Musculoskeletal 3 Flashcards
(42 cards)
1
Q
lumbar spine
A
Plain films - AP, lateral – standard
Special views: lumbrosacral spot, oblique
Approach – ABC’S (alignment, bones, cartilage, soft tissue)
- Spinous process alignment (AP)
- Intrapedicular distance (AP)
- Transverse processes (AP)
- Vertebral body width (AP)
- Vertebral body height, width, cortex (Lateral)
- Posterior vertebral line (Lateral)
- Disc spaces (Lateral)
- Soft tissue (Both)
- Free stuff (Both)
2
Q
Bohler’s angle - calcaneus
A
- A=Superior surface of posterior tuberosity, subtalar articulation
- B=Superior tip of subtalar articular surface and anterior process
3
Q
patellar tendon rupture
A
-Cannot extend lower leg at knee
-High-riding patella
Effusion
-Mechanism: sudden muscle contraction (direction change) or direct blow
4
Q
the pelvis
A
-Single AP view is common
-Judet views - supine, hip 45d -acetabulum
-Inlet - 40d caudad - pelvic ring
-Outlet-40d cephal - sacroiliac
-CT has largely replaced
special views if fx suspected
5
Q
Alignment: the mortise
A
-The mortise is critical!
-When describing ankle fractures,
always comment on the mortise.
-Is it intact? Wide? Narrow? Where?
-Determines ligamentous disruption and overall stability of the ankle.
6
Q
hip dislocations
A
- 90% are posterior
- Femoral head lateral, superior to the acetabulum
- Lower extremity internally rotated and shortened
- Axial force along flexed hip and knee
- Sciatic nerve injury 10%
- Anterior Dislocation → External rotation, Shortened, Femoral head is inferior, medial
7
Q
Spondylolysis
A
- Bony defect of the pars interarticularis
- Non-displaced fracture
- L4-L5, L5-S1
- Repetitive stresses, congenital, kids
- Fracture results in a “collar” around neck of the “Scotty Dog”
- Lateral oblique view
8
Q
Burst fracture
A
- Axial load - jump, fall
- Comminuted, entire vertebral body, both anterior and middle columns
- Post vertebral line disruption
- Inter-pedicle space disruption
- Unstable=post column fx
- Fx fragment may have “retropulsion” into spinal canal and compress cord
- CT, MRI if neuro deficit
9
Q
thoracic spine
A
- AP, lateral standard views
- T1 – T12: all have ribs
- L1: transverse process
- Fractures less common (rib cage support)
- Most: compression fx’s
- Significant mechanism
-Fracture/dislocation: 60-70% spinal cord, injury - all get MRI
- CT for fracture
- MRI for spinal cord
10
Q
talus fracture
A
Uncommon – but serious
High force mechanism
Fracture/dislocation common
High risk AVN, malunion
ORIF
CT all talus fx’s
11
Q
Femoral shaft fractures
A
- High Energy/Force
- Pathologic fx?
- Displacement due to muscle contraction
- OR reduction, hardware common
- High risk of bleeding (femoral artery)
- High risk compartment syndrome
12
Q
chance fracture
A
- “Seatbelt fx” - hyperflexion, force
- Thoracolumbar junction
- Horizontal fx thru body, post arch, SP
- Ligamentous injury
- May have retropusion of fragments
- Unstable
13
Q
slipped capital femoral epiphysis
A
SCFE -Capital femoral epiphysis slips - posterior/lateral -10-15yo obese boys: hip/knee pain -Salter-Harris Type I injury -Risk for AVN
14
Q
tibial plateau - compression fx
A
Can be subtle! Easy to miss!
- Usually lateral plateau
- Increase in trabecular density – sclerotic
- Tibia lateral to femur
- Direct blow “fender fx”
- Osteoporosis - minor mechanism
- Effusion, can’t walk
15
Q
tibial pilon/plafond fracture
A
Fx of the Tibial Plafond
Comminuted Intraarticular Impacted
Vertical load - Jumpers
Unstable - Get CT scan
Plafond = “ceiling”. Fx of the “ceiling” of the ankle joint
16
Q
Spondylolisthesis
A
- Anterior slippage of the vertebral column relative to the vertebral body below it
- True: Fracture of pars interarticularis with displacement
- Pseudo: no pars interarticularis fx
- Usually a result of bilateral spondylolysis
- Most commonly occurs at the L3/4, 4/5 or L5-S1 level
- Results in spinal stenosis
17
Q
osgood-schlatter disease
A
- Micro-avulsion at insertion of patellar tendon at apophysis (cartilaginous tissue for tendon insertion)
- 10-12yo - when tibial tubercle ossifies
- Family hx same
- Pain, inflammation
- Rest, good prognosis
- Can also occur at calcaneus, navicular (foot)
18
Q
pelvis fractures: stable
A
- 2/3 of all pelvis fx’s
- Avulsions common in athletes
- Isolated ischium, pubic ramus - fall, osteoporosis
- Sacral - fall, direct blow
- Illiac wing – blunt, MVA: Duverney’s
19
Q
ankle xrays - the approach
A
- AABC’S (ABC = Adequacy, Alignment, Bones/Periosteum, Cartilage (joint space), Soft Tissue)
- Tibia, fibula, talus
- Malleoli - check medial, lat, posterior
- Mortise: ligament disruption - check width, symmetry
- Soft tissues
- Ottawa Ankle Rules
- Many Fx Classifications -Weber common
- Ligaments are key!
20
Q
Bohler’s and Gissane: calcaneus
A
- Decreased/Increased Bohler’s or Gissane’s Angle?
- Suspect fx
- Bohler’s commonly decreased
- Gissane’s commonly increased
21
Q
tibial plateau
A
- Bumper, dashboard - auto vs. ped, MVA
- Axial load, valgus force - jumpers
- High risk of ligamentous injury
- Order CT scan
- Most require ORIF
22
Q
true spondyloisthesis
A
-spinous process step-off above subluxed vertebral body w/ PI defect
23
Q
greenstick/torus fx’s
A
-Incomplete break in
cortex = greenstick fx
-Buckle, buldge, impaction along cortex = torus fx
-Common in kids: soft bones; radius/ulna
24
Q
hip fractures - proximal femur
A
- 250k/yr in US
- 20% mortality in elderly
- Trauma, osteoporosis, steroids
- Location and displacement: key
- Displaced neck, subcapital fx’s: High risk AVN femoral head, Garden Classification)
- ORIF: pins to total arthroplasty
- CT, MRI for fx’s, MRI occult fx’s
25
hip hardware
1. Screws – stabilize, realign hip and preserve anatomic angle. Non-displaced and incomplete fx’s with little risk for AVN
2. Dynamic hip screw – stabilize, realign hip and preserve anatomic angle. Fx’s with little risk of AVN
3. Hemiarthroplasty – proximal femur preserved, femoral head/neck replaced, cup inserted into acetabulum. Used if high risk AVN
4. Total hip arthroplasty – replace entire proximal femur, add cup for acetabulum. Widely displaced, high risk AVN, poor quality native bone
26
Pediatric wrist is special
Capitate/hamate
first to osssify
Spiral order
Roughly 1 carpal per year age up to age 7
Radial head epiphysis >age 3
Pisiform ~ age 12 – the last one
27
Trimalleolar fracture
- All 3 malleoli fx’d, including posterior
- (AKA: malleolus tertius)
- Unstable fracture
- Follow the cortical lines of both the tibia and fibula on lateral
28
calcaneus fracture
- Jumpers, axial load or fall from height
- Most common tarsal bone fracture
- Axial view calcaneus
- Decreased Bohler’s Angle, increased Gissane Angle
- Can be subtle! CT all
- Compression fx of lumbar spine common w/ these fx’s – axial load transfer. Get plain films L-spine too
29
Wedge compression fracture
- Hyperflexion, fall
- Osteoporosis, pathologic
- Loss of height anterior vertebral body only (anterior column)
- Posterior body height and post vertebral line intact
- >% loss height = >severity
- Common - 1 in 4 >75yrs
- CT to r/o Burst fx
30
Salter-Harris Classification
Type I:
- Fx through epiphyseal plate, w/ or w/o displacementof the epiphysis.
- Difficult to detect w/o displacement
Type II:
- Fx through epiphyseal plate and metaphysis
- Most common type; up to 75%
Type III:
-Fx through epiphyseal plate and epiphysis
Type IV:
-Fx through epiphyseal plate, epiphysis and metaphysis
Type V:
- Impaction fx involving all/part of the epiphyseal plate
- Most serious growth consequences
- Note: epiphyseal plate is also called the physis or growth plate
- It is the radiolucent area/space between the epiphysis and metaphysis
31
Base of 5th metatarsal
Jones Fx
- Base 5th MT shaft at least 1.5cm from styloid
- Direct blow, repeated activity, stress
- High incidence non-union - Cast, ORIF
Pseudo-jones Fx (avulsion fx @ tuberosity)
- Common - “Dancer’s Fx”
- Avulsion peroneus brevis tendon (aka: fibularis longus)
- Fracture at styloid of 5th MT
- Walking cast
32
Pediatric elbow ossification
When do the bones first appear on xray?
CRITOE
- Capitellum 1yr (1-8mo)
- Radial head 3yr (3-6yr)
- Internal (medial) epicondyle 5yr (3-7yr)
- Trochlea 7yr (7-10yr)
- Olecranon 9yr (8-10yr)
- External (lateral) epicondyle 11yr (11-12y)
33
legg-calve-perthes dz
LCP
-Avascular necrosis of
femoral head, epiphysis
-Flat, irregular, sclerotic
-Boys: 4:1 predominant
-Age 4-9 most common
-LCP is idiopathic
-”growing pains”
-Limp, hip pain, often
knee pain
34
Salter-Harris fracture classification
Growth plate fx’s
in children
Can affect growth,
bony development
Higher number =
worse prognosis
I-V for us
I-IX for pediatric
orthopedists
35
Maisonneuve fracture
```
Spiral fx proximal
fibula with:
-Wide medial mortise
-Medial malleolar fx
-Tibiofibular joint
widening (syndesmosis disruption)
-With or without distal
fibula fx (classic)
```
Check proximal
leg tenderness
in all ankle injuries!
36
Pediatric considerations
- Growth Plates
- Salter-Harris Classification
- Wrist ossification order
- Elbow ossification order - CRITOE
- Osgood-Schlatter
- Legg-Calve-Perthes
- Slipped Capital Femoral -Epiphysis
- Ossification = when bones actually form or when you can see them on xray
- Metaphasysis is the active part next to the growth plate
37
pseudospondylolisthesis
-step off below subluxation, PI intact
38
Bimalleolar fracture
- Lateral and medial malleoli fractures. Posterior malleolus intact.
- Unstable fracture with mortise (ligamentous) disruption
39
patellar dislocation
- Often clinically evident, may self reduce
- Majority are lateral
- Xray for patella fx post-reduction
- 30% w/ ligamentous, meniscus injury
40
Pelvis fractures: unstable
- Unstable = pelvic ring is disrupted in 2 or > places
- Diastasis = separation – SI joints or pubic symphysis
- High-risk injury - hemorrhage, pelvic organ injury
- The ring of the pelvis is fractured in 2 or more places – that alone makes it unstable
- High risk for hemorrhage! You can lose up to 2 liters of blood!
41
degenerative joint disease - spondylosis
- DJD, Osteoarthritis = Spondylosis
- Cortical sclerosis, disc space narrowing, spurs
- Ankylosing Spondylitis (bamboo spine)
42
Lisfranc fracture/dislocation
- Midfoot slide.
- Check: 1st, 2nd MT alignment w/ 1st and 2nd cuneiform:
- Check: 5th MT alignment w/ cuboid:
- Check: fx at proximal 2nd MT:
- Check: MT/cuboid spacing on AP/oblique
- Unstable
- ORIF
- Often the mechanism is extreme dorsiflexion at MTP joints – tip-toe position.
- Actual Lisfranc ligament is between first cuneiform and medial base of the second metatarsal bone
