I'd like to move now on to the neurological classification. The International Standards for Neurologic Classification of Spinal Cord Injury have been developed, refined, and revised by the American Spinal Injury Association and the International Spinal Cord Society. This is the grading sheet that is commonly used. This one is the revised 2019 version. You can find a copy online at the URL https://lms3.learnshare.com.aspx. This is the American Spinal Injury Association website and has free access to this material for documentation. I'd like to go over the components of the neurologic exam and the classification of this, starting with the sensory exam. As you can see on the dermatome chart on the right, the body is divided into dermatomes. We use key sensory points as the definition of the location to test. These points were developed over time to find the most consistent location for sensory and comparing various dermatomal maps, these provide the best approach to identifying sensory level. For example, pinprick and light touch are tested at each of these 28 points, compared to the sensation above the injury as on the face. They're scored on three-point scale, zero being absent, one being impaired, and two being intact. In the case of sharp and dull discrimination, in order for them to have a normal sensation, they have to be able to distinguish between sharp and dull, and it needs to feel as sharp as it does above their level of injury. If they are unable to differentiate between sharp and dull, then for pin sensation, their score would be zero. If they are able to distinguish between sharp and dull, but it is not quite as sharp as it is above their level of injury, then it would be scored a one. Deep anal pressure is the ability to sense the examiner's finger in the rectum. Many people with new injuries will want to feel something, and so oftentimes when doing this exam, it is important to have your finger testing in the rectum, do you feel this? And then outside of the rectum, not touching the patient, do you feel this? Making sure that a positive answer is consistent with reality. The deep anal pressure is then scored yes or no. Each of these sensory key points will help determine the sensory level and the degree of completeness. The motor exam is based on five key muscles in each limb. These were selected because they can be tested in the supine position without rolling the patient or sitting the patient up or having them stand. Each of these are graded on the typical zero to five point manual muscle testing in which zero is total paralysis, a one is a palpable or visible muscle contraction, two is active movement with full range of motion with gravity eliminated. Grade three is the active movement through a full range of motion against gravity, and a grade four is full range of motion with moderate resistance, and a five is against full resistance. Here we test five key muscles in each limb. In the upper extremities, we test the elbow flexors representing the C5 myotome, the wrist extensors representing the C6 myotome, the elbow extensors representing the C7 myotome, and the deep finger flexors representing the C8 myotome. In order to adequately test the deep finger flexors, one has to stabilize the first interphalangeal joint and test only the flexion of the distal phalanx of the middle finger. Finger abduction, specifically of the little finger, is testing the T1 myotome. Each are scaled on a, each are graded on a zero to five scale and summed right and left to give an upper motor, upper limb total score with a maximum of 50. In the lower extremities, or the following muscles, L2 is represented by the hip flexors, L3 by the knee extensors, L4 by the ankle dorsiflexors, L5 by the long toe extensors, specifically of the big toe, and S1, the ankle plantar flexors. Now when testing ankle plantar flexors in a neurologically intact person, the test has them standing one-legged and doing heel rises in order to test this because of the strength of the ankle plantar flexors. This is pretty much impossible to test with your hands, and so it's a judgment, a judgment of whether or not this is normal resistance, full resistance, moderate resistance, or something less than that. And again, the total lower limb score can be calculated. Finally, the motor exam includes voluntary anal contraction. Yes or no? Is this present or absent? It is important to differentiate between anal reflexes because in a person with spinal cord injury and an upper motor neuron pathology, simply inserting your finger into their rectum will trigger an anal sphincter reflex contraction. This is not the same as a voluntary anal contraction, and so one has to be careful as you're examining to not move the finger that is in the rectum while you're asking the person to contract their anal sphincter as if they're trying to stop a bowel movement or release of air. Don't ask them to bear down because for many people that means try to push out a bowel movement and you may be confused because of feeling the rectal mucosa descend into your finger. Make sure that you're focusing on the voluntary anal contraction. Now for motor levels between T1 and L2, we simply match the motor level to the sensory level. This allows us to identify functional motor level even though we don't have a key muscle to test throughout the trunk and abdomen. The definitions of the levels of injury are multiple. We have sensory level is the most caudal, normally innervated dermatome with both modalities. So it has to have a 2 in pinprick and a 2 in light touch with all the dermatomes above that being intact. The motor level is the most caudal key muscle with a grade of at least 3 as long as the key muscle above it is grade 5. So as you're doing your motor exam, you start at the top and you go down and you find your last key muscle that has a 5 out of 5 grade. If the one below that is at least a grade 3, the grade 3 level with the one above it counts as an intact motor level. If that level below the last grade 5 is a 2 or a 1 or a 0, that level does not count. I like to think about this as going for the extra point in football. You can only go for one point. You can't try to go for two. But with one point, if the level below the 5 is a 3, it goes through the uprights. If it's a 2 or lower, it's wide left or wide right. You don't get credit for that one more segment. We use the same definition for the motor level as a sensory level whenever there is not a key sensory or a key motor muscle to test. So above in the cervical level, C1 through 3, through the thoracic and upper lumbar, and in the lower sacral roots as well. The sensory level equals the motor level. We determine a right and a left sensory and motor level separately. So there can be four individual distinct levels. But the neurological level of injury is the most rostral level that has everything intact. The sensory and the motor are intact at that level. And below that, there may still be normal levels. But this gives a single neurologic level of injury for ease of communication. A complete injury is defined as the absence of motor and sensory function in the lowest sacral segment, which is S4-5, which would include no deep anal sensation and no voluntary anal sphincter contraction. An incomplete injury is when one or more of the following is present. Right touch or pinprick or deep anal pressure is present at the S4-5 dermatome, or there is voluntary anal contraction. We use a sacral sparing definition for completeness and incompleteness because this has been demonstrated to be more stable over time. The zone of partial preservation has recently undergone modification and can be documented as the most caudal segment with preservation of any sensory function for a sensory ZPP or motor function for a motor ZPP when those segments are not present in the lowest sacral segment. So for a person who has sensation perianally but no voluntary motor contraction, they may have a motor ZPP at their last motor level with any function involved. It does not have to be normal, any function. And the same with the sensory ZPP. Even if they're incomplete because of anal motor contraction but have no sensory sparing, they could have a sensory zone of partial preservation documented as the last segment that has any sensory activity. Now the age impairment scale is used to define the completeness of injury. The age impairment scale A is defined as a complete injury with no motor or sensory function in the sacral segments. B is sensory incomplete where sensation but not motor function is present perianally and no motor function is preserved more than three levels below the motor level. This is to exclude that zone of partial preservation that is often a couple of segments wide. Age of C is motor incomplete in which there's sacral sparing, either sensory or motor, doesn't have to be both, but there is motor either present at the anal sphincter or more than three levels below the motor level. To differentiate between motor incomplete C and motor incomplete D, we have to look at whether the majority of key muscles below the neurologic level of injury, that single neurologic level, the highest level that everything is intact, if more than half of them have a grade of three or better than they are motor incomplete Asia D, if fewer than half of the key muscles below the neurologic level have a grade three or better than they are Asia C. It simply is a matter of counting those levels that have a grade three over five or better. If 50% or more of them are present, the individual has Asia D. If less than 50% of them are grade three or better, Asia C. Asia E is used to designate a normal exam and complete motor and sensory function as tested. However, they may still have spasticity, they may still have a neurogenic bladder and bowel dysfunction, but testing, you're not able to identify a sensory level nor a motor level. Let's talk about the clinical syndromes that are described in spinal cord injury. These have been described historically, but do have importance when identifying prognosis for recovery and clinical presentation. The central cord syndrome presents as weakness in the upper extremities greater than lower extremities. Oftentimes, this is found in elderly people who have cervical spondylosis, have a fall, hyperextension injury, are incomplete, but they seem to have more weakness in their arms and their hands especially. These people have a favorable outcome and prognosis for recovery if they're less than 50 years old. People who have this presentation oftentimes, although they have recovery, are not able to recover to the level of ambulation if they're older. Likewise, if their initial neuro exam is consistent with Asia D tetraplegia, they have a favorable diagnosis for recovery of ambulation. The pattern of recovery is typically the legs get stronger first, then bowel and bladder function returns, then proximal upper extremity function returns, finally, and most incompletely, the distal upper extremity hand function. So people with the central cord syndrome will often be ambulatory, but not be able to do fine motor functions with their hands. The Brown-Saquard syndrome is a presentation that takes into account the unique innervation and crossing pattern of the spinal cord. The clinical presentation is classically ipsilateral motor loss below the level of injury, ipsilateral loss of proprioception and vibration below the lesion, because the posterior columns and the corticospinal tracts travel on the same side as they enter the spinal cord until they get to the medulla. Then they cross, giving us the crossed brain to body. However, the spinal thalamic, which provides pain and temperature sensation, is lost contralateral to the injury. Spinal thalamic fibers enter the spinal cord and one or two segments from that point, they cross over and then ascend on the opposite side to the brain. So looking for a difference between sides in a person who seems to have motor loss more on one side than the other, checking the different sensory modalities, proprioception and vibration versus pain and temperature is very valuable. Light touch, however, is mediated through both the spinal thalamic tract and the posterior column and so you may not be able to differentiate this clinical presentation if you do not use the sharp dull discrimination and or vibration and proprioception. Now these individuals have a very good prognosis for walking as well as a good prognosis for bowel and bladder function. The third classical spinal cord syndrome is the anterior cord syndrome, in which there is some lesion affecting the anterior three-fifths of the spinal cord. This usually results in a flaccid paralysis because of loss of the anterior horn cells, loss of spinal thalamic function because these run anteriorly up and down the spinal cord, but preservation of posterior column functions, so proprioception, light touch, and vibration because these are carried through the posterior columns unaffected by the anterior cord syndrome. Now, most of the time, this is a vascular injury in which the anterior spinal artery is either injured or thrombosed either by a direct injury from retropulsion of the bone or disc, or more commonly, due to the loss of circulation to the spinal cord during aortic aneurysm surgeries with the occlusion of the great artery of the Damkowitz when there's inadequate collateral circulation to the spinal cord. The clinical presentation is typically a variable loss of motor and sensory, motor and pinprick sensation with a relative preservation of light touch and proprioception, most commonly in the thoracic and lumbar region, but can be seen at any level. These have a lower prognosis for motor recovery simply because of the ischemic injury to the long tracks of the spinal cord. The Conus medullaris syndrome is one in which the terminal segment of the spinal cord, the Conus medullaris, which ends at about the bony level of L1 and L2 vertebrae, if there is compression on this segment, you will see spastic sacral roots, but flaccid lumbar roots, which provides a unique presentation and functional impairment because the bladder, bowel, and sexual function should have reflex activity, including presence of a bobal cavernosus reflex, whereas their lower extremities may be a reflexic and show atrophy. That's why the rectal exam, testing for not only sensation and voluntary contraction, but also for reflexes, is essential in defining the type of injury. The cauda equina syndrome is an injury to the lower motor neurons below the Conus medullaris, essentially a polyridiculopathy of the lumbo and sacral roots. This clinical presentation is a flaccid sacral root function and flaccid lumbar root function. So there would be a negative boba cavernosus reflex and flaccid bladder, bowel, and sexual function, along with aryflexia and lower extremity atrophy. These clinical syndromes and all of the details regarding the neurologic examination can be found in the Asia Learning Center at these websites. Now let's talk about the acute management of spinal cord injury. With spinal cord injury, as in all acute trauma, the focus on an airway, circulation, and breathing is critical. The airway in 95% of people with C5 injury or higher will require some degree of mechanical ventilation initially. Many times that is initiated at the injury site. Other times it is when the person has begun fatiguing after they arrived to the hospital. Not all of these people will require lifelong ventilation, but many start that way. Blood pressure support is very important. Commonly, there is a cause of neurogenic shock in which there is, because of the spinal cord injury, there is a loss of vasoreflexes below the level of injury, which can lead to vasodilation and a loss of support return volume. There may be other causes of hypotension as well, and these need to be looked for, including hemorrhage. Fluids, often vasopressors, are needed, and the support is with a goal map of 85 millimeters of mercury for at least seven days. This is a higher map than you may find for typical ICU patients, simply because we're trying to maintain circulation to the spinal cord. Symptomatic bradycardia, due to a loss of sympathetic tone with the spinal cord and spine trauma, and excess vagus and parasympathetic activity, can require a pacemaker, either temporarily or permanently, especially in people with high tetraplegia. One of the great resources that we have in spinal cord injury medicine today is the Consortium for Spinal Cord Medicine, which has put out numerous clinical practice guidelines and continues to revise and update these. During this presentation, when you see a little booklet to the right of the screen, this is one of those consortium guidelines that provide evidence-based recommendations for the management of spinal cord injury. These can all be found at the website below at the Paralyzed Veterans of America website. When considering spine fractures, it's important to image the entire spine. Plain x-rays alone can miss a significant number of cervical spine fractures, and many people with fractures of the cervical spine also have thoracic or lumbar fractures. Therefore, CT for fracture screening of the entire spine is recommended for these trauma patients. If you're looking for soft tissue imaging, especially for presence of disc herniation or ligamentous instability, MRI is necessary. Many times, spinal instability could be missed if only a CT is being used because the spine may be in perfect alignment, but there may be evidence of soft tissue injury with ligamentous tear. Therefore, CT screening for fracture and MRI for soft tissue imaging are recommended. The goals of spine fracture management are basically three, to restore the spinal alignment, which in part decompresses the neural elements, and finally, to stabilize the spine. There are recommendations, evidence-based recommendations, that spine reduction, either closed or open, is indicated for cases of bilateral facet dislocation in incomplete spinal cord injury. This seems like a fairly small group because the evidence for different types of injury, different types of dislocation, and different degrees of completeness are hard to obtain through controlled studies. But in the cases of a bilateral facet dislocation, there is a significant step-off in impingement to the spinal canal, which necessitates reduction. And specifically, with incomplete injury, it may result in significant functional recovery. Decompression within 24 hours appears to have better neurologic outcomes compared to delayed surgery or conservative treatment. But again, this is soft data, and much of the goal of the early decompression is to attenuate the secondary injury mechanics. Although there's been continued work on the acute management of spine fractures, the amount of compression and the severity of the impact to the cord ultimately determines the severity of the neurologic injury. Spine stabilization is associated with less spinal deformity, but no difference in neurologic outcomes. So in the absence of realignment and decompression of the neural elements, simply stabilizing the spine does not appear to improve neurologic outcomes. And in people with complete injury, there does not appear to be a significant difference in much of the literature with stabilization alone. However, we all believe that decompression of the neural elements is important, and most neurosurgeons across the country do early decompression. I'd like to move on to some of the common injuries that we see associated with brain injury. One is traumatic brain injury. Spinal cord injury that affects the neck, especially in cases of polytrauma, has a high incidence of associated traumatic brain injury. In one study, 40% of polytrauma patients with a mid cervical C4 through C7 injury had an initial Glasgow coma scale of less than 13, suggesting a severe brain injury. These are more common with road traffic injuries, road traffic accidents, because of the energy involved in the trauma, as opposed to a fall from standing, and also cervical injuries, because if the neck is being hurt, the head being attached is likely being tossed and traumatized as well. Serial screening with the Galveston orientation and amnesia test, or GOAT, is effective in determining the post-traumatic, the presence of post-traumatic amnesia and the duration of PTA, which can offer prognosis in traumatic brain injury. GI complications are very common in the early stages of spinal cord injury. Nutrition is critical, and enteral feedings are always preferred to parenteral, as long as you have a functioning gut. And beginning feedings, tube feedings, within the first day or two, has an improved clinical outcome, shorter duration of ICU care. Gastric prophylaxis is recommended for ulcers for the first four weeks after spinal cord injury. Following the four weeks of injury, if there's no evidence of peptic ulcer disease, there is no indication for continued prophylaxis, but in the early stages, GI ulceration due to the severity of trauma and stress is common. Likewise, initiating bowel care as soon as feedings are initiated is important. The type of bowel care is determined based on the absence or presence of the bulbocavernosus reflex. Do they have an upper motor neuron or lower motor neuron bowel function? And these will be discussed a little later as well when we talk about long-term bowel issues. But don't wait until they have significant fecal impaction before starting a bowel program. Venous thrombosis causes a high degree of morbidity and mortality in acute spinal cord injury. And the Consortium for Spinal Cord Injury Medicine estimates that DVT, deep venous thrombosis, is present in anywhere from 14 to 100% of people with spinal cord injury. And this is based on the type of screening and the population. But pulmonary embolism is also very common. And in some studies can be as high as 90% with a fatal PE estimated at 5%. Thus, prevention of venous thrombosis and pulmonary embolism is important. Typically, we recommend mechanical devices, including compression hose and intermittent compression devices on the calves with a pharmacological option, most commonly now low molecular weight heparins, although in longer term use of vitamin K antagonists such as warfarin or the direct oral anticoagulants can be used for prophylaxis. In the acute phase, the recommendation is to start mechanical prophylaxis as soon as possible after the injury. Of course, if there's a long bone fracture in that limb, this not only increases the risk of thrombosis, but decreases the ability to mechanically prophylax and needs to be considered. Low molecular weight heparins should be used in acute care if there is no active bleeding. And as I'd mentioned, the combination of mechanical and pharmacologic prophylaxis is most effective. There's a recommendation against the use of low dose or adjusted dose heparin for prevention of DVT, unless low molecular weight heparins are not available. Likewise, the clinical practice guideline recommends against the routine use of inferior vena caval filters for prevention because of complications of thrombosis of the filter over time. In the presence of removable filters, this recommendation may be modified. In the post-acute and rehabilitation phase, the use of some anticoagulation is recommended during the entire phase of rehabilitation. Typically, they recommend eight weeks of prophylaxis in people with spinal cord injury who have limited mobility and are in rehab for longer than eight weeks, continuing through the entire rehabilitation program as is indicated. Likewise, there are indications to reinitiate prophylaxis when a person is admitted to the hospital for medical comorbidity because of the increased risk during that period of time as well. Pulmonary complications are very common in the acute phase. Respiratory failure due to a high level of injury and the loss of ventilation, pulmonary embolism, and pneumonia, all of which are preventable with proper care. The respiratory management following spinal cord injury is another clinical practice guideline put out by the consortium. They report studies of 40 to 70% of patients with tetraplegia developing atelectasis and pneumonia in the first weeks after spinal cord injury. This is primarily due to the loss of an active cough mechanism with severe paralysis. If you're not able to take deep breaths in and if you're not able to cough, airway clearance becomes a significant problem. Therefore, teaching assisted cough techniques, even in the ICU, can be very helpful because simply suctioning through a tracheostomy does not get clearance of the lower lungs and rarely affects clearance of the left lung field. The use of insufflation and exsufflation, a cough assist device, is beneficial as is percussion and postural drainage, which is really the only way that the left lower lobe can be drained adequately because of the anatomy of the left main bronchus. Bronchoscopy can be sometimes necessary and is oftentimes valuable for people with high levels of injury for secretion clearance to assist them in ventilator weaning. Pressure ulcers begin at the moment of injury and minimizing the time of a person may have on the backboard is critical. Using a pressure reduction mattress or overlay and using frequent skin inspections, regular turning, and proper positioning is essential. When a patient is in the ICU, these issues are often secondary to life-threatening complications such as hypotension and impaired ventilation. So these may be forgotten and overlooked, thus the high frequency of sacral pressure ulcers in the newly injured people with spinal cord injury. If we can prevent a pressure ulcer in the ICU, that will make a huge difference in their rehabilitation and time it takes to get home.

Neurologic Classification

Spinal Cord Injury

Sensory Exam

Motor Exam

Neurological Syndromes

Acute Management

Prevention Methods