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cervical, thoracic, and lumbar spine conditions:chapter 11 and 12. there are 26 bones in the spine. it is easy to remember the number of the boneswithin the sections of the spine as they are times we eat: 7, 12, and 5. there are seven cervical vertebrae, twelvethoracic vertebrae, five lumbar vertebrae, the sacrum is comprised of five fused vertebrae,and the coccyx contains four fused vertebrae. the first two vertebrae are a little differentthan the others: c1 is known as the atlas; c2 is known as the axis and has the dens,or small projection, which goes up inside of the body of the c1.

a fracture of c1 is known as a jefferson fracture. a jefferson fracture is a bone fracture ofthe anterior and posterior arches of the c1 vertebrae, although it may also appear asa three or two part fracture. the fracture may be a result from an axialload on the back of the head or hyper extension of the neck. this causes a posterior break and may be accompaniedby a break in other parts of the cervical spine as well. it is named after the british neurologista neurosurgeon, sir geoffrey jefferson, who reported four cases of a fracture 1920 inaddition to reviewing other cases that had

been previously reported. the vertebrae have distinct features whichseparate the different levels. cervical vertebrae have a small body: theyallow for the major movements of rotation, flexion, and extension. thoracic vertebrae have long transverse processes:they allow for the major movement of lateral flexion. the lumbar spines are the largest in the thickestand they allow for the major movements of flexion and extension. the sacrum is the large triangular shape bonewith the base directed upward.

it is comprised of five fused sacral vertebrae. the coccyx is a small irregular shape bone:the coccyx encompasses four underdeveloped vertebrae. the spine is made up of small bones that arestacked--along with disks--on top of one another. the spine has a natural curve to it. a healthy spine, when viewed from the side,has gentle curves. the curves help the spine absorb stress fromthe body movement and gravity. when they're viewed from the back, the spineshould run straight down the middle of the back.

the cervical vertebrae and lumbar spine havea natural interior convex curvature; the thoracic spine has a natural concave curvature whenviewed from the side. when abnormalities of the spine occur, thenatural curves of the spine are misaligned or exaggerated in certain areas; such as thatoccurs with lordosis, kyphosis, and scoliosis. an intervertebral disc lies between the adjacentvertebrae in the vertebral column. each disc forms a fibrocartilaginous jointor a synthesis joint and allows slight movement of the vertebrae. it acts like a ligament to hold the vertebraetogether. their role as shock absorbers in the spineis crucial.

discs consist of an outer fibrous ring, theannulus fibrosis, which surrounds the inner gel like center, which is called the nucleuspulposus. the annulus fibrosis consists several layersof laminae or fiber cartilage that are made up of both type i and type ii collagen. type i is concentrated towards the edge ofthe ring where it provides greater strength. the stiff laminae can withstand compressiveforces. the fibrous intervertebral disc contains thenucleus pulposus, and this helps to distribute pressure evenly across the disk. this prevents the development of stress contractionsin which could cause damage to the underlying

vertebrae or their endplates. the nucleus pulposus contains loose fibersuspending in the micro protein gel. the nucleus of a disc acts as a shock absorber,absorbing the impact of the body’s activities in keeping the two vertebrae separated. there are 23 discs in the human spine. six are in the neck, twelve are in the middle,and five are in the lower back. there is one disc between each pair of vertebrate,except for the first segment at the atlas. the atlas has a ring around it that’s roughlycone-shaped in extension of the axis. the axis acts is a post around which the atlascan rotate, allowing the next to swivel.

the spinal cord is a long, thin, tubular bundleof nervous tissue and support cells, which extend from the medulla oblongata in the brainstemto the lumbar region of the vertebral column. the brain and spinal cord together make upthe central nervous system or cns. the spinal cord begins at the occipital boneand extends down to the space between the first and second lumbar vertebrae; it doesnot extend the entire length of the vertebral column. it is around 45 centimeters in men and aroundforty three centimeters long in women. also, the spinal cord has a varying with rangingfrom 13 millimeters thick in the cervical and lumbar regions to 6.4 millimeters thickin the thoracic area.

the enclosing bony vertebral column protectsthe relatively shorter spinal cord. the spinal cord functions primarily in thetransmission of neuronal signals between the brain and the rest of the body, but can alsocontain neuronal circuits that can independently control numerous reflexes and central patterngenerators. the spinal cord has three major functions:as a conduit for motor information which travels down the spinal cord; as a conduit for sensoryinformation in the reverse direction; and finally is a center for coordinating certainreflexes. the cauda equina or latin for “horse's tail”is a bundle of spinal nerves and spinal nerve roots consisting of the second through fifthlumbar nerve pairs, the first through fifth

sacral nerve pairs, and the coccygeal nerve--all of which arise from the lumbar enlargement and the conus medullaris of the spinal cord. the nerves that compose the cauda equina innervatethe pelvic organs and lower limbs to include motor innervation of the hips, knees, ankles,feet, internal anal sphincter, and external anal sphincter. within the spine, there are 31 pairs of spinalnerve roots. each spinal nerve root separates into theventral root or anterior root, and the dorsal root or posterior route. the venture route or anterior route is theefferent motor route of the spinal nerve.

efferent signals travel away from the centralnervous system toward the peripheral effector organs-- mainly muscles and glands. the dorsal root or posterior route emergesfrom the spinal cord. the dorsal root transmits sensory informationforming the afferent sensory root of a spinal nerve. the afferent sensations arise from the nervecell in the body and carry nerve impulses from the sensation receptors towards the centralnervous system. in the nervous system, there's this closedloop system of sensation, decision, and reaction. this process is carried out through the activityof afferent neurons or sensory neurons, interneurons

and efferent neurons, or motor neurons. the motions that are available in the spineare rotation, flexion, extension, and lateral flexion or side bending. common mechanisms of injury for the spineare hyper extension (where the spine is forced backwards), hyper flexion (where the spineis forced forward), and axial loading, which is a sudden excessive compression which drivesthe weight to the body against the head. there are three main types of spinal curvaturedisorders including: kyphosis, which is characterized by an abnormally rounded upper back more than50 degrees of curvature; lordosis, also called swayback; the spine of the person with lordosiscurves significantly inward to the low back.

lordosis can also occur at the head with anincrease in the amount of lordosis. cervical lordosis results from forward headposture. scoliosis is a lateral curvature of the spine;i would encourage you to watch the quick video entitled “spinal conditions pop quiz”to see some additional examples of spinal abnormalities. especially with scoliosis, the first treatmentis usually bracing. the core is braced with hard plastic in theattempts to realign the spine and provide structural support. unfortunately, if the amount of curvatureis greater than degrees, often the only option

is a surgical intervention. it is common to fuse the spine to maintainthe structural support. however, in fusing the spine, patients oftenlose mobility. common cervical spine conditions include cervicalfractures, cervical dislocation, cervical strains, cervical sprains, cervical spinalstenosis, and brachial plexus injuries; all will be discussed further. cervical fractures are relatively uncommon,but when they occur they may result in permanent damage. the most common mechanism of injury is eitherfrom an axial load or hyper flexion, which

occurs frequently in gymnastics during tumblingand arial routines, ice hockey when the head is flexed and then driven into the board surroundingthe ice when a player is checked, diving, especially if the water is too shallow fora dive, football or rugby with either axial loading or head flex tackling. common signs and symptoms include neck pointtenderness, cervical spasms and pain, chest pain, weakness or numbness in the extremities,loss of bowel or bladder control. management of cervical fractures include:stabilizing the fracture with a hard cervical collar, early spine boarding to maintain stabilization,and activation of ems. cervical dislocations are not common thankfully,but happen more frequently than do fractures.

the mechanism of injury is hyper flexion orrotation. signs and symptoms are the same as those forfracture as is the management. the x-ray on this slide is an example of ac5-c6 dislocation. we can see where the bone should be articulated,but they have slipped off of each other. common fracture and dislocation managementincludes substantial bracing. the picture on the left is of a hard cervicalcollar which minimizes neck movement and allows tissue to heal. when a brace is not sufficient enough to reducemovement, a halo vest immobilizer may be used. halo mobilizations are commonly used for unstablefractures.

the cranial ring is secured to the patient’sskull using four metal pins. the ring attached by four metal bars to aplastic vest and is worn continuously. the estimated reduction and all cervical motionis over 90%. halo vest immobilizers provide distractingforces which can aid in stabilization and reducing the load of the head on the cervicalspine. cervical sprains are when the ligaments ofthe neck or damaged frequently through a whiplash or sudden snap of the head. signs and symptoms include pain, stiffness,and restriction in the range of motion. management and cervical sprains include priceor protection, rest, ice, compression, and

elevation; nsaids or non-steroidal, anti-inflammatorydrugs; stretching and strengthening. cervical strains occur when the muscles ortendons of the neck are damaged frequently through the same mechanism as results in cervicalsprains. the signs and symptoms may be very similarto springs as well, but may also include muscle spasms which may be easily palpated. we manage cervical strains the same way aswe do cervical sprains. this picture illustrates the mini cervicalligaments which could be injured during a sprain. it isn't important that you determine whichparticular ligament has been damaged as the

treatment is pretty much the same for allsprains. you do not need to memorize all the ligaments,but it is important to understand how complex the spine is and how delicate it can be. cervical spinal stenosis is the narrowingof the cervical canal in the neck. the spinal canal is the open area in the bonesor vertebrae that make up the spinal column. the spinal cord is a collection of nervesthat run through the spinal canal from the base of the brain to the lower back; whenthe spinal column narrows, the spinal cord may be pinched or impinged. common signs and symptoms include transientquadriplegia, which means they have a paralysis

of all four extremities that comes and goes,burning, tingling, numbness, weakness, and symptoms may disappear after 10 to 15minutes. an mri is often needed to determine the managementfor cervical spine stenosis. if spinal stenosis is discovered, an athletemay need to discontinue participation, especially if they are participating in a contact sportsuch as lacrosse, rugby, or american football. brachial plexus injuries are often also calledburners or stingers. the mechanism of injury is either a stretchor a compression of the nerve bundle. signs and symptoms include burning, tingling,temporary pain, numbness, and sometimes weakness to the arm.

they may describe that they have a quote onquote “dead arm”. repeated injuries can result in permanentneurological damage to the upper extremity. management is removing the athlete from activityand rest. thoracic spine conditions include thoraciccontusions, sprains and strains, and thoracic spinal fractures. thoracic contusions sprains and strains arerare; there are most commonly seen in car accidents from the chest hitting the steeringwheel. if there are bruises on the thoracic cavity,it is imperative to also examine for internal organ injury as well.

when ribs break, they can puncture the lungsor the heart which may result in catastrophic injury. signs and symptoms include ecchymosis, swelling,and decreased range of motion; the person may also complain of difficulty breathing. management of thoracic contusions strainsand sprains includes immediate referral. thoracic fractures are rare, but can happenin high-impact sports such as skiing, tobogganing, skydiving, automobile racing, and rodeo. wedge fractures are the most common typesof fracture. a wedge fracture is a compressive fractureon the interior surface of the vertebrae;

the vertebrae then collapses anteriorly. if this fracture isn't bad enough, the spinousprocess may also open up which results in a chance fracture. common lumbar spine conditions that will bediscussed are lumbar contusions strains and sprains, lumber fractures, spondylolysis,spondylolisthesis, facet joint dysfunction, disc pathology, sciatica, and si joint dysfunction. lumbar pain is very common: an estimated 75-80%of the population experiences low back pain resulting from mechanical injury to muscles,ligaments, and connective tissue. approximately 30% of children suffer fromlow back pain.

poor posture including excessive lumbar lordosiscurvature and weak abdominal muscles are frequently associated with low back pain. some people refer to this as the “butt out,gut out” position which is exhibited in the top picture. signs and symptoms include ecchymosis, swelling,decrease in range of motion, and possible radiating pain, usually into the lower extremities. management of lumbar contusions strains andsprains include controlling the pain and hemorrhage, and then stretching and strengthening of tissue. lumbar fractures like the thoracic fracturesare rare, but they can happen in contact sports

such as football, rugby, soccer, basketball,hockey, and lacrosse. fractures often lead to other soft tissueinjuries. the most common type of fracture in the lumbarspine is a compression fracture and also what are known as spondys. a spondylolysis is a stress fracture of thepars interarticularis. they are common in adolescents and athletesthat are still developing. the fracture of the pars interarticulariscan either be bilateral (on both sides) or unilateral (on only one side) of the vertebrae. the most common mechanism of injury occursas a result of repetitive hyperextension.

this injury is known as a collared scottydog fracture as it resembles a scotty dog wearing a collar when the fracture is x-rayedsuch as that in the picture. the signs and symptoms which are common toa spondylolysis are pain in the lumbar spine possibly radiating into the buttocks and thighs,muscle spasm, pain with extension, management includes x-ray to identify the fracture, possiblebracing or bed rest, and eventually rehabilitation focusing on core exercises. a spondylolisthesis is more severe versionof a spondylolysis: this includes a bilateral pars interarticularis fracture. this injury may also include anterior displacementof the affected vertebrae.

the signs and symptoms of a spondylolisthesisare the same as they are for a spondylolysis; however this injury may also include a stepoff deformity which means when the spinous processes are palpated, one spine may be displacedanteriorly and it may feel like the finger slips into the spine. conservative treatment is much the same asit is for a spondylolysis. the spondylolisthesis happens most frequentlyat the l5 level as it sits precariously on the sacrum. a hangman's fracture is a specific type ofspondylolisthesis where the second cervical vertebrae or c2 is displaced anteriorly relativeto the c3 vertebrae due to fractures of the

c2’s vertebra pedicles. treatment for the spondy’s include conservativeor non-surgical options like bracing, with pictures on the left given as examples. more invasive management may include surgicalfixation and intervention. facet joint dysfunction accounts for nearly45% of all chronic low back pain. facet joint dysfunction is a broad term, butmay include such maladies as facet joint syndrome or inflammation of the facet joints, arthritisor degeneration of the facet joints, or dislocation and subluxation of the facet joints, whichmight result in locking of the joint causing hypermobility or decrease in mobility.

signs and symptoms of facet joint dysfunctioninclude: nonspecific low back, hip or buttock pain; flattening of the lumbar lordosis curve;increase pain with rotation, extension, and lateral flexion towards the involves side;and management strategy should include extra hour mri to determine injury anesthetic injectionto the facet joint, rest, nsaids, and core strengthening exercises. a herniated disc occurs when the gel-likecenter of the disk ruptures through the weak area on the tough outer wall; similar to thefilling being squeezed out of a jelly doughnut. back or leg pain, numbness, or tingling mayresult when the disc material touches or compresses a spinal nerve.

treatment with rest, pain medications, spinalinjections, and physical therapy is the first step to recovery. most people improve in approximately six weeksand return to normal activity. if symptoms continued, surgery may be recommended. there are four different levels of disc herniation:a protrusion or bulging occurs when some eccentric accumulation of the nucleus with slight deformityof the annulus; a prolapse is when the nucleus moves through the annulus; an extrusion occurswhen the nucleolus moves into the spinal cord, and during sequestration, the nucleus separatesfrom the disc itself. disc herniation is the most common at thel4, l5 level.

disk pathology signs and symptoms includesensory and motor deficits, alteration in tendon, reflex sharp pain that shoots downto the lower extremity, muscle spasm, and increased pain with coughing and sneezing. conservative management includes price andrehabilitation as the first course of treatment. if that is ineffective, then possibly surgeryis warranted. sciatica is the general term for all low backpain. the sciatic nerve is the largest in the body. sciatica results from irritation of the sacralnerve, herniated discs, spinal stenosis, and possibly piriformis syndrome.

piriformis syndrome is an uncommon neuromusculardisorder that is caused when the piriformis muscle compresses the sciatic nerve. the piriformis muscle is a flat band likemuscle located in the buttocks near the top of the hip joint. this muscle is important in lower body movementbecause it stabilizes the hip joint and lifts and rotates the thigh away from the body. this enables us to walk, shift our weightfrom one foot to another, and maintain balance. it is also used in sports that involve liftingand rotating the thighs, and short for almost every motion of the hip and legs.

the sciatic nerve is a thick, long nerve inthe body. it passes along side or goes through the piriformismuscle and then travels down the back of the leg eventually branching off into smallernerves that in the feet. nerve compression can be caused by spasm ofthe piriformis muscle. piriformis syndrome usually starts with painand tingling or numbness in the buttocks. it can be severe and extend down the lengthof the sciatic nerve called sciatica. the pain is due to the piriformis muscle compressingon the sciatic nerve such as while sitting in a car seat or running. pain may also be triggered while climbingstairs applying firm direct pressure over

the piriformis muscle or by sitting for longperiods of time. most cases of sciatica however, are not dueto piriformis syndrome. stretching may relieve some of these signsand symptoms. sacroiliac joint dysfunction is due to a lackof excessive mobility at the sacral iliac joint. it is common during pregnancy, especiallycloser to labor. signs and symptoms of si joint dysfunctioninclude unilateral pain or one side pain. management may include an si belt which willhelp support the joint, rehabilitation with a focus on core exercises, injections, orpossibly surgery.

protective equipment may assist in decreasingspinal conditions including shoulder pads, neck collars, weight belts, and si belts. also focusing on physical conditioning includingstretching and strengthening muscles and teaching proper posture and skill techniques, may assistin the prevention of spinal conditions. evaluating patients for poor posture duringvarious activities including: walking, sitting, and sleeping. in sports that involve tackling, do not allowplayers to spear or lead with the top of their head. when a football player tackles, they shouldtackle with their head up so they can read

the numbers or lettering on the jersey ofthe player they are tackling. also teaching proper lifting techniques, especiallywhen heavy weight is being utilized, can help decrease the incidence of spinal conditions.

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