Radiculopathy | |
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C5-C6, followed by C6-C7, is the most common location for radiculopathy in the neck. | |
Specialty | Neurosurgery |
Radiculopathy, also commonly referred to as pinched nerve, refers to a set of conditions in which one or more nerves are affected and do not work properly (a neuropathy). Radiculopathy can result in pain (radicular pain), weakness, altered sensation (paresthesia) or difficulty controlling specific muscles. [1] Pinched nerves arise when surrounding bone or tissue, such as cartilage, muscles or tendons, put pressure on the nerve and disrupt its function. [2]
In a radiculopathy, the problem occurs at or near the root of the nerve, shortly after its exit from the spinal cord. However, the pain or other symptoms often radiate to the part of the body served by that nerve. For example, a nerve root impingement in the neck can produce pain and weakness in the forearm. Likewise, an impingement in the lower back or lumbar-sacral spine can be manifested with symptoms in the foot.
The radicular pain that results from a radiculopathy should not be confused with referred pain, which is different both in mechanism and clinical features. Polyradiculopathy refers to the condition where more than one spinal nerve root is affected.
Radiculopathy most often is caused by mechanical compression of a nerve root usually at the exit foramen or lateral recess. It may be secondary to intervertebral disk herniation (most commonly at C7 and then the C6 level), degenerative disc disease, osteoarthritis, facet joint degeneration/hypertrophy, ligamentous hypertrophy, spondylolisthesis, or a combination of these factors. [3] [4] Other possible causes of radiculopathy include neoplastic disease, infections such as shingles, HIV, or Lyme disease, spinal epidural abscess, spinal epidural hematoma, proximal diabetic neuropathy, Tarlov cysts, or, more rarely, sarcoidosis, arachnoiditis, tethered spinal cord syndrome, or transverse myelitis. [3] [ verification needed ]
Repeated, longer term exposure (5 years or more) to certain work-related activities may put people at risk of developing lumbosacral radiculopathy. [5] These behaviours may include physically demanding work, bending over or twisting at the trunk, lifting and carrying, or a combination of these activities. [5]
Less common causes of radiculopathy include injury caused by tumor (which can compress nerve roots locally) and diabetes (which can effectively cause ischemia or lack of blood flow to nerves).[ medical citation needed ]
Signs and Symptoms
Radiculopathy is a diagnosis commonly made by physicians in primary care specialties, orthopedics, physiatry, and neurology. The diagnosis may be suggested by symptoms of pain, numbness, paresthesia, and weakness in a pattern consistent with the distribution of a particular nerve root, such as sciatica. [6] [7] Neck pain or back pain may also be present.[ medical citation needed ] Physical examination may reveal motor and sensory deficits in the distribution of a nerve root. In the case of cervical radiculopathy , Spurling's test may elicit or reproduce symptoms radiating down the arm. Similarly, in the case of lumbosacral radiculopathy, a straight leg raise maneuver or a femoral nerve stretch test may demonstrate radiculopathic symptoms down the leg. [3] Deep tendon reflexes (also known as a Stretch reflex) may be diminished or absent in areas innervated by a particular nerve root.[ citation needed ]
Diagnosis typically involves electromyography and lumbar puncture. [3] Shingles is more common among the elderly and immunocompromised; usually (but not always) pain is followed by appearance of a rash with small blisters along a single dermatome. [3] It can be confirmed by quick laboratory tests. [8] Acute Lyme radiculopathy follows a history of outdoor activities during warmer months in likely tick habitats in the previous 1–12 weeks. [9] In the U.S., Lyme is most common in New England and Mid-Atlantic states and parts of Wisconsin and Minnesota, but it is expanding to other areas. [10] [11] The first manifestation is usually an expanding rash possibly accompanied by flu-like symptoms. Lyme radiculopathy is usually worse at night and accompanied by extreme sleep disturbance, lymphocytic meningitis with variable headache and no fever, and sometimes by facial palsy or Lyme carditis. [12] Lyme can also cause a milder, chronic radiculopathy an average of 8 months after the acute illness. [3] Lyme can be confirmed by blood antibody tests and possibly lumbar puncture. [9] [3] If present, the above conditions should be treated immediately. [3]
Although most cases of radiculopathy are compressive and resolve with conservative treatment within 4–6 weeks, guidelines for managing radiculopathy recommend first excluding possible causes that, although rare, require immediate attention, among them the following. Cauda equina syndrome should be investigated in case of saddle anesthesia, loss of bladder or bowel control, or leg weakness. [3] Cancer should be suspected if there is previous history of cancer, unexplained weight loss, or low-back pain that does not decrease by lying down or is unremitting. [3] Spinal epidural abscess is more common among those with diabetes mellitus or immunocompromised, who use intravenous drugs, or had spinal surgery, injection or catheter; it typically causes fever, leukocytosis and increased erythrocyte sedimentation rate. [3] If any of the previous is suspected, urgent magnetic resonance imaging is recommended for confirmation. [3] Proximal diabetic neuropathy typically affects middle aged and older people with well-controlled type-2 diabetes mellitus; onset is sudden causing pain usually in multiple dermatomes quickly followed by weakness.[ citation needed ]
Investigations
If symptoms do not improve after 4–6 weeks of conservative treatment, or the person is more than 50 years old, further tests are recommended. [3] The American College of Radiology recommends that projectional radiography is the most appropriate initial study in all patients with chronic neck pain. [13] Two additional diagnostic tests that may be of use are magnetic resonance imaging and electrodiagnostic testing. Magnetic resonance imaging (MRI) of the portion of the spine where radiculopathy is suspected may reveal evidence of degenerative change, arthritic disease, or another explanatory lesion responsible for the patient's symptoms. Electrodiagnostic testing, consisting of NCS (nerve conduction study) and EMG (electromyography), is also a powerful diagnostic tool that may show nerve root injury in suspected areas. On nerve conduction studies, the pattern of diminished Compound muscle action potential and normal sensory nerve action potential may be seen given that the lesion is proximal to the posterior root ganglion. Needle EMG is the more sensitive portion of the test, and may reveal active denervation in the distribution of the involved nerve root, and neurogenic-appearing voluntary motor units in more chronic radiculopathies. Given the key role of electrodiagnostic testing in the diagnosis of acute and chronic radiculopathies, the American Association of Neuromuscular & Electrodiagnostic Medicine has issued evidence-based practice guidelines, for the diagnosis of both cervical and lumbosacral radiculopathies. [14] [15] The American Association of Neuromuscular & Electrodiagnostic Medicine has also participated in the Choosing Wisely Campaign and several of their recommendations relate to what tests are unnecessary for neck and back pain. [16]
Ideally, effective treatment aims to resolve the underlying cause and restores the nerve root to normal function. Conservative treatment may include bed rest, physical therapy, or simply continuing to do usual activities; for pain, nonsteroidal anti-inflammatory drugs, nonopioid or, in some cases, narcotic analgesics may be prescribed. [3] A systematic review found moderate quality evidence that spinal manipulation is effective for the treatment of acute lumbar radiculopathy [17] and cervical radiculopathy. [18] Only low level evidence was found to support spinal manipulation for the treatment of chronic lumbar radiculopathies, and no evidence was found to exist for treatment of thoracic radiculopathy. [17] Evidence also supports consideration of epidural steroid injection with local anesthetic in improving both pain and function in cases of lumbosacral radiculopathy. [19]
With a recent injury (e.g. one that occurred one week ago), a formal physical therapy referral is not yet indicated. Often mild to moderate injuries will resolve or greatly improve within the first few weeks. Additionally, patients with acute injuries are often too sore to participate effectively in physical therapy so soon after the insult. Waiting two to three weeks is generally recommended before starting formal physical therapy. In acute injury resulting in lumbosacral radiculopathy, conservative treatment such as acetaminophen and NSAIDs should be the first line of therapy. [1]
Therapeutic exercises are frequently used in combination with many of the previously mentioned modalities and with great results. A variety of exercise regimens are available in patient treatment. An exercise regimen should be modified according to the abilities and weaknesses of the patient. [20] Stabilization of the cervicothoracic region is helpful in limiting pain and preventing re-injury. Cervical and lumbar support braces typically are not indicated for radiculopathy, and may lead to weakness of support musculature. [21] The first part of the stabilization procedure is achieving a pain free full range of motion which can be accomplished through stretching exercises. Subsequently, a strengthening exercise program should be designed to restore the deconditioned cervical, shoulder girdle, and upper trunk musculature. [22] As reliance on the neck brace diminishes, an isometric exercise regimen should be introduced.[ medical citation needed ] This is a preferred method of exercise during the sub-acute phase because it resists atrophy and is least likely to exacerbate the condition. Single plane resistance exercises against cervical flexion, extension, bending, and rotation are used.[ citation needed ]
While conservative approaches for rehabilitation are ideal, some patients will not improve and surgery is still an option. [23] Patients with large cervical disk bulges may be recommended for surgery; however, most often, conservative management will help the herniation regress naturally. [24] Procedures such as foraminotomy, laminotomy, or discectomy may be considered by neurosurgeons and orthopedic surgeons. Regarding surgical interventions for cervical radiculopathy, the anterior cervical discectomy and fusion procedure is more commonly performed than the posterior cervical foraminotomy procedure. [25] However, both procedures are likely equally effective and without significant differences in their complication rates. [25]
Cervical radiculopathy has an annual incidence rate of 107.3 per 100,000 for men and 63.5 per 100,000 for women, whereas lumbar radiculopathy has a prevalence of approximately 3-5% of the population. [26] [27] According to the AHRQ's 2010 National Statistics for cervical radiculopathy, the most affected age group is between 45 and 64 years with 51.03% of incidents.[ citation needed ] Females are affected more frequently than males and account for 53.69% of cases. Private insurance was the payer in 41.69% of the incidents followed by Medicare with 38.81%. In 71.61% of cases the patients' income was considered not low for their zipcode. Additionally over 50% of patients lived in large metropolitans (inner city or suburb). The South is the most severely affected region in the US with 39.27% of cases. According to a study performed in Minnesota, the most common manifestation of this set of conditions is the C7 monoradiculopathy, followed by C6. [28]
Transverse myelitis (TM) is a rare neurological condition wherein the spinal cord is inflamed. The adjective transverse implies that the spinal inflammation (myelitis) extends horizontally throughout the cross section of the spinal cord; the terms partial transverse myelitis and partial myelitis are sometimes used to specify inflammation that affects only part of the width of the spinal cord. TM is characterized by weakness and numbness of the limbs, deficits in sensation and motor skills, dysfunctional urethral and anal sphincter activities, and dysfunction of the autonomic nervous system that can lead to episodes of high blood pressure. Signs and symptoms vary according to the affected level of the spinal cord. The underlying cause of TM is unknown. The spinal cord inflammation seen in TM has been associated with various infections, immune system disorders, or damage to nerve fibers, by loss of myelin. As opposed to leukomyelitis which affects only the white matter, it affects the entire cross-section of the spinal cord. Decreased electrical conductivity in the nervous system can result.
Back pain is pain felt in the back. It may be classified as neck pain (cervical), middle back pain (thoracic), lower back pain (lumbar) or coccydynia based on the segment affected. The lumbar area is the most common area affected. An episode of back pain may be acute, subacute or chronic depending on the duration. The pain may be characterized as a dull ache, shooting or piercing pain or a burning sensation. Discomfort can radiate to the arms and hands as well as the legs or feet, and may include numbness or weakness in the legs and arms.
Sciatica is pain going down the leg from the lower back. This pain may go down the back, outside, or front of the leg. Onset is often sudden following activities like heavy lifting, though gradual onset may also occur. The pain is often described as shooting. Typically, symptoms are only on one side of the body. Certain causes, however, may result in pain on both sides. Lower back pain is sometimes present. Weakness or numbness may occur in various parts of the affected leg and foot.
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.
Cervical spine disorders are illnesses that affect the cervical spine, which is made up of the upper first seven vertebrae, encasing and shielding the spinal cord. This fragment of the spine starts from the region above the shoulder blades and ends by supporting and connecting the skull.
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.
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.
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.
Cauda equina syndrome (CES) is a condition that occurs when the bundle of nerves below the end of the spinal cord known as the cauda equina is damaged. Signs and symptoms include low back pain, pain that radiates down the leg, numbness around the anus, and loss of bowel or bladder control. Onset may be rapid or gradual.
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.
A nerve root is the initial segment of a nerve leaving the central nervous system. Nerve roots can be classified as:
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.
Cervical spinal stenosis is a bone disease involving the narrowing of the spinal canal at the level of the neck. It is frequently due to chronic degeneration, but may also be congenital. Treatment is frequently surgical.
Neurogenic claudication (NC), also known as pseudoclaudication, is the most common symptom of lumbar spinal stenosis (LSS) and describes intermittent leg pain from impingement of the nerves emanating from the spinal cord. Neurogenic means that the problem originates within the nervous system. Claudication, from the Latin word for to limp, refers to painful cramping or weakness in the legs. NC should therefore be distinguished from vascular claudication, which stems from a circulatory problem rather than a neural one.
The Spurling test is a medical maneuver used to assess nerve root pain. The patient rotates their head to the affected side and extends their neck, while the examiners applies downward pressure to the top of the patient's head. A positive Spurling's sign is when the pain arising in the neck radiates in the direction of the corresponding dermatome ipsilaterally. It is a type of cervical compression test.
Plexopathy is a disorder of the network of nerves in the brachial or lumbosacral plexus. Symptoms include pain, muscle weakness, and sensory deficits (numbness).
Tarlov cysts, are type II innervated meningeal cysts, cerebrospinal-fluid-filled (CSF) sacs most frequently located in the spinal canal of the sacral region of the spinal cord (S1–S5) and much less often in the cervical, thoracic or lumbar spine. They can be distinguished from other meningeal cysts by their nerve-fiber-filled walls. Tarlov cysts are defined as cysts formed within the nerve-root sheath at the dorsal root ganglion. The etiology of these cysts is not well understood; some current theories explaining this phenomenon have not yet been tested or challenged but include increased pressure in CSF, filling of congenital cysts with one-way valves, inflammation in response to trauma and disease. They are named for American neurosurgeon Isadore Tarlov, who described them in 1938.
A disc protrusion is a medical condition that can occur in some vertebrates, including humans, in which the outermost layers of the anulus fibrosus of the intervertebral discs of the spine are intact but bulge when one or more of the discs are under pressure.
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.