Skeletal System Flashcards
What are the 2 classifications of skeletal fractures?
Complete - bone is broken entirely
incomplete - bone is damaged but still in one piece (common in children)
What are the types of complete fractures?
Comminuted - two or more fragments
Spiral - encircles bone
Transverse - straight across
Oblique - at an angle
Linear - lengthwise
what are the types of incomplete fractures?
Greenstick - one side is broken
Torus - outer portion of bone buckles but doesn’t break
Bowing - Bone pairs (tibia/fibula, radius/ulna) one bone breaks, the other one bends (difficult to treat)
Define open vs closed fracture
Open (compound) skin is broken and bone showing
Closed (simple) Skin in=s intact
What are the causes of bone fractures?
Sudden injury - fall, blow, or massive muscle contraction
Pathologic - prior bone-weakening disease (eg. tumour, infection, osteoporosis)
Stress - repeated stress (sports)
How to bone fractures heal?
similar to soft tissue healing
involves formation of a callus, with bone remodeling
No scar tissue is made during healing
What are the steps in healing?
- Clot forms in medullary cavity (hollow part of bone)
- Adjacent bone tissue dies (necrosis)
- Necrosis starts inflammation
- Phagocytic cells remove dead tissue, fibrocartilaginous callus makes a bridge called the procallus between bone ends
- Osteoblasts calcifies bone matrix, making a bony callus
- callus is remodeled by osteoblasts/clasts
Describe dislocation and the joints most affected.
displacement of one or more bones in a joint where surfaces lose all contact
Shoulder, elbow, wrist, knee, finger, hip
Define subluxation
same as dislocation but there is still some level of contact between surfaces
What are the 3 alterations in posture?
Kyphosis, Lordosis, and Scoliosis
Define Kyphosis and its cause
Increased curvature of upper spine
caused by diseases causing loss in bone density in vertebrae or fusion of joints between vertebrae
Define Lordosis and its cause
Excessive curvature of lower spine
caused by misaligned vertebrae
Define scoliosis and its causes
Lateral deviation of spine with/without rotation
can be idiopathic, systemic conditions (eg cerebral palsy), or indirect conditions
Define strain and where it occurs
tearing or stretching of a muscle or tendon
occurs anywhere in body, commonly lower back or neck (whiplash)
Define Sprain
tearing of a ligament
most common in ankle, also wrist, elbow, and knee
Define avulsion
complete separation of ligament from a bone
(Full sprain)
What is osteoporosis? What’s the general process?
It’s the decrease in mineralized bone mass. Old bone is reabsorbed faster than new bone is produced, causing low density
How does osteoporosis change with age?
Peak bone mass at 30yo
We have less active osteoblasts as we age
can be present for ears before fracture
Not always an age disease (not all old people have it)
What is post-menopausal osteoporosis? How does estrogen affect it?
In women, most bone density is lost in years just after menopause
estrogen inhibits osteoclast activities by decreasing cytokine production and increasing number of cells for bone reabsorption.
How does osteoporosis affect men vs women?
testosterone and estrogen are bone protecting hormones.
These hormones decrease more gradually in men than women, so bone loss is slower in men
Men also start with denser bones so it hits them later in life
What are the risk factors of osteoporosis? What do they do?
Long term corticosteroid use (reduce bone formation)
Endocrine disorders (increase bone reabsorption)
alcoholism (directly inhibits osteoblasts)
What are the clinical manifestations of osteoporosis?
kyphosis: hunched back
loss of height
Common fractures in spongy and porous bone
fractures in long bones (femur, hip, radius, ribs, and vertebrae)
Define osteomyelitis
An infectious bone disease
What are the 2 types of osteomyelitis? What are their causes?
Exogenous osteo: most common, caused by pathogens from open wounds
Hematogenous osteo: caused by pathogens in blood from infection in the body
How does osteomyelitis stages affect children?
1, affects area close to growth plate in long bones
2. exudate forms in bone and under periosteum, cutting blood supply and bone death
3. When periosteum lifts, osteoblasts are stimulated
Define sequestrum and involucrum
when exudate cuts off blood supply and causes bone necrosis
when osteoblasts lay layers of bone on top of sequestrum
How does osteomyelitis affect adults?
long bones lose conditions that favour bacterial attachment, affecting the axial skeleton
What is osteoarthritis? is it autoimmune?
an age-progressive, inflammatory, degenerative joint disorder
Not autoimmune in nature
What are the causes of osteoarthritis?
Primary: intrinsic defects in cartilage (natural variation)
Secondary: congenital joint defects, trauma/injury, crystal deposits, wear & tear, inflammatory diseases
How is articular cartilage lost
- in early disease, cartilage flakes off, underlying cracks develop
- Exposed bone hardens, may develop cysts
- cartilage may grow out of joint and alter the anatomy
- thus may break and enter synovial cavity
- joint capsule becomes thicker and stick to underlying bone, restricting movement.
What are the clinical manifestations of osteoarthritis?
appears in 50’s - 60’s
pain in joints
pain, stiffness, swelling, joint deformity
limited range of motion
creaking/grating sounds with movement
What is inflammatory joint disease?
inflammatory damage in synovial membrane or cartilage by systemic signs of inflammation
Describe the differences between infectious and non-infectious joint disease.
Inf: Caused by pathogens through wound or blood
Non: most common
caused by immune reactions or crystal deposition
Describe rheumatoid arthritis and its causes
chronic, systemic, inflammatory autoimmune disease known for joint swelling, tenderness, and destruction of synovial joints
Causes unknown, possibly genetic with inflammatory problems.
What body parts/tissues are affected by Rheum. Arthritis?
fingers, wrists, elbows, feet, ankles, and knees
first tissue us synovial membrane, then articular cartilage, joint capsule, and surrounding tissue
What factors are involved in Rheum. arthritis?
involves “rheumatoid factors” which are antibodies that react to host antibodies present in the synovial membrane.
What has to happen to start producing RF’s?
An unknown antigen must be found in the synovial tissue and an immune response is triggered
What are the clinical manifestations of Rheum. arthritis?
General inflammation: fever, fatigue, weakness
painful, tender, stiff joints for 1 hour
loss of range, possible deformities
loss of mobility -> atrophy of surrounding muscle
What is ankylosing spondylitis? Where does it start?
chronic, systemic inflammatory disease of joints in vertebral column
starts at sacroiliac joints and works up to smaller spinal joints
Who does A. Spondylitis affect? What are the manifestations?
Mostly affects men aged 15-40
pain, progressive stiffness and fusion of spinal column
What are the stages of disease progression?
- fibrocartilage in vertebral joints are inflamed
- damage occurs from macrophages and lymphocytes
- Fibroblasts repair damage, secrete collagen which ossifies
- Joints fuse together
Describe club foot. What are causes and corrections?
one or both feet are turn in and down in babies
can be positional, idiopathic, or from another syndrome
Can be corrected by manipulation and casts
Describe developmental dysplasia of the hips
Imperfect development of hip joint, ranging from loose to dislocation
Correctable in 1st month after birth, otherwise surgery is required
