Bone/Joints Flashcards
Impaired endochondral ossification in developing LONG BONES
Body habitus is out of proportion (shortened legs/arms/small face with normal trunk/cranium)
Achondroplasia (dwarfism)
Trunk/upper body = normal = intermembraneous ossification
Bones easily fx, often w/ multiple broken bones
Blue sclera
Defect in type 1 collagen (autosomal dominant disorder)
osteogenesis imperfecta
Brittle bone dz (other deformities = bowed legs/loose joints/weak teeth)
(may initially be confused for child abuse)
bacterial infxn of bones (usually staph a)
How do adults/children differ?
Osteomyelitis
Adults = usually comp of open fx or sx (infxn elsewhere spreads to bone)
Children = bacteremia seeding of metaphysis (potentially damaging the growth plate)
Tx = high dose abx, surgical cleanout/repair
Risk factors for osteoporosis
Age/gender (elderly women)
Decreased estrogen
Decreased mobility (chronic dz/post-trauma)
Poor diet/malabsoprtion
Clincal features of osteoporosis?
Femoral neck fx (**mortaility up to 50% within 1 year)
Vertebral bdoy fx (associated w/ kyphosis/dowager’s hump)
[DEXA scan shows reduced mineral bone density]
Tx for osteoporosis?
Meds (bisphosphates (dronates, dronic), estrogen)
Exercise
Proper diet (calcium, vitamin D)
Specific term for softening of bones in children due to inadequate calcium mineralization
Clinical features = bowlegs
Tx = Vit D,calcium, phosphorus
Rickets (osteomalacia)
Malnutrition/lack of sunlight contribute
Irregular bone restructuring leading to thickening/deformity
Typically affects skull, proximal femur, axial skeleton (often bowlegs)
Xray = honeycomb/cottonwool appearance
Osteitis deformans (Paget’s dz)
Tx = bisphosphonates (alenDRONATE, ibanDRONATE, zoleDRONIC acid)
Hypervascular around affected bone SO high risk for blood loss during ortho sx
Healing process for bones?
- Hematoma (2-3 days, chondroblasts/osteoblasts appear)
- Fibrocartilage (one week, fibroblasts/osteoblastsbuild trabeculae)
- Boney callus (2-4 weeks)
- Remodeling (occurs ONLY AFTER NORMAL MVMT RESUMES)
Factors promoting fracture healing?
IMMOBILIZAITON
ALIGNMENT
good blood supply
good diete
Involves wt bearing joints (knees, hips, vertebra) and fingers
JOINT SPACE NARROWING
OSTEOPHYTES
Initial stiffness/pain for 15 mins then fades
Joint may become tneder/enlarged BUT REMAINS COOL TO TOUCH (i.e., not inflammatory)
Osteoarthritis/DJD (Most common joint dz)
Finger nodules = Bouchard’s (PIP) and Heberden’s nodes (DIP)
tx = remain active and NSAIDs
Erodes articular cartilage/bone -> immobilization
CHRONIC SYMMETRICAL JOINT INFLAMMATION
Common in small joints of wrist/hand/proximal finger
Ulnar devation and finger z-deformity
(RARELY LARGE JOINTS, spares wt bearing axial skeleton)
RA
Tx = NSAIDs to slow progression
Uric acid crystals + ETOH abuse?
Tx?
Gout
NSAIDs (indomethacin)
Podagra?
2-3 days of intense pn, swlling, redness of great toe (1MTP)
May also invole ANKLE, knee, wrist
Gout (birefringent crystals)
Chronic hyperuricemia might lead to?
Tophi ( on ear auricle, olecranon, patella)
Uric acid renal stones
Secondary bone tumors 10x more common than primary
check
More common in males
Long bone tumor -> soft tissue
“Sunburst” and “onion skin”
Highly malignant; blood metz, Nearly 100% fatal w/o tx
Ewing’s sarcoma
MOST COMMON PRIMARY BONE CANCER
Long bones… half of which are near knee (often hematogenously spread to lungs)
Osteosarcoma
**35-60 year-olds
Cartilage tumor in the axial skeleton (pelvis, vertebra)
Chondrosarcoma
Rare dz
Autoimmune antibodies to Ach receptors at NMJ… decreases nerve impulses, which manifests as easily fatiguable muscles
MUSCLE WEAKNESS LATER IN DAY
PTOSIS, BLAND FACIAL EXPRESSION
What disease? What populations
Myasthenia gravis
Women 20-35, men 50-60
Test for Ach antibodies… dose w/ ACEI, muscle weakness should improve
Tx = symptomatic
Most common muscular dystrophy?
Males… early childhood onset (3-5 y/o)
Affects pelvic girdle/lower extremity
Gower’s sign?
Duchenne’s muscular dystrophy
Gower’s sign = using arms to lift torso
Testing = genetic (CK is elevated, BUT CK is elevated in all dystrophies)
Tx = corticosteroids (No cure, early death)
Most common childhoold muscle weakness d/o
Floppy child syndorme (hypotonia)
Delay reaching motor/mvmt milestones
Cerebral palsy
Acquired myopathies include?
Diabetic myopathy = chronic hypoperfusion, peripheral nerve dysfxn
Cancer myopathy = paraneoplastic syndrome
Rupture/ncerosis of striated muscle due typically to trauma (impact, crush, perfusion-reperfusion) or overuse
Cylce of more edema -> more entrapment
May lead to compartment syndrome
rhabdo
Clinical features = muscle pain (myalgia) and myoglobinuria (dark urine)
Labs = elevated K (-> arrhythmias) and CK-MM***
Tx?
Rhabdo
Tx = large volume IV fluid to dilute myoglobin/K
(extreme cases may require dialysis)
What are the 5 p’s of compartment syndrome?
increasing pressure in muscle compartment begins impeding blood flow
Pain (OUT OF PROPORTION) Paresthesia Pallor Paralysis Pulselessness (late finding...)
When shoudl a fasciotomy be performed for compartment syndrome?
intracompartmental pressure should be 30-40 mm Hg less than DBP… if ICP-DBP gap is less than 30 -> fasciotomy
benign
common
slow-growing
mobile
lipoma
can remove for cosmesis
cancerous
Malignant fatty tumor (grows rapidly)
Biospy to confirm
Tx = radiation/chemo
liposarcoma
