MSK Flashcards
What are major functions of bone?
Support Protection Movement Hormone Production Blood Cell Formation Triglyeride Fat Storage Mineral and growth factor storage
What are part of axial skeleton?
Skull
Vertebral column
Rib cage
What are parts of appendicular skeleton?
Upper limbs
Lower limbs
Girdles
What types of bone shapes are there?
Long bones - shaft and 2 ends
Short bones - roughly cube shaped
Flat bones - thin flattened and curved
Irregular bones - complicated shapes
Which bones undergo intramembranous ossification?
Cranial bones
Clavicle
‘flat bones’
When does intramembranous ossification occur?
In utero - before 8 weeks
Which bones undergo endochondral ossification
All bones below head (except classification)
when does endochondral ossification occur?
Around 2 months in utero
Which hormones regulate bone growth
hypothamalamus affects anterior pituitary gland
this secretes growth hormone, thyroid stimulating hormone and LH/FSH
T3 and T4 and calcitonin from thyroid gives negative feedback to stop secretion.
How much % of bone mass is recycled every week
5-7%
Means who new skeleton every 7-10 years
What are common causes of fractures?
Trauma
Osteoporosis
Overuse
What are symptoms of fracture?
Swelling/tenderness
Bruising
Deformity
What is treatment for broken bone?
Cast/Immobilsation Brace Traction External Fixation ORIF
What is buckle fracture
When 2 bones driven into each other
What are salter Harris fractures?
Involving the growth plate
SALT ER Type 1. Separated growth plate 2. Above growth plate 3. Lower than growth plate 4. Through growth plate 5. Erasure of growth plate (pressed together)
What are consequences of Salter Harris fracture?
Growth arrest and deformity - but not all physeal injuries have same risk of injury.
Which are most common salter Harris fracture?
type 2. 74% of all physeal fractures
What is osteogenesis imperfecta?
A defect where collagen is missing reduced or of low quality. Therefore not enough support for the minerals in the bone. Makes it weak and easy to fracture.
There are different types which determine how severe it is. e.g. OI type 2 may fracture in utero - most severe - may be life threatening
Type 1 mild
Type 3 severe
What are signs and symptoms of OI?
Range from mild to severe.
Fratures may occur easily -
Sclera of eyes may be blue coloured
Hypermobile joints
Poor dentistry
Bowing/altered bones
Hearing problems
How is OI diagnosed?
X-rays used to check bones
DEXA carried out to check bone density
No definitive test except genetic testing.
How is OI treated?
With pamidronate and zoledronic acid infusion.
Both type of bisphosphonate - prevents loss of bone mass.
Vit D may be given.
What is developmental dysplasia of the hip?
Hip instability which ranges from mild acetabular dysplasia to dislocation.
The hip socket is shallow and so the femoral head may slip in and out.
What is occurrence of DDH?
1-3% of newborns.
80% in girls.
How is DDH diagnosed?
Ultrasound up to 4.5 months.
X-rays as child older.
Clinically, limited hip abduction when hip is flexed to 90 degree.
What are causes of DDH?
Breach presentation
Connective tissue laxity.
Large for gestational age
Multiple pregnancy
Risks include family history.
What is treatment of DDH?
dynamic flextion-abduction othosis called pavlik harness or splinting.
Or spica cast.
If late then may need pelvis osteotomy.
What is consequence of DDH
possible premature degenerative joint disease.
