Knee Tibia & Fibula

Question 1

What condition is likely the cause of these findings?

Answer 1

• Subchondral sclerosis with loss of medial joint space (non-uniform loss of joint space)
• Subchondral cysts & small osteophyte on medial side

→ Degenerative Arthritis → OA or DJD of medial femoral tibial jt

Question 2

Isolated degeneration of patellar-femoral joint should raise suspicion for what condition

Answer 2

CPPD (Deposition disease)

Question 3

Genu varus (bowlegged) is associated with what conditon?

Answer 3

Degenerative joint disease

Question 4

What condition is likely the cause of these findings?

Answer 4

Spiking of tibial spine - DJD

Question 5

What condition is likely the cause of these findings?

Answer 5

Question 6

What condition is likely the cause of these findings?

Answer 6

Circle in back is not inter-articular loose body

Question 7

What condition is likely the cause of these findings?

Answer 7

• loss of joint space, osteophytes

Question 8

Features of ____ include:

• Typically affects all 3 compartments of knee
• Soft tissue swelling & joint effusion
• Sclerosis absent or minimal
• Subchondral erosion & periarticular osteopenia
• Baker’s cyst can form in posterior medial knee

Answer 8

Rheumatoid Arthritis

Question 9

Genu valgus (knock-kneed) is associated with what condition

Answer 9

Rheumatoid Arthritis

Question 10

What condition is likely the cause of these findings of bilateral, symmetric uniform joint loss?

Answer 10

Rhuematoid Arthritis

Question 11

What condition is likely the cause of these findings?

Answer 11

Question 12

What condition is likely the cause of these findings?

Answer 12

Due to location at patello-femoral joint → CPPD

Question 13

Features of ____ include:

• Chondrocalcinosis of hyaline cartilage & fibrous cartilage (meniscus)
• Involves patello-femoral joint first (also typically involves lateral femoral tibial jt before medial)

Answer 13

CPPD (calcium pyrophosphate deposition disease)

Question 14

What condition is likely the cause of these findings?

Answer 14

Question 15

What condition is likely the cause of these findings?

Answer 15

CPPD (hyaline cartilage)

Question 16

What condition is likely the cause of these findings?

Answer 16

• Uniform loss of joint space
• Inflammatory arthritis with associated degenerative changes → Septic Arthritis or Juvenile Idiopathic Arthritis or Hemophilia if involving other joints in the body

Question 17

What condition is likely the cause of these findings?

Answer 17

Question 18

What condition is likely the cause of these findings?

Answer 18

• Sheet like calcification in tissues → DDX: Dermatomyositis, SLE or sclerotoma

Question 19

Features of ____ include:

• Overgrowth of epiphyses
• Squared inferior pole of the patella
• Widened intercondylar notch
• Increased soft tissue density around jointso
• Early degenerative joint disease & Osteoporosis
• Pseudotumor

Answer 19

Hemophilia

Question 20

What condition is likely the cause of these findings?

Answer 20

• Avulsion fx at lateral tibial plateau (Segond fx)
• Deepening of lateral femoral notch
• Joint effusion

Compression fx at femoral notch → specific for ACL tear

Question 21

What condition is likely the cause of these findings?

Answer 21

ACL tear

Question 22

What condition is likely the cause of these findings?

Answer 22

• Calcific density
• Fragment of subchondral bone at medial femoral condyle
• Osteochondritis dessecans

(Refer for MRI to look at cartilage)

Question 23

What condition is likely the cause of these findings?

Answer 23

Lateral tibial plateau fx

Question 24

Features of ____ include:

• Look for depression of lateral plateau articular surface
• Look for cortical disruption of proximal lateral tibial cortex

Answer 24

Lateral tibial plateau fx

Question 25

What condition is likely the cause of these findings?

Answer 25

- Solid periosteal reaction, cortical thickening at mid-diaphysis - Small linear lucency through region of cortical thickening - Thickening of soft tissues DDX: Fatigue (stress) fx or possible tumor such as osteoid osteoma

Question 26

What condition is likely the cause of these findings?

Answer 26

- Lucent lesion in proximal tibial metaphysis - Increased density, area of sclerosis around lucency DDX: Brodies abscess, less likely osteoblastoma and osteoid osteoma

Question 27

Features of ____ include: - Permeative/motheaten destruction w/ periosteal responses - Common in femur & tibia

Answer 27

Osteomyelitis

Question 28

What condition is likely the cause of these findings?

Answer 28

Question 29

What condition is likely the cause of these findings?

Answer 29

DDX for lucent metaphyseal bands: Leukemia, Rickets

Question 30

What DDX are likely the cause of these findings?

Answer 30

DDX: Tuberculous Arthritis, Septic Arthritis, Neuropathic Arthropathy

Question 31

What condition is likely the cause of these findings?

Answer 31

- Bone disease - osteoblastic appearence, increased density proximal tibial metaphysis to diaphysis - Periosteal responses - Aggressive DDX: Osteosarcoma, Ewing's Sarcoma, Osteomyelitis (Osteosarc most likely due to blastic appearence) Recommendations: oncological & MRI

Question 32

Features of ___ include: - Meatphyseal - Can be osteoblastic (MC), osteolytic or mixed - Periosteal reactions (spicula - Soft tissue extension

Answer 32

Osteosarcoma

Question 33

What condition is likely the cause of these findings?

Answer 33

Osteosarcoma

Question 34

What condition is likely the cause of these findings?

Answer 34

- Pedunculated exocytosis DX: Osteochondroma

Question 35

What condition is likely the cause of these findings?

Answer 35

Question 36

What condition is likely the cause of these findings?

Answer 36

Osteochondromatosis

Question 37

What condition is likely the cause of these findings?

Answer 37

- Lucency in medial metaphysis of tibia, well-defined by sclerosis - Soap bubble appearence DDX: Benign lesion most likely non-ossifying fibroma, could also be fibrous dysplasia

Question 38

Features of ____ include: - Eccentrically located within cortex - Soap bubbly/expansile - Metaphyseal in location typically

Answer 38

Non-ossifying fibroma (Non-ossifying = 3cm or larger, called Fibrous cortical defect if = 1-3cm or in children 4-8 y.o)

Question 39

What DDX are likely the cause of these findings?

Answer 39

- Giant cell tumor - Chondroblastoma - ABC (aneurysmal bone cyst) In kids = ICE (Infection, Chondroblastoma, Eosinophilic Granuloma)

Question 40

Features of ____ include: - Metaphyseal extending to epiphyseal - Soap bubbly w/ short zone of transition - Quasi-malignant

Answer 40

Giant cell tumor

Question 41

What condition is likely the cause of these findings?

Answer 41

Giant cell tumor

Question 42

What condition is likely the cause of these findings?

Answer 42

due to epiphyseal location

Question 43

What condition is likely the cause of these findings?

Answer 43

- DDX: Bone infarct vs. Enchondroma vs. low grade Chondrosarcoma Reccomend MRI to r/o chondrosarcoma

Question 44

Features of ___ include: - Necrosis in medullary compartment of metaphysis and/or diaphysis - Patchy intramedullary sclerosis w/ areas of radiolucency - Serpiginous calfication

Answer 44

Bone infarct DDX: Encondroma & Low grade chondrosarcoma

Question 45

Three main causes of regional osteoporosis =

Answer 45

Disuse Complex Regional Pain Syndrome Transient Regional Osteoporosis of hip/Regional Migratory Osteoporosis

Question 46

What condition is likely the cause of these findings?

Answer 46

- Vertical bands of sclerosis at distal femur & proximal tibia - DX: Osteopathic striata

Question 47

Osteopathia striata may be present with ____ & ____ where it is then referred to as Mixed Sclerosing Bone Dysplasia

Answer 47

Osteopoikilosis & Osteopetrosis

Question 48

Features of ___ include: - Vertically oriented bands of sclerosis extending from metaphysis to diaphysis

Answer 48

Osteopathia striata

Question 49

Erlenmeyer flask deformity is associated with what DDX

Answer 49

Osteopetrosis, Sickle Cell Anemia, Thalassemia