Ch16 Main Ideas
Clinical manifestations of musculoskeletal tumors
Pain, fractures, swelling , mass , and metastasis
A tumor that could as or
Bone Island - small, oval, sclerotic (hardened) lesions of bone; common, asymptomatic; do not develop into malignant lesions
Osteoblastoma - larger and tend to expand; spine, sacrum, and flat bones
Benign bone tumor
Composed of endothelial cells and tight junctions, allowing only certain substances to pass.
Drug entry is determined by its lipid solubility.
Ependymal cells line the ventricles and spinal canal, forming the basis of the CSF barrier.
Blood-Brain Barrier
Decreased muscle tone, which can be ipsilateral or bilateral and primarily affects proximal muscle groups
Hypotonicity
Ability to hold information in short-term storage while permitting other cognitive operations to occur.
Working Memory
4 types of genetic disorders that can lead to soft tissue tumors
Translocations - parts of chromosomes switch places
Gene amplifications - genes are copied too many times
Mutations - changes or errors in genes
Complex genetic imbalances - uneven abnormal distribution of genetic material
Balance of bone formation and resorption is disrupted by malignant cells and the process of remodeling becomes unbalanced
Cancellous bone has higher metabolic activity - why many disorders are first noted here
Bone tumors
Neuronal cell death occurs through two main processes:
Necrosis: Cell swelling, membrane rupture, and release of cytotoxic compounds cause destruction of neighboring cells. (due to disease or injury)
Apoptosis: Programmed cell death without causing inflammation; the cell is removed by macrophages. (normal cell death)
Lack of coordinated movements, often due to cerebellar dysfunction—no direct synapse between cerebellum and spinal cord.
Ataxia
Inability to recognize an object.
Agnosia
Describe different primary soft tissue tumors
Benign soft tissue tumors
Lipoma - mature fat cells, superficially located in subcutaneous tissue; asymptomatic
Ganglia - arise from joint capsule or tendon sheath; usually on the dorsal aspect of the wrist
Popliteal cyst (bakers cyst) - subtype of ganglia; behind the knee
Nerve sheath tumor
Neurofibromas
Schwannomas - covering of peripheral and cranial nerves
Malignant soft tissue tumors
Soft tissue sarcomas - arise predominantly from embryonic mesoderm and manifest as an asymptomatic mass; can occur anywhere in the body but most are in extremities
More than 50 histologic types of soft tissue sarcomas
Metastatic tumors
Skeletal involvement is the 3rd most common site of metastatic spread
Ex: breast cancer is commonly spread to spine - breast cancer usually spreads through blood and spine has a rich blood supply
2 examples of malignant bone tumors
Osteosarcoma
Extremely malignant tumor
Destructive lesions and abundant sclerosis - from the tumor and reactive bone formation
Seems to appear in bones in active growth
Resistant to radiation - complete surgical removal is essential
Use of expandable prosthesis for immature skeletons (children)
Ewing’s sarcoma
Arises in bone or soft tissue
Primarily in young people (<20 yrs old)
Soft tumor with hemorrhagic necrosis - rapid tumor growth that can outpace its blood supply
Better prognosis if in distal sites (hands and feet as opposed to sacrum or pelvis)
Clinical Manifestations of CNS Disorders
Sensory Disturbances: Symptoms occur on the contralateral side of the lesion when the disorder is above the level of the brainstem.
Movement Disorders: Movement control is initiated in the cerebral cortex (parietal and premotor areas) and involves coordination, balance, and motor control.
Frontal Lobe: Lack of judgment or understanding consequences, withdrawal and irritability, apathy, and lack of inhibition.
Right Hemisphere Syndrome: Inability to orient the body within external space or generate an appropriate motor response, including hemineglect (failure to respond to sensory stimuli on the left side of the body).
Memory Problems
Generalized weakness.
Asthenia
Disorders of recent memory, commonly seen with TBI.
Amnesia
Hematopoietic neoplasm involving bone marrow
Common where bone marrow is found in high concentrations (femur, humerus, pelvis, vertebrae)
Presents with deep bone pain
Multiple Myeloma
Overshooting or undershooting movements toward a target,
Dysmetria
Retention of facts and events from prior experiences.
Declarative Memory
Inability to perform rapidly alternating movements (no rhythm or consistency; inability to stop ongoing movement).
Dysdiadochokinesia
Learning of skills and habits.
Procedural Memory
Slow, monotone speech.
Scanning Speech
Failure to form new memories.
Anterograde Amnesia
Non-voluntary rhythmic oscillation of the eye; inability to hold gaze on an object.
Gaze-Evoked Nystagmus
Loss of the ability to recall past events.
Retrograde Amnesia
Observed when eyes move from one target to another.
Ocular Dysmetria
Fabrication of information in response to questioning.
Confabulation
Due to cerebellar dysfunction, characterized by wide-based, uneven steps, loss of typical arm swing, feet lifted higher than necessary, and loss of adaptation to changes in terrain.
Gait Disturbances
What neurochemical changes happen to our brain as we age
Decrease in receptors.
Decrease in the synthesis of neurotransmitters.
Decrease in serotonin, affecting respiration, thermoregulation, sleep, and memory.
Articulation issues.
Dysarthria
Provides a snapshot of the CNS; can identify damage within tissue, blood flow issues, multiple sclerosis, neoplasms, and infections. Excellent for detecting acute intracranial hemorrhage.
Computed Tomography (CT)
Difficulty producing speech
Anarthria
Recognizable signal patterns; the study of choice for evaluating all lesions of the brain and spine. Cannot be performed on patients with intraorbital foreign bodies, pacemakers
Magnetic Resonance Imaging (MRI)
Deficit in speech production and language output (garbled and inappropriate words).
Expressive Aphasia
Detects abnormalities such as brain lesions, blood flow issues, or tumors.
Positron Emission Tomography (PET)
Inability to read (prevention of visual information from being processed for linguistic interpretation).
Alexia
Measures the brain’s electrical activity; useful for detecting ischemia or seizure activity. The depth of ischemia is associated with the severity of EEG changes.
Electroencephalography (EEG)
Abnormal or clumsy writing.
Agraphia: Abnormal or clumsy writing.
Potentials generated in the auditory nerve and recorded in different regions of the auditory pathways in the brainstem.
Brainstem Auditory Evoked Potentials
Disorder of skilled purposeful movement, which includes:
Ideomotor ______: Inability to carry out a motor act on verbal command.
Ideational ______: Failure to perform a sequential act, despite being able to perform each part individually.
Apraxia
Measures local blood flow velocity in the proximal portions of large intracranial arteries.
Transcranial Doppler Ultrasonography