Abstract
Orthopaedic Oncology Structured SBA Questions
Orthopaedic Oncology Structured SBA Questions
1. A 52-year-old female presents with a 2-year history of sternal pain with associated diffuse rib pain and generalised muscle weakness. X-rays demonstrate widespread osteopaenia with multiple old rib fractures and a recent Dotatate scan revealed an area of increased uptake within the sternum. Further investigations demonstrated raised FGF23 levels and high urinary phosphate.
What is the most likely diagnosis?
2. A 10-year-old female presents with an enlarging painless mass in the left buttock extending over the greater trochanter, resulting in some restriction of hip movement. The overlying skin is tense and at risk of ulceration. Investigations demonstrate hyperphosphataemia and a periarticular well-circumscribed cystic mass with fluid–fluid levels suggestive of a sedimentation sign.
What is the most likely diagnosis?
3. A 14-year-old male presents to the ED after sustaining an ankle injury playing football. X-rays performed demonstrate a Weber A fracture of the lateral malleolus. Note is made of a well-defined lesion with a geographic margin based in the anterior cortex of the tibial diaphysis with thinning of the cortex and associated sclerosis. There is no evidence of periosteal reaction and the patient denies any symptoms in the area.
What is the most appropriate management?
4. Radiographs of a young boy demonstrate an exophytic lesion arising from the cortical surface of the proximal phalanx of his left ring finger. There does not appear to be continuity with the medullary cavity. The lesion is excised, as it is causing impingement to flexion at the PIPJ. Histology demonstrates a ‘bizarre’ proliferation of bone, cartilage and fibrous tissue.
Which of the following is the most likely diagnosis?
5. Bone tumours are often associated with classical appearances on radiological investigation and are commonly located in specific anatomical locations.
Which of the following statements is incorrect?
6. Which of the following statements about osteochondromas is true?
7. The following statements regarding cartilaginous tumours are all true except which?
An enchondroma is a benign cartilage tumour that occurs only in bones which develop from endochondral ossification
Enchondromas typically do not increase in size after skeletal maturity; however, growth or pain raises suspicion of malignant transformation
In the setting of multiple lesions, malignant transformation is less frequent than in osteochondromatosis (hereditary multiple exostoses)
8. A 7-year-old girl presents to ED after a minor fall on the playground at school. Radiographs demonstrate a large lytic lesion in the proximal humerus with an associated pathological fracture which is minimally displaced. The lesion has a geographic margin, no periosteal reaction and a ‘fallen leaf’ fragment in it.
What is the most appropriate next step?
9. A 12-year-old boy presents to ED with a short history of a swelling in the left shoulder. He sustained an injury playing rugby a few weeks beforehand; however, because of increasing swelling and pain he attended for an x-ray. This demonstrated an eccentric metaphyseal expansile lytic lesion in the proximal humerus with cortical erosion. CT and MRI confirmed fluid–fluid levels and no evidence of soft tissue mass or periosteal reaction.
What is the likely diagnosis?
10. A 17-year-old male presents with a 6-month history of pain in the right proximal thigh. He denies any significant trauma. He complains of night pain and denies any other systemic symptoms. He finds anti-inflammatory medication very helpful in relieving pain.
The following statements are all true except which?
11. A 13-year-old male presents with a history of acute onset right thigh pain following a short prodromal fever. He has a mildly elevated ESR and his remaining laboratory results are normal. X-rays demonstrate a lesion in the mid-diaphysis of the femur, and MRI confirms no evidence of any soft tissue component. Biopsy demonstrates a histiocyte rich lesion.
Which of the following statements is true?
12. A 30-year-old female physiotherapist presents with right wrist pain and swelling with no history of trauma. X-ray demonstrates an eccentric, lytic lesion in the distal radius (Figure 23.1), and MRI demonstrates a breach in the cortex with a small soft tissue component. Biopsy reveals a tumour comprising multinucleated giant cells and stromal cells.
Figure 23.1 AP radiograph wrist
The following statements are all true except which?
13. A 20-year-old male presents with a 3-month history of progressive right knee pain, swelling and restricted movement. X-ray demonstrates a small radiolucent epiphyseal lesion within the tibial plateau with no cortical involvement and MRI confirms extensive surrounding oedema with no soft tissue component. Biopsy demonstrated hyaline cartilage with ‘chicken-wire calcification’.
What is the most likely diagnosis?
14. A 50-year-old male presents following a fall from scaffolding with injuries to his left arm and left knee. Radiographs demonstrate a pathological fracture of the midshaft of the humerus through a well-defined radiolucent area. X-rays of the femur and tibia also demonstrate expansile radiolucent lesions with a thin sclerotic rim and a ground-glass matrix. He has a previous history of two benign soft tissue excisions from his left buttock and medial thigh.
What is the most likely diagnosis?
15. A 60-year-old female presents with a 10-year history of an enlarging painless mass in the right thigh. An MRI scan demonstrates a 10cm x 5cm well-encapsulated homogenous lesion superficial to the adductor compartment with post-contrast fat-saturated T1 imaging confirming complete suppression of fat signal intensity within the mass.
All of the following statements are true except which?
Lesions deep to the fascia with thick septations and heterogeneity raise the possibility of a sarcoma
16. A 30-year-old female presents with a recurrent painful mass in the left infraclavicular fossa. She also complains of intermittent paraesthesia in the left arm with some mild weakness. The mass lies deep to a surgical scar from a previous excision of a benign fibrous lesion. She has a history of familial adenomatous polyposis. Biopsy showed bland fibroblasts and myofibroblasts.
All of the following statements are true except which?
17. A 28-year-old male presents with pain and swelling in the left knee. He describes recurrent episodes of swelling following minor trauma and has previously had aspiration of the joint in the ED in which blood-stained fluid was removed. A recent MRI demonstrates diffuse synovitic changes with a mass in the intercondylar notch, low signal on T1 because of haemosiderin deposition and early destructive changes in the articular cartilage.
What is the most likely diagnosis?
18. A 40-year-old male presents with a painful mass in the thigh. It is particularly painful if knocked. He complains of intermittent tingling and a shooting pain into the foot. MRI demonstrates a mass of low T1 signal and high T2 with diffuse enhancement with gadolinium and a ‘sweet potato’ sign (Figure 23.2 shows coronal T2 sequence).
Figure 23.2 MRI coronal T2 sequence
All of the following statements are true except which?
19. A 56-year-old female with neurofibromatosis type 1 is referred with an enlarging painful mass in her right thigh. Recent PET scan has demonstrated increased avidity with a rise in the SUV of the lesion compared with previous imaging.
All of the following statements are true except which?
A change in symptoms or imaging characteristics of a long-standing neurofibroma requires urgent investigation and biopsy
Neurofibromas are composed of Schwann cells, making them difficult to distinguish from schwannomas
Solitary neurofibromas are usually benign lesions; however, malignant transformation can occur in patients with neurofibromatosis
20. A 40-year-old male presents with a 5-year history of pain and swelling in the left knee, which is worse with activity. He complains of intermittent stiffness and locking and is no longer able to cycle. A radiograph of the knee demonstrates multiple small, loose bodies with a well-preserved joint space.
What is the most likely diagnosis?
21. A 50-year-old male presents with a painful lesion on the medial plantar aspect of his right foot. He has been aware of the lesion for some years; however, it is now exquisitely painful. Imaging has demonstrated a superficial, small <1cm lesion closely related to a vein.
What is the most likely diagnosis?
22. Bisphosphonates can be used as part of the treatment of all the following conditions except which?
23. Non-ossifying fibroma is a benign fibrogenic lesion that can be associated with all of the following conditions except which?
24. A 63-year-old male presents with progressive stiffness in the right elbow and an associated mechanical block to ROM. He was involved in a road traffic accident 6 months ago, where he sustained a skull fracture and intracerebral haemorrhage. He has a resolving right-sided hemiplegia. Plain radiographs show well-defined calcification in the soft tissues.
All of the following statements are true except which?
Associated findings may include soft tissue contractures, nerve impingement and chronic regional pain syndrome
25. A 20-year-old male presents with a firm mass in the anterior compartment of the thigh. He sustained an injury to the area approximately 6 months ago during a rugby tackle. The bruising has since resolved. X-ray, CT and MRI have demonstrated a lesion within the rectus femoris for which a biopsy has been performed. The tissue demonstrated an irregular mass of immature fibroblasts surrounded by trabeculae of lamellar and woven bone.
What is the most likely diagnosis?
27. A 40-year-old male presents with worsening pain around his left knee. He was told as a child that he had a bony growth arising from the distal femur which was benign and required no treatment. He has recently been training for a triathlon and has noticed that the swelling has increased. X-ray demonstrates a pedunculated lesion arising from the posterolateral aspect of the distal femur in continuity with the medullary cavity.
What would the next most appropriate step in his management be?
28. A 30-year-old male presents with a 3-year history of left knee pain. Radiographs demonstrate an eccentric lytic lesion within the metaphysis, which on MRI demonstrates low signal on T1- and high signal on T2-weighted images. Biopsy shows variable amounts of chondroid, fibromatoid and myxoid tissue with stellate cells.
What is the most likely diagnosis?
29. All of the following conditions have the potential to undergo malignant transformation and/or metastasise except which?
30. A 50-year-old female presents with a 6-month history of right knee pain. Radiographs demonstrate a well-defined lytic lesion in the proximal tibia with a sclerotic rim and no periosteal reaction. She is frustrated that she has been in pain for 6 months.
What is the next most appropriate step in her management?
31. A 6-year-old otherwise healthy boy presents with a year’s history of pain in the mid shin. The pain wakes him up at night but responds to anti-inflammatory medication. Examination is unremarkable. Plain radiograph shows an area of thickened cortex in the mid diaphysis of the tibia.
Which investigation is most likely to confirm the diagnosis?
32. Poor prognostic factors of osteosarcoma include all the following except which?
