeneration of the vertebral column

Spondylosis is the degeneration of the vertebral column from any cause. In the more narrow sense it refers to spinal osteoarthritis, the age-related degeneration of the spinal column, which is the most common cause of spondylosis. The degenerative process in osteoarthritis chiefly affects the vertebral bodies, the neural foramina and the facet joints. If severe, it may cause pressure on the spinal cord or nerve roots with subsequent sensory or motor disturbances, such as pain, paresthesia, imbalance, and muscle weakness in the limbs.

<span class="mw-page-title-main">Lordosis</span> Medical condition

Lordosis is historically defined as an abnormal inward curvature of the lumbar spine. However, the terms lordosis and lordotic are also used to refer to the normal inward curvature of the lumbar and cervical regions of the human spine. Similarly, kyphosis historically refers to abnormal convex curvature of the spine. The normal outward (convex) curvature in the thoracic and sacral regions is also termed kyphosis or kyphotic. The term comes from the Greek lordōsis, from lordos.

<span class="mw-page-title-main">Cervical fracture</span> Medical condition

A cervical fracture, commonly called a broken neck, is a fracture of any of the seven cervical vertebrae in the neck. Examples of common causes in humans are traffic collisions and diving into shallow water. Abnormal movement of neck bones or pieces of bone can cause a spinal cord injury, resulting in loss of sensation, paralysis, or usually death soon thereafter, primarily via compromising neurological supply to the respiratory muscles as well as innervation to the heart.

<span class="mw-page-title-main">Degenerative disc disease</span> Medical condition

Degenerative disc disease (DDD) is a medical condition typically brought on by the normal aging process in which there are anatomic changes and possibly a loss of function of one or more intervertebral discs of the spine. DDD can take place with or without symptoms, but is typically identified once symptoms arise. The root cause is thought to be loss of soluble proteins within the fluid contained in the disc with resultant reduction of the oncotic pressure, which in turn causes loss of fluid volume. Normal downward forces cause the affected disc to lose height, and the distance between vertebrae is reduced. The anulus fibrosus, the tough outer layers of a disc, also weakens. This loss of height causes laxity of the longitudinal ligaments, which may allow anterior, posterior, or lateral shifting of the vertebral bodies, causing facet joint malalignment and arthritis; scoliosis; cervical hyperlordosis; thoracic hyperkyphosis; lumbar hyperlordosis; narrowing of the space available for the spinal tract within the vertebra ; or narrowing of the space through which a spinal nerve exits with resultant inflammation and impingement of a spinal nerve, causing a radiculopathy.

<span class="mw-page-title-main">Spondylolisthesis</span> Displacement of one spinal vertebra compared to another

Spondylolisthesis is the displacement of one spinal vertebra compared to another. While some medical dictionaries define spondylolisthesis specifically as the forward or anterior displacement of a vertebra over the vertebra inferior to it, it is often defined in medical textbooks as displacement in any direction. Spondylolisthesis is graded based upon the degree of slippage of one vertebral body relative to the subsequent adjacent vertebral body. Spondylolisthesis is classified as one of the six major etiologies: degenerative, traumatic, dysplastic, isthmic, pathologic, or post-surgical. Spondylolisthesis most commonly occurs in the lumbar spine, primarily at the L5-S1 level, with the L5 vertebral body anteriorly translating over the S1 vertebral body.

<span class="mw-page-title-main">Back brace</span> Corrective medical device worn around a patients back

A back brace is a device designed to limit the motion of the spine in cases of bone fracture or in post-operative spinal fusiona, as well as a preventative measure against some progressive conditions or to correct patient posture.

<span class="mw-page-title-main">Traction (orthopedics)</span> Process for straightening broken bones

Traction is a set of mechanisms for straightening broken bones or relieving pressure on the spine and skeletal system. There are two types of traction: skin traction and skeletal traction. They are used in orthopedic medicine.

<span class="mw-page-title-main">Spinal fusion</span> Immobilization or ankylosis of two or more vertebrae by fusion of the vertebral bodies

Spinal fusion, also called spondylodesis or spondylosyndesis, is a neurosurgical or orthopedic surgical technique that joins two or more vertebrae. This procedure can be performed at any level in the spine and prevents any movement between the fused vertebrae. There are many types of spinal fusion and each technique involves using bone grafting—either from the patient (autograft), donor (allograft), or artificial bone substitutes—to help the bones heal together. Additional hardware is often used to hold the bones in place while the graft fuses the two vertebrae together. The placement of hardware can be guided by fluoroscopy, navigation systems, or robotics.

A burst fracture is a type of traumatic spinal injury in which a vertebra breaks from a high-energy axial load, with shards of vertebra penetrating surrounding tissues and sometimes the spinal canal. The burst fracture is categorized by the "severity of the deformity, the severity of (spinal) canal compromise, the degree of loss of vertebral body height, and the degree of neurologic deficit." Burst fractures are considered more severe than compression fractures because long-term neurological damage can follow. The neurologic deficits can reach their full extent immediately, or can progress for a prolonged time.

Copenhagen disease, sometimes known as Copenhagen syndrome or progressive non-infectious anterior vertebral fusion (PAVF), is a unique spinal disorder with distinctive radiological features. This is a rare childhood disease of unknown cause, affecting females slightly more than males (60%). Prevalence is unknown, but there have been approximately 80–100 individuals with Copenhagen disease reported since 1949. However, there is still little known research due to the rarity of the disease. The disease is so rare that the National Organization for Rare Diseases does not even mention Copenhagen disease in their database.

<span class="mw-page-title-main">Spinal disc herniation</span> Injury to the connective tissue between spinal vertebrae

A spinal disc herniation is an injury to the cushioning and connective tissue between vertebrae, usually caused by excessive strain or trauma to the spine. It may result in back pain, pain or sensation in different parts of the body, and physical disability. The most conclusive diagnostic tool for disc herniation is MRI, and treatment may range from painkillers to surgery. Protection from disc herniation is best provided by core strength and an awareness of body mechanics including posture.

<span class="mw-page-title-main">Vertebral compression fracture</span> Medical condition

A compression fracture is a collapse of a vertebra. It may be due to trauma or due to a weakening of the vertebra. This weakening is seen in patients with osteoporosis or osteogenesis imperfecta, lytic lesions from metastatic or primary tumors, or infection. In healthy patients, it is most often seen in individuals suffering extreme vertical shocks, such as ejecting from an ejection seat. Seen in lateral views in plain x-ray films, compression fractures of the spine characteristically appear as wedge deformities, with greater loss of height anteriorly than posteriorly and intact pedicles in the anteroposterior view.

<span class="mw-page-title-main">Laminotomy</span> Surgical procedure

A laminotomy is an orthopaedic neurosurgical procedure that removes part of the lamina of a vertebral arch in order to relieve pressure in the vertebral canal. A laminotomy is less invasive than conventional vertebral column surgery techniques, such as laminectomy because it leaves more ligaments and muscles attached to the spinous process intact and it requires removing less bone from the vertebra. As a result, laminotomies typically have a faster recovery time and result in fewer postoperative complications. Nevertheless, possible risks can occur during or after the procedure like infection, hematomas, and dural tears. Laminotomies are commonly performed as treatment for lumbar spinal stenosis and herniated disks. MRI and CT scans are often used pre- and post surgery to determine if the procedure was successful.

<span class="mw-page-title-main">Facet syndrome</span> Medical condition

Facet syndrome is a syndrome in which the facet joints cause painful symptoms. In conjunction with degenerative disc disease, a distinct but functionally related condition, facet arthropathy is believed to be one of the most common causes of lower back pain.

<span class="mw-page-title-main">Spinal stenosis</span> Disease of the bony spine that results in narrowing of the spinal canal

Spinal stenosis is an abnormal narrowing of the spinal canal or neural foramen that results in pressure on the spinal cord or nerve roots. Symptoms may include pain, numbness, or weakness in the arms or legs. Symptoms are typically gradual in onset and improve with leaning forward. Severe symptoms may include loss of bladder control, loss of bowel control, or sexual dysfunction.

Cervical spondylotic myelopathy (CSM) is a disorder characterised by the age-related deterioration of the cervical spinal cord. Also called spondylotic radiculomyelopathy (SRM), it is a neurological disorder related to the spinal cord and nerve roots. The severity of CSM is most commonly associated with factors including age, location and extent of spinal cord compression.

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