Causes. Causes Of Degenerative Disc Disease: The intervertebral discs, otherwise referred to as spinal discs, intervertebral fibrocartilage, are elastic bodies composed of a fibrocartilage tissue material, which supply cushioning in between the bones of the spine i.e. Prolapse of intervertebral disc or spinal disc herniation or herniated disc is a condition where the central gelatinous part of the intervertebral disc moves out of its position. As the intervertebral disc ages, Review the available Assessment Questionnaires for the symptoms of Intervertebral disc disease:Back pain -- Assessment QuestionnaireNeck pain -- Assessment QuestionnaireLeg pain -- Assessment QuestionnaireLeg weakness -- Assessment QuestionnaireLeg numbness -- Assessment QuestionnaireLeg tingling -- Assessment Questionnaire Intervertebral disc (IVD) health is an important factor in overall spine health and the incidence of low back pain. Researchers have identified variations in several genes that may influence the … Intervertebral disc disease refers to a herniated disc in the spine. These discs act as shock absorbers and minimize the impact of movement on the vertebrae. intervertebral disc disease, any part of the spine can have disc degeneration. Researchers have identified variations in several genes that may influence the … Lumbar (intervertebral) disk disease is a frequent source of low back pain. Factors such as occupational stress, trauma, or obesity, together with genetic alterations, may result in the structural weakness of a disc, cause a herniation, and possibly initiate a cascade of events leading to sciatica and pathological disc changes. Lumbar Intervertebral Disk Disorders Causes/PLID is one of the most common vertebral column diseases of elderly people leading to back pain, radicular pain, and subsequently neurological deficit due to nerve root compression. Disc herniation refers to displacement of disc material beyond the intervertebral disc space. This rupture leads to damage to the spinal cord. Intervertebral disc disease (IVDD) is an age-related, degenerative condition. This is the American ICD-10-CM version of M51.16 - other international versions of ICD-10 M51.16 may differ. Intervertebral disk degeneration that causes clumping of the nuclear material and relative mechanical instability is the necessary preceding condition for HNP. the vertebrae. Disk herniation is most often the result of a gradual, aging-related wear and tear called disk degeneration. Compression is usually the result of gradual degeneration, causing the central gel of the disc to lose its fluid and become more susceptible to general wear and tear. Prolapsed Intervertebral Disc or Slipped Disc is a condition when the outer fibres of the intervertebral disc are injured and the nucleus pulposus ruptures out of its enclosed space. For a physician, a disc disorder is any problem with the disc(s) between the vertebrae. The main types of disc disorders are: Herniated or ruptured disc. Degenerative disc disease. Thinning disc. Bulging disc. It may not be related to injury, although the rupture frequently occurs after some sort of traumatic event, such as a fall or a relatively small jump. The most common cause of paralysis in dogs is intervertebral disk disease.Most dogs that suffer from disk disease can be cured with medical or surgical treatment, and so their paralysis is only temporary. Cauda equina syndrome, a syndrome where the nerves at the bottom of the spinal cord are compressed by an intervertebral disc or a mass, is a rare complication of spondylosis that can cause severe nerve problems. Diagnosis of Prolapsed Intervertebral Disc Disease (PIVD) Diagnosis of prolapsed intervertebral disc disease is done for both Cervical and Lumbar Spine, by checking the history and physical examination. Intervertebral Disc Syndrome (also known as IVDS) is a back condition involving the intervertebral disc or disc fragments. Cervical Spine. Degenerative disk disease is when normal changes that take place in the disks of your spine cause pain. Thoracic disc lesions are primarily degenerative of nature and affect mostly the lower part of the thoracic spine. the vertebrae. Degenerative disc disease is an age-related condition that happens when one or more of the discs between the vertebrae of the spinal column deteriorates or … This is a simple fact of human anatomy. This is also known as a “slipped” disc. These discs can press on nerves, causing pain , nerve damage , and paralysis . Short description: Intervertebral disc disorders w radiculopathy, lumbar region The 2022 edition of ICD-10-CM M51.16 became effective on October 1, 2021. A Clumber Spaniel has relatively short legs and a long back. Prevention. In type I IVDD, the intervertebral disc degenerates and suddenly herniates upward into the spinal cord, resulting in pain and often in weakness or even paralysis. IVDD (Intervertebral Disc Disease) is a degenerative disease that can affect your dog's spinal cord and causes a range of painful symptoms. One such disease that is responsible for back pain is Degenerative Disc Disease (or DDD for short). There are some spinal conditions that result in paralysis, which is the inability to move the legs. What causes Intervertebral Disc Disease in dogs? IVDD cases range from mild or moderate (Type I) to severe (Type II). Watch: Lumbar Degenerative Disc Disease Video. Degenerative disc disease causes herniated discs. Intervertebral disk disease (IVDD) in dogs can be described as a slipped disk, ruptured disk, herniated disk, or bulging disk. Clinically, the symptoms associated with intervertebral disc syndrome can respond to the application of spinal manipulation. Occasionally, the annulus may tear and fragment, with the fragmented piece compressing the spinal cord. Intervertebral Disc Disease (IVDD) is by far the most common health problem in UK Dachshunds: around 1 in 4 may be affected at some stage in their lives. Degenerative disk disease is most common in older adults. Bulging, protruding, extruding, or sequestered disks can result in lumbar disc disease. Intervertebral disc disease can be caused by one of two types of damage to the spinal cord: compression and concussion. This condition typically progresses more slowly and is caused by a chronic bulging of the disc’s outer portion (the annulus) on the spinal cord, which can atrophy as a result of chronic compression. IVDS can also cause nerve pain in the legs and arms, depending on where the displaced disc … Obesity. Common causes of dog back pain include: old age, spinal injury, and diseases such as Intervertebral Disk Disease (IVDD).. 1. In this lesson you will learn about the spine, the intervertebral discs, and how changes to the intervertebral disc result in severe degenerative disk disease, which is not really a … One of the most common musculoskeletal disorders, it has strong genetic determinants (Matsui et al., 1998; Battie et al., 1995; Sambrook et al., 1999). Intervertebral disc degeneration occurs in 58% of asymptomatic patients, suggesting that disc degeneration alone is not painful (Borenstein et al., 2001; Hurri & Karppinen, 2004). Intervertebral disc disease (IVDD) is an age-related, degenerative condition. Also called a slipped disc, this type of disc disease can happen anywhere along the spine. Intervertebral disc syndrome is a common cause of back pain. The mechanism of sciatic nerve injury is either a result of direct nerve compression, inflammation, an abnormal immune system response of the body, … There are three types of IVDD you should know about: Type 1. The book covers the full range of problems frequently encountered in the clinical setting, including traumatic injuries, … Degenerative disc disease in the lumbar spine, or lower back, refers to a syndrome in which age-related wear and tear on a spinal disc causes low back pain. Intervertebral Disc Syndrome can also cause nerve pain in the legs and arms, depending on where in the spine the displaced disc is located. However certain, ‘at-risk’ dogs ( chondrodystrophic breeds and crosses) can suffer disc problems from when they are young adult dogs. 1, 2 Behavior of the spinal motion segment consistent with subluxation (altered alignment, movement integrity, and physiological function) is observed with disc degeneration and herniation. Causes of Intervertebral Disc Disease in Dogs Intervertebral disc disease can be caused by one of two types of damage to the spinal cord: compression and concussion. Intervertebral disc disease (IVDD) is the most common spinal cord disease of dogs, being responsible for 2.3–3.7% of admissions to veterinary hospitals (1, 2).The diagnosis of all IVDD forms is based on imaging, with the imaging techniques evolving over the years. In many cases this condition will go undetected until the disc becomes ruptured. Intervertebral disc disease (IVDD) is the most common spinal condition in canine patients. For example, IVDS may result in chronic back pain and limitation of motion (a chronic orthopedic manifestation); back pain and limitation of motion may also cause periods of acute incapacitation. The new edition of this book provides the current information on the diagnostic techniques and therapeutic approaches that will help clinicians optimize care for patients with intervertebral disk disease. Intervertebral disc disease (IVDD) is a very serious and common disease seen in thousands of dogs every year. IVDD can cause pain over … In fact, patients with degenerative disc disease have marked enrichment of nociceptive nerve fibers in the endplate region as opposed to the disc (Brown et al., 1997). Causes of Degenerative Disc Disease in the Neck Simple wear and tear is the usual culprit responsible for cervical degenerative disc disease . Intervertebral disc disease results from a combination of genetic and environmental factors. The unique architecture of the discs prevents the vertebrae from crushing against … Compression is usually the result of gradual degeneration, causing the central gel of the disc to lose its fluid and become more susceptible to general wear and tear. Studies on the relationship between osteoporosis and intervertebral disc degeneration (IVDD) are inconsistent. Intervertebral disc degeneration primarily causes thoracic discogenic pain syndrome. Unlike other musculoskeletal systems, degenerative changes in the spine appear from the late teens or early twenties. Intervertebral Disc Disease (IVDD) is a degenerative disease that can affect your dog's spinal cord and causes a range of painful mobility issues. Intervertebral disc disease (IVDD) is one of the major causes of back pain; no therapeutics are currently available to reverse this disease. The impact of bone mineral density (BMD) on IVDD has been controversial, with some studies suggesting osteoporosis as causative for IVDD and others suggesting it as protective for IVDD. This can cause wobbling and incoordination, pain, nerve damage, and even lower body paralysis. Intervertebral discs normally degenerate as dogs get older. This can cause wobbling and incoordination, pain, nerve damage, and even lower body paralysis. The cause of IVDD in dogs is degeneration and breakdown of the tissue that forms the cushioning disc between vertebrae. Our Matthews NC veterinary neurologists specialize in the diagnosis and treatment of disorders of the brain, spinal cord, muscles and nerves of pets. Intervertebral Disc Disease. Any breed can get intervertebral disc disease, even cats can develop it. As the disc deteriorates, it affects the structure of the … IVDS can cause chronic pain in the back, usually made worse by prolonged sitting or bending. Disc degeneration is thought to occur because of loss of the disc to “hold water” becoming dehydrated. What is intervertebral disc degeneration, and what causes it? The most common causes of IVDD are conformation and age, Over time, the discs in your dogs back lose their flexibility, making them more susceptible to injury. Degenerative disc disease develops as the spine’s intervertebral discs face degenerative changes, and this can lead to the development of an unnatural spinal curvature: degenerative scoliosis. Intervertebral Disc Disease (IVDD) is a degenerative disease that can affect your dog's spinal cord and causes a range of painful mobility issues. Exact symptoms vary depending on the location and type of disc degeneration. Intervertebral disc rupture is a sudden and very painful occurrence that propels parts of the disc material into the area surrounding the spinal cord and causes spinal cord inflammation and injury. 2016 2017 2018 2019 2020 2021 2022 Billable/Specific Code. To help prevent a herniated disk, do the following: Exercise. Depending on the location of the affected disc or discs, intervertebral disc disease can cause periodic or chronic pain in the back or neck. Back pain, regardless of the location or The disc material “squeezes” out of the normal position and puts pressure on nerves to cause pain. Saddle anesthesia. Watch: Lumbar Degenerative Disc Disease Video Intervertebral discs are tough, fibrous structures that act as ligaments between vertebrae, absorbing pressure and providing cushioning for the spinal column. Intervertebral disc disease is a common problem in dachshund type dogs that causes damage to the spinal cord that can be permanent. Underlying causes include genetic inheritance, age, inadequate metabolite transport, and loading history, all of which can weaken discs to such an extent that structural failure occurs during the activities of daily living. Causes. How Do You Know If An Animal Is A Carrier Or Likely to Become Affected? Some of these factors have been identified, but many remain unknown. Intervertebral disc disease results from a combination of genetic and environmental factors. It is a common cause of back pain. Discitis, or diskitis, is an infection in the intervertebral disc space that affects different age groups. Smoking. However, IV disc herniation can occur in any breed—even in cats. Biological sex, with women being more likely to experience symptoms. Causes of Intervertebral Disc Disease in Dogs Intervertebral disc disease can be caused by one of two types of damage to the spinal cord: compression and concussion. Dogs with Type I disease generally heal over time and are able to resume their normal routine and walking. However, intervertebral herniations which are caused by DDD are rarely symptom-generating. Three quarters of incidence occurs below T8, with T11-T12 being most common. Intervertebral discs are cushioning pads of fibrocartilage that sit between most of the vertebra of the spinal column. Dyspnea, tachycardia, nervousness, fatigability, etc., may result from many causes; some may be service connected, others, not. Intervertebral disc disease is one of the most common musculoskeletal disorders. There are many reasons a dog may be suffering from back pain. Although intervertebral disc disease (IVDD) is seen less frequently in cats than dogs, it is still a serious condition. Sometime called a "slipped disc," any dog can develop IVDD. Compression is usually the result of gradual degeneration, causing the central gel of the disc to lose its fluid and become more susceptible to general wear and tear. Degeneration of the intervertebral disc begins early in life and is a consequence of a variety of environmental factors. They often refuse to flex or extend their neck to eat and sudden movements can cause them to cry out. Most people can't pinpoint the cause of their herniated disk. Many people suffer from neck pain and low back pain at some point during their life. Pressing on the nerves in the spinal cord, these disks can cause pain, nerve damage, loss of bladder and bowel control, and paralysis. Some individuals present predominantly or exclusively with acute symptoms, some with chronic symptoms, and some with both. The intervertebral disc is a cartilaginous structure that resembles articular cartilage in its biochemistry, but morphologically it is clearly different. Type I disc disease is characterized by disc herniation ("slipped disc") and a sudden onset of signs. Call +91-124-4141414 to know more about its symptoms, treatment and surgery. The patient's who experience pain related to a herniated disc often remember an inciting event that caused their pain. [1] It occurs most often in the thoracolumbar region. It is proposed that intervertebral disc degeneration should be defined as an aberrant, cell-mediated response to progressive structural failure. Although any dog (or person) can rupture an intervertebral disc by getting hit by a car, slipping on the ice and landing on their back, being obese and carrying too much weight on the spine, and many other causes, intervertebral disc disease is an inherited condition. The gel-like center of each disc, called the nucleus pulposus is encased or surrounded by the annulus fibrosus—a tough layer of fibrocartilage that could be likened to a radial tire. The disease is caused when the cushioning discs (which function like shock absorbers) between the vertebrae of the spinal column begin to harden. Degenerative disc disease can cause pain, weakness, or numbness. Dr. Kari Foss, a veterinary neurologist at the University of Illinois Veterinary Teaching Hospital in Urbana, sees dogs every day that suffer from intervertebral disc disease, or IVDD. The term "intervertebral disc derangement" is a term that has been coined by physical therapists and manual therapy practitioners.1,2 I borrow the term "disc derangement" which was originally coined by a physical therapist in New Zealand.3 There is no universally accepted terminology to describe this particular syndrome. It is likely that several factors are needed for development of IDD. There is no gender predisposition, but certain dogs are more predisposed to IVDD, particularly chondrodystrophic breeds … IVDD Back Pain. Intervertebral disc disease (IVDD) is a condition where intervertebral discs between a dog’s spinal vertebrae bulge or burst. As a disc degenerates, small bony outgrowths (bone spurs) may form at the edges of the affected vertebrae. Bulging or bursting intervertebral discs can enter the spinal cord space and put pressure on spinal nerves. The middle portion of the disc (nucleus pulposus) can become ruptured due to tears in the outer part of the disc (annulus fibrosis). The Nobel Prize for Physiology or Medicine has been conferred in 2017 to … An intervertebral disc (or intervertebral fibrocartilage) lies between adjacent vertebrae in the vertebral column.Each disc forms a fibrocartilaginous joint (a symphysis), to allow slight movement of the vertebrae, to act as a ligament to hold the vertebrae together, and to function as a shock absorber for the spine. Types of Intervertebral Disc Disease. 1 Understanding the possible causes of sciatica can help focus treatment on addressing the root problem rather than just masking the symptoms. Intervertebral disc disease (IVDD) is a common cause of pain and other symptoms in dogs. The intervertebral disc can become herniated as a result of being ruptured, bulging, or torn. It can be subdivided using the percentage or angle of disc material herniated 6: For classification purposes the intervertebral disc is considered a round structure consisting of … Introduction Cervical degenerative disc disease is a condition that can compress the spinal cord and nerves in the neck. IVDD occurs when the disc that sits between two vertebrae to cushion or absorb movement in the spine … Degenerative disc disease causes spontaneous degeneration of the outer part of the disc, resulting in sudden disc rupture or herniation (also called a "slipped disc"). IVDD means an animal can, and probably will, rupture one or more discs throughout their lifetime. L5-S1 disc protrusion is a defect of the fibrous ring between the first sacral and fifth lumbar vertebrae. Symptoms such as pain, weakness, and even paralysis can occur as a result of this rupture process, called intervertebral disc extrusion. If the bulging disc presses on a spinal nerve, then that area of the body that the nerve supplies will … In other tissues, nutrients are distributed to the cells through the cardiovascular system, however, IVD tissue is largely avascular in nature. Intervertebral disc rupture is a sudden and very painful occurrence that propels parts of the disc material into the area surrounding the spinal cord and causes spinal cord inflammation and injury. Intervertebral Disc Disease (IVDD) in Cats. Intervertebral disc disease occurs when the discs between your dog's vertebrate start to become weakened with age or trauma. The first cause of sciatica is the result of a Herniated Disc. What is intervertebral disc degeneration, and what causes it? The disease is most common in older … Spinal disks are like shock absorbers between the vertebrae, or … ... and the various symptoms of pain and paralysis attributable to disease affecting the lumbar vertebrae and the intervertebral disc. Let’s talk about degenerative disc disease and how you can treat and manage your back pain using the Backrack technology. [] Risk factors include age, activity, smoking. Intervertebral disc disease results from a combination of genetic and environmental factors. The interrelationship of the spinal three-joint … Symptoms such as pain, weakness, and even paralysis can occur as a result of this rupture process, called intervertebral disc extrusion. Therefore, we assessed whether IVDD is affected by vertebral osteoporosis in ovariectomized mice and investigated the underlying pathogenesis of IVDD related to osteoporosis. However, some breeds are predisposed to intervertebral disc disease because they are born with a defect in the development and maturation of their cartilage, including that in the discs. Introduction. Underlying causes of disc degeneration include genetic inheritance, age, inadequate metabolite transport, and loading history, all of which can weaken discs to such an extent that structural failure occurs during the activities of daily living. When damaged discs in the lumbar spine cause symptoms of pain, it is called lumbar degenerative disc disease. Pain is often worse when sitting, bending, twisting, or lifting objects. By conformation, it is the shape of your dog. Some of these factors have been identified, but many remain unknown. Some factors increase your risk of developing degenerative disk disease, including: Acute injuries, such as falling. These dogs are called chondrodystrophoid and include: Dachshunds. Prolapse of intervertebral disc or spinal disc herniation or herniated disc is a condition where the central gelatinous part of the intervertebral disc moves out of its position. Thirty healthy female C57BL/6 J mice aged 8 weeks were … The Spine Journal, the official journal of the North American Spine Society, is an international and multidisciplinary journal that publishes original, peer-reviewed articles on research and treatment related to the spine and spine care, including basic science and clinical investigations.. In adults, it can lead to severe consequences, such as sepsis or epidural abscess, but it can also spontaneously resolve, especially in children under 8 years of age.Discitis occurs post-surgically in approximately 1–2 percent of patients after spinal surgery. Intervertebral disc disease (IVDD) is a common cause of spinal pain and difficulty walking in dogs. Our Matthews NC veterinary neurologists specialize in the diagnosis and treatment of disorders of … Intervertebral disc disorders with myelopathy, lumbar region. Unlike mechanical back pain, herniated disc pain is often burning or stinging, and may radiate into the … The definitive guide to intervertebral disk diseases. Therefore, spinal stenosis in the neck or low back can be a complication of spondylosis. IVDD is a degenerative (gradual) process, but a jump or fall can damage a disc that has already been weakened by IVDD and bring on an acute phase of the disease. Lumbar intervertebral discs are secured in place by the fibrous endplates of the superior and inferior vertebral bodies. Degenerative disc disease (DDD) is a painful condition arising from damage to the intervertebral discs. Today we look at IVDD in dogs. However, the primary symptoms of degenerative disc disease include sharp and/or chronic pain in the back and neck. Often combined with antesponilolistezom, retrospondilolistezom, spondyloarthrosis, uncoarthrosis, intervertebral hernia. Spinal disks are like shock absorbers between the … As the discs undergo change, the body may react and develop bony growths called bone spurs. As you age, your disks become less flexible and more prone to tearing or rupturing with even a minor strain or twist. IVDD is a gradual degenerative process that affects the spinal cord of the dog over a period of time. Whilst many recover well in time, there is significant risk of permanent damage so severe it is life changing or threatening. Intervertebral disks are the “cushions” in the space between spinal vertebrae. Working a physically demanding job. Intervertebral Disc Disease (IVDD) is a degenerative disease that can affect your dog's spinal cord and causes a range of painful mobility issues. Intervertebral disc disease is a serious condition seen more often in dogs than cats. Our Matthews NC veterinary neurologists specialize in the diagnosis and treatment of disorders of … Cauda equina syndrome can cause incontinence or difficulty urinating even with a full bladder. It … Intervertebral disk disease (IVDD) is the most common cause of spinal cord injury in dogs. ... Nutritional pathways to disc degeneration. A herniated disc in the spine is a condition during which a nucleus pulposus is displaced from intervertebral space. Disc disease is more prevalent in certain breeds of dogs (Dachshunds, Beagles, Shih Tzus/Lhasas, Bichons, Cocker Spaniels, Corgis, and French Bull Dogs). When damaged discs in the lumbar spine cause symptoms of pain, it is called lumbar degenerative disc disease. With IVDS, these discs may be displaced at the lumbar, cervical, or thoracic areas of the spine. Referred pain rather than radicular 4. This pressure can cause symptoms ranging from severe pain to weakness to … These disks are subject to a number of degenerative conditions and forces that predispose them to bulge or rupture over time. If the disc degenerates or is damaged in some way, the disc may bulge and put pressure on the spinal cord and/or the roots of the spinal nerves that come off the sides of the spinal cord. Intervertebral disc degeneration results in diminished shock-absorbing capacity, and can ultimately lead to disc herniation and spinal cord compression. Back pain is a common condition with a high social impact and represents a global health burden. Our Rock Hill veterinary neurologist specializes in the diagnosis and treatment of disorders of the brain, spinal cord, muscles and nerves of pets. Researchers have identified variations in several genes that may influence the … Intervertebral disc disease refers to a herniated disc in the spine. It can be due to a spinal injury or another issue, and while there is no way to prevent it, you can reduce the risk and know how to best care for your injured dog. This is because the nucleus of degenerated discs has shrunk in size and decreased in its ability to pressure neurological tissue upon bulge or rupture. A very common area of the lesion, it can be observed in half the cases of protrusions of the lumbar region. Aging can cause the discs to lose fluid, collapse, and sometimes rupture. Intervertebral disc (IVD) degeneration is a common finding on spine imaging that increases in prevalence with age. 1.Introduction. Intervertebral disc disease (IVDD) is a condition where intervertebral discs between a dog’s spinal vertebrae bulge or burst. upper deck. Found mostly in ageing adults DDD is the cause for loss in intervertebral disc space or the narrowing height of disc. Intervertebral Disc Disease (IVDD) is a condition that over time causes damage and degradation to your dog’s spinal cord. Disc herniation most commonly occurs in dogs between 4 and 7 years of age and dachshunds are affected … Intervertebral disc disorder(IDD) It … Usually preceded by multiple episodes of less severe low back pain Some of these factors have been identified, but many remain unknown. Causes Of Degenerative Disc Disease: The intervertebral discs, otherwise referred to as spinal discs, intervertebral fibrocartilage, are elastic bodies composed of a fibrocartilage tissue material, which supply cushioning in between the bones of the spine i.e. Severe injury is another common cause of intervertebral disc disease. However, it is impossible to tell which patients will do well after microdiskectomy for a herniation and which will have continued problems, of varying severity, from the disk degeneration. The term "intervertebral disc derangement" is a term that has been coined by physical therapists and manual therapy practitioners.1,2 I borrow the term "disc derangement" which was originally coined by a physical therapist in New Zealand.3 There is no universally accepted terminology to describe this particular syndrome. Low back pain (LBP) from degenerative disc disease (DDD) is one of the most common disorders and a major public health problem in the world , , , , . IVDD most frequently affects chondrodystrophic dogs—those characterized by having short legs and long backs, like the Dachshund and Bassett hound for example. Newer imaging techniques in the evaluation of intervertebral disorders are described. Cervical intervertebral disc disease accounts for 36% of all spinal intervertebral disc disease, second only to lumbar disc disease, which accounts for 62% of all spinal intervertebral disc disease. It is a breed characteristic for their intervertebral discs to age faster than the rest of their bodies. Intervertebral Disc Disease This is a condition in which the discs between the vertebrae in the spine bulge or herniate into the spinal cord space .