Pathology

Question 1

Osteochondroma

Answer 1

Bony outgrowth with cartilage cap, pain

Benign

Question 2

Enchondroma

Answer 2

Intramedullary cartilage tumour
Lucent or patchy sclerotic
Pathologic fracture, benign

Question 3

Simple bone cyst

Answer 3

Single fluid filled cavity, metaphysis

Asymp or weakness

Question 4

Aneurysmal bone cyst

Answer 4

Many chambers with blood or serum
Due to arteriovenous malformation
Benign but locally aggressive = cortical expansion and destruction = pain and pathologic fracture

Question 5

Giant cell tumour

Answer 5

Knee and distal radius
Benign but locally aggressive = pain and pathologic fracture
Multinucleate giant cells, soap bubble appearance
Can spread to lung

Question 6

Fibrous dysplasia

Answer 6

Fibrous tissue and immature bone in adolescents
Angual deformities, wide thin cortex, stress fractures
Shepherd’s crook deformity - proximal femur

Question 7

Osteoid osteoma

Answer 7

Immature bone surrounded by sclerotic halo

Intense constant pain worse at night = NSAIDs

Question 8

Brodie’s abscess

Answer 8

Subacute osteomyelitis

Lytic lesion of bone

Question 9

Brown’s tumour

Answer 9

Hyperparathyroidism

Lytic lesion of bone

Question 10

Osteosarcoma

Answer 10

Primary malignant bone tumour
Young, knee
Pulmonary mets

Question 11

Chrondrosarcoma

Answer 11

Cartilage producing primary bone tumour
Middle aged
Large, pelvis, proximal femur
Don’t respond to chemo/radio

Question 12

Fibrosarcoma

Answer 12

Fibrous malignant primary bone tumour in abnormal bone (Paget’s, fibrous dysplasia)
Young adults

Question 13

Ewing’s sarcoma

Answer 13

Malignant tumour of bone marrow
10-20 years, poor prognosis
Fever, warm swelling, raised inflammatory markers
Radio/chemo

Question 14

Lymphoma

Answer 14

Cancer of lymphatics
Primary bone tumour: non-Hodgkins, or mets to bone
Lymphadenopathy, splenomegaly

Question 15

Myeloma

Answer 15

Malignant B cell prolfieration
Multiple osteolytic lesions (MM)
45-65 years
Weakness, back pain, fatigue, anaemia, infections

Question 16

Diagnosis of myeloma

Answer 16

Plasmapheresis - high paraprotein

Early mornine urine - BJP

Question 17

Tumours with common bone mets

Answer 17

Breast
Prostate
Lung
RCC
Thyroid
Colon
Bladder

Question 18

Lipoma

Answer 18

Benign soft tissue tumour

Subcutaneous fat

Question 19

Giant cell tumour of tendon sheath

Answer 19

Small firm swelling on flexor tendon sheath of finger
Pain, can erode bone
Multinucleated giant cells and haemosiderin

Question 20

PVNS

Answer 20

Pigmented Villonodular Synovitis

Pain and effusions in synovial joint

Question 21

What is a sarcoma?

Answer 21

Malignant soft tissue tumour

Question 22

Ganglion cyst

Answer 22

Around synovial joint/synovial tendon sheath
Herniation due to damage or development
Well defined, firm, transilluminate

Question 23

Bursitis

Answer 23

Inflammation of fluid filled sac due to repeated pressure or trauma

Question 24

Sebaceous cyst

Answer 24

Dermoids

Question 25

Abscess

Answer 25

Infected sebaceous cyst/cellulitis/bursitis

Question 26

Osteochondritis

Answer 26

Inflamed cartilage or bone in kids/young adults - repetitive stress (traction or compression) Bleeding, oedema, compression Pain, arthritis 2nd MT head, navicular, lunate, capitulum

Question 27

Osteochondritis dissecans

Answer 27

Fragmentation of cartilage/bone | Pain, effusion, locking, giving way

Question 28

Perthes disease

Answer 28

Transient AVN of femoral head | Pre-pubertal small active boys

Question 29

Sites prone to AVN

Answer 29

Femoral head, Humeral head, scaphoid, talus Patchy sclerosis, collapse Secondary OA

Question 30

Causes of AVN

Answer 30

Idiopathic, fractures, steroids, alcohol, hyperlipidaemia, stasis, APS, SLE