Gross Anatomy of the Spinal Cord PDF
Document Details
Uploaded by InfallibleChrysoberyl
Cebu Doctors' University
Tags
Summary
This document provides an overview of the gross anatomy of the spinal cord, focusing on the gray matter. It details the structure of the gray matter, including the anterior, posterior, and lateral columns, and the nerve cell groups within them. The document also discusses the relationship between the size of the gray matter and the amount of muscle innervated. It is a useful resource for learning about spinal cord anatomy.
Full Transcript
GROSS ANATOMY OF THE SPINAL CORD ANATOMY OF THE GRAY MATTER he spinal cord is roughlycylindrical in shape. T...
GROSS ANATOMY OF THE SPINAL CORD ANATOMY OF THE GRAY MATTER he spinal cord is roughlycylindrical in shape. T he spinal cord is composed of aninner core of gray T Itbegins superiorly at the foramen magnumin the matter, which is surrounded by an outer covering of white matter. skull, where it is continuous with the medulla oblongata On cross section, the gray matter is seen as an of the brain, and it terminatesinferiorly in the adult at H-shaped pillar with anterior and posterior gray the level of the lower border of the first lumbar columns, or horns, united by a thin gray commissure vertebra. containing the small central canal. Thus it occupies theupper two thirds of the vertebral A small lateral gray column or horn is present in the canal of the vertebral columnand is surrounded by thoracic & upper lumbar segments of the cord. thethree meninges, the dura mater, the arachnoid Theamount of gray matter presentat any given level mater and the pia mater. of the spinal cord is related to theamount of muscle Further protection is provided by thecerebrospinal innervated at that level. fluid, which surrounds the spinal cord in the Thus, its size isgreatest within the cervical & subarachnoid space. lumbosacral enlargements of the cord, which In the cervical region, where it gives origin to the innervate the muscles of the upper & lower limbs, lumbosacral plexus, the spinal cord is fusiformly respectively. enlarged; the enlargements are referred to as the cervical & lumbar enlargements. Nerve Cell Groups in the Anterior Gray Column Inferiorly, the spinal cordtapers off into the conus ost nerve cells arelarge & multipolar,and their M medullaris, from the apex of which a prolongation of axons pass out in the anterior roots of the spinal the pia mater, the filum terminale, descends to be nerves asalpha efferents, which innervate skeletal attached to the posterior surface of the coccyx. muscles. The cord possesses, in the midline anteriorly, adeep Thesmaller nerve cellsare alsomultipolarand the longitudinal fissure, theanterior median fissure, axons of many of these pass out in the roots of the spinal nerves asgamma efferents, which innervate and on the posterior surface, a shallow furrow, the the intrafusal muscle fibers of neuromuscular spindles. posterior median sulcus. Along the entire length of the spinal cord are attached 31 pairs of spinal nervesby the anterior or motor Nerve Cell Groups in the Posterior Gray Column roots and the posterior or sensory roots. Each root is attached to the cord by a series of rootlets, here are four nerve cell groups of the posterior gray T which extend the whole length of the corresponding column, two that extend throughout the length of the segment of the cord. cord and two that are restricted to the thoracic & lumbar Each posterior nerve root possesses aposterior root segments. Thesubstantia gelatinosagroup is situated at the ganglion, the cells of which give rise to peripheral & apexof the posterior gray column throughout the central fibers. length of the spinal cord. Itreceives afferent fibersconcerned withpain, temperature & touch sensationfrom the posterior root. Furthermore, it receives input from descending fibers from supraspinal levels. It is believed that the inputs of the sensations of pain & temperature are modified by excitatory or inhibitory information from other sensory inputs and by information from the cerebral cortex. Thenucleus propriusis a group of large nerve cells situated anterior to the substantia gelatinosa throughout the spinal cord. This nucleus constitutes the main bulk of cells present in the posterior gray column and receives fibers from the posterior white column that are associated with the senses of position & movement (proprioception), two-point discrimination, and vibration. Thenucleus dorsalis(Clark's column)is a group of nerve cells situated at the base of the posterior gray column and extending fromC8 caudally to L3 or L4 segment. Most of the cells are comparatively large and are associated withproprioceptive endings (neuromuscular spindles & tendon spindles). Thevisceral afferent nucleusis a group of nerve cells of medium size situated lateral to the nucleus dorsalis; it extends from T1 to L3 segment of the spinal cord. It is believed to be associated withreceiving visceral afferent information. B3M3 Case 1 1of 8 Nerve Cell Groups in the Lateral Gray Column heintermediolateral groupof cells forms the small T lateral gray column, which extends fromT1 to L2/L3 segment of the spinal cord. The cells are relatively small & give rise to preganglionic sympathetic fibers. A similar group of cells, found in theS2 to S4 segments of the spinal cord give rise to preganglionic parasympathetic fibers. Gray Commissure Intransverse sectionsof the spinal cord, the anterior & posterior gray columns on each side are connected by atransverse gray commissure, so that the gray matter resembles the letter H. In the center of the gray commissure is situated the HISTOLOGY OF THE SPINAL CORD central canal. scending and descending fibersoccupying A particular regions of the white matter of the spinal cord are organized into more or less distinct bundles. Fiber bundles having the same, or similar origin, course and termination are known astracts or funiculi. The white matter of the spinal cord is divided into three paired funiculi:posterior, lateral and anterior. Theposterior funiculuslies between the dorsal horn and the posterior median septum. Inupper thoracic and cervical regions,a small posterior intermediate septum divides each posterior funiculus into two white columns. Thelateral funiculuslies between the dorsal root entry zone and the site where ventral root fibers emerge from the spinal cord. Theanterior funiculuslies between the anterior median fissure and the emerging ventral root filaments. Theposterior funiculusis the largest and is composed almost exclusively oflong ascendingand short descending fibersthat arise from cells in spinal ganglia. ASCENDING TRACTS AND THEIR FUNCTIONS ainful & thermal sensationsascend in thelateral P ANATOMY OF THE WHITE MATTER spinothalamic tract Light(crude)touchandpressureascend in the hewhite matter, for purposes of description, may be T anterior spinothalamic tract. divided intoanterior, lateral & posterior white Discriminative touch(the ability to localize columns or funiculi. accurately the area of the body touched and also to be Theanterior columnon each side lies between the aware that two points are touched simultaneously, midline & the point of emergence of the anterior nerve even though they are close together) ascends in the roots; thelateral columnlies between the emergence posterior white columns. of the anterior nerve roots and the entry of the posterior Ascending in the posterior white columns is nerve roots; theposterior columnlies between the information from muscles & joints pertaining to movement and position of different parts of the body. entry of the posterior nerve roots and the midline. In addition, vibratory sensations ascend in the For purposes of description, the spinal tracts are posterior white column. divided intoascending, descending, and Unconscious information from muscles, joints, the skin intersegmental tracts, and their relative positionsin and subcutaneous tissue reaches the cerebellum by the white matter are described below. way of theanterior & posterior spinocerebellar A simplified diagram shows the general arrangement of tracts and by the cuneocerebellar tract. the major tracts. Pain, thermal & tactile information is passed to the superior colliculusof the midbrain through the spinotectal tractfor the purpose of spinovisual reflexes. Thespinoreticular tractprovides a pathway from the muscles, joints & skin to the reticular formation. Thespino-olivary tractprovides an indirect pathway for further afferent information to reach the cerebellum. B3M3 Case 1 2of 8 LIGHT AND PRESSURE PATHWAY It is theaxons of the second-order neuronwhich cross very obliquely to the opposite side in the anterior gray and white commissures within several spinal segments and ascend in the opposite anterolateral white column as theanterior spinothalamic tract. PAIN AND TEMPERATURE PATHWAY DISCRIMINATIVE, VIBRATORY SENSE, AND CONSCIOUS MUSCLE JOINT SENSE PATHWAY It is theaxons of the second-order neuronsin the nuclei gracilis & cuneatusin the midbrain, called the internal arcuate fibers, which sweep anteromedially around the central gray matter and cross the median plane, decussating with corresponding fibers of the opposite side in thesensory decussation. The fibers then ascend as a single compact bundle, themedial lemniscus,through the medulla oblongata, pons & midbrain. It is theaxons of the second-order neuronwhich cross obliquely to the opposite side in the anterior gray and white commissures within one spinal segment and ascend in the contralateral white column as thelateral spinothalamic tract. B3M3 Case 1 3of 8 DESCENDING TRACTS AND THEIR FUNCTIONS Pathway of the Corticospinal Tract from the Cerebral Cortex to the Effector Skeletal Muscles Corticospinal Tract he corticospinal tracts are the pathways T concerned withvoluntary, discrete, skilled movements, especially those of the distal partsof the limbs. Reticulospinal Tract he reticulospinal tracts may facilitate or inhibit T the activity of thealpha & gamma motor neuronsin the anterior gray columns and may, therefore,facilitate or inhibit voluntary movement or reflex activity. Tectospinal Tract he tectospinal tract is concerned withreflex T postural movements in response to visual stimuli. Those fibers that are associated with the sympathetic neurons in the lateral gray column are concerned with the pupillodilatation reflex in ote that thecorticospinal tracts are believed to N response to darkness. control the prime mover muscles(especially the Rubrospinal Tract highly skilled movements), whereas the other he rubrospinal tract acts on both the alpha & T descending tracts are important in controlling the simple gamma motor neurons in the anterior gray basic movements. columns and facilitates theactivity of flexor For simplicity, the internuncial neurons are omitted from muscles and inhibits the activity of extensor this table. or antigravity muscles. At the junction of the medulla oblongata & the spinal cord, most of the fibers of the corticospinal pathway cross the midline at the decussation of the pyramids Vestibulospinal Tract and enter the lateral white column of the spinal cord to he vestibulospinal tract, by acting on the motor T form the lateral corticospinal tract. neurons in the anterior gray column, facilitates the The remaining fibers do not cross in the decussation, activity of extensor muscles,inhibits the activity of but descend in the anterior white column of the spinal the flexor muscles, and is concerned with the cord as the anterior corticospinal tract. postural activity associated with balance. These fibers eventually cross the midline and terminate The descending autonomic fibers are concerned with in the anterior gray column of the spinal cord segments thecontrol of visceral activity. in the cervical & upper thoracic region. B3M3 Case 1 4of 8 Reflex and the Reflex Arc Eliciting Deep Tendon Reflexes reflexmay be defined as an involuntary A liciting deep tendon reflexes involves a series of E response to a stimulus. It depends on the integrity examiner skills. of the reflex arc. In its simplest form, the reflex arc Be sure to select a properly weighed reflex hammer. consists of the following anatomical structures: Learn when to use either the pointed or the flat end ○ a receptor organ of the hammer. ○ an afferent neuron Thepointed end is useful for striking small areas, ○ an effector neuron such as your finger as it overlies the biceps tendon; ○ an effector organ theflat end causes less discomfort when you test Such areflex arcinvolving only one synapse is the brachioradialis reflex. referred to as a monosynaptic reflex arc. Reflexes are graded on a0 to 4+ scale ○ 0 - no response In the spinal cord, reflex arcs play an important role ○ 1+ - somewhat diminished; low normal in maintaining muscle tone, which is the basis for ○ 2+ - average: normal body posture ○ 3+ - brisker than average; possibly but not necessarily indicative of disease ○ 4+ - very brisk, hyperactive, with clonus (rhythmic oscillations between flexion & extension) Signs Found in Upper Motor Neuron Lesions esions of thecorticospinal tracts(pyramidal L tracts) ○ The Babinski sign is present. ○ The superficial abdominal reflexes are absent. ○ The cremasteric reflex is absent. ○ here is loss of performance of fine skilled voluntary movements, especially at the distal end of the limbs. Lesions of thedescending tractsother than the corticospinal tract (extrapyramidal tracts) ○ Severe paralysis with little or no muscle atrophy. ○ Spasticity or hypertonicity of the muscles. ○ Exaggerated deep muscle reflexes and clonus may be present in the flexors of the fingers, the quadriceps femoris & the Assessment of the Motor System calf muscles. s you assess the motor system,focus on body A ○ Clasp-knife reaction is present. When position, involuntary movements, characteristics passive movement of a joint is attempted, of the muscles(bulk, tone & strength) and there is resistance owing to spasticity of coordination. the muscles. The muscles, on stretching, Muscular strength is graded on a0 to 5 scale: suddenly give way due to neurotendinous ○ 0 - no muscular contraction is detected organ-mediated inhibition. ○ 1 - a barely detectable flicker or trace of contraction Signs Found in Lower Motor Neuron Lesion ○ 2 - active movement of the body part with It includes: gravity eliminated ○ Flaccid paralysis of muscles supplied. ○ 3 - active movement against gravity ○ Atrophy of muscles supplied. ○ 4 - active movement against ○ Loss of reflexes of muscles supplied. ○ gravity & some resistance ○ Muscular fasciculation (twitching of ○ 5 - active movement against full resistance muscles), seen only when there is slow without evident fatigue; this is normal muscle destruction of the lower motor neuron cell. strength ○ Muscular contracture. This is a shortening Evaluation of the Sensory System of the paralyzed muscle. ○ Reaction of degeneration. o evaluate the sensory system, you will test T Normally innervated muscles respond to stimulation several kinds of sensation: ○ pain & temperature (spinothalamic tracts) by the application offaradic (interrupted) current; ○ position & vibration (posterior columns) and the contraction continues as long as the current ○ light touch (both of these pathways) is passing or direct current causes contraction only ○ discriminative sensations, which depend on when the current is turned on or turned off. some of the above sensations but also When the lower motor neuron is cut, amuscle will involve the cortex no longer respond to interrupted electrical stimulation 7 days after nerve section, although it still will respond to direct current. B3M3 Case 1 5of 8 fter10 days, the response to direct current also A or the emergency physician, the cell origin of the F ceases. This change in muscle response to tumor is less of a concern than the consequent electrical stimulation is known as thereaction of syndromes of spinal cord dysfunction. degeneration. Spinal Shock Syndrome Epidemiology his clinical condition followsacute severe T nited States - Metastatic lesions that involve the U damage to the spinal cord. spinal cord affect about5-10% of patients with All cord functions below the level of the lesion cancer. become depressed or lost and sensory impairment Approximately15%of all primary CNS lesions arise and a flaccid paralysis occur. from the spinal cord, with an estimated incidence rate Thesegmental spinal reflexesare depressed due of0.5-2.5 cases per 100,000 population. to the removal of influences from the higher centers International - the international incidence rate that are mediated through the corticospinal, parallels that of the United States. reticulospinal, tectospinal, rubrospinal and vestibulospinal tracts. Mortality/Morbidity Spinal shock, especially when the lesion is at a ost primary spinal cord cancers do not disseminate M high level of the cord, may also cause severe widely through the CNS or body. hypotension from loss of sympathetic vasomotor Consequent disability relates to the degree of cord tone. impairment and anatomic level of cord injury. In most patients, theshock persists for less than Metastatic tumorsthat cause epidural cord 24 hours,whereas in others, it may persist for as compression and dysfunction are themost common long as1 to 4 weeks. causes of oncologic CNS injury. Mortality correlates with the prognosis of primary As the shock diminishes, the neurons regain their cancer. excitability and the effects of the upper motor The severity of spinal cord compromise secondary to neuron loss on the segments of the cord below the a tumor spans a wide range. lesion, for example, spasticity & exaggerated Initially, symptoms may be limited to pain or minor reflexes, will make their appearance. sensory or motor disturbance. As the compression progresses, neurologic nal Sphincter Reflex A abnormalities become more pronounced, advancing (Bulbocavernous Reflex) to disability. Partial cord compression, such as he presence of spinal shock can be determined by T Brown-Séquard syndrome, may evolve. testing for the activity of the anal sphincter In the advanced stage of compression, complete reflex. transverse sensory and motor paralysis with bowel The reflex can be initiated by placing agloved and bladder incontinence occurs. finger in the anal canal and stimulating the anal The disability of the patient at the initiation of therapy sphincter to contract by squeezing the glans serves as the best predictor of ultimate disability in penis or clitoris, or gently tugging on an inserted patients with epidural cord compression. Foley catheter. Early detection of cord compression and early Anabsent anal reflexwould indicate theexistence intervention is the goal. of spinal shock. A cord lesion involving the sacral segments of the Sex cord would nullify the test, since the neurons giving slightmale predominance exists for primary A rise to the inferior hemorrhoidal nerve to theanal spinal cord tumors. sphincter (S2-S4) would be nonfunctioning Symptomatic hemangiomasoccur most frequently in thethoracic region of teenage girls. Epidemiology, Pathophysiology, Diagnosis, Prognosis, Management and Prevention of Spinal Cord Tumors Age eoplastic disease that involves the spine with N eople older than 50 years are more likely to P spinal cord compression may be devastating if experience back pain secondary to a metastatic unrecognized. tumor. Primary spinal cord tumors arise from the different The incidence of primary spinal cord tumors peaks elements of the CNS, includingneurons, in peopleaged 30-50 years. supporting glial cells, and meninges. Certain CNS tumors, such as neuroblastoma, occur Anatomically, neoplasms of the spinal cord may be almost solely in pediatric patients. classified according to the compartment of origin, Clinical syndromes produced by intramedullary either intramedullary (inside the cord) or tumors vary depending on the age of the individual. extramedullary (outside the cord). In children, gait disturbances prevail, with pain Additionally, cancers that metastasize to the reported infrequently. vertebrae or surrounding tissues frequently cause Spinal cord neoplasms may manifest asscoliosis spinal cord compression. or torticollisin younger patients. Metastatic lesions are featured in this discussion Painis the most common early complaint of adult since they cause85% of the cases of neoplastic patients with spinal cord neoplasms, followed by the spinal cord compression. The clinical presentation tends to be insidious progression of spinal cord dysfunction. indistinguishable from that of primary cancers of the spine. B3M3 Case 1 6of 8 Pathophysiology lue in establishing the diagnosis. c etastatic spinal cord compression usually follows M Gradually worsening back pain is the classic initial hematogenous dissemination of malignant feature of the spinal cord. cells to the vertebral bodies, with subsequent Neoplastic disease in about 90% of adult patients. expansion into the epidural space. Pain often precedes other symptoms associated with Spread into the epidural space may occur by spinal cord compression by 2-4 months. means of tumor extension through the Discomfort may be radicular, localized to the back, or intervertebral foramina or hematogenous spread by both. way of theBatson venous plexus. Radicular painsuggests nerve root impingement and Most frequently,metastatic seeding appears in may be exacerbated with movement or straining. the thoracic spine(accounting for about 70% of Once symptoms other than pain appear, symptom cases), with thelumbar spinebeing the next most progression may be rapid. involved site (20% of cases). Pain from vertebral metastasis may worsen with a Thecervical spineis affected in approximately recumbent position in contrast to back pain from 10% of cases. degenerative joint disease, which may improve with a Multiple spinal levels are affected in about 30% of recumbent position. patients. Sensory or motor symptoms that may be referred to Systemic cancers with a tendency for spinal cord the cord includelimb paresthesias and weakness. metastasis include the following: breast, prostate, Emergence of leg weakness, paresthesias in the renal, or lung neoplasms; lymphoma; sarcoma; and lower extremities, and/or bowel or bladder dysfunction multiple myeloma. in patients with a history of cancer should evoke Gastrointestinal and pelvic malignanciestend to immediate concern for cord compression. affect thelumbosacral spine; lung and breast cancersare more likely to affect thethoracic Paraplegia and bowel or bladder disturbances (eg, spine. constipation, urinary hesitancy, retention, Metastases to the substance of the cord incontinence) are usually late findings except in conus (intramedullary) are relatively rare. medullaris syndrome, in which sphincter dysfunction Signs and symptoms tend to simulate those of and saddle anesthesia may emerge early in the epidural compression; however, the associated course. motor weakness is more likely to be unilateral. Findings on physical examination correspond to the Principles of treating intramedullary cancer are location of the tumor, degree of cord similar to those for epidural spinal cord impingement, and duration. compression. Spasticity, hyperreflexia, and loss of pinprick, Leptomeningeal metastasesspread by means of temperature, position, and vibratory sensation may diffuse ormultifocal seedingof the meninges occur early. from systemic cancer (eg, lung or breast cancer, Percussion tenderness over the affected spinal region melanoma, lymphoma). may be present. Consequent signs and symptoms may be referable Deep-tendon reflexes may be initially hypoactive or to thespine or spinal cord. absent. TheBabinski sign(upward movement of the Evidence of spinal compromise may include lower toe in response to plantar stimulation) may be absent extremity weakness, paresthesias, reflex early in the course of compression. asymmetry, and spinal pain. Pain that progresses down the asymptomatic (or less Most primaryintramedullary spinal cord tumors symptomatic) limb caused by straight-leg raising may are astrocytomas or ependymomas. suggestcord compression. Intradural extramedullary tumorsinclude schwannomas, neurofibromas, and meningiomas Valsalva maneuvers, such as coughing, sneezing, or that affect the paravertebral area and may spread straining, may exacerbate radicular back pain from and compress the cord through expansion. cord compression. Additionally, an enlarging cancerous lymph node Late signs include demonstrable weakness, clear may compress the cord. sensory loss, bilateral Babinski signs, and decreased Hemangiomas(benign tumors of the blood anal sphincter tone and bulbocavernosus reflex. vessels) are usually discovered incidentally and As spinal cord compromise advances, hyperreflexia usually do not produce symptoms. However, symptoms emerge if pathologic vertebral fractures and Babinski reflexes are typically present. or epidural extension occurs. Lax rectal sphincter toneis alate signof spinal Nerve tracts most vulnerable tomechanical cord dysfunction. pressureinclude thecorticospinal and Almost one half of patients with a tumor and spinocerebellar tractsand the posterior spinal subsequent spinal cord compression have some columns. paresis, with as many as 15% of patients being Additionally neoplasms may compromise the paraplegic at the time of diagnosis. vascular supply, causing edema or ischemia. Less frequently, tumors may induce cyst formation or Coexisting emergence of lower extremity weakness cavitation within the spinal cord. and sensory loss may cause ataxia or a gait disturbance Clinical Presentation (History) TheLhermitte sign(ie, sudden, electric shock-like arly symptoms of spinal cord neoplasms are E pain with neck flexion) indicates meningeal often nonspecific and include local pain or irritation. stiffness. Nuchal rigidityoccurs in about 10% of patients A history of malignancy may provide the pivotal withleptomeningeal metastasis. B3M3 Case 1 7of 8 artial cord disorders, such asBrown-Séquard P Management syndrome(contralateral motor and sensory mergency Department Care:spinal cord E deficits), arise from lateral spinal cord compression. compression secondary to cancer is an Lesions of the cauda equina and the termination of emergencythat requires rapid diagnosis and the spinal cord may cause a combination of upper treatment to prevent permanent complications. motor neuron and lower motor neuron signs. Even when a cure is not possible,timely diagnosis Tumors in the region of the foramen magnum may andtreatment may improve the patient's quality produce quadriparesis and simulate other causes of oflife. diffuse weakness. Consider administeringsteroidsto patients who are If a cervical intramedullarytumor or syrinx(cavity) thought to have cord compression secondary toa is present, the unusual clinical picture of isolated neoplasm. sensory loss may be present in the upper Chemotherapy has a limited role in treating spinal extremities. cord compression and should be administered at thediscretion of the consultant. Diagnosis Radiation therapy:Radiation Treatment To Areas Of RI of the affected area provides the best M Tumor compression should be pursued after definition of spinal lesionsand is theprocedure appropriate imaging and consultation. of choice. Cord compression from an epidural tumor isconsidered With MRI, the entire spine may be visualized rapidly one of the few emergencies in radiation oncology. (sagittal images), and images may be obtained in Spinal cord toleranceto radiation depends on the multiple planes for best definition of the lesion, fraction size and cumulative dose. vertebrae, epidural space, and spinal cord. Neurosurgeons traditionally manage spinal cord Roughlyone thirdof people with spinal epidural compression and dysfunction; however, local practices metastases have multiple spinal metastases. may vary. MRI can usually be used to differentiate a collapsed Oncology, neurology, and radiation oncology staff may vertebra secondary to osteoporosisor trauma be involved in some circumstances. from malignant disease. Further inpatient care may includesteroid MRI of plain film above showing intrusion of tumor administration, chemotherapy,or surgery orderedat and vertebral collapse into spinal canal. the discretion of attending physicians. The intervertebral space is usually not involved in Surgical decompressionprovides immediate relief of tumors of the spine. When the disk space is compression but may contribute to spinal mechanical obliterated, infection is more likely. instability. Diffusion-weighted MR imagingmay be useful in However, if instability is present from tumor destruction, evaluation of epidural neoplastic lesions. surgery may be necessary for stabilization. If MRI cannot be performed, consult a qualified Recent research suggests that acombination of radiologist or oncologist about other imaging surgical decompression and radiation may be more options (eg, intrathecal contrast-enhanced effective than radiotherapy alone. This is an areaof myelography, CT-scan, nuclear medicine bone active investigation. scanning). Treatment is individualized and depends ontumor Plain radiographsmay reveal bony destruction type, degree of neurologic function, and other (osteolytic or osteoblastic lesions), vertebral factors. collapse or subluxation, or calcification (associated with a meningioma). Prognosis Roughly 50% of the bone must be destroyed to be otential complications of spinal cord neoplasms include P visible on plain films. the following: Patient withmetastatic breast cancer; plain ○ Paraplegia radiograph showsL4 vertebral collapse. ○ Quadriplegia Conventional radiographsdonotprovide ○ Urinary tract infections information about spinal cord structure or ○ Soft-tissue damage compression. ○ Respiratory complications Changes are demonstrated on plain films in about The prognosis forrecovery of neurologic deficits 80% of patients with spinal cord tumors. secondary to spinal cord compression isrelated to the Conversely, findings on plain films are falsely duration and severity of the impairment at the start negative in about 20% of cases. of treatment. Nuclear medicine:Most tumors (excluding Disturbances in sphincter function are associated with a myeloma) exhibit increased activity on nuclear poor prognosis for recovery. medicine scans. Primary CNS spinal cord neoplasms are usuallynot metastaticand generally have a more favorable prognosis for long-term survival than de metastases. Patients withleptomeningeal metastases have a poor prognosis. B3M3 Case 1 8of 8
