Spinal Column - Cleveland Clinic
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Spinal Column - Cleveland Clinic
SPRING 2007 Spinal Column This Issue: The Cervical Spine In This Issue: Conservative Treatment of Neck Pain Minimally Invasive Cervical Laminoforaminotomy Treating Cervical Radiculopathy and Myelopathy Cervical Disc Arthroplasty Cervical Deformities Cervical Spine Tumors p. 2 p. 4 p. 6 p. 8 p. 10 p. 12 A Look at the Cervical Spine A message from Edward C. Benzel, M.D. This issue of Spinal Column focuses on cervical spine pathologies and treatment strategies. Dr. Mroz has collected and collated a wonderful mix of papers addressing the variety of pathologies and treatment opportunities available. This includes conservative, operative and minimally invasive treatments for a variety of conditions. Pathologies of the cervical spine pose the potential for greater risk to patients than similar analogous pathologies in the lumbar spine, due to the heightened potential for spinal cord injury and greater chance of injury to visceral structures. Therefore, the use of less risky diagnostic and treatment strategies are emphasized; conservative treatment, if effective, is always preferred. Dr. Zachary analyzes such conservative treatments on page 2. When surgery is required, minimally invasive techniques, when an option, are beneficial. Dr. Steinmetz reviews the use of such techniques for a laminoforaminotomy on page 4. The most common cause of cervical spine radiculopathy and myelopathy is degenerative spine disease. The ‘disease’ part of ‘degenerative spine disease’ is really a misnomer. It, in reality, is not a disease at all, but a manifestation of the natural process of aging. The intervertebral discs bulge and the facet joints and ligaments hypertrophy, which causes encroachment on the spinal canal and neuroforamina with spinal cord and nerve root distortion and compression. Surgical strategies designed to relieve neural compression or to stabilize the spine have, therefore, been devised. Both open and, when appropriate, minimally invasive operations can be used to treat affected patients. Dr. Bell reviews treatment options for both radiculopathy and myelopathy on page 6. An early-stage manifestation of cervical spine degenerative disease is that of disc herniation. Disc herniation and the resultant radiculopathy and/or myelopathy can be treated surgically. Anterior cervical discectomy is usually followed by fusion (anterior cervical discectomy and fusion). This has been shown to be a very successful operation over the years. Recently, the substitution of an artificial disc for the fusion part of the operation has been used as a strategy to stabilize the spine and to retain segmental motion following the removal of the disc. Dr. Mroz considers its usage in his article on page 8. I hope you enjoy this collection of well-illustrated articles and that they provide insight into this interesting and perhaps most misunderstood aspect of spine care. An end-stage manifestation of cervical spine degenerative disease is spine deformation, the most common of which is kyphosis. Contributing factors to the development of a kyphotic deformity are the degenerative (aging) process itself, often combined with superimposed, prior spine surgery. The destabilizing effects of an unsuccessful continued on page 14 Edward C. Benzel, M.D. For more information, please contact Dr. Benzel at 216.445.5514 or our administrator, Kathy Huffman, at 216.445.8442. To refer patients, call 216.445.2225 or 800.553.5056, ext. 42225. Conservative Treatment of Neck Pain By Adrian Zachary, D.O., M.P.H. Neck pain is a prevalent and at times debilitating problem. Although not as common as low back pain, 40 to 70 percent of the general population will experience cervical spine pain at some point in their lives1,2 and up to 10 percent of adults will suffer from a disabling neck problem.3 Adrian Zachary, D.O., M.P.H. Dr. Zachary can be reached at 216.445.5061 or zachara@ccf.org. Most cases of cervical spine pain present spontaneously and resolve within days to weeks with little or no treatment. Some risk factors for developing cervical spine pain include a history of headaches or low back pain, whiplash injury, high quantitative job demands and low coworker support. Studies suggest cervical trauma or whiplash injury increases the likelihood of patients developing chronic cervical pain; however, in some cases litigation and monetary gain may be a confounding factor influencing the duration of pain in this population. What are the best treatment options for patients suffering from neck pain? With evolving fields in complementary medicine and alternative treatment modalities, many physicians are left in a quandary as how to best treat their patients. This article offers an overview of many cervical treatment modalities. Diagnosing the Problem The key to treating cervical spine pain is a thorough history and examination. Most cases of neck pain are benign, but neck pain can be the presenting symptom of more serious pathology and therefore requires an accurate history. Recent trauma, neurologic deficits, radicular symptoms, bowel or bladder dysfunction, a history of malignancy, night pain or fevers should heighten the examiner’s suspicion for further work up. Likewise, examination should focus on identifying neurologic deficits, gait dysfunction, upper motor neuron signs or restricted cervical range of motion. In the absence of neurologic deficits, radicular symptoms and ominous red flags, treatment for cervical pain and whiplash injuries should be conservative. Trauma patients will usually have cervical x-rays or a CT scan in the acute setting. Evaluation for fracture or instability is appropriate but extensive evaluation is not indicated in the absence of neurologic deficits. In the office setting, an x-ray is appropriate but usually of low yield at the initial onset of pain. The use of MRI should be reserved for patients with neurologic deficits, symptoms suggestive of more serious pathology or patients who do not respond to conservative treatment. The use of non-steroidal anti-inflammatories (NSAIDs), ice/heat, avoidance of aggravating activities and analgesics should be the first line of treatment for cervical spine pain. Short-term use of a soft collar may Spinal Column | SPRING 2007 be employed, but prolonged use should be discouraged. Studies have shown that two weeks of cervical collar use was no more effective at relieving pain than two days of use. Pharmacologic Treatments For mild pain, the use of NSAIDs or acetaminophen is recommended. However, high doses of acetaminophen can lead to hepatotoxicity and chronic NSAID use can cause serious gastrointestinal side effects. Therefore, close monitoring is indicated with the use of these medications. Opioid treatment is appropriate for acute cervical pain, but should be monitored closely for effectiveness and side effects. Prolonged use of opiate analgesics increases the risk of tolerance and dependence. Much debate surrounds the use of opiate analgesics for chronic neck pain, but studies suggest the risk for significant abuse is highest in patients with a prior addiction, further emphasizing the importance of a thorough past medical history. The use of muscle relaxants appears to be effective in reducing cervical pain, decreasing muscle spasm and improving sleep. Muscle relaxants are more effective in the early course of treatment, suggesting a shorter course of these medications is preferable. Side-effects of drowsiness, dry mouth, nausea and vomiting are common and, at times, limit the use of these medications. Tricyclic antidepressants have not been well studied in the treatment of acute or chronic cervical spine pain. Although commonly prescribed for whiplash injuries and cervical radiculopathy, oral corticosteroids have not been well studied in neck pain. Literature suggests that a short course of steroids may provide overall reduction in pain, in analgesic usage and in number of sick days. Physical Therapy and Manual Medicine Physical therapy has long been the standard in the treatment of neck pain. Literature reviews seem to suggest moderate evidence that physical therapy is effective in decreasing pain from acute whiplash injuries4. Well-designed, controlled studies, however, are also lacking for this treatment. There is evidence that an early return to regular activities may be equally effective at alleviating cervical pain. Cleveland CLinic An increasing number of patients suffering from cervical pain are pursuing manual medical treatments from chiropractors, physiotherapists and osteopathic physicians. There is conflicting evidence regarding the efficacy of these modalities. Recent reviews of manipulative therapy for pain control have failed to report convincing evidence of its effectiveness in acute or chronic neck pain, most reporting lack of welldesigned studies. There is moderate evidence that manipulation in combination with physical therapy is more beneficial than manipulation alone, but not more effective than conventional exercise treatment for neck pain. Modalities and Interventional Treatments Cervical facet joint and medial branch blocks appear to be effective in the shortterm treatment of cervical spine pain. Recent studies suggest there is evidence that cervical medial branch radiofrequency ablation is an effective cervical pain treatment with longer duration of action than medial branch blocks in whiplash patients who have failed other forms of conservative treatment.5,6 Cervical traction is often employed in the treatment of neck pain. Recent reviews suggest a lack of conclusive evidence to support the efficacy of continuous traction in the treatment of cervical spine pain, but there is moderate evidence to support the use of intermittent traction over continuous traction. There is strong support in the medical community for the use of conservative therapeutic options in the treatment of acute and chronic cervical spine pain versus early surgical intervention. The use of electrotherapies, including TENS, pulsed electromagnetic field therapy and electrical muscle stimulation with physical therapy, has been an essential part of cervical rehabilitation. Strong evidence supporting the effectiveness of these therapies, however, is unfortunately lacking. There is conflicting evidence regarding the effectiveness of acupuncture in the treatment of cervical spine pain. A recently published report shows moderate evidence supporting acupuncture as being superior to massage and some other alternative therapies in the treatment of cervical spine pain. However, other studies suggest a lack of strong supporting evidence of the effectiveness of acupuncture in the treatment of neck pain. The effectiveness of Botox injections in subjects suffering with chronic mechanical neck pain has not been shown to be any more effective than saline injections in several high-quality studies. Patient education is an important component of an effective treatment plan for cervical spine pain. Educating patients regarding the benign nature of most neck pain decreases the incidence of chronic pain complaints in whiplash-injured patients. Fear of the underlying cause of pain has been shown to be a barrier to recovery for many patients. Education also may help in a patient’s ability to actively cope with neck pain. Studies have shown that passive coping is a strong predictor of patients developing disabling neck pain. Despite the paucity of quality research validating the use of commonly prescribed modalities, there is strong support in the medical community for the use of conservative therapeutic options in the treatment of acute and chronic cervical spine pain versus early surgical intervention. However, patients with severe disability, neurologic deficits or neck pain recalcitrant to conservative treatment should be referred to a spine specialist for surgical evaluation. 1C ote P, Cassidy JD, Carroll L. Saskatchewan health and back pain survey: the prevalence of neck pain and related disability in Saskatchewan adults. Spine. 1998; 23:1 1689-1698. 2L evin KH, Covington EC, Devereaux MW, et al. Neck pain and low back pain. Continuum. (NY) 2001; 7:1-205. 3B ovim G, Schrader H, Sand T. Neck pain in the general population. Spine. 1994;19:1307-1309. 4S arig-Bahat H. Evidence for exercise therapy in mechanical neck disorders. Man Ther. 2003;8:10-20. 5B ogduk N. Treatment of whiplash injuries. Spine: State of the Art Reviews. 1998;12:469-83. 6 Niemisto L, et al. Radiofrequency denervation for neck and back pain: a systemic review within the framework of the Cochran Collaboration Back Review Group. Spine 2003;28(16):1877-1888. 7T rinh KV et al. Acupuncture for neck disorders. Cochrane Database Syst Rev. 2006;3:CD004870. Adrian Zachary, D.O., M.P.H., is a staff medical spine specialist with Cleveland Clinic. He specializes in interventional pain management and non-surgical treatment of spine disorders. clevelandclinic.org/spine Minimally Invasive Cervical Laminoforaminotomy By Michael P. Steinmetz, M.D. Posterior cervical decompression is very successful at relieving pain and neurologic dysfunction related to stenosis of one to a few neural foramen. It was first proposed by Spurling and Scoville in the 1940s and is a procedure of choice for posterolateral disc herniations and focal foraminal stenosis. It also is useful for those patients in which an anterior approach would be contraindicated. Michael P. Steinmetz, M.D. Dr. Steinmetz can be reached at 216.445.4633 or steinmm@ccf.org. In general, surgery consists of creating a small window in the bone of the dorsal cervical spine — that is, the lamina and facet joint. This procedure is commonly referred to as a laminoforaminotomy. The classic open posterior cervical approach necessitates a moderatesized midline incision, lateral reflection of the upper cervical musculature and exposure of the medial facet and lamina. Extensive muscle dissection is often required, which frequently results in considerable neck pain and spasticity following surgery. Moreover, a large visible scar is often left following surgery. Minimally invasive techniques, however, allow the surgeon to perform the laminoforaminotomy without the need for extensive muscle dissection or a large incision. The success rate of the procedure is approximately 90 percent, and the incidence of complications is low. Following surgery, the patient is left with an approximately 2 cm incision and may return to activity as soon as tolerated; no fusion is required. The procedure is ideal for a lateral soft disc herniation or lateral spondylosis resulting in foraminal stenosis and radiculopathy (Figure 1). The procedure is not used for central stenosis due to a midline disc herniation or bulge or to treat cervical myelopathy. It also may not be appropriate for multi-level foraminal stenosis, but may be utilized for bilateral disease. Spinal Column | SPRING 2007 The patient is positioned either prone or sitting. Lateral and/or AP fluoroscopy is used to localize the appropriate level (Figure 2). The incision is based over the level to be decompressed and is approximately one finger breadth lateral to the midline (approximately 2 cm). The size of the incision depends on the size of the tube used. An 18 mm tube or, alternatively, a 16 or 14 mm tube, may be utilized. An incision of approximately 20 mm is made and a series of dilators are delivered through the incision until the working diameter is reached and the final working tube is placed (Figure 3). A surgical microscope is then used to clear muscle and tissue off the interior edge of the lamina and medial facet. A small window of bone is drilled away with a high-speed drill and cleared with fine curettes or punches. This is done to relieve the exiting nerve root of any compression (Figure 4). The tube is removed and the skin is closed with fine sutures (under the skin) and glue (Figure 5). The success rate of the procedure is approximately 90 percent, and the incidence of complications is low. Following surgery, the patient is left with an approximately 2 cm incision and may return to activity as soon as tolerated; no fusion is required. Recently, advances in this approach have afforded the ability to perform instrumented fusion in the dorsal cervical spine. Alterations are currently being performed in the instrumentation sets to make this much easier. Overall, minimally invasive laminoforaminotomy is a very successful operation for the carefully selected patient. Michael P. Steinmetz, M.D., is an assistant professor of surgery with Cleveland Clinic. His clinical interests include minimally invasive spine surgery, including decompression and fusion; spine and spinal cord tumors; adult reconstructive surgery; and adult deformity surgery. He maintains an active laboratory investigating spinal cord injury, regeneration and plasticity. Cleveland CLinic Figure 1 Figure 4 Figure 2 Figure 5 Figure 1: Axial MRI of the spine at the C5/6 level. A left-side far lateral disc herniation is present with resultant foraminal stenosis. Figure 2: Lateral fluoroscopy is used to localize the appropriate level to decompress. Figure 3: A series of dilators are used to place the working tube. The tube is attached to the operating room bed rigidly. Figure 4: The foraminotomy is performed under the operating room microscope. The decompression is finished when a small nerve hook may be passed through the foramen with no obstruction. Figure 5: The incision may be closed with sutures and glue. Figure 3 clevelandclinic.org/spine Treating Cervical Radiculopathy and Myelopathy By Gordon R. Bell, M.D. Figure 1: Axial T2 MRI showing a right lateral disc herniation at C5-6, which was removed by a posterior laminotomy and discectomy. Two spinal conditions frequently encountered in clinical practice are cervical radiculopathy and cervical myelopathy. Cervical radiculopathy refers to radiating arm pain with or without sensory and/or motor loss. Cervical myelopathy, on the other hand, presents a complex — and sometimes confusing — upper motor neuron clinical picture characterized by symptoms and signs of spinal cord compression. Occasionally both lower motor nerve root findings and spinal cord upper motor neuron findings may co-exist (myeloradiculopathy), which may further complicate the clinical presentation. The natural history, clinical presentation and expected outcome of cervical radiculopathy and cervical myelopathy are very different; surgical treatment of each is therefore different. While radiculopathy generally is treated by anterior decompression and fusion (unless a far lateral herniation or foraminal stenosis exists), cervical myelopathy can be treated either by anterior decompression and fusion or by posterior decompression and stabilization, depending upon the alignment of the cervical spine. Cervical Radiculopathy Radiating arm pain is commonly due to nerve root compression from disc herniation or foraminal stenosis. The diagnosis is made by correlating the dermatomal distribution of the pain with objective neurological findings and corroborative imaging, either by magnetic resonance imaging (MRI) or by myelography with computed tomography (CT). Many, if not most, patients with cervical radiculopathy will get better without surgery. The absolute indications for surgery include progressive arm weakness or findings suggesting concomitant spinal cord compression (myelopathy). The most common indication for surgery is intractable arm pain that has failed to respond to conservative measures. Conservative treatment includes anti-inflammatories, analgesics and physical therapy, which includes a McKenzie neck program and passive modalities such as cervical traction. Figure 2a Surgery for cervical radiculopathy is most commonly performed anteriorly and usually involves an anterior cervical discectomy and fusion (ACDF), in which the disc is removed, the nerve root is decompressed and a fusion is performed. This procedure was originally described in the early 1950s. Fusion involves the use of bone and sometimes an interbody device to augment the fusion. The bone graft may be a tricortical iliac crest graft taken from the patient (autologous graft), or it may be cadaveric bone commercially obtained from a bone bank (allograft). Interbody devices, made from either titanium or carbon, and filled with cancellous bone graft, also may be used. The bone graft or interbody device commonly is held in position by a small anterior plate, although a single-level fusion may be performed with bone graft only and without a plate. Occasionally, a far lateral disc herniation with resultant radiculopathy can be removed posteriorly without performing a fusion (Figure 1). This situation is uncommon but, when present, offers the opportunity for nerve root decompression without fusion. Radiculopathy from foraminal stenosis also can be treated with posterior foraminal decompression alone. Figure 2b Figure 2a: Sagittal cervical MRI showing severe cord compression at C4-5 and C5-6. Note the severe narrowing with loss of the white cerebrospinal fluid surrounding the spinal cord at these levels. Figure 2b: Post-operative lateral x-ray showing five small laminoplasty plates from C3-7 that keep the spinal canal hinged open at the decompressed levels. Relief of arm pain following an anterior fusion is reliable and predictable. Good or excellent results are reported in approximately 85 to 90 percent of patients. Complications are relatively uncommon and can include nerve root injury, pseudarthrosis, transient airway obstruction (from laryngospasm, hematoma, vocal cord paralysis, allergic reaction or edema), hoarseness (from retraction or injury to the superior or recurrent laryngeal nerve), and dysphagia (from retraction Spinal Column | SPRING 2007 Cleveland CLinic of the esophagus). Dysphagia is more common with multilevel decompression and prolonged surgery. Less common complications include nerve root injury, spinal cord injury and vascular injury. Cervical Myelopathy kyphosis. The ability of posterior surgery to adequately decompress the spine depends upon the presence of preoperative cervical lordosis or neutral alignment. With a lordotic or neutral spine, the spinal cord can “drift” posteriorly following the posterior decompression, thereby relieving the cord compression. Spinal cord compression commonly occurs from a congenitally narrowed canal, from degenerative changes or a combination of both. This may result in a confusing clinical picture with symptoms and signs of spinal cord dysfunction, nerve root compression or both. When due to age-related canal narrowing, the condition is referred to as cervical spondylotic myelopathy (CSM). The posterior decompressive options include laminectomy and fusion or laminoplasty, in which the spinal canal is enlarged by “hinging” open the laminae without actually removing them (Figure 2). This offers the dual advantages of enlarging and decompressing the spinal canal, as well as minimizing the risk of developing postoperative spinal instability. The main advantage of laminoplasty over laminectomy with fusion is that motion Common clinical manifestations of cervical myelopathy is preserved with a laminoplasty. The latter is ideal for the include loss of dexterity in the upper extremities (such as myelopathic patient with multilevel stenosis, neutral or unexplained changes in hand writing), gait abnormalities, lordotic alignment and minimal neck pain. If the spine is extremity weakness and, in extreme cases, bowel and kyphotic, laminectomy or laminoplasty is contraindibladder incontinence. Neurological examination typically cated, since the compressing force is anterior, and reveals long tract findings such as hyper-reflexia, spasticity posterior decompression will therefore not address the and clonus. Other pathological reflexes such as a Hoffman source of compression. Under these circumstances, sign and an extensor-plantar response (Babinski sign) also anterior decompression and fusion is preferred. may be present. In addition, objective weakness usually is present, which typically is greater in the upper than the lower extremities. The natural history of CSM usually is characterized by eventual neurologic deterioration, although it may have periods of relative stability. Therefore, the treatment of this condition generally is surgical decompression and fusion. Depending upon the location of the compression and the alignment of the cervical spine, surgery may be performed either anteriorly or posteriorly. If the myelopathy is due to a focal disc herniation, the treatment involves an ACDF. If the pathology is more diffuse and is multisegmental, treatment can involve either anterior or posterior decompression, depending on the location of the compression (anterior or posterior) and the alignment of the cervical spine. If there is lordotic or neutral alignment, surgery generally may be performed either anteriorly or posteriorly. Anterior surgery involves either multilevel discectomy with fusion or corpectomy — in which a large segment of one or more vertebral bodies and intervening/ adjacent discs are removed — with fusion. With either procedure, anterior cervical instrumentation usually is performed. Such extensive anterior surgery is associated with a relatively high risk of dysphagia (usually temporary), and for that reason posterior surgery often is preferred. Gordon R. Bell, M.D. Dr. Bell can be reached at 216.444.8126 or bellg@ccf.org. Relief of arm pain following an anterior fusion is reliable and predictable. Good or excellent results are reported in approximately 85 to 90 percent of patients. The outcome following spinal cord decompression for cervical myelopathy is unpredictable. Therefore, the patient should be told that the goal of surgery is to stabilize his/her neurological function and to prevent further deterioration. In general, milder degrees of myelopathy have a better chance of improvement than more severe myelopathy. Gordon R. Bell, M.D., holds a primary appointment as a Cleveland Clinic spine surgeon, with a joint appointment in the Department of Orthopaedic Surgery, where he serves as vice chairman. His interests include degenerative conditions of the lumbar and cervical spine, spine fractures and athletic spine injuries. Posterior surgery generally involves decompression and some form of stabilization, since laminectomy alone is associated with a risk of developing post-operative clevelandclinic.org/spine The Merits of Cervical Disc Arthroplasty By Thomas E. Mroz, M.D. Cervical spondylosis is a natural and evolving process that occurs with aging. Approximately 60 percent of asymptomatic persons over 40 years of age have radiographic evidence of spondylosis. By age 60, 95 percent of men and 70 percent of women show similar radiographic findings. Thomas E. Mroz, M.D. Dr. Mroz can be reached at 216.445.9232 or mrozt@ccf.org. Nearly 50 years ago, cervical spine fusion was introduced as a treatment for symptomatic cervical spondylosis. Today, anterior cervical discectomy and fusion (ACDF) is a common surgical treatment for symptomatic cervical spondylosis. Yet, it is widely recognized that levels adjacent to a fused cervical segment or segments are prone to develop accelerated degenerative changes, and it is thought that the incidence is 3 percent per year. This may be due to the significant forces transmitted to the adjacent levels following segmental fusion. Adjacent segment degeneration (ASD) is associated with clinical deterioration in some patients, giving rise to what has been termed adjacent segment disease. Disc replacement, also known as cervical total disc arthroplasty (TDA), is a novel technology designed to replace cervical fusion. Theoretically, by maintaining cervical motion, the adjacent level degeneration associated with fusion may be avoided. Similar to lumbar disc replacements, there are various cervical discs with unique mechanical characteristics currently being studied in this country (Figures 1–3). All are designed to preserve motion at the surgical level. The criteria being used for disc replacement in the FDA Investigational Device Exemption clinical trials include: 1) radiculopathy caused by disc hernia ions or bony foraminal stenosis, 2) myelopathy due to soft disc herniation and/or disc/osteophyte complexes, or 3) any combination of 1 or 2. TDA currently is not considered a reasonable treatment for axial neck pain. Cervical arthroplasty is an exciting new technology that may improve clinical outcomes in patients with spondylosis and the variety of associated neurological syndromes. The purported benefits of arthroplasty have not been clinically proven, due to the lack of adequate long-term follow-up from well-designed clinical trials. Considering the current published literature, one can conclude only that single-level arthroplasty is equivalent to single-level ACDF at two years postoperatively. One study suggests that arthroplasty prevents or lessens the degree of ASD at two years postoperatively. This conclusion, however, will need to be validated with longer-term studies. Spinal Column | SPRING 2007 In order for cervical arthroplasty to become a standard of care for cervical spondylosis that is refractory to nonsurgical management, several criteria must be met. First, it must have a clinical benefit that is equal to, or better than, the current standard, ACDF. Second, it must be shown that it is efficacious at preventing or delaying the progression of ASD. The latter is a critical factor regarding the support of the argument in favor of this technology. Third, it must be safe. Finally, arthroplasty must be shown to be cost effective. TDA is becoming an increasingly larger component of the $3 billion implant industry. Arthroplasty is a new, incompletely studied technology, about which many are enthusiastic. Like any new spinal technology, however, it must withstand the scrutiny of well-designed, unbiased studies that prove its efficacy, as has laparoscopic cholecystectomy. However, unique to arthroplasty is the need for long-term outcome studies. This is due to the type of devices employed, the lack of models that simulate the clinical situation, and the nature of the clinical problem (adjacent segment degeneration) it is designed to remedy. Adjacent segment degeneration occurs over a period of years and, as such, a device designed to prevent such a problem needs long-term data to support or refute its efficacy. This is an exciting era of spinal surgery in general, and further research will foster the development of technically advanced and clinically efficacious methods to treat cervical spinal disorders using motion-preserving technology. Thomas E. Mroz, M.D., is a spinal surgeon with Cleveland Clinic. He is interested in cervical spine surgery and minimally invasive spinal surgery, especially complex cervical spine surgery, including cervical deformity, revision surgery, cervical infections, cervical tumors, and cervical myelopathy and radiculopathy. Cleveland CLinic Figure 1: Cervical discs currently being studied in the United States include the: (a) Bryan cervical disk (Medtronic Sofamor Danek, Memphis, Tenn.); (b) Prestige cervical disc (Medtronic Sofamor Danek, Memphis, Tenn.); (c) Porous Coated Motion (PCM) Artificial Cervical Disc* (Cervitech, Rockaway, N.J.); and (d) Prodisc-C (Synthes Spine, West Chester, Pa.). Figure 1a Figure 1b Figure 1c Figure 1d *Caution: Investigational Device, Limited by United States Law to Investigational Use. Figure 2: Illustrations from Cervitech compare their PCM Artificial Cervical Disc (a) to traditional fusion (b). Figure 3: Lateral close-ups of the PCM Artificial Cervical Disc (a) and plate fusion (b). Figures 1a and 1b reprinted with permission from Medtronic Sofamor Danek. Figures 1c, 2 and 3 reprinted with permission from Cervitech. Figure 1d reprinted with permission from Synthes Spine, LLP. Figure 2a Figure 2b Figure 3a Figure 3b clevelandclinic.org/spine Cervical Deformities By R. Douglas Orr, M.D., FRCSC R. Douglas Orr, M.D., FRCSC Dr. Orr can be reached at 216.363.2410 or orrd@ccf.org. The cervical spine is susceptible to a number of forces that it must balance in order to maintain alignment and stability and in order to protect the spinal cord. If these forces are not balanced correctly, deformities can occur. The human head weighs about 10 pounds and is balanced on top of the vertebra of the neck, which are usually less than 2 inches wide and 1.5 inches front-to-back. This configuration has been compared to balancing a bowling ball on a bowling pin. In addition to the vertebra and discs, there are other supporting structures for the head, such as the paraspinal muscles and three strong ligaments: the anterior and posterior longitudinal ligaments and the interspinous ligaments. In addition to providing support, these structures must also allow mobility so that the head can be moved. Failure of any of these structures can lead to deformity. Cervical deformity is an uncommon but complex problem. In many cases, non-operative management is effective and appropriate. Surgery often is indicated and effective, but the surgeries are complex. Patients with symptomatic cervical deformities, therefore, should be assessed by someone experienced in their treatment. Figure 1 Types of Cervical Deformities In the normal spine, a gentle curve is seen when viewed from the side. This curve is called lordosis (Figure 1). The most common pattern of deformity in the cervical spine is the reversal of this curve, called kyphosis (Figure 2). When viewed from the front or back, the cervical spine should be straight. Scoliosis is a curve in the spine when viewed from the front or back and is uncommon in the cervical spine. This condition, when seen, is called torticollis. There are numerous causes of cervical deformities and they can manifest themselves in many ways. Many cause no symptoms and are picked up incidentally, while others do lead to symptoms and require treatment. The predominant symptoms encountered are axial neck pain, arm (radicular) pain and myelopathy (impairment of spinal cord function). Axial neck pain often involves a positional or fatigue pattern and occurs because of the increased energy expended by the paraspinal muscles to hold the head up and maintain a forward gaze when gravity is working to pull the head forward and down. As the deformity increases, so do the energy demands. Radicular pain is caused by nerve root compression and can occur in the distribution of any cervical nerve root. Myelopathy is caused by compression of the spinal cord and can present with gait disturbances or loss of hand function. Treatment Figure 2 10 Spinal Column | SPRING 2007 Treatment of cervical deformities is dependant on the presenting symptom. If the patient is asymptomatic, then observation alone is warranted. Axial neck pain often will respond to a physical therapy program with an active strengthening component. Traction seems like an appealing method of treatment, but has not been shown to be effective. Bracing has been advocated, but only in very rare circumstances is it effective. Typically, not only Cleveland CLinic Figure 1: Lateral view of the cervical spine showing a normal lordotic alignment. Figure 2: Lateral view of the spine showing a kyphotic alignment. Figure 3: Sagittal T2 MRI showing multilevel compression of the cervical spinal cord, both from the posterior and anterior. Figure 4: A post-operative lateral film of the patient in Figure 3 after combined anterior and posterior treatment of the myelopathy and deformity. Figure 3 Figure 4 is it ineffective, but it may in fact worsen the condition. When braces are effective, they unload the cervical muscles. The unused muscles are already weak and brace wear only exacerbates their weakness, which contributes to axial pain. Soft cervical collars have no role in the treatment of any cervical deformity, because they provide no stability, do not restore alignment and wearers tend to lose range of motion. Radicular pain can be treated in a number of ways. Nonsteroidal anti-inflammatory drugs and narcotics each have a role, though narcotic use should be short term. Medications for neurogenic pain such as gabapentin (Neurontin) and pregabalin (Lyrica) have been shown to be effective in some patients. Cervical nerve root blocks and epidural injections also are effective in some patients. If a patient has persistent pain for more than three months, in spite of conservative management, then surgery may be a good option. The presence of a significant deformity complicates the surgical approach. In general, decompressive procedures alone are not a good option, as they tend to exacerbate the deformity. Similarly, treatment of a single-level radiculopathy with single-level surgery is only rarely indicated. As a result, the surgery for cervical deformity often is quite extensive and may involve combined anterior and posterior approaches. The predominant symptoms encountered [with cervical deformities] are axial neck pain, arm (radicular) pain and myelopathy (impairment of spinal cord function). surgery are decompression of the spinal cord and correction of the deformity. This usually will involve a multi-level instrumented fusion and may again need combined anterior and posterior approaches (Figure 4). R. Douglas Orr, M.D., FRCSC, is a spinal surgeon with Cleveland Clinic and also has a joint appointment in orthopaedic surgery. His clinical interests include spinal deformities, spinal tumors, spinal biomechanics and biomaterials, and minimally invasive spine surgery. Myelopathy is a common presenting symptom of cervical deformity and has a different natural history. In general, most cervical conditions are not progressive. Myelopathy, however, almost invariably is progressive, though the rate of progression may be quite slow. Compression on the cord comes from both the degenerative changes seen in deformities and from the draping of the spinal cord over the anterior osteophytes and discs (Figure 3). Typically, the only effective treatment for a cervical deformity with myelopathy is surgery. The goals of clevelandclinic.org/spine 11 Cervical Spine Tumors By Thomas E. Mroz, M.D. The incidence of metastatic disease of the spine far exceeds that of primary neoplasia, and is estimated to account for greater than 95 percent of all spinal tumors. Primary tumors and metastatic disease of the cervical spine are relatively rare, compared to the thoracic, lumbar and sacral regions. Figure 1 The likelihood of malignancy is directly proportional to the age of the patient. In one study of 23 patients with primary cervical spine tumors, all patients younger than 21 years old had benign tumors, while 71 percent of patients older than 21 years had a malignancy. Carcinomas begin to peak in the fourth, fifth and sixth decades, and myeloma and lymphoma begin to peak in the fifth and sixth decades. Certainly, when a patient presents in the fourth decade with an undiagnosed cervical spine lesion, the suspicion of malignancy must be quite high. A difference in tumor location also provides a clue about the tumor type, with benign tumors having a predilection for the posterior elements, and malignancies more often occurring in the vertebral body. Figure 2 Primary Tumors There are many primary benign tumors that affect the cervical spine. Osteochondroma is the most common. Others include osteoblastoma, osteoid osteoma, aneurysmal bone cyst, hemangioma, giant cell tumor and eosinophilic granuloma. Chordomas are the most frequently accounted malignant tumor in the spinal column. However, the cervical spine is not a common site of occurrence; most occur in the sacrum or the clivus. Figure 3 Case Example One A 52-year-old female with mechanical neck pain and no history of primary malignancy was found to have a large tumor involving C3. Pre-operative work-up demonstrated systemic metastasis with a suspected pancreatic primary. Figure 1 shows a lateral x-ray of the cervical spine showing the C3 metastatic lesion. Note the overall lucency and the lytic region of the C3 vertebral body. Figure 2 shows an MRI with contrast of the cervical spine; note the complete replacement of the C3 vertebral body by the tumor. A C3 body resection (corpectomy) with allograft and plate reconstruction, followed by a posterior instrumented fusion was necessary for adequate resection and stabilization. Figure 3 shows a lateral post-operative x-ray. Postoperative chemotherapy and radiation therapy were then administered. 12 Myeloma and solitary plasmacytoma are the most common primary malignancies of the adult spine. They account for approximately 30 percent of all primary spinal malignancies. According to the Mayo Clinic Registry, the cervical spine is involved in 3 percent of all myeloma cases. Non-plasma cell lymphomas account for 10 percent of spinal malignancies, but only 0.8 percent of all lymphomas occur in the cervical spine. Chondrosarcoma also accounts for 10 percent of primary spinal malignancies, but only 1.5 percent of chondrosarcomas affect the cervical spine. Osteosarcomas and Ewing’s sarcomas are highly malignant bone lesions, and together account for 10 percent of the primary spinal malignancies. However, it is estimated that only 0.5 percent and 0.4 percent, respectively, of all osteosarcomas and Ewing’s sarcomas occur in the cervical spine. Metastatic Tumors Skeletal metastasis is a common occurrence, and the spine represents the most commonly affected osseous site. The thoracic spine is the most commonly involved region, followed by the lumbar and cervical regions. The top three most common tumors to metastasize to the spine are breast, lung and prostate. Renal, gastrointestinal, thyroid and bladder tumors also occur in the spine, but at lower rates. Patient Presentation and Treatment Principles Patients with cervical tumors require a thorough evaluation of their histories, physical examinations, and laboratory and imaging studies in order to be properly diagnosed and to formulate the most appropriate and efficacious treatment plans. Patients with cervical tumors can present in many ways, but mechanical neck pain is a common presentation. A pathologic fracture may be heralded by an acute onset of neck pain with or without a neurologic deficit, depending on the fracture type Spinal Column | SPRING 2007 Cleveland CLinic and tumor burden. In patients with an isolated cervical lesion without a known primary, an open biopsy often is necessary to obtain a diagnosis. The treatment of cervical tumors depends primarily on the tumor type, its radio- and chemo-sensitivity, the extent of tumor metastasis (if metastatic) and, importantly, the degree of spinal stability and neural compression. Regardless of whether a non-surgical or surgical regimen is chosen, it is important to have a comprehensive, well-organized team that includes an internist, oncologist, surgeon, dietitian and social worker in order to make the treatment of these patients most efficacious. Surgical resection and reconstruction is required in patients who have neurologic compromise, marked bony destruction, a significant deformity due to fracture or a risk of developing a fracture. The cervical spine has unique biomechanical characteristics and surrounding anatomy. Therefore, it commands more thought and diligence during the decisionmaking process. Surgery for spine tumors requires meticulous technique with appropriate decompression of the neural elements, restoration of normal or nearnormal cervical alignment, the provision of spinal stability, and minimal morbidity and injury to adjacent visceral and vascular structures. Thomas E. Mroz, M.D., is a spinal surgeon with Cleveland Clinic. He is interested in cervical spine surgery and minimally invasive spinal surgery, especially complex cervical spine surgery, including cervical deformity, revision surgery, cervical infections, cervical tumors, and cervical myelopathy and radiculopathy. Thomas E. Mroz, M.D. Dr. Mroz can be reached at 216.445.9232 or mrozt@ccf.org. Case Example Two An 84-year-old male with neck pain and a history of B-cell lymphoma had a large, destructive lesion of C2 (Figures 4–6). He underwent an occipitocervical fusion for stabilization followed by radiation therapy (Figure 7). He is now three years post-op, and doing well. Figure 4 Figure 5 Figure 6 Figure 7 clevelandclinic.org/spine 13 A Look at the Cervical Spine continued from page 1 Locations surgery can accelerate the progression of deformity, and extreme surgical measures may be required to correct the deformity. Dr. Orr reviews the types of cervical deformities and various treatment options on page 10. A variety of tumors and tumor types can involve the cervical spine. Although not a common cause of symptoms, tumor involvement of the cervical spine can lead to major morbidity and mortality. Henceforth, their impact may be great. Dr. Mroz reviews the instances and effects of cervical spine tumors on page 12. I hope you enjoy this collection of well-illustrated articles and that they provide insight into this interesting and perhaps most misunderstood aspect of spine care. Edward C. Benzel, M.D., is a Cleveland Clinic spinal surgeon. Cleveland Clinic 9500 Euclid Avenue Cleveland, OH 44195 216.444.BACK (2225) Solon Family Health Center 29800 Bainbridge Road Solon, OH 44139 440.519.6800 Beachwood Family Health and Surgery Center 26900 Cedar Road Beachwood, OH 44112 216.839.3000 Strongsville Family Health and Surgery Center 16761 SouthPark Center Strongsville, OH 44136 440.878.2500 Euclid Hospital 18901 Lake Shore Blvd. Euclid, OH 44119 216.692.8222 Westlake Family Health Center 30033 Clemens Road Westlake, OH 44145 440.899.5555 Lutheran Hospital 1730 West 25th Street Cleveland, OH 44113 216.363.2410 Outcomes Data Available The latest outcomes data in spine care are available. Our outcomes booklet also offers summary reviews of medical and surgical trends and approaches. Charts, graphs and data illustrate the scope and volume of procedures performed in our department each year. To view outcomes booklets for spine, as well as many other Cleveland Clinic medical and surgical disciplines, 14visit clevelandclinic.org/quality. Spinal Column | Winter 2007 Cleveland CLinic Willoughby Hills Family Health Center 2570 SOM Center Road Willoughby Hills, OH 44094 440.943.2500 Cleveland Clinic Spine Clinical Trials Prospective outcomes evaluation of decompression with or without instrumented fusion for lumbar stenosis with degenerative grade I spondylolisthesis Edward Benzel, M.D. 216.445.5514 Comparing surgical to conservative management in the treatment of Type II odontoid fractures among the elderly Edward Benzel, M.D. 216.445.5514 Anterior cervical fusion augmented with autologous marrow: a controlled, prospective, randomized trial Robert McLain, M.D. 216.444.2744 Pilot study assessing the use of Cortoss, a synthetic cortical bone void filler in kyphoplasty Isador Lieberman, M.D. 216.445.2743 Application of seating support for patients with coccygodynia Prospective, randomized clinical investigation of the Cervitech, Inc., Porous Coated Motion Artificial Disc for stabilization of the cervical spine in patients with DDD and neurological symptoms at one level (C3– C4 or C7–T1) Richard Schlenk, M.D. 216.445.4318 Gaurav Kapur, M.D. 216.445.7378 Comparison of femoral ring allograft with supplemental translaminar facet screw fixation versus stand-alone anterior lumbar interbody fusion cages Douglas Orr, M.D. 216.363.2410 Isador Lieberman, M.D. 216.445.2743 The prediction of pain reduction in the treatment of facet joint syndrome monitored by CERSR technology An assessment of surgical techniques for treating cervical spondylotic myelopathy Thomas Mroz, M.D. 216.445.9232 Daniel Mazanec, M.D. 216.444.6191 Upcoming Symposia February 23–25, 2007 First International Symposium on Stereotactic Body Radiation Therapy and Stereotactic Radiosurgery Grand Floridian Resort and Spa Lake Buena Vista, Florida July 18–24, 2007 Cleveland Spine Review InterContinental Hotel & Conference Center Cleveland, Ohio August 3–9, 2007 Egyptian Spine Review and Hands-on Course Cairo, Egypt August 24–25, 2007 Innovative Spine Care: Essential Skills for the Nursing Team InterContinental Hotel & Conference Center Cleveland, Ohio Contact Martha Tobin at 216.445.3449 or 800.223.2273, ext. 53449, or at tobinm@ccf.org for seminar details. clevelandclinic.org/spine 15 Spinal Column The Cleveland Clinic Foundation 9500 Euclid Avenue / W14 Cleveland, OH 44195 For referrals to Cleveland Clinic spine physicians, call 216.444.2225 Spinal Column | SPRING 2007 the cervical spine Cleveland Clinic is ranked third in the nation in U.S.News & World Report’s 2006 Best Hospitals Survey. Co-Editor: Edward C. Benzel, M.D. Co-Editor: Daniel J. Mazanec, M.D., F.A.C.P. Dr.Connect: Physician Leader: Thomas E. Mroz, M.D. Online Access to Your Patient’s Medical Record Marketing Program Manager: Ellie Palmer Whether you are referring from near or far, our new e-Cleveland Clinic service, Dr.Connect, can streamline your communication with our specialists. This new online tool offers you secure access to your patient’s Cleveland Clinic medical record. You can track your patient’s care in real time, without additional software or hardware other than an Internet connection. To establish a Dr.Connect account, please call 877.224.7367 or e-mail drconnect@ccf.org. Managing Editor: Christine Coolick Spinal Column is published by Cleveland Clinic to provide up-to-date information about our spine physicians’ research and services. The information contained in this publication is for research purposes only and should not be relied upon as medical advice. It has not been designed to replace a physician’s independent medical judgment about the appropriateness or risks of a procedure for a given patient. MKT 06-SPC-008