Final Flashcards
What is does plastic rags correlate with?
The etiologies that may cause an avascular necrosis
PLASTIC RAGS
Pancreatitis, pregnancy Lupus Alcoholism, atherosclerosis Steroids Idiopathic, infection Caisson disease, collagen disease Rheumatoid arthritis, radiation Amyloid Gaucher disease Sickle cell disease, spontaneous
4 stages of ANV
Avascular (death of bone)
Revascularization (angiogenesis, creeping substitution, fibrosis, cystic changes, bony fragmentation)
Repair/remodel
Deformity
AVN has affinity for what area of bone
Epiphyseal
Femur and humeral head**
Radiographic findings of AVN
-Collapse of articular cortex (loss of smooth contour/flattening and impaction fracture)
-fragmentation
-mottled trabecular pattern (thick over AVN)
-sclerosis
-subcontractors cysts
-subchondral fractures
(***crescent sign aka rim sign)
Chandler’s disease
AVN of femoral head in adults
XRAY findings of chandler’s disease
- Crescent/rim sign (thin radiolucency at super weight bearing cortex)
- Bite sign- wedge shaped necrotic area at anterior superior margin
- Snow cap sign (dense spot
- fragmentation/impaction FD
- sclerosis/cystic changes
- mottled bone density
- Mushroom deformity
- MRI shows decreased intensity
XRAY findings of healed chandler’s disease
Articular deformity Hanging rope sign- thing sclerotic line transverses femoral neck Trochanteric overgrowth (greater trochanter should NOT be above femoral head)
Leg calve perthes disease
AVN of femoral capital epiphysis in kid before closure of growth plate
XRAY findings in leggings calve perthes disease
ST swelling(increased TDD- normal 9-11mm)
Small epiphysis
Lateral displacement of ossification center
Small obturator foramen
Flattening/fissuring of ossification center
Widened physis
DDX of legg calve perthes disease
Congenital hip dysplasia (check for putt is triad—small epiphysis, lateral femur displacement, and increased acetabular angle)
SCFE-use klines line(doesnt pass through metaphysis)
Osteochondrosis dessicans
Focal subchondral infarction (AVN) of sub-articular bone
Where is osteochondrosis dessicans MC? Age?
Knee (lateral aspect of medial femoral condole)
11-20
MC in Males
Akas for avascular necrosis
Osteonecrosis
Osteochondrosis
Is there decreased joint space with an AVN?
No.
If decreased—> Ddx DJD
Whats bone/marrow death called at epiphysis? Metaphysis? Diaphysis?
E: ANV
M/D: bone infarction
What is an AVN in the femoral head in a child called? Adult?
Child: leg calve perthes
Adult: chandlers
Stats on leg calve perthes
Mc 4-8years
5:1 boys
S/s groin pain, limping, decreased ROM
XRAY findings during avascular phase of LCP? (0-12months)
Capsular distention
Increased joint space
Increased tear drop distance
Small epiphysis
XRAY findings during revascularization of LCP
Flat, small epiphysis Fragmentation Snow cap (sclerosis) Increased cortical density Metaphyseal cysts Crescent sign Wide short femoral neck
MC areas for osteochondrosis dissecans
- Knee (lateral aspect of medial femoral condyle 85%)
- humeral head
- capitellum of elbow
- talus (medial aspect of talar dome)
XRAY of osteochondrosis dissecans
- concave radiolucent defect <2cm
- may detach—>l joint mouse
Spontaneous osteonecrosis
-idiopathic AVN of the aged knee
Associated with medial meniscal lesions!
Osgood schlatter’s
Fragmentation of the apophysis of the tibial tuberosity
XRAY/diagnosis of osgood schlatter’s
Clinical
Localized pain, tenderness and swelling over tibial tuberosity.
**fragmentation may be normal. Requires pain/swelling to diagnose
11-15yrs
Ddx of osgood schlatter’s on XRAY
- normal-separate ossification centers
- avulsion Fx-involve entire tubercle
- sindig-larsen-Johansson-involve inferior pole of patella too
Sindig-Larsen-johanssen
Fragmentation of apophysis of tibial tuberosity
+
Involved inferior pole of the patella
MRI for osgood schlatter’s
Dark T1
Bright T2
(Edema)
Freiburgs disease
AVN of metatarsal head
MC 2nd
MC F 13-18 (heels?)
XRAY of freiburgs
AVN of metatarsal head
Collapse of articular surface (concave).
Density/cystic changes
Joint fine—end of bone is not.
Keinbocks disease
AVN of lunate
Stats of keinbocks disease
20-40
MC in manual labor jobs and males
Keinbocks disease is associated with what
Negative ulnar variance (short ulna)
XRAY of keinbocks
AVN of lunate
-Negative ulnar variance
-Initially increased density then…
-Flattening, collapse, fragmentation
(Sclerotic/lucent changes)
-Unsure—> MRI—> low signal= AVN
May see signet ring with keinbocks disease which may be Ddx for what? And what’s the difference
Ddx: rotators subluxation of the scaphoid.
It is NOT RSS because there is no terry Thomas sign seen (increased distance)
Kohler’s disease
AVN of tarsal navicular
Kohler’s disease Ddx?
Normal
Increased density may be normal during development. Compare to other side. If no pain=Normal
If pain=kohler’s
XRAY of kohler’s
Flat Small Dense Homogenous sclerosis Collapse/fragmentation
Scheuermann’s disease. Etiology?
Likely trauma
Most likely not necrosis
Scheuermanns disease
Abnormality of discovertebral junction
Must include 3 continuous vertebra
XRAY of scheuermanns
T and L spine
- Anterior body wedging
- irregular end plates
- decreased disc space
- increased kyphosis
- schmorl’s nodes
Juvenile discogenic disease
T-L scheuermann’s disease
Does not required 3 continuous vertebra
Inactive vs active scheuermanns
Inactive- done growing
Active-still growing
Severs disease
Sclerosis/fragmentation of calcaneal apophysis
***represents normal anatomy
-if pain—> calcaneal apophysitis
Calcified medullary infarct
Serpiginous region of calcification within the medullary region of bone
Usually due to arteriosclerosis
Ddx of calcified medullary infarct
Chondrosarcoma (PAIN)
Enchondroma
Sickle cell disease
Genetic disorder affecting RBC
MC hemolytic anemia
MC in AA
Sickle shaped blood leads to hypoxia, AVN, retarded growth and marrow hyperplasia
People with sickle cell disease are predisposed to what infections
Salmonella osteomyelitis infections
XRAY findings of sickle cell anemia
- Lincoln log/H shaped vertebra
- hair on end skull
- osteopenia
- marrow hyperplasia (widened diploid space)
- coarseness trabeculation
- long bone under-tabulation (Erlenmeyer flask deformity)
Thalassemia
Genetic RBC disorder causing abnormal hemoglobin
Presents with fatigue, splenomegaly, cardiomegaly and gallstones
XRAY of thalassemia
- marrow hyperplasia
- extramedullary hematopoiesis
- maxillary overgrowth (rodent facies)
- hair on end skull
- widened diploic space)
- coarseness honeycomb trabeculation
- erlenmeyer flask deformity
- osteopenia
Honeycomb coarsened trabeculation-what and with what
With thalassemia
Cystic changes to bones of hand
Osteopenia/thin cortex
Accentuated trabeculation
Hemophilia
X chromosome bleeding disorder
Females carry but it manifests in men
XRAY of hemophilia
- radiodense effusion
- osteopenia
- square femoral condyles
- epiphyseal overgrowth
- wide inter articular notch
- irregular juxta-articular surfaces and swelling
Wide intercondylar notch and irregular juxta-articular surfaces with epiphyseal overgrowth
Hemophilia
Leukemia
Malignant proliferation of WBC’s
XRAY of leukemia
- radiolucent su metaphyseal bands
- osteopenia
- osteolytic destruction of long bone metaphysis and diaphysis
- periosteal Rx
- growth arrest lines
What may su metaphyseal bands be seen in?
Neuroblastoma
Scurvy
Syphilis
Severe systemic diseases
Cellulitis
Infection of skin, subcutaneous fat or connective tissue
Osteomyelitis
Infection of bone or marrow spaces
Septic arthritis
Infection of joint/synovial tissue and articular surfaces
MC organism for infection
Staph Aureus
MC route of dissemination for infection
Hematogenous
Drug addicts and areas of infection MC
“S joints”
Spine
SI
Symphysis pubis
Sternoclavicular
Infant/young adults vs adults in onset of infections
Infant/young adult: acute process
Adults: insidious
Infantile pattern of infection
Metaphyseal & diaphyseal vessels penetrate the physis (through GP)
Septic arthritis and osteomyelitis
Childhood pattern of infection
Metaphyseal vessels do not penetrate physis. Separate epiphysis blood supply.
= tend to spare epiphysis and joint (osteomyelitis)
Adult pattern of infection
Metaphyseal vessels penetrate the vanishing physis re-establishing connection with subarticular bone (through the growth plate)
=osteomyelitis and septic arthritis
Most common locations for infection
Venous stasis areas
Knee Hip Ankle (distal tibia) Shoulder Spine
Infections infect the joint in what age categories and spare the joint in what age categories?
Infect the joint aka: septic arthritis and osteomyelitis
Infant and adult
Infect only bone aka osteomyelitis
Children
Two types of infections
Suppurations (pus) -staph
Non-suppurative - TB
Suppurative osteomyelitis
Bone marrow infection by any nonTB organism.
MC Staph Aureus
XRAY findings for latent (1-10 days) of infection
Little to no radiographic findings
ST edema
Osteopenia
XRAY findings at early stage of infection (10-21 days)
- ST swelling
- osteopenia
XRAY findings for middle stage infection (weeks)
- moth-eaten/permeating destructive changes—that may cross anatomical border
- periosteal rx
Xray findings for late stage infections (months)
- cortical destruction
- sclerosis
- cloaca
- sequestrum
- ankylosis
- involucrum
- loss of joint space
Xray findings for septic arthritis (joint-synovial/articular surfaces)
Joint effusion Osteoporosis Erosions Joint space loss Lytic destruction that crosses joint space
Sequestrum
Chalky white area representing isolated dead bone
Cortical and medullary infarcts
Involucrum
Chronic periosteal rx where pus lifts the periosteum and causes new bone formation to try to wall off the infection
Lytic and destructive changes
Cloaca
Opening in an involucrum where a squamous cell carcinoma can develop —> marjolin’s ulcer
Common in feet of diabetic
Bony collar
Chronic periosteal response
Seen with infections and involucrum
Marjolin’s ulcer
Squamous cell carcinoma within the channel of a cloaca during an infection
Brodies abscess
-localized intro osseous abcess with suppurative osteomyelitis
S/s of Brodie’s abscess
- local pain worse at night relieved by aspirin
- likes metaphysis
- nidus <1cm
Ddx of Brodie’s abscess
Osteoid osteoma
Brodies: redness, fever, cross joint space
MC location for Brodie’s abscess
Metaphysis
Distal tibia
Spinal infection origin and progression in adults and in children
Child: start in the disc bc it’s still vascular and then spread to the vertebral bodies
Adults: starts in anterior vertebral endplates and then goes to the disc with vertebral collapse
S/s of septic arthritis
- joint effusion
- juxta-articular osteoporosis
- erosions
- joint space loss
- lytic destruction crossing joints
Unilateral sacroilitis think? Order?
Infection
CBC and HLA-B27
In spinal infections where is the most common
Lumbar spine
S/s of spinal infection on xray
Increased RPI, RTI
-paraspinal like deflection
Psoas abscess
End plate and disc destruction
Erosion at anterior vertebral body with ill defined end plates, only one joint and decreased disc height
Spondylodiscitis (bone and disc)
Imaging for infections: plain film, nuclear scintigraphy, CT MRI
Plain: not sensitive. Takes 3-4 weeks for osteomyelitis
Nuclear scintigraphy: bone scan: very sensitive. Technetium. Positive within hours
CT: good for hard to see areas like spine, pelvis, sternum
MRI: best! More sensitive for bone marrow. Precedes bone scan.
Dark T1, Bright T2=infection
(NOT MODIC CHANGE THO)
Osteomyelitis findings on an MRI
Dark T1
Bright T2
Differentiating infection vs DDD
Bright T2 = infection
Dark T2= DDD
What is the MC cause of infection-related death worldwide
TB
Primary vs secondary TB
Primary= silent clinically
Secondary= disseminates from the lungs and can infect the spine
-T/L junction. Common to see in multiple levels bc it “drips” down the spine
XRAY findings for TB
Similar to osteomyelitis but slow growth
- affects multiple levels
- paraspinal cold abscesses with calcification
- calcified or obliterated psoas major
- gibbous formation: acute kyphotic angle
Infections
____usually affects one joint/level. ____ usually affects multiple levels
Staph Aureus (suppurative osteomyelitis)
TB
Where does adult TB infection usually start
Anterior endplate region
What is the earliest radiographic finding of TB
Disc space narrowing
MRI findings with TB
Dark T1
Bright T2
Gibbous formation. What is it and seen with what?
TB
An acute kyphotic angle created at the TL junction due to bony destruction
Phemister’s triad
seen with TB septic arthritis
- juxtarticular osteoporosis
- marginal erosions
- slow joint space loss (months/years)
TB septic arthritis
Phemister’s triad
- juxtarticular osteoporosis
- marginal erosions
- slow joint space loss (years)
_______MC location in suppurative infection and _______MC location for TB
Extremities-non
Skeletal-TB
_______ involves multiple levels with paraspinal cold abcess vs _______ only affects one level
TB/non-suppurative=multiple
Suppurative=one level
______has slow progression of joint destruction whereas ______has a faster progression
TB/non-suppurative= slow
Suppurative= fast
_______has a poorer response to therapies vs ________
TB/non-suppurative = poor (long term antibiotics)
Suppurative= good response to antibiotics
