Week 3: Bone Diseases

Question 1

Joint effusion

Answer 1

Accumulation of fluid in the joint associated with an underlying condition
There are typical appearances of effusions in the ankle, knee, elbow and hip that aid in the diagnosis of subtle
pathologies

Question 2

Sail Sign

Answer 2

In the elbow. Anterior fat pad elevation looks like a
sail and is a sign of joint effusion and potential fracture

Question 3

Legge-Calve-Perthe’s Disease

Answer 3

Flattening of the femoral head due to
vascular interruption
Avascular necrosis of the capital femoral epiphysis of the femoral head
Most common in Caucasian males 4-8 years old

Question 4

Osgood schlatter’s

Answer 4

Incomplete separation or avulsion of the tibial tuberosity
A chronic fatigue injury due to repeated microtrauma at the patellar ligament insertion onto the tibial tuberosity, usually affecting boys between 10-15 years

Question 5

Osteopetrosis

Answer 5

Rare, hereditary bone dysplasia causes “marble bones”, severity varies
Normal resorptive calcium mechanism is absent, interferes with normal bone replacement
Prevents bone marrow from forming, patients can be anemic
Bones become brittle and stress fracture often
Technical factors (mAs, kV) must be increased to account for increased bone formation

Question 6

Osteogenesis imperfecta

Answer 6

Brittle bone disease an inherited generalized disorder of connective tissue
Characterized by fragile bones, bowed legs and an
unusual blue color of the normally white sclera of the
eye
Patients suffer repeated fractures

Question 7

Achondroplasia

Answer 7

Hereditary disorder
The most common form of dwarfism
Growth plates of the long bones don’t proliferate new growth properly, leading to a normal trunk length but abnormally short limbs, and large head

Question 8

Acromegaly

Answer 8

Excessive growth hormone AFTER bone growth has stopped
Often caused by a pituitary tumour
Sometimes follows gigantism (excessive
growth hormone BEFORE bone growth has stopped) if hypersecretion of growth hormone doesn’t cease at maturity

Question 9

Congenital (Developmental) Hip Dysplasia

Answer 9

Results from incomplete acetabulum formation caused by physiologic & mechanical factors
Femoral head pops out of joint during flexion and abduction

Question 10

Rheumatoid Arthritis

Answer 10

Chronic systemic disease of unknown cause
Appears primarily as a non-infectious inflammatory arthritis of the small joints of the hands and feet
Begins as an inflammation of the synovial membrane (synovitis) that lines the joints

Question 11

Bursitis

Answer 11

Inflammation of the bursae (small fluid filled sac within joint space to reduce friction)
Causes pain, frozen joints (immobility)

Question 11

Osteoarthritis

Answer 11

Degenerative condition
Loss of joint cartilage and reactive new bone formation
Usually affects the weight-bearing joints (spine, hip, knee and ankle) and the interphalangeal joints of the
fingers

Question 12

Osteomyelitis

Answer 12

An inflammation of the bone and bone marrow, caused by infectious organism
A soft tissue infection may spread from a skin abscess or decubitus ulcer (ex diabetic foot)

Question 13

Osteomyelitis Image Appearance

Answer 13

Imaging Appearance:
- Localized, deep soft tissue
swelling adjacent to the
metaphysis
- Metaphyseal lucency which
progresses to bone destruction
(ragged, moth-eaten
appearance)

Question 14

Osteoporosis

Answer 14

Generalized or localized
deficiency of bone density
Bone mass is decreased
Lack of calcium and vitamin D
Compression fractures common in spines;
fractured wrists and hips in elderly

Question 15

Osteopenia

Answer 15

Decreased mineral bone density
Can be from disease or disuse
Osteopenia can be risk factor for osteoporosis

Question 16

Osteomalacia

Answer 16

Loss of bone density due to nonmineralized osteoid
Caused by vitamin D deficiency
Makes bones soft

Question 17

Gout

Answer 17

A disorder in the metabolism of purine (a component of nucleic acids) in which an increase in the blood level of uric acid leads to the deposition of uric acid crystals in the joints, cartilage, and kidney. Urate crystals can be present in the joint spaces.

Question 17

Rickets

Answer 17

Pediatric disease of osteomalacia
Vitamin D deficiency
Imaging appearance
- Cupped and frayed metaphyseal ends of the bone
- Bowing of weight bearing bones

Question 18

Paget’s Disease
(osteitis
deformans)

Answer 18

A chronic metabolic bone disease; destruction of bone followed by a reparative process results in weakened, deformed, and thickened bone structures that tend to
fracture easily
Commonly affects the skull, long bones, pelvis and vertebra

Question 19

Ischemic Bone Necrosis

Answer 19

A condition that occurs when there is loss of blood to the bone; eventually without adequate blood supply, the bone dies.
Also known as avascular necrosis, osteonecrosis,
and aseptic necrosis
Most common site is the femoral head

Question 20

Osteochondritis Dissecans

Answer 20

The end result of an aseptic separation of bony or cartilaginous fragment
The piece can become a “loose body” in the joint
Thought to be from repetitive stress in young athletes
often in condyles of knees

Question 21

SNAT

Answer 21

Suspected Non-Accidental Trauma, battered child syndrome