orthopedic pathology (fractures) Flashcards
fracture
break/defect in bone
“broken bone”
bery common
fracture accompanied by soft tissue injury
The physical force that is required to break a bone practically always produces some soft tissue injury
Difficult to determine the extent of soft tissue injury
causes
Trauma or sudden force
Direct – a bone breaks at the point of impact
Indirect – bone breaks some distance from the force (closed chain?)
other cause
Overuse or repeated wear
Stress fracture
pathologies as acause
Pathologies
Osteoporosis,
osteopenia (?)
tumours,
local infection
or bone cysts
Can cause weakening of bone
symptoms fracture
Unnatural mobility
Muscle splinting
Visible deformity
Pain (SHARP)
Bleeding
Swelling, bruising
Decreased function
Internal organ damage
Shock
daignosis
Imaging
X-ray
CT
MRI
Ultrasound (not as common)
Physical examination:
Fracture Screen:
Four step test
Torsion test (resisted isometric contraction)
Palpation (bony prominences)
Percussion/tuning fork (based on sound pattern/pain w/ fork distal to site?)
treatment
immobilization
(cast/splint)
surgical reduction
(screws, wires, metal plates)
Meds
NSAIDS (advil, naproxen, etc)
healing
Depends on:
The amount of damage incurred
Amount of movement at fracture site
Concurrent disease
Age
Overall health status
Complications
complications (early = within first few weeks)
Soft tissue injuries (muscles, ligaments, etc)
Acute compartment syndrome (within 48 hours):
Most commonly in forearm or leg
Swelling/bleeding increases pressure within fascial compartment
Cycle of reduced circulation -> ischemia -> edema -> reduced circulation
–>Leading to necrosis and gangrene
(Medical emergency)
complications (early)
Nerve compression
Bone/soft tissue infection
fever, pain, edema, pus
Deep vein thrombosis
(Blood clot in deep vein)
Cast dermatitis (allergic reaction)
Pressure or plaster sore
(ischemia over bony prominence)
late complications (few weeks to years)
Nerve compression or entrapment
Joint stiffness
Disuse atrophy
Disuse osteoporosis
Myositis ossificans
Metal plates may cause discomfort forever
other late compications
Delayed union:
Bone does not unite within expected time frame
Via inadequate circulation, insufficient splinting, infection
non-union
Failure of bone to heal before repair process finishes
Due to large gap, bone destruction, bone loss
rebreak bone and join together surgically so they form union and heal as one structure
malunion
union occurs but not correctly (offset, at an angle etc.)
Can lead to altered biomechanics, tendinitis, bursitis, osteoarthritis
other late complicaitons
avascular necrosis:
Tissue ischemia
via impaired vascular flow
Minimum of 2 hours of anoxia required for permanent loss of bone tissue
(May be secondary to trauma or thrombosis)
note tissue hypoxia survival time
Brain <3 min
Kidney and liver 15-20 min
Skeletal muscle 60-90 min
Vascular smooth muscle 24-72 h
Hair and nails Several days
osteonecrosis (same as avascular necrosis of bone????)
avascular necrosis of bone
Occurs in bones that are poorly vascularized
scaphoid, neck of femur, talus, lunate
Ischemia occurs shortly after fracture, but necrosis may not be noticed on x-ray for weeks
bone healing stage 1 (SEVERAL WEEKS)
fracture hematoma
Blood vessels are damaged and cause a mass of blood to form around Fx (Fx hematoma)
Forms 6 to 8 hours after injury
Lack of blood flow causes nearby bone cells to die, which creates additional swelling/inflammation.
Phagocytes and Osteoclasts clean up dead/damaged tissue around Fx
This stage may last up to several weeks.
stage 2
FC callus formation (3 weeks)
Fibroblasts invade fracture site and produce collagen fibers.
Chondroblasts invade fracture site and produce fibrocartilage
= SOFT CALLUS (FC callus)
helps to bridge the broken edge of the bones.
Formation of a soft callus takes about 3 weeks
chondrocytes and collagen
The pericellular region immediately surrounding the chondrocyte contains type VI collagen
(referring to a different area of cartilage, not FC callus, but FC callus also has collagen)
stage 3 (3-4 months)
bony callus
Osteogenic cells develop into osteoblasts and produce spongy bone trabeculae
The trabeculae join living and dead bone fragments together, replacing the fibrocartilage.
This new callus is referred to as a hard callus (bony callus)
The bony callus lasts about 3 to 4 months.
stage 4
Bone remodeling is a slow process that may last 6-9 years, which is 70% of the total healing time. In the remodeling, osteoclasts (cells that break down bone tissue) resorb the trabecular bone, and osteoblasts deposit compact bone.
stage 4 …
Bone remodeling of the callus
Remaining dead portions of bone are reabsorbed by osteoclasts.
Compact bone replaces around spongy
Realignment along lines of stress (Wolff’s law)
general classification of fractures
via:
1. Site
- Extent
- Configuration
- Relationship of fragments to each other
- Relationship of fragments to external environment
1) site
Diaphyseal
Metaphyseal
Epiphyseal
Intra-Articular
(Articular surface)
Fracture-dislocation
2) extent
Complete
Bone is broken into two or more pieces
Incomplete
Bone is bent or cracked, but (most of?) the periosteum remains intact, which allows the bone to remain whole
E.g.
Compression
Greenstick
Stress/Hairline
compression fracture
The bone is crushed
Occur in cancellous (spongy) bone
E.g.
Vertebral body
greenstick fracture
The bone is bent or partially broken
ound in children younger than 10 years old
–> Bones are more pliable than those of adults
stress/hairline fracture
Crack in the bone due to overuse or repetitive actions
common @
MOST COMMON TIBIA (50%)
MT (march fracture)
navicular
femur
pelvis
3) configuration
Linear
Parallel to the long axis of a bone
Transverse (chalkstick)
Right angle to the bone’s long axis
Oblique
Diagonal to a bone’s long axis
Spiral
at least one part of the bone has been twisted
Comminuted
Consists of two or more fragments
Avulsion
A ligament (or tendon) pulls a portion of the bone away from the bone itself
4) relationship of fragments to each other
Undisplaced
Fragment ends are in line with each other
Displaced
Fragment ends have moved and no longer line up
5) relationship of fragments to external environment
Closed/simple fracture
Skin is intact
Open/compound fracture
Ends of the bone have broken through the skin or into a body cavity; more prone to infection
“Closed fractures are easier to treat with better prognosis.”
named fractures
.
lower extremity named fractures
..
Galeazzi fracture
Fracture of radial shaft and dislocation of distal radioulnar joint
FOOSH
Monteggia Fracture
A fracture in the proximal part of the ulna with dislocation of the head of the radius
Colles Fracture
Transverse fracture of distal radius
Distal fragment rotates and displaces dorsally
FOOSH
“Dinner fork” deformity
Smith’s Fracture
Aka reverse Colles fracture
The distal fracture fragment is displaced ventrally (volar/palmar)
“spoon”
Barton’s Fracture
An intra-articular fracture of the distal radius with dislocation of the radiocarpal joint
Two types
Dorsal and palmar (Reverse Bartons’s)
FOOSH
Bennett’s Fracture
Intra-articular fracture of proximal 1st metacarpal with dislocation of CMC joint
Longitudinal force along the axis of the 1st MC when thumb is flexed
Reverse Bennett’s
5th MC (proximal)
Rolando Fracture
comminuted intra-articular fracture through the base of the first metacarpal bone
Fracture consisting of 3 distinct fragments
–> T or Y shaped
Boxer’s (Brawler’s) fracture
Fracture of the (distal?) 5th MC
Due to punching an object with a closed fist
Salter-Harris Fracture
Refers to any fracture that occurs through the growth plate.
More common in the upper extremity
Typically only happens in children (epiphyseal plate)
(Growth plates are weak, joint capsules are strong in comparison)
named fractures of lower extremity
..
Pott’s Fracture
One or both malleoli
Can also involve deltoid ligament rupture or avulsion to medial malleoli
Jones Fracture
Aka dancer’s fracture
Is an injury to the 5th metatarsal (PROXIMAL END)
Occurs at the proximal end (midfoot)
MOI: forceful inversion and plantar flexion
Maisonneuve Fracture
Spiral fracture of the PROXIMAL third of the fibula
associated with a tear of the DISTAL tibiofibular joint and interosseous membrane
Medial malleolus avulsion and possible rupture of the deltoid ligament (???)
Toddler’s Fracture
Aka childhood accidental spiral tibial fractures
(CAST fracture)
Occurs in children usually under 3 years old, but up to 8 years old
Involves the distal third to distal half of the tibia
Undisplaced and in a spiral pattern
Trimalleolar Fracture
A fracture of the ankle that involves the lateral malleolus, medial malleolus and the distal posterior aspect of the tibia
fractures of spine
..
skull fractures
linear fracture (most common
depressed fracture (high velocity impact by small object)
Jefferson Fracture
AKA Burst Fracture of the Atlas
Fracture(s) of anterior and/or posterior arches of C1
Compression injury
Usually MVA or diving injuries
Clay Shoveler’s Fracture
Avulsive fracture of the spinous process
Occurs typically between C6-T1, C7 being most common
MOI:
Hyperflexion of neck with contraction of erector muscles
Teardrop fracture
Usually occur in the cervical spine
Flexion Teardrop: Hyperflexion causes anterior vertebral body to compress and shear off an anterioinferior fragment.
Extension Teardrop: Hyperextension causes an avulsion fracture of the anterioinferior portion.
Usually very SEVERE and unstable:
Due to ligamentous disruption the spinal cord can be compromised, leading to paralysis
Compression Fracture
Combined flexion and axial compressive forces
Most common fracture of lumbar spine
(M/C at T12 and L1)
Commonly seen in patients with osteoporosis in C-spine
–> Dowager’s hump
Rib Fracture
via blunt or penetrating chest trauma.
Ribs 4-10 are most commonly fractured.
Upper 3 ribs require higher force impact
May lead to complications with internal organ injury
Flail Chest
When three of more contiguous ribs are fractured in two or more places.
MOI
High impact blunt trauma with severe anteroposterior compression.
