Musculoskeletal System Flashcards
What are the purposes of the skeletal system?
-Gives body form
-Supports tissues (keeps things in place)
-Permits movement
-Protects organs like the brain, spinal cord, heart, and lungs
-Mineral storage
____ bone is a dense shell that defines the shape of the bone and makes up 85% of skeletal tissue; gives our bones strength and covers the inside of the bone
Compact
____ bones gives bone a lattice framework; contains red and yellow marrow
Spongey
____ is the covering of the bone; it has two layers, the inner layer anchors to the bone and the outer layer carries blood vessels to penetrate all layers of the bone
Periosteum
____ is the lining for soft bone
Endosteum
____ are the bone-building cells
Osteoblasts
____ maintain the bony matrix and facilitate nutrient extraction from the blood
Osteocytes
____ are involved in the resorption of bone and contain hydrolytic enzymes that are especially active after a bone break or with the release of parathyroid hormone
Osteoclasts
____ is the formation of pre-bone
Ossification
____ describes the process of depositing minerals into bone; minerals bind to collagen fibers in the bone to give tensile and compression strength
Calcification
The bone ____ is the extracellular elements of bone tissue
Matrix
_____ fibers are synthesized by osteoblasts
Collagen
Collagen fibers are formed as ____ ____, and three of them twist into a fibril; fibrils will form crossing patterns with holes where minerals will be deposited
Alpha chains
Collagen fibers provide tensile ___ and ____
Strength and support
____ is a mineral deposited into the bones for storage and strength
Calcium
____ exist in the bony matric and shuttle calcium around and form a network between fibrils to strengthen bone
Proteoglycans
____ binds to calcium and inhibits calcium-phosphorus precipitation; it recruits osteoclasts
Osteocalcin
Osteonectin binds to ____ in bone as well and promotes bone growth
Calcium
____ stimulates neurite and axon growth and stimulates the bony membrane
Laminin
Bone ____ transports elements like calcium and electrolytes into the bone
Albumin
Alpha _____ binds to calcium and activates osteoclasts
Glycoprotein
____ marrow is the site of hematopoiesis and is biologically active
Red
____ marrow is made up of fat tissue
Yellow
A bone ____ is a break in the continuity of the bone
Fracture
Who are at the highest risk for bone fractures?
-Young males
-Elderly (have thinner matrix)
-Individuals with bone or calcium disorders
A ____ (simple) fracture is non-communicating between skin and bone
Closed
An ____ (compound) fracture is communicating between the skin and bone (bone pokes through the skin)
Open
A ____ fracture causes multiple bone fragments (eggshell)
Comminuted
____ fractures are parallel to the long axis of the bone
Linear
____ fractures are horizontal fractures of the bone and are usually more serious than linear
Transverse
____ fractures are all the way through the bone
Complete
_____ fractures are not all the way through the bone, and are more common in flexible, growing bones of children
Incomplete
____ fractures occur when part of the bone that is attached to a ligament breaks off
Avulsion
____ fracture is when a bone breaks due to weakening from disease, commonly with weak force (occurs with tumors, osteoporosis, infection, and metabolic bone disorders)
Pathologic
____ fractures are incomplete microfractures due to low-impact stress
Stress
____ fractures are a break only in the cortex (outer layer) of bone and are more common in kids
Greenstick
Manifestations of bone fractures vary by site and type, but commonly include…
-Unnatural alignment
-Swelling
-Tenderness, muscle spasms
-Pain
-Impaired sensation (pinched nerve, severed nerve)
-Impaired function and crepitus (air pockets in the skin that sounds like bubble wrap)
What are the four phases of fracture healing?
-Hematoma formation if vessels have been damaged (hours)
-Inflammatory phase (1-2 days)
-Reparative phase (1 week to months)
-Remodeling phase (several weeks and beyond)
What happens during the first phase of fracture healing, hematoma formation?
-Fibrin and platelet entry
-Surrounding bone death
-Cytokine entry
-Inflammatory process is initiated
What happens during the second phase of fracture healing, the inflammatory phase?
-Cytokines, enzymes, and growth factors enter the site
-Vasodilation (leukocyte and mast cell entry)
-Osteoblast entry
-Procallus formation
-Cartilage and collagen formation
What happens during the third phase of fracture healing, the reparative phase?
-Osteoblasts form membranous bone, “callus”
-Phosphate content is increases
-Callus is replaced by bone
What happens in the fourth phase of fracture healing, the remodeling phase?
-Periosteum/endosteum remodeling to give shape and strength to the bone so it can function normally
-Weight-bearing and motility
Factors that affect healing of bone:
-Nature of the injury
-Immobilization and realignment (traction)
-Infection
-Hormones, growth factors, vitamin D, calcium
What are some complications of healing?
-Union
-Fat emboli syndrome
-Compartment syndrome
-Osteomyelitis
With a ____, there is a failure of the bone to grow together when it heals
Nonunion
With a _____ union, it takes longer than normal for the fracture to heal
Delayed
With a ____, the bones don’t join up correctly
Malunion
Fat emboli syndrome occurs when there is _____ to long bones
Trauma
Mechanism of fat emboli syndrome:
-Abnormal fat metabolism
-A piece of fat from the marrow moves out into the bloodstream and then there is fat traveling through the lungs which eventually causes an embolism
Fat emboli syndrome is most common in ____ or ____ fractures and there is increased risk if the injury is not properly immobilized
Femur or pelvis
When the fat is traveling to the lungs, ____ adhere to it and it causes acute respiratory distress syndrome
Platelets
Manifestations of fat emboli syndrome:
-Hypoxia on ABG
-Low hemoglobin
-Thrombocytopenia
-Fat in blood clots
Compartment syndrome causes abnormal increases in ____ within a confined anatomic space, resulting in impaired circulation, nerve injury, and loss of muscle
Pressure
Compartment syndrome usually occurs in someone in a ____ or constrictive dressing
Cast
Pathogenesis of compartment syndrome:
-Increased pressure
-Lack of blood flow
-Nerve damage
-Muscle death
Compartment syndrome risk is increased with…
-Casting
-Infection
-Burns
-Repeat stress
Mechanism of compartment syndrome:
-Weight of limb cases cell damage
-Cell damage causes edema
-Edema increases pressure
-Tamponade effect
-Muscle/nerve cell infarction and death
-Myoglobin release
-Further edema
Manifestations of compartment syndrome:
-Pain
-Paresthesias
-Pressure > 30mmHg (pulselessness)
-Release of myoglobin
-Elevated creatinine kinase
Compartment syndrome is treated with ____
Fasciotomy
_____ is an infection of the bone
Osteomyelitis
What are two possible etiologies of osteomyelitis?
-Direct contamination (exogenous): someone has an open fracture and it gets infected at the time of the injury (common with gut shot wounds and bites)
-Hematogenous (endogenous): blood to bone; infectious agent moves from the blood to the bone, seen when someone has an infection anywhere in the body that moves to the bone
Manifestations of osteomyelitis:
-Varies with age, site, organism, and source
-Inflammation
-Fever
-Malaise
-Anorexia
-Weight loss
-Septicemia
-Swelling, erythema, tenderness
-Pain
-WBC elevation or not
Complications of osteomyelitis:
-Arthritis
-Pathological fractures
-Chronic osteomyelitis
-Bone cancer
____ ____ increases serum calcium and is released when there is low blood calcium and stimulates osteoclasts to break down and increases kidney resorption of calcium
Parathyroid hormone
____ decreases serum calcium, decreases osteoclast activity, decreases renal absorption of calcium (more excreted in urine), and overall has the opposite effect of PH
Calcitonin
Vitamin ____ needs to be metabolized to be active; it is heavily regulated by parathyroid hormone and helps to maintain calcium
D
____ is a disease that causes a higher rate of bone resorption than bone formation, which leads to decreased density of bone tissue
Osteoporosis
We are able to build bone through our ____, and things like exercise and healthy diet with calcium and vitamin D can help
30s
We have ___% bone loss every year after age 40, and 1% per year in menopausal women
0.5
Osteoporosis is uncommon in ____ ____
African Americans
_____ are a drug that break down bones by inhibiting osteoblasts
Corticosteriods
Osteoporosis is ____ in men
Secondary
What are some causes of osteoporosis?
-Estrogen (decreased levels after menopause, overstimulated osteoclasts)
-Dietary (decreased dietary intake of calcium, magnesium, vitamin D; phosphate binds calcium and makes it inactive and promotes osteoclasts)
-Exercise can help keep and maintain bone mass
-Smoking cessation may help (smoking decreases estrogen)
-Hormones
-Drugs
What are some pathological changes seen with osteoporosis?
-Loss of organic matrix and the mineral content of bone
-Loss of spongey (cancellous) bone
-Decreased thickness of bone cortex
-Slower cycle of bone remodeling (we normally replace bone every 40 days, but it would take 2 years with osteoporosis)
-Menopause: decreased estrogen
Manifestations of osteoporosis:
-Pain
-Fractures
-Kyphosis (slumping of spine)
-Fatal complications include fat or pulmonary emboli, hemorrhage, shock
____ provide stability where bones meet
Joints
_____ are immovable joints like in the skull or between the tibia and fibula
Aynarthroses
_____ are slightly moveable joints like where the rib meets the sternum or the pubic bones
Amphiarthrosis
____ are a fibrous joint capsules supported by cartilage like the elbow and shoulder
Diarthroses
The ____ cartilage is the smooth, white tissue that covers the ends of bones where they come together to form joints
Articular
The ____ ____ is the inner lining of the joint
Synovial membrane
The ___ ___ acts as lubricant for joints
Synovial fluid
____ ____ is an autoimmune, systemic inflammatory disease which causes inflammation of connective tissue, primarily in the joints
Rheumatoid arthritis
Rheumatoid arthritis affects 1-2% of the population, and is much more common in what gender (3:1)?
Women
Peak incidence age is between ___-___ for rheumatoid arthritis (peak onset is between age 30-50)
40-60
What are three possible causes of rheumatoid arthritis?
-Genetics
-Viral infection earlier in life (EBV) or possibly even bacterial infection
-Hormones (estrogen-androgen imbalance
___ ___ is an auto-antibody that attacks the host connective tissue
Rheumatoid factor
Rheumatoid factor gets into the joints and activates the ____ cascade to cause massive inflammation in the joint
Compliment
The massive inflammation in the joint causes ____ enzymes to develop in the joint which destroys the cartilage
Lysosomal
Once the cartilage is destroyed, there is ____ formation which limits mobility and eventually leads to immobility of the joint
Pannus
Manifestations of rheumatoid arthritis are variable, seasonal, and systemic, but some systemical manifestations may include…
-Inflammation
-Weight loss, anorexia, fatigue
-Aching, stiffness
-Raynaud’s syndrome
-Respiratory dysfunction
-Hearing difficulties
-Kidney problems
What joints are usually affected by rheumatoid arthritis?
-Fingers
-Hands
-Wrists
-Feet
What symptoms does rheumatoid arthritis cause in the joints?
-Pain, stiffness (especially in the morning)
-Swelling
-Mobility
-Cyst formation/rupture
One example of a degenerative joint disease is ____
Osteoarthritis
Risk of osteoarthritis increases with ____ and is more likely to affect those over 40 years old
Age
Primary osteoarthritis is ____ and affects all joints in the body
Idiopathic
Secondary osteoarthritis is more ____, and has known risk factors
Common
Osteoarthritis is more common in what gender?
Men
The cause of osteoarthritis is joint instability which can be caused by…
-Genetics
-Repetitive impact loading (sports=most common cause)
-Congenital
-Trauma
-Other disorders
-Certain drugs
Mechanism of osteoarthritis:
-Progressive loss of cartilage
-Thickening and hardening of bone ends
-Bone spur formation
-Cyst formation
Manifestations of osteoarthritis:
-Severe joint pain (aggravated by weight bearing)
-Stiffness
-Limitation of motion
-Joint instability
-Deformity
-Synovitis
____ is caused by an increased level of uric acid, which leads to an inflammatory response
Gout
The cause of primary gout is unknown, but secondary gout can be caused by…
Hyperuricemia-producing drugs or disorders
Males and females are both affected by gout, but the ____ of onset differs between genders since estrogen may be protective
Age
Gout can be caused by ____ or ____ factors
Genetics or environmental
Mechanism of gout:
-Purine metabolizes to uric acid
-Uric acid builds up, forming monosodium urate crystals
-Crystals deposit in joints, stimulating inflammation
-Neutrophil involvement
-Phagocytosis of crystals, phagocytes burst
Manifestations of gout:
-Increased uric acid (uricemia)
-Deposition of monosodium urate, neutrophils, and phagocytes (recurrent attacks of pain)
-Joint pain
-Renal disease (kidney stones)
-Tophi development (uric acid in the skin)
What are the three stages of gout?
-Asymptomatic
-Acute gouty arthritis: one attack of gout, maybe a second one much later
-Chronic tophaceous arthritis: progressive inability to excrete uric acid (deposit in joints and soft tissue)
The ____ is the connective tissue that gives form to the muscle
Fascia
The epimysium connects ____ to ____ (tendons)
Muscle, bone
The ____ is the middle layer of the muscle tissue; it creates smaller bundles of fibers
Perimysium
The _____ surrounds individual fascicles
Endomysium
____ are individual muscle fibers
Fascicles
The motor unit is the individual ___ ___ cell (lower motor neuron) and the muscle it innervates
Anterior horn
There are many ___ ___ that form a neuron
Motor units
Muscle fibers are innervated by ____ ____ neurons
Lower motor
Muscles contract as a _____ and there are many motor units in a single muscle
Whole
_____ units/receptors of the muscle cell bring sensory information into the muscle to get the right amount of contraction for the desired function
Sensory
____ are mechanoreceptors that sense stretch, they lie within the muscle fibers
Spindles
____ ____ organs are nerve cells that terminate on the tendon (gives us dynamic information about the stretch)
Golgi tendon
____ run the length of the muscle fiber and are the basic contractile unit of the muscle
Sarcomeres
Muscle function is an “___ __ ___” mechanism
All or nothing
Steps of muscle function:
-Activation: depolarization
-Coupling: calcium release
-Contraction: calcium binds to troponin and causes tropomyosin to move to allow for actin/myosin to contract
-Relaxation: calcium absorption
-Smoothing
____ contraction does not change the length of the muscle (no limb or joint movement occurs)
Isometric
____ contraction does change the length of the muscle (produces limb movement)
Isotonic
Symptoms of alterations in muscular function:
-Pain, tenderness
-Weakness
-Muscle wasting
-Fatigue and/or exercise intolerance
_____ is muscle cell loss
Rhabdomyolysis
Rhabdomyolysis can be caused by…
-Crush syndrome
-Compartment syndrome
-Immobilitty
-Viruses
-Drugs
-Tetanus
-Heat stroke
-Electrolyte disturbances
Pathophysiology of rhabdomyolysis:
-Weight of extremity generates pressure
-Ischemia
-Edema increases pressure in the compartment
-Eventual tamponade causes infarction, nerve damage, and cell death
-Muscle tissue death releases myoglobin
-Myoglobin damages kidneys
Manifestations of rhabdomyolysis:
-Regional effects (compartment syndrome)
-Renal syndrome (myoglobin in the urine)
-Systemic effects (high creatinine)
____ disorders affect the thyroid, which regulates muscle protein synthesis and electrolyte balance
Endocrine
____ ____ is a myophosphorylase deficiency (lack of muscle phosphorylase)
McArdle disease
Myophosphorylase is an enzyme that assists in ____ breakdown in tissue, so McArdle disease can cause energy failure and symptoms like fatigue and muscle intolerance
Glycogen
____ ____ deficiency causes abnormal glycogen metabolism and an accumulation of glycogen
Acid mutase
____ disease is an infant version of acid mutase deficiency
Pompei
____ deficiencies also lead to energy failure since our muscles need fat
Lipid
What are two examples of inflammatory muscle disorders?
-Myositis
-Polymyosititis
Myositis is a viral, bacteria, or parasitic infection of the ____; can be caused by Trichinosis
Myositis
____ is an autoinflammatory disorder that leads to the accumulation of B, Th, and Tc cells in muscle cells
Polymyositis
Impact of age on bones:
-Become brittle
-Impact is greater in women than men
-Decreased height
Impact of age on joints:
-Stiffness due to cartilage changes
-Decreased range of motion
Impact of age on muscle:
-Sarcopenia (age-related muscle loss)
-Decreased muscle strength
-Reduced oxygen intake, metabolic rate, and lean body mass
