Disorders of the Musculoskeletal,

Where would you most likely find a Rhabdomyosarcoma?

1) 75% of Rhabdomyosarcoma occur in head, neck, and GU tract 2) Can also occur in trunk and extremities

What risk factors are associated with osteoporosis?

1) Cigarettes- hypoxemia and inflammation that ensue 2) Vitamin C absorption deficiencies (e.g. cystic fibrosis patients) 3) Decrease in testosteron/estrogen 4) Decrease in Vitamin D and Magnesium levels 5) Decreased activity level

What % of muscle strength is lost EVERY DAY that muscle is inactive?

3%

What is normal bone density?

833 mg/cm2

What is the difference b/w a complete and and incomplete fracture?

A complete fracture occurs when the bone breaks all the way through... While an incomplete fracture occurs when there is damage but bone is still enact (in one piece)

What is a fatigue stress fracture?

A fatigue stress fracture occurs when theres abnormal stress or torque applied to a bone with the normal ability to deform and recover (e.g. are dancers, joggers, military)

What characterizes a Greenstick fracture?

A greenstick fracture is one that occurs on only ONE cortex of the bone.

What is a linear fracture?

A linear fracture occurs along the long axis of the bone.

What is a Myelogenic Tumor?

A myelogenic tumor is one that originates from various marrow cells.

What is a pathologic fracture?

A pathologic fracture is one that occurs at the site of a pre-existing abnormality (e.g. a disease process), where a force to the site would not cause a fracture under normal conditions. e.g. a fracture that occurs on a bone where theres a presence of osteoporosis, an infection, or a metabolic bone disorders .

What is a strain?

A sTrain (T for tendon) is injury or a tear to a tendon.

Which type of fracture is usually associated with child abuse and why?

A spiral fracture is usually indicative of child abuse. Could be a sign of bone twisting.

What is a sprain?

A sprain is injury or a tear of a LIGAMENT

What is a stress fracture?

A stress fracture occurs when there is normal or abnormal bone which endures a fracture due repeated stress (e.g. athletes), where the stress is less than what would normally cause a fracture. (***can think of as progressive or chronic)

What single synovial fluid characteristic helps to diagnose an INFLAMED joint disease?

A synovial fluid WBC count > 2000 ***note, on test don't use serum, not same as synovial fluid

What is the difference between a ligament and tendon?

A tendon joins a muscle directly to the bone. -e.g is the achilles tendon While a ligament joins a bone to a joint -e.g. the illiofemoral ligament

What is a transchondral fracture?

A transchondral fracture is one where fragmentation and separation occur at the articular cartilage that covers the end of a bone at the joint.

What is a transverse fracture?

A transverse fracture is when a fracture runs straight across the bone.

What other pathophysiological process besides terminal vessel thrombus can cause necrosis of infected bone?

Abscess formation under periosteum--> lifts periosteum off the bone--> disrupts the blood vessels that enter the bone in the periosteum--> depriving bone blood supply

Osteoarthritis, like osteoporosis and cancer, is a disease of...? What is Osteoarthritis's primary cause?

Age...Primary cause for Osteoarthritis is Idiopathic (unknown)

What is the most common cause of Toxic Myopathy?

Alcohol Abuse!!!

What is the most common malignant primary bone tumor and for what percent of bone tumors does it account for?

An Osteosarcoma is the most common malignant primary bone tumor and it accounts for 38% of all bone tumors.

What is an insufficient stress fracture?

An insufficient stress fracture occurs when stress is applied to a bone w/ the inability to deform and recover (i.e. normal weight bearing)

What is an oblique fracture?

An oblique fracture is when the fracture occurs at a slant on the shaft.

What is the difference b/w an open and closed fraction?

An open fracture (compound) is when a complete or incomplete fracture breaks the skin, and bone is exposed A closed (aka simple) fracture occurs when the incomplete or complete fracture occurs without breakage of th skin

What is an osteoclast?

An osteoclast is a differentiated bone cell that functions to reabsorb bone.

What is unique about bone and the liver in their repair process?

As repair occurs, FUNCTIONAL tissue is layed down as oppose to scar tissue in the heart, skin, and brain.

What is Avascular Necrosis and where is it most commonly seen?

Avascular necrosis is hallmark of a Femoral Dislocation. What happens is the blood supply is obstructed so much (e.g. elbow process of ischemic paralysis) than bone tissue death occurs.

In a biopsy, what pathophysiological finding would you find in someone w/ Toxic Myopathy?

Individual Muscle Cell Fiber Necrosis

What is the pathophysiology of Osteomyelitis?

Infection-->triggers and inflammatory response--> causes terminal vessels to thrombose, and exudate seals canalculi-->impairs blood flow--> necrosis of infected bone

If you were to put a needle in a Rheumatoid Arthritic joint, what would expect to find?

Inflammatory exudate w/ increased WBC presence

What is Gouty Arthritis?

Is when the uric crystals due to hyperuricemia, are deposited in the synovial membrane.

What is so dangerous about a fibrosarcoma?

It can metastasize and lodge in the blood

What does the Pannus cause?

It causes scar formation which eventually becomes fixed, making the joint immobilized.

Essentially, what is Ankylosing Spondylitis?

It is a chronic inflammatory disease of the spine and/or sacroiliac joints that causes stiffening/pain and fusion (ankylosing) of the joints.

What is Hyaluronan and what is its function?

It is a glycoaminoglycan that is produced via type B synovial cells Hyaluronan's purpose is to provide the synovial fluid with viscosity

What is a Contracture?

It is a shortening of the muscle finer w/o an action potential

What is Osteomyelitis and what is the most common cause?

It is an infection of the bone, mostly due to gram (+) Staphylococcus Aureus.

What is a Collagenic Tumor?

It is bone tumor that produces fibrous connective tissue.

What characterizes an Osteosarcoma?

It is comprised of masses of Osteoid, which would appear as "streamers" or non calcified bone matrix and callus

What is ischemic paralysis?

It is hallmark symptom of a dislocation where circulation has been cut off so much that motor function is lost or at least impaired.

What is a Chondrogenic Tumor?

It is one that produces cartilage (chondroid) or a primitive cartilage-like substance.

What is Gout?

Its a metabolic disorder that alters the bodies control of the production or excretion of uric acid.

What characterizes a dislocation?

Its a temporary displacement between two bones and there is loss of contact between the articular cartilage.

What are the early symptoms of Ankylosing Spondylitis?

Lower back pain, stiffness, and limited Range of Motion

After Osteoid is layed down what occurs?

MINERALIZATION of osteoid occurs w/in 3-4 weeks.

What is a Rhabdomyosarcoma?

Malignant muscle tumor of striated muscle

What other categories do we use to classify Joint Disease?

Mechanical vs. Inflammatory

What is the most common collagenic tumor and for what percent of bone tumors does it account for?

Most common collagenic tumor is Fibroarcoma and it accounts for 4% of all one tumors.

Where are the most common locations for a Rhabdomyosarcoma?

Muscles of head, neck, GI tract (these 3 account for 75% of all cases) Can also occur in the trunk and extremities

Chondrogenic Tumors account for what percent of bone tumors?

Chondrogenic tumors, specifically Chondrosarcomas account for 20% of all bone tumors, 2nd behind Osteosarcomas.

What are the two forms of Rhabdomyolosis, and which is the most severe, why?

Compartment Syndrome and Crush Syndrome Crush Syndrome can lead to Renal Damage and Circulatory (dysrhythmias)/Systemic Problems (Shock).

What are the 2 main classifications of fractures?

Complete fractures and Incomplete fractures

How much time of inactivity must pass in order for disuse atrophy to be apparent?

DAYS!!

What is the first step in Bone Remodeling?

Osteocyte apoptosis near the fracture site signals OSTEOCLAST RECRUITMENT via pre-osteoclasts circulating in the blood

What are the two types of stress fractures?

Fatigue and Insufficiency fractures

What are the different types of Bone Tumors?

Osteogenic, Chondrogenic, Collagenic, & Myelogenic

Essentially, what is Osteomalacia?

Osteomalacia is a metabolic disorder where the bone is unable to mineralize and calcify during the later stages of bone formation b/c of inadequate concentrations of calcium and phosphate.

What differentiates Osetomalacia from Osteoporosis?

Osteomelacia is a disorder that strictly affects bone formation as opposed to Osteoporosis which affects resorption as well as bone formation.

What are the symptoms associated w/ Osteoporosis?

Osteoporosis is Asymptomatic...reason why one should undergo Bone Mass Density Test before a fracture or injury occurs.

What is used to determine/evaluate Osteoporosis, and what signifies Osteoporosis?

Osteoporosis is determined by measuring BONE MASS DENSITY TEST. A bone mass density < 648 mg/cm2 signifies reduced bone density as well as imbalance of resorption and bone formation

Essentially, what is Osteoporosis?

Osteoporosis is disruption of the bone remodeling process; bone resorption and formation.

What are some of the Manifestations of Osteoarthritis?

Pain, Tenderness, Stiffness, Enlargement of joints, Limited Range of Motion, and Deformity

In what type of patients will you see a contracture?

Patients w 1) a cerbrovascular injury or 2) PRONGED IMMOBILIZATION OF JOINTS (Osteoarthritis, Rheumatoid Arthritis, or Ankylosing Spondylitis)

What other abnormalities are dislocations and subluxations associated with?

Fractures, Rheumatoid Arthritis, Muscle imbalance, and other joint instabilities.

What occurs after Osteoclast Recruitment in Bone Remodeling ?

RESORPTION of injured bone occurs due to stimulation of pre-osteoclast maturity via pre-osteoblast generation.

What other condition is associated with Rheumatoid Arthritis?

Raynaud's Phenomenon

What is Polymyositis?

Generalized muscle inflammation (multiple muscle=polymyo)

What is the primary myelogenic tumor and for what % of bone tumors does it account for?

Giant Cell Tumor and it accounts for 4-5% of all bone tumors.

Where does Giant Cell Tumor get its name and what characterizes its pathology?

Giant Cell Tumor is made of giant osteoclast-like cells and functions in extensive resorption like regular osteoclasts. Giant Tumor Cells undergo a slow but relentless growth

Where would you most likely find Giant Tumor Cells?

Humerus, Radius, Femur, and Tibia

What physical presentation would you find in someone with Ankylosing Spondylitis?

Hunched Shoulders w/ NO LUMBAR CURVATURE

What unique characteristic regarding spread of infection, differentiates Exogenous from Endogenous Osteomyelitis?

In exogenous osteomyelitis the infection spreads from soft tissues to bone Where as in endogenous (hematogenous) osteomyelitis, the spread occurs from bone to soft tissue

With osteoporosis, what appears a fine and what is lacking?

In osteoporosis, bone histology appears normal but it is structural integrity that is lacking.

Where are Osteosarcomas located?

In the Metaphyses of long bones, with 50% those in areas around the knee.

What is Rhabdomyolysis and what are its most common causes?

Rhabdomyolysis aka Myoglobinuria is a LIFE-THREATNING complications classified by the presence of excess myoglobin in urine; which is released via injured muscle cells. Rhabdomyoliysis is usually due to multiple musculoskeletal injuries seen in car crashes or in drug/ETOH overdoses.

What forms of Arthritis are commonly referred to the "Classic" Inflammatory Joint Diseases?

Rheumatoid Arthritis (RA), Anklylosing Spondylitis (AS), and Gout

What is Rheumatoid Arthritis?

Rheumatoid Arthritis is an autoimmune disease that damages the connective tissue of multiple joints at the synovial membranes.

Gout çan be primary/idiopathic or ??

Secondary to increased purine diet.

To avoid infarction and Crush Syndrome, what is done to relieve Compartment Syndrome in Rhabdomyolisis?

Skin is opened, to relieve compartment pressure caused by edema and muscle hypertrophy.

What characterizes subluxation?

Subluxation is characterized by PARTIAL loss of contact between the articular cartilages of two bones.

Destruction of these TWO indicates Inflammatory Joint Disease?

Synovial Membrane Destruction or Articular Cartilage Destruction

What are the common characteristics of Classic Arthritis (e.g. RA, AS, Gout)

Systemic signs of inflammation such as: 1) FEVER 2) INCREASED WBC 3) Malaise 4) Anorexia (decreased appetite) 5) hyperfibrinogenemia

Explain the pathophysiology behind Acute Arthritis?

The inflammation that ensues-->releases neutrophils-->neutrophils release reactive oxygen species-->cause damage-->hyaluronan depolymerization-->proteolytic enzymes are released, increasing inflammation and damage.

What occurs after Osteoblast Recruitment in Bone Remodeling?

The mature osteoblasts fill the cavity left by osteoclast resorption, laying down OSTEOID FORMATION (still soft, flexible bone matrix).

After Mineralization of osteoid, what occurs in Bone Remodeling?

The mineralized osteoid continues to accumulate minerals and increase density, MATURING new bone tissue.

What happens after necrosis of surrounding bone tissue in the pathophysiology of a complete fracture?

The necrosis simulates an INTENSE inflammatory response.

How does the osteoid mineralize and calcify, what elements are involved?

The osteoid is mineralizes and calcifies via Ca+ and Phosphate which crystallize osteoid minerals.

What is Dermatomyositis

This is Polymyositis with skin lesion (derm)

What characterizes an avulsion?

This is complete separation of a ligament or a tendon from its bone attachment site.

After the severe inflammatory response, what occurs in the pathophysiological process of a complete fracture ?

Vascular tissue invades the fracture from surrounding soft tissue and marrow to supply blood and new osteocytes (bone cells) for repair.

What characterizes the initial inflammatory response following necrosis in the pathophysiology of a complete fracture?

Vasodilation, exudation of plasma, & infiltration of inflammatory leukocytes and mast cells .

What causes myositis?

Viral, parasite, and bacteria

Explain the pathological process behind Osteomalacia?

Vitamin D deficiency occurs--> decreases absorption of Ca+--> decreases the plasma Ca+--> stimulates synthesis/secretion of PTH--> increases serum Ca+ but at the price of increasing renal excretion of phosphate

If uric acid concentrations levels increase to high enough point, what forms? Where do these formations occur?

With hyperuricemia, there can be crystal formation which will deposit in the connective tissue of the body.

What indicates a + RF(RA) Test?

You would find recently transformed antibodies (IgM and IgG), referred to at this point as Rheumatoid Factors, starting to bind to targets in blood and synovial membranes.

What signifies osteopenic bone?

a bone density of 648 mg/cm2-833 mg/cm2

What is the first step in the pathophysiology of a complete fracture?

bleeding which is caused by disruption of Periostium and blood vessels in the cortex, marrow, and surrounding tissues are disrupted.

Dislocation of elbows is associated with what in pediatrics?

fractures caused by pulling kids by their wrists...to prevent, pull up from under shoulders

What ensues after the initial bleeding in the pathophysiology of complete fracture?

hematoma (blood clot) forms within the medullary cavity, between the broken ends of a bone, beneath the periosteum.

What usually causes a greenstick fracture?

minor direct or indirect energy.

What are some of the clinical manifestations of Osteomalacia?

pain, soft bones susceptible to fractures, spinal collapse, bone malformations (e.g. sparse clavicle on x-ray, or "bowed" legs)

After the hematoma, what is the next step in the pathophysiology of a complete fracture?

the bone tissue, adjacent to the fracture, begins to die (necrosis).

What is significant about the fused joints?

they cause stiffening and immobilization of spine/sacroiliac joints--> not allowing patient to straighten back

What characterizes Osteoarthritis?

1) Degenerative loss of Articular Cartilage 2) Sclerosis (hardening) of bone underneath cartilage 3) Formation of Osteophytes (bone spurs)- smooth bony growths over

How does increase in Purine occur?

1) Increase in Purine Synthesis 2) Decrease in Purine Breakdown 3) Or POOR URIC ACID SECRETION

What main characteristics are associated with Rheumatoid Arthritis?

1) Inflammation w/ hemorrhage 2) Pannus formation

Describe the pathophysiological process associated with a dislocated elbow ?

1) Initial bleeding caused by trauma to periosteum can cause muscles to compress on arteries 2) If pressure by muscle isn't relieved, then circulation to and from the forearm/hand is obstructed 3) Resulting in Ischemic Paralysis

What lethal characteristic does a Rhabdomyosarcoma have?

1) Is highly malignant 2) has rapid mastastasis

What are the characteristics of Synovial Fluid?

1) It is TRANSUDATE of the plasma, meaning filtered to blood vessels (like pleural fluid) 2) Usually has a WBC count < 200 cells/mm3 3) Is made of Hyaluronan

What characterizes a Chondrosarcoma Tumor?

1) It will usually infiltrate the trabeculae (spongy bone) & often present in the metaphysis/diaphysis of long bones 2) Tumors contain hyalin cartilage that expand and enlarge bone 3) Cause erosion of the cortex and expands into neighboring soft tissue.

Complete and incomplete fractures can be characterized by other classifications, what are they?

1) Open vs. Closed 2) Linear vs. Oblique vs. Transverse 3) Pathologic vs. stress vs. transchondral

What is a Pannus and how does it develop?

1) Pannus is fibrin that accumulates on the damaged synovial membrane that eventually granulates. 2) A Pannus forms via the inflammation/hemorrhage which causes hyper-coagulation, and fibrin deposition on the matrix of the synovial membrane/ fluid.

Clinically, whats commonly associated with Osteomyelitis?

1) Sicle Cell Anemia (in which this case Salmonella is the main pathogen) 2) Hypoxemia (especially localized tissue hypoxia) 3) Immunocompromised patients (e.g. infants, children, elderly)- where in this case Myobaceteria and Fungus are main pathogens

What two physical characteristics are associated w/ Rheumatoid Arthritis?

1) Ulnar Drift (hand is turned inward) -arthristis has spread to larger joints e.g. ulnar 2) Subcutaneous Nodules (on knuckles)

How would you evaluate Rheumatoid Arthritis and make a diagnosis?

1) You would run a Rheumatoid Factor Test 2) You would also want to see Osteoarthritis Symptoms (Fever, inflammation, & increase WBC) but in more than one joint!

What is the distinguishing characteristic between an inflammatory joint disease (Acute Arthritis) and a non-inflammatory joint disease and what are the other distinguishing characteristics?

1) normal synovial fluis analysis would characterize a non-inflammatory joint disease 2) A non-inflammatory disease lacks the presence of synovial membrane inflammation 3) No systemic abnormalities is a marker of a non-inflammatory joint disease (e.g. no fever, no increase WBC)

What causes disuse atrophy?

Bed rest, casting, nerve damage, or trauma

Bone is continuously doing what and what facilitates this ongoing process?

Bone is continuously REMODELING. Remodeling is facilitated by osteoclasts and osteoblasts.

What characterizes an Osteogenic Tumor?

Bone or osteoid tissue that forms w/ a sarcomatous tissue.

After vascular invasion of fracture site, what occurs in the pathophysiological process of a complete fracture?

Bone-FORMING cells are activated.

There are two types of joint deformities/enlargements associated with Osteoarthritis, what are they?

Bouchard Nodes and Heberden Nodes.

What differentiates Bouchard and Heberden Nodes?

Bouchard Nodes are enlargement of the Medial Joints while Heberden Nodes are enlargement of the Distal Joints

What does the disruption of uric acid production/excretion by Gout cause?

Causes high concentrations of uric acid in the blood aka hyperuricemia, as well as in other bodily fluids.

What else is Osteoarthritis referred to?

Degenerative JOINT Disease

What is Disuse Atrophy?

Disuse Atrophy is a pathologic decrease in the normal size of muscle cells due to prolonged inactivity

What characterizes Compartment Syndrome in Rhabdomyolysis?

Edema ensues after trauma--> increase in "compartment pressure" --> causes muscle ischemia--> and can lead to infarction (Crush Syndrome)

What is Gouts's increase in uric acid concentration related to?

Excess Purine (guamine and adenine).

What is the most common type of Osteomyelitis?

Exogenous Osteomyelitis

What are the two types of Osteomyelitis, and differentiate the two?

Exogenous and Endogeonus (Hematogenous). Exogenous Osteomyelitis is when an infection enters from the outside and into the body Endogenous (Hematogenous) Osteomyelitis is when an pathogens are carried from sites of infection to other parts of the body.

After Reabsorption of damaged bone, what occurs in Bone Remodeling?

OSTEOBLAST RECRUITMENT occurs via stimulation of pre-osteoblast maturity and move towards reabsorbed cavity.

What are the mechanisms that allow Exogenous Osteomyelitis; in other words, through what means does a pathogen make its way in?

Open fractures, penetrating wounds, or invasive surgical procedures

What is an osteoblast?

Osteoblasts are differentiated bone cells from marrow stromal cells that facilitate the layers of osteoid (pre-mineralized bone)