BENIGN BONE TUMOURS

Question 1

Benign bone tumours

Answer 1

(which don’t metastasize) can be neoplastic, developmental, traumatic, infectious or inflammatory in nature.

Question 2

B- Most common tumour

Answer 2

osteochondroma

Question 3

B-What is a osteochondroma

• malignancy?
• growth? what do u do?
• lots?

- problems?

Answer 3

produces a bony outgrowth on the external surface with a cartilaginous cap.

Question 4

osteochondroma symptoms

Answer 4

no problems but can produce local pain.

Question 5

osteochondroma malignancy?

Answer 5

1% malignant transformation

Question 6

If it continues to grow?

Answer 6

growing in size or producing pain may require excisional biopsy.

Question 7

B- What is a enchondroma (5)

Answer 7

intramedullary and metaphyseal cartilaginous tumour caused by failure of normal enchondral ossification at the growth plate.

Question 8

enchondroma appearance

Answer 8

lesion is lucent but can undergo mineralization with a patchy sclerotic appearance.

Question 9

enchondroma symptoms

Answer 9

the lesions are usually asymptomatic but can weaken the bone resulting in pathologic fracture.

Question 10

enchondroma sites

Answer 10

femur, humerus, tibia and small bones of the hand and feet.

Question 11

enchondroma treatment

Answer 11

once a fracture has healed or if there is a risk of impending fracture they may be scraped out (curettage) and filled with bone graft to strengthen the bone

Question 12

B- What is a simple bone cyst

Answer 12

a single cavity benign fluid filled cyst in a bone

Question 13

simple bone sites sites

Answer 13

a growth defect from the physis and are therefore metaphyseal in long bones (usually in the proximal humerus and femur)

although they can occur in the talus or calcaneus.

Question 14

simple bone cyst symps & investigation

Answer 14

asymptomatic/ incidental finding on xray (usually a child or young adult) can cause weakness leading to pathological fracture.

Question 15

simple bone cyst treat

Answer 15

treatment with curettage and bone grafting with or without stabilization may be required

Question 16

B- What is an aneurysmal bone cyst

Answer 16

contains lots of chambers which are filled with blood or serum and different chambers may be seen on xray.
due to a small arteriovenous malformation.

Question 17

aneurysmal bone cyst sites

Answer 17

can occur in the metaphyses of many different long bones, flat bones (ribs, skull) and vertebral bodies

Question 18

aneurysmal bone cyst symps

Answer 18

lesion is locally aggressive causing cortical expansion and destruction and is usually painful

risk of pathological fracture.

Question 19

aneurysmal bone cyst treat

Answer 19

treatment is again with curettage and grafting or the use of bone cement.

Question 20

B-What is a giant cell tumour of bone + aetiology

Answer 20

locally aggressive and have a predilection for the metaphyseal region but tend to involve the epiphysis and can extend to the subchondral bone adjacent to the joint.

aetiology is unknown but as the name suggests histologically they consist of muli‐nucleate giant cells.

Question 21

giant cell tumour of bone sites

Answer 21

most commonly occur around the knee and in the distal radius but can occur in other long bones, the pelvis and the spine.

Question 22

giant cell tumour of bone symps

Answer 22

occur after the physis has fused and are locally destructive destroying cortex. They are painful and may cause pathological fracture.

Question 23

giant cell tumour of bone investigate

Answer 23

Xray they have a characteristic “soap bubble” appearance.

considered benign, 5% can metastasize to the lung with benign pulmonary GCT.

Question 24

giant cell tumour of bone treat

Answer 24

treatment is intralesional excision with use of phenol, bone cement or liquid nitrogen to destroy remaining tumour material and reduce the risk of recurrence.

very aggressive lesions with cortical destruction may need joint replacement

Question 25

B-What is Fibrous dysplasia

Answer 25

disease of a bone occurring in adolescence where a genetic mutation results in lesions of fibrous tissue and immature bone.

can affect one bone (monostotic) or more (polyostotic).

Question 26

sites fibrous dysplasia

Answer 26

head & neck

Question 27

signs fibrous dysplasia

Answer 27

defective mineralization may result in angular deformities and the affected bone is wider with thinned cortices.

stress fractures can occur and extensive involvement of the proximal femur can produce a shepherd’s crook deformity

Question 28

investigate fibrous dysplasia

Answer 28

bone scans show intense increase in uptake during development but the lesion usually becomes inactive.

Question 29

fibrous dysplasia treat

Answer 29

bisphosphonates may reduce pain and pathologic fractures should be stabilized with internal fixation and cortical bone grafts used to improve strength.

Simple intralesional excision alone has a very high recurrence rate

Question 30

B-what is a osteoid osteoma (6)

Answer 30

small nidus of immature bone surrounded by an intense sclerotic halo

Question 31

osteoid osteoma sites

Answer 31

commonly occur in adolescence and common sites include the proximal femur, the diaphysis of long bones and the vertebrae.

Question 32

osteoid osteoma symps

Answer 32

clinical feature is intense constant pain, worse at night due to the intense inflammatory response.

pain is greatly relieved by NSAIDs.

Question 33

osteoid osteoma investigate

Answer 33

lesion may be seen on xray however bone scan (intense local uptake) and CT can confirm the diagnosis

Question 34

osteoid osteoma treat

Answer 34

lesion may resolve spontaneously over time but some cases may require CT guided radiofrequency ablation or en bloc excision.

Question 35

B-What is a brodies abcess

Answer 35

Brodie’s abscess (subacute osteomyelitis) and hyperparathyroidism (Brown tumours) can also present with a lytic lesion of bone.