Ortho: RAD FX Flashcards
(29 cards)
What is the epiphysis?
The end of growing bone.
Initially composed of cartilage
Gradually ossifies
Eventually fuses with the end of the growth period
what is the physics?
Growth Plate
Bone growth center
Layers of maturing cartilage and developing bone
what is the ZPC?
Junction of physis and metaphysis
Region of calcification of the physis cartilage
Precursor to bone formation
Side of physis closest to the metaphysis
what is the metaphysis?
Junction between the ZPC and diaphysis
Most metabolically active
Common site for tumors and infection
what is the diaphysis?
Between both methaphyses in long bone
Longest part of the bone
what is the cortex?
Strongest and most dense part of the bone
how is cortical bone organized?
Lamellar bone organized concentrically to form osteons, each with a Haversian canal at its center
Canal contains blood vessels
Osteocytes occupy lacunae (Dark spots)
where is the bone marrow contained?
MEDULLA = MARROW (spongy bone)
Internal cavity of bone
Traversed by thin trabeculae
Contains the bone marrow
what is the periosteum?
Thin membrane of tissue that envelopes the diaphysis and metaphysis
Histologically divided into two layers
Outer fibrous
Inner cambium
what is “Large force applied over a large area”
crush
what is “Large force applied over a small area”
penetrating
what is “Small force applied to a small area (nightstick)”
tapping fracture
what are the different types of fractures?
Transverse Oblique Spiral Comminuted (Segmental or Butterfly) Impacted
what is alignment?
Alignment: The relationship of the long axes of the fragments of a long bone to one another.
what is apposition?
Apposition: The relationship of the fracture fragments to their normal anatomic location
what is a stable versus unstable fracture:
Stable Fracture: Does not have a tendency to displace after reduction
Torus fracture
Unstable Fracture: Tends to displace
Colles Fracture
what is simple and compound?
Simple (Closed) – Overlying skin intact
Compound (Open) – Overlying skin broken
what is complicated and uncomplicated?
Uncomplicated – Only minimal soft tissue injury
Complicated – Associated with neurovascular, visceral, ligamentous or muscular damage. (also intra-articular)
Salter-Harris Classification: Salter Harris I
Fracture through the physis
May be displaced or undisplaced
May not be obvious on initial x-ray
Circumferential tenderness along physeal area
Distal tibia and fibula common
Similar presentation to ankle sprain, no ligamentous tenderness
Salter-Harris Classification: Salter Harris II
Fracture through the physis and extends into metaphysis
75% of all physeal injuries
Undisplaced SHII fractures generally do not cause growth disturbances
Salter-Harris Classification: Salter Harris III
Fracture through physis extending into epiphysis
Intra-articular fractures that must be accurately reduced
Older children with partially-closed physes
Early referral to orthopedics imperative
Salter-Harris Classification: Salter IV
Fracture through the physis and into both the epiphysis and metaphysis Need accurate reduction Prevent bone bridging across physis Can lead to partial growth arrest Early referral imperative
Salter-Harris Classification: Salter V
Crush injury to the growth plate
1% of all physeal injuries, but MOST SERIOUS!
May not be clearly visible on initial films
Comparison views
Often diagnosed in retrospect when growth arrest is noted
What is Wolff’s Law?
Bone is deposited and resorbed in accordance with the stresses placed upon it.
It responds dynamically to stress by altering its internal architecture