Soft Tissue Tumours, AVN and Osteochondritis

Question 1

second most common site for AVN

Answer 1

capitellum of the humerus

Question 2

describe decompression of the femoral head in AVN

Answer 2

drill holes into the femoral neck, and push into the abnormal sclerotic / granulomatous area

Question 3

what can happen at these sites - pre-patellar, olecranon and the 1st metatarsal?

Answer 3

inflamed bursa
may progress to bursitis
“bunion”

Question 4

causes of osteochondritis (3)

Answer 4

young active people - repeated traction / compression during sports
any age - due to FMH or coagulopathy

Question 5

what causes capillary compression in osteochondritis?

Answer 5

blood and oedema

Question 6

2 bones in the foot affected by osteochondritis
1 bone in the hand
1 part of the arm

Answer 6

foot - navicular and 2nd metatarsal head
hand - lunate carpal bone
arm - capitellum of the elbow

Question 7

most common benign soft tissue tumour?

where do they occur?

Answer 7

Lipoma

subcutaneous fat, and potentially muscle too

Question 8

Giant cell tumours of the tendon sheath are benign. What do they look like on histology?

Answer 8

brown due to haemosiderin

multinucleated

Question 9

what is Pigmented Villonodular Synovitis?

where do they commonly occur?

Answer 9

a giant cell tumour within a joint

commonly in the knee, causing effusion and pain. may be localised or diffuse

Question 10

what may weaken the joint capsule/ tendon sheath and predispose to a Ganglion cyst?

Answer 10

high pressure - arthritis / joint damage

developmental - juevenile Baker’s cyst