Musculoskeletal and trauma

Question 1

1. A 17 year old girl presents with pain in the distal forearm which has worsened over
   the last six to eight weeks. Plain films show an eccentric lytic radiolucency in the distal
   radius with a soap-bubble appearance. The most likely pathology is:
   a. Enchondroma
   b. Aneurysmal bone cyst
   c. Simple bone cyst
   d. Fibrous dysplasia
   e. Chondroblastoma

Answer 1

1. b. Aneurysmal bone cyst
   Aneurysmal bone cyst is most common in females and 75% occur under 20 years of age.
   The classic presentation is of pain of relatively acute onset with a rapid increase in severity
   over 6–12 weeks. Common locations include the spine, with a slight preponderance for the
   posterior elements, and the metaphysis of long bones – femur, tibia, humerus and fibula.
   The lesion is usually expansile with thin internal trabeculations giving it the characteristic
   soap-bubble appearance.

Question 2

2. A 35 year old man presents with increasing stiffness in his knee and soft-tissue swelling
   around the joint. Plain films show multiple areas of irregular cyst-like radiolucencies
   in the distal femur. There are no areas of abnormal calcification and there is no evidence
   of periarticular osteoporosis. MR shows a low signal joint effusion on both T1 and T2
   sequences. The most likely diagnosis is:
   a. Synovial osteochondromatosis
   b. Pigmented villonodular synovitis
   c. Osteoarthritis
   d. Reiter’s syndrome
   e. Osteomyelitis

Answer 2

2. b. Pigmented villonodular synovitis
   Pigmented villonodular synovitis is a relatively rare condition which usually presents in the
   third or fourth decade. It is a monoarticular, painful disease which causes a decreased range
   of movement at the affected joint. It is most common at the knee (80%) followed by the hip,
   ankle, shoulder and elbow. Haemorrhagic ‘chocolate’ effusion is characteristic. Low signal
   effusion on all sequences at MR is characteristic. There is no calcification or osteoporosis,
   and joint space narrowing is a late feature.

Question 3

3. A 56 year old motorcyclist has a trauma series of plain films following a road traffic
   accident. On evaluation of the lateral cervical spine film, which of the following softtissue
   parameters would be a concerning feature?
   a. Predental space of 3mm
   b. Nasopharyngeal space of 7mm
   c. Retropharyngeal space of 10mm
   d. Retrotracheal space of 20mm
   e. Decreased disc space at the C5/6 level

Answer 3

3. c. Retropharyngeal space of 10mm
   This is too wide for the retropharyngeal space. The correct acceptable limits for soft-tissue
   measurements are as follows:
   Predental space 3mm in adults, 5mm in children.
   Nasopharyngeal space (anterior to C1) 10 mm.
   Retropharyngeal space (C2–C4) 5–7 mm.
   Retrotracheal space (C5–C7) 22 mm.
   Disc spaces should be roughly equal throughout the cervical spine. Narrowing of a disc
   space is usually due to degenerative change, but widening would be a more concerning
   feature.

Question 4

4. A 20 year old man presents with an increasingly painful right thigh which is worse at
   night. Plain films of the area show a lucent area measuring approximately 8–9mm in
   the distal femur surrounded by extensive sclerosis. The most likely diagnosis is:
   a. Osteoblastoma
   b. Giant cell tumour
   c. Brodie’s abscess
   d. Osteoid osteoma
   e. Chondroblastoma

Answer 4

4. d. Osteoid osteoma
   This most commonly presents in the second and third decades. The male:female ratio is
   2.5:1. Classically it presents with increasing pain which is worse at night and often relieved
   with aspirin. Spinal lesions often lead to painful scoliosis. Almost any site in the body may
   be affected but the most common regions are the lower limb and spine.

Question 5

5. In a 65 year old woman with a fracture of the neck of the humerus, which of the
   following classification systems to describe the fracture would be useful in guiding the
   surgical management?
   a. Garden classification
   b. Neer classification
   c. Weber classification
   d. Fryman system
   e. Crosby–Fitzgibbon system

Answer 5

5. b. Neer classification
   The Neer classification system is used to grade humeral neck fractures. This system
   describes four parts – greater tuberosity, lesser tuberosity, humeral head and shaft of
   humerus. According to Neer, a fracture is displaced if there is more than 1 cm of displacement
   and 45 angulation between any two segments. Two-part fractures involve any of the
   four parts and include one fragment that is displaced. Three-part fractures include a
   displaced fracture of the surgical neck in addition to either a displaced greater tuberosity
   or lesser tuberosity fracture. Four-part fractures include displaced fractures of the surgical
   neck and both tuberosities.

Question 6

6. A 60 year old woman presents to her GP with renal colic and hypercalcaemia. She has
   the following findings on plain film: subperiosteal bone resorption of the proximal
   phalanges of the hands, chondrocalcinosis of the articular cartilage at the knee joints,
   and a well-defined lytic lesion in the body of the mandible. The most likely unifying
   diagnosis is:
   a. Parathyroid adenoma
   b. Parathyroid carcinoma
   c. Renal osteodystrophy
   d. Osteomalacia
   e. Myeloma

Answer 6

6. a. Parathyroid adenoma
   Parathyroid adenoma would be the most likely cause of primary hyperparathyroidism.
   Parathyroid carcinoma would produce a similar radiographic picture but is much less
   common. Brown tumours are seen in both primary and secondary hyperparathyroidism
   and are most common in the mandible, ribs and pelvis; they have a variable appearance on
   MRI and may simulate primary or secondary neoplasms

Question 7

7. In a 21 year old man with symptoms of chronic back pain, pain in his feet, particularly
   the great toe and metatarsophalangeal joints, and bilateral sacroiliitis on plain films, the
   most likely diagnosis is:
   a. Ankylosing spondylitis
   b. Gout
   c. Inflammatory bowel disease-related arthropathy
   d. Reiter’s syndrome
   e. Psoriatic arthritis

Answer 7

7. d. Reiter’s syndrome
   Reiter’s syndrome is the association of urethritis, conjunctivitis and mucocutaneous
   lesions. Sacroiliitis is usually bilateral but often persists asymmetrically. There is an
   association with the HLA B27 antigen. Reiter’s has a predeliction for the great toe and
   metatarsophalangeal joints.

Question 8

8. A 45 year old woman falls onto her outstretched hand. The following findings on PA
   and lateral wrist plain films indicate which pathology? A scapholunate angle of 70,
   a capitolunate angle of less than 20, and a 4mm gap between scaphoid and lunate
   on PA view.
   a. Normal appearances
   b. Scapholunate dissociation
   c. Volar intercalated segment instability (VISI)
   d. Dorsal intercalated segment instability (DISI)
   e. Perilunate dislocation

Answer 8

8. b. Scapholunate dissociation
   In scapholunate dissociation the scapholunate angle is >60 and there is a >3mm gap
   between the scaphoid and lunate on AP view of the wrist. In VISI, capitolunate angle is
   increased and there is volar angulation of the lunate. In DISI, both scapholunate and
   capitolunate angles are increased and there is dorsal angulation of the lunate.

Question 9

9. A young man presents to A&E following a fall onto his outstretched right arm. Plain
   films of the right forearm show a fracture of the distal forearm with volar angulation
   of the distal fragment with no intra-articular component. The carpal bones remain
   well aligned. Which of the following injuries has he sustained?
   a. Smith’s fracture
   b. Barton’s fracture
   c. Monteggia fracture
   d. Galeazzi fracture
   e. Colles fracture

Answer 9

9. a. Smith’s fracture
   This description is of a Smith’s fracture. More common is a Colles fracture, which is
   a fracture of the distal radius with dorsal angulation of the distal fragment. A Monteggia
   fracture is fracture of the ulnar with dislocation of the radial head. A Galeazzi fracture is
   a fracture of the radius with dislocation of the distal ulnar. Barton’s fracture is a fracture of
   the distal radius with dislocation of the distal radiocarpal joint

Question 10

10. A 24 year old man injured his left knee whilst skiing. He presents with pain and
    swelling over the lateral aspect of the knee joint. AP plain radiographs demonstrate an
    avulsion fracture of the lateral aspect of the proximal tibia below the articular surface.
    A joint effusion is also seen. The most likely associated ligamentous injury is to which
    of the following structures?
    a. Posterior cruciate ligament
    b. Anterior cruciate ligament
    c. Medial collateral ligament
    d. Lateral collateral ligament
    e. Ligament of Humphry

Answer 10

10. b. Anterior cruciate ligament
    The fracture described is a Segond fracture, originally documented by Dr Paul Segond in
    1879 after a series of cadaveric experiments. The Segond fracture occurs most commonly
    in association with anterior cruciate ligament injuries (75–100%) and medial meniscal
    injuries. Due to the high rate of associated injuries, a patient who sustains a Segond fracture will require further imaging, usually by way of MRI, in order to specifically investigate the
    ligaments and menisci.

Question 11

11. A 22 year old man presents to his GP with pain in his right knee which is gradually
    worsening in severity and is relatively resistant to analgesia. MRI of the knee demonstrates
    an area of geographic bone destruction in the distal femur with a wide zone of
    transition. There is marked aneurysmal dilatation of the bone and a fluid-fluid level is
    present within the lesion. The most likely diagnosis is:
    a. Plasmacytoma
    b. Simple bone cyst
    c. Giant cell tumour
    d. Telangiectatic osteosarcoma
    e. Parosteal osteosarcoma

Answer 11

11. d. Telangiectatic osteosarcoma
    With the MRI finding described, the most likely explanation is that the lesion is a
    telangiectatic osteosarcoma. This is a rare type of osteosarcoma with a mean age at
    presentation of 20 years. The most common site is around the knee (62%). Fluid-fluid
    levels are also seen in giant cell tumours and aneurysmal bone cysts.

Question 12

12. A 32 year old footballer sustains an avulsion injury to the anterior superior iliac spine
    during training. Which of the following muscles is likely to be affected?
    a. Sartorius
    b. Gracilis
    c. Iliopsoas
    d. Rectus femoris
    e. Semimembranosus

Answer 12

12. a. Sartorius
    Sartorius has its origin at the anterior superior iliac spine and inserts into the pes anserinus.
    A sartorius muscle injury can therefore cause an avulsion fracture of the anterior superior
    iliac spine. Gracilis has its origin at the inferior pubic ramus, and rectus femoris has its
    origin at the anterior inferior iliac spine

Question 13

13. A middle-aged woman undergoes an MRI of the lumbar spine for longstanding lower
    back pain. She has no specific neurological signs and is otherwise well. MRI shows
    some lower lumbar spine facet joint arthropathy and a 22 cm well-defined rounded
    lesion in the L3 vertebral body. This displays high signal on both the T1 and T2
    sequences. The most likely explanation for this lesion is:
    a. Discitis
    b. Lymphoma
    c. Myeloma
    d. Metastatic deposit
    e. Haemangioma

Answer 13

13. e. Haemangioma
    This is most likely to be a benign haemangioma. These are relatively common lesions seen as
    incidental findings on spinal imaging. High signal on T1 imaging is indicative of the presence
    of fat within the lesion. All the other conditions would give a low-signal lesion on T1 imaging.

Question 14

14. A 21 year old long-distance runner complains of increasing right groin pain.
    Plain films show no acute bony injury, but demonstrate a pistol grip deformity
    of the femoral head, an osseous bump deforming the femoral head–neck junction
    and an alpha angle of 70. The acetabulum appears normal. The most likely
    diagnosis is:
    a. Hip dysplasia
    b. Pincer-type acetabular impingement
    c. Cam-type acetabular impingement
    d. Sportsman’s hernia
    e. Avascular necrosis

Answer 14

14. c. Cam-type acetabular impingement
    Femoroacetabular impingement (FAI) occurs as a result of repetitive microtrauma due to
    an anatomic conflict between the proximal femur and the acetabular rim at the extremes of
    motion. An osseous bump at the femoral head–neck junction is present in 50% of cam-type
    FAI and only 33% of pincer-type FAI. An alpha angle of >55 is indicative of cam-type FAI.
    The alpha angle, drawn on the AP pelvis radiograph, is formed by a line drawn from
    the centre of the femoral head through the centre of the femoral neck, and a line from the
    centre of the femoral head to the femoral head–neck junction, found by the point by which
    the femoral neck diverges from a circle drawn around the femoral head. A normal patient’s
    alpha angle is around 45, whereas for patients with FAI it may be around 70.

Question 15

15. A 24 year old rugby player attends A&E following a tackle during which he felt his left
    shoulder dislocate. Initial plain radiographs confirm an anterior inferior dislocation
    of the left shoulder. Which of the following statements is true?
    a. The humeral head lies inferior and lateral to the glenoid on the AP view
    b. The presence of a Hill–Sachs defect indicates previous dislocation
    c. Hill–Sachs lesions are more common than Bankart lesions
    d. Anterior dislocation accounts for 50% of shoulder dislocations
    e. A Hill–Sachs lesion affects the inferior aspect of the humeral head

Answer 15

15. c. Hill–Sachs lesions are more common than Bankart lesions
    A Hill–Sachs lesion affects the postero-superior aspect of the humeral head and whilst it
    does often indicate a previous dislocation, this is not necessarily the case and it can be
    present after a single episode. A Bankart lesion affects the inferior glenoid. Almost 95% of
    all shoulder dislocations are anterior.

Question 16

16. In a 26 year old woman with sickle cell disease, which one of the following would not
    be considered a typical musculoskeletal manifestation of the disease?
    a. Osteopaenia and trabecular thinning
    b. ‘Bone within bone’ appearance
    c. Avascular necrosis of the femoral head
    d. Posterior vertebral scalloping
    e. Fish deformity of the vertebrae

Answer 16

16. d. Posterior vertebral scalloping
    Posterior vertebral scalloping is not a feature. The remainder are all classic features of sickle
    cell anaemia, along with ‘hair-on-end’ appearance of the skull due to coarse granular osteoporosis and widening of the diploe. Osteomyelitis is a feature and is due to salmonella in over 50% of cases.

Question 17

17. A 74 year old woman presents with back pain and no history of recent trauma.
    Lateral plain radiographs show partial collapse of the L2 vertebral body. Which of
    the following findings would be more suggestive of osteoporotic collapse than
    malignancy?
    a. Complete replacement of the normal marrow signal within the vertebral body
    on T1 imaging
    b. Bilateral pedicular involvement with expansion of the right pedicle
    c. Bulging and convex appearance to the vertebral body
    d. Nodular irregular epidural mass
    e. Intervertebral vacuum phenomenon

Answer 17

17. e. Intervertebral vacuum phenomenon
    Intervertebral vacuum phenomenon is highly specific for osteoporotic collapse, although it
    is not common. The other features are all more suggestive of malignancy than osteoporotic
    collapse. Pedicular destruction occurs in 50% of cases of malignant collapse but in less than
    1% of osteoporotic collapse.

Question 18

18. A 23 year old man sustains a Jefferson fracture to his cervical spine following an injury
    in which he dived into a shallow swimming pool, hitting his head on the bottom.
    Which of the following regarding his injury is incorrect?
    a. Displacement of the lateral masses of C1 relative to the dens on an odontoid view
    indicates a transverse ligament rupture
    b. Associated C2 fracture will be present in up to 30% of cases
    c. Jefferson fractures are usually associated with a neurological deficit
    d. Up to 50% are associated with a further cervical spine injury
    e. There may be associated vertebral artery injury

Answer 18

18. c. Jefferson fractures are usually associated with a neurological deficit
    Jefferson fractures are not usually associated with neurological deficit. Although there may
    be retropulsion of fragments into the vertebral canal, spinal cord injury is rare due to the
    large dimensions of the canal at this level. Vertebral artery injury, however, must be
    considered and if there is concern either CTA or MRA imaging should be considered.

Question 19

19. A 50 year old woman presents with a mass on the plantar aspect of her right foot.
    Ultrasound reveals a small oval-shaped lesion between the plantar portions of the
    metatarsal heads. MRI characteristics of the lesion are low-to-intermediate signal
    on T1 and low signal intensity on T2. Which of the following is the most likely
    diagnosis?
    a. Lipoma
    b. Morton’s neuroma
    c. Plantar fibromatosis
    d. Giant cell tumour of the tendon sheath
    e. Ganglion cyst

Answer 19

19. b. Morton’s neuroma
    The description is that of a Morton’s neuroma. This occurs most commonly in the third
    metatarsal space and less commonly in the second space. There is often an associated
    metatarsal bursitis which is a high signal on STIR imaging. Ultrasound is usually the first
    imaging modality; squeezing the metatarsal heads together during scanning will usually
    make the lesion more prominent.

Question 20

20. Following a traumatic left elbow fracture, a young man complains of paraesthesia in
    his left ring and little fingers. He also starts to notice weakness of his left hand.
    A diagnosis of ulnar nerve entrapment is made. Which of the following muscles will
    not be affected?
    a. Abductor digiti minimi
    b. Abductor pollicis brevis
    c. Adductor pollicis
    d. Flexor carpi ulnaris
    e. Flexor digiti minimi

Answer 20

20. b. Abductor pollicis brevis
    Abductor pollicis brevis is supplied by the median nerve and would therefore not be affected
    in an ulnar nerve injury. Due to the anatomic location of the ulnar nerve at the elbow, it can
    often be damaged leading to denervation and paralysis of the muscles supplied by the nerve.
    This includes the intrinsic muscles of the hand, which can be very debilitating. Injury to the
    ulnar nerve at the wrist would lead to severe muscle denervation sparing only the opponens
    pollicis, the superficial head of the flexor pollicis brevis and the lateral two lumbricals

Question 21

21. A routine pre-operative chest X-ray in a 62 year old woman shows bilateral erosion of
    the distal clavicles. Which one of the following conditions might be responsible?
    a. Hypoparathyroidism
    b. Rheumatoid arthritis
    c. Langerhans’ cell histiocytosis
    d. Ankylosing spondylitis
    e. Sarcoidosis

Answer 21

21. b. Rheumatoid arthritis
    Myeloma, hyperparathyroidism, metastases, cleidocranial dysplasia and Gorlin basal cell
    nevus syndrome all cause absence of the outer end of the clavicle. Destruction of the medial
    end of the clavicle is caused by metastases, infection, lymphoma, eosinophilic granuloma,
    rheumatoid arthritis and sarc

Question 22

22. A 74 year old woman with back pain presents to her GP. Initial plain radiographs of
    her spine show multiple sclerotic metastatic lesions. The most likely primary tumour
    would be:
    a. Renal cell carcinoma
    b. Melanoma
    c. Bronchial carcinoid
    d. Bladder
    e. Colorectal carcinoma

Answer 22

22. c. Bronchial carcinoid
    The most likely from the above list is a bronchial carcinoid. In men the most likely cause
    would be prostate. All the other conditions are more likely to produce lytic metastases
    than sclerotic.

Question 23

23. An elderly gentleman complaining of generalised aching in his lower limbs is shown to
    have bilateral distal tibial periostitis. There is no underlying bone lesion identified.
    Which of the following would be the most likely explanation?
    a. Arterial insufficiency
    b. Thyroid acropachy
    c. Trauma
    d. Pachydermoperiostosis
    e. Hypertrophic pulmonary osteoarthropathy

Answer 23

23. e. Hypertrophic pulmonary osteoarthropathy
    The most likely explanation is hypertrophic osteoarthropathy. Thyroid acropachy changes
    usually occur in the upper limb. Venous stasis is a cause of periostitis rather than arterial
    insufficiency. Trauma would be unlikely to be bilateral unless there was a specific history.
    Pachydermoperiostitis is the idiopathic form of hypertrophic osteoarthropathy, it usually
    presents around adolescence and is usually associated with clubbing.

Question 24

24. A 28 year old man is brought into the emergency department following an assault during
    which he was stabbed in the left flank. He has a 1.3 cm wound just below the left costal
    margin in the mid-axillary line. No information regarding the knife has been obtained.
    His renal function is within normal limits and he has no contrast allergies. The optimal CT
    protocol for scanning his abdomen would include the following contrast:
    a. IV contrast only
    b. Oral contrast and rectal contrast
    c. IV contrast and oral contrast
    d. Oral, rectal and IV contrast
    e. IV contrast and rectal contrast

Answer 24

24. d. Oral, rectal and IV contrast
    A triple contrast technique has been advocated in penetrating trauma where there may be
    concern regarding small bowel or colon trauma. If no oral or rectal contrast are given then
    a small bowel or colon injury can easily be missed.

Question 25

25. A 75 year old man who is on warfarin for atrial fibrillation is involved in a high-speed road traffic accident in which he sustains a head injury. He lost consciousness at the scene. On arrival at the A&E department his GCS is 15. He has no other obvious injuries. According to NICE guidelines, his management should include the following: a. Skull radiograph b. No immediate imaging but admission for regular neurological observations c. CT head d. Skull radiograph followed by CT head e. MRI head

Answer 25

25. c. CT head According to NICE guidance he should undergo CT head and the investigation should be performed within the hour following referral. The fact he is anticoagulated, over 65 and experienced a loss of consciousness would all be factors in warranting an urgent CT head.

Question 26

26. A young man with limited range of movement at the shoulder joint, a webbed neck and plain film findings of a hypoplastic scapula which is elevated and medially rotated with an associated omovertebral bone is likely to have which associated syndrome? a. Turner’s syndrome b. Down’s syndrome c. Klippel–Feil syndrome d. Neurofibromatosis e. Cleidocranial dysostosis

Answer 26

26. c. Klippel–Feil syndrome The collective findings described are of a Sprengel deformity of the shoulder. This occurs as a result of failure of descent of the scapula secondary leading to both cosmetic and functional impairment. The male:female ratio is 3:1 and it is associated with Klippel–Feil syndrome, a condition in which there is fusion of vertebral bodies, and renal anomalies

Question 27

27. A 52 year old woman presents to her GP with a longstanding history of lower back pain which has suddenly worsened in severity over the past few days. An urgent MRI scan of the lumbar spine shows a right paracentral disc protrusion at the L4/L5 level. The disc impinges on the lateral recess at this level. The most likely nerve to be affected is the: a. Cauda equina b. Lumbar plexus c. Right L4 d. Right L5 e. Right S1

Answer 27

27. d. Right L5 The right L5 nerve root is the most likely to be affected as it will be sitting in the right lateral recess at the L4/5 level. The L4 nerve root will be at the exit foramen and therefore if the protrusion affects only the lateral recess then this nerve will already have exited and therefore not be affected

Question 28

28. An 18 year old student who fell down two stairs and landed on her left knee attends A&E complaining of generalised knee pain but is able to weight bear. No acute bony injury is demonstrated on plain film, however a pedunculated lesion arising from the femoral metaphysis and extending away from the knee joint is seen. The lesion shows continuity with both the marrow and the cortex. The most likely diagnosis is: a. Osteochondroma b. Osteoblastoma c. Osteoid osteoma d. Chondroblastoma e. Chondromyxoid fibroma

Answer 28

28. a. Osteochondroma The description is classic for an osteochondroma or osteocartilagenous exostosis. These lesions are the most common benign growths of the skeleton, are usually found incidentally and are usually asymptomatic unless complications arise. Complications include fracture, vascular compromise, bursa formation and malignant transformation into chondrosarcoma.

Question 29

29. A 70 year old male presents with increasing pain in his right hip over the past month. There is no specific history of trauma. A plain radiograph demonstrates the presence of an incomplete fracture of the femoral neck arising from the lateral (convex) side. What is the most likely underlying abnormality of the femoral neck? a. Osteomalacia b. Metastasis c. Osteoid osteoma d. Infection e. Paget’s disease

Answer 29

29. e. Paget’s disease Incremental fractures (banana fracture) along the convex side of the bone are classically associated with Paget’s disease. These most commonly occur in the femur where they cause lateral bowing, and the tibia where they cause anterior bowing. Compression fractures of the vertebrae are also associated with Paget’s

Question 30

30. A 75 year old woman presents with increasing pain in her left hip. She had a total hip replacement eight years ago on this side which has been asymptomatic ever since. Plain radiographs demonstrate a lucent line at the bone cement interface of the femoral component. The likely cause for this is: a. Infection b. Metastasis c. Loosening d. Myeloma e. Trauma

Answer 30

30. c. Loosening Early changes (less than six months) are almost always due to infection. Up to four years, infection remains the most likely cause, but after this point loosening becomes more common. Every year, 38 000 hips are replaced in the UK. A routine postoperative film is usually performed; an excessively varus stem may lead to loosening.

Question 31

31. A 17 year old patient complains of lower thoracic back pain. Plain radiographs of the thoraco-lumbar spine show wedging of multiple vertebrae at the thoraco-lumbar junction, multiple limbus vertebrae, an increase in the AP diameter with a reduction in the sagittal height of multiple vertebrae, and multiple endplate defects. What is the unifying diagnosis? a. Scheuermann’s disease b. Ankylosing spondylitis c. Mycobacterium tuberculosis d. Hyperparathyroidism e. DISH

Answer 31

31. a. Scheuermann’s disease These are the classical appearances of Scheuermann’s disease. This condition usually presents at puberty and consists of vertebral wedging, endplate irregularity and narrowing of the intervertebral disc spaces. The most common location is in the lower thoracic and upper lumbar spine. Schmorl’s nodes are often present.

Question 32

32. A 70 year old patient complains of back pain and leg pain after walking 50 metres. Plain radiographs show an anterior slip of L4 relative to L5. The spinous process of L4 is also noted to have moved anterior to the L5 spinous process. What type of spondylolisthesis does this represent? a. Traumatic b. Degenerative c. Spondylolytic d. Dysplastic e. Pathological

Answer 32

32. b. Degenerative This is the classical description of the symptoms and radiology of a degenerative spondylolisthesis. Degenerative spondylolisthesis is usually symptomatic due to spinal stenosis and narrowing of neural foramen. This most commonly occurs at the L4/5 level. Spondylolisis is a defect in the pars interarticularis between superior and inferior articulating processes

Question 33

33. A 56 year old male is admitted under the orthopaedic team with increasingly severe lower back pain which started three weeks ago. MRI demonstrates an oedematous L4/5 intervertebral disc, marked loss of disc material and oedematous adjacent endplate changes. There is associated paravertebral inflammatory tissue and a small amount of pus within the residual disc space. The findings are consistent with infective discitis. What is the most likely causative organism? a. Mycobacterium tuberculosis b. Streptococcus pyogenes c. Staphylococcus aureus d. Escherichia coli e. Salmonella

Answer 33

33. c. Staphylococcus aureus The most common cause of infective discitis is Staphylococcus aureus, which gives the above typical findings. The only other relatively common cause is Mycobacterium tuberculosis, which typically spares the disc until late and usually has a large amount of associated pus

Question 34

34. A 25 year old male is involved in a 60 mph road traffic accident with a head-on collision. He was wearing a seat-belt but his car did not have an air-bag. A screening lateral radiograph of the cervical spine shows the following findings: an angular kyphosis centred at C4/C5, a 1mm anterior slip of C4 on C5, and widening of the interspinous space posteriorly. What is the likely mechanism for this injury? a. Lateral compression b. Flexion c. Extension d. Combination e. Rotation

Answer 34

34. b. Flexion This describes the typical appearance for a flexion injury as well as the typical mechanism. This would represent a potentially unstable fracture and immobilisation would be essential until further management decisions are made. Flexion teardrop injuries are more common in the lower cervical spine and extension teardrop injuries are more common in the upper cervical spine.

Question 35

35. A young man presents to his GP complaining of longstanding back pain. He says he has been diagnosed with a ‘syndrome’ in the past but cannot remember the details. Which of the following signs is more likely to suggest a diagnosis of homocystinura than Marfan’s syndrome? a. Arachnodactyly b. Osteoporosis c. Scoliosis of the spine d. Autosomal dominant inheritance e. Upward lens dislocation

Answer 35

35. b. Osteoporosis Osteoporosis is a feature of homocystinuria and occurs in 75% of cases, often causing bowing and fracture of the long bones. The other features are all more suggestive of Marfan’s syndrome. Although arachnodactyly does occur in homocystinuria (in 30% of cases), it occurs in 100% of people with Marfan’s syndrome. Homocystinuria has an autosomal recessive mode of inheritance.

Question 36

36. A 56 year old woman slips off the pavement onto the road and her outstretched foot is run over by a passing car. She has immediate severe midfoot pain. Plain radiographs taken on arrival at the emergency department confirm a Lisfranc fracture dislocation of the midfoot. Which two bones does the Lisfranc ligament attach to? a. First metatarsal and intermediate cuneiform b. First metatarsal and medial cuneiform c. Second metatarsal and medial cuneiform d. Second metatarsal and intermediate cuneiform e. First and second metatarsals to the medial and intermediate cuneiforms

Answer 36

36. c. Second metatarsal and medial cuneiform The Lisfranc ligament attaches between the second metatarsal and medial cuneiform, which is why an injury to this ligament allows the second to fifth metatarsals to drift laterally once they have lost this stabilisation. This is therefore an unstable injury and requires rapid immobilisation. This is a vital injury to detect as long-term sequelae will often result from a delayed diagnosis.

Question 37

37. A 24 year old man suffers a short oblique fracture of his distal tibia from a direct blow during a football game. He is treated with an intramedullary nail with a good reduction being achieved. Fourteen days later the foot becomes very tender, red and swollen but all haematological and biochemical parameters remain normal. Plain radiographs show spotty osteoporosis and subchondral erosions. Which of the following is the most likely diagnosis? a. Disuse osteoporosis b. Charcot joints c. Infection d. Regional sympathetic dystrophy e. Rheumatoid arthritis

Answer 37

37. d. Regional sympathetic dystrophy This is the typical appearance, history and imaging findings for regional sympathetic dystrophy. This may occur following fractures or secondary to other pathologies such as primary or secondary bone tumours. There is overactivity of the sympathetic nervous system causing pain, swelling and hyperaemia with excessive bone resorption. This is usually in a periarticular distribution and may simulate other disease processes

Question 38

38. A 25 year old woman attends A&E after falling onto her right hand. A plain film of her hand is taken in order to exclude fracture. No bony injury is seen. On examination, however, there is painless swelling of the right index finger which she says has been present for a few weeks. Incidental note is made of a small central lesion within the medullary cavity of the middle phalanx of the index finger. There is no cortical breakthrough or periosteal reaction but there is bulbous expansion of the bone with thinning of the cortex. The lesion contains dystrophic calcifications. This is most likely to represent: a. Giant cell tumour of the tendon sheath b. Unicameral bone cyst c. Brown tumour d. Enchondroma e. Epidermal inclusion cyst

Answer 38

38. d. Enchondroma This lesion is most likely to be an enchondroma. This is a benign cartilaginous growth in the medullary cavity and is usually asymptomatic. It most commonly occurs in the small bones of the hands and wrist but may also occur in the proximal humerus and proximal femur. Epidermoid inclusion cysts are usually in the distal phalangeal tuft and there is often a history of trauma. A bone cyst would be unusual in the phalanges

Question 39

39. A 72 year old woman presents to her GP with pain in her right shoulder which is worse on movement. Plain films of the right shoulder show loss of subacromial space and superior subluxation of the humeral head. She is referred for an ultrasound with a suspected supraspinatus tear. Which is the best position of the arm for visualisation of the free edge of the supraspinatous tendon? a. Adduction and internal rotation b. Abduction and internal rotation c. Adduction and external rotation d. Abduction and external rotation e. Flexion and internal rotation

Answer 39

39. a. Adduction and internal rotation The best position for visualising the supraspinatous tendon is with the patient’s arm in adduction and internal rotation. Often the patient may be asked to place the back of their hand onto their back, or alternatively asking them to simulate putting the hand into the back pocket of their trousers. The most medial part of the tendon when imaged transversely is the free edge – this is where the majority of supraspinatous tears occur.

Question 40

40. A 57 year old man with increasing pain and stiffness in his hands and feet and worsening back pain presents to his GP. Plain films of his hands show sclerosis of the terminal phalanges and several ‘pencil-in-cup’ erosions. There is destruction of the interphalangeal joint of his right great toe with exuberant periosteal reaction. There is also erosion of the posterior margin of the calcaneus. The most likely diagnosis is: a. Reiter’s syndrome b. Ankylosing spondylitis c. Rheumatoid arthritis d. Psoriatic arthritis e. Osteoarthritis

Answer 40

40. d. Psoriatic arthritis This is usually HLA B27 positive and is associated with skin and nail changes in the majority of cases. The hands are often described as having sausage digits, and erosions with ill-defined margins are characteristic. Sacroiliitis is often present and most often bilateral. Within the axial skeleton, there is often large bulky vertically orientated soft-tissue ossification giving a ‘floating’ osteophyte appearance

Question 41

41. A 20 year old student complains of a six-week history of pain and tenderness in his right thigh associated with a soft-tissue mass. There is no definite history of trauma. CT of the region shows a mass in the right distal femur with well-defined mineralisation at the periphery and a less distinct lucent centre. On plain film, there is faint calcification within the lesion and a radiolucent zone separating the lesion from bone. The most likely cause is: a. Tumoural calcinosis b. Osteomyelitis c. Myositis ossificans d. Parosteal sarcoma e. Osteosarcoma

Answer 41

41. c. Myositis ossificans Often there is no distinct history of trauma, although this is the most common cause. It usually occurs in the large muscles of the extremities and in the early stages it can be difficult to distinguish from soft-tissue sarcomas. It is, however, separate from bone, unlike parosteal sarcoma and post-traumatic periostitis. This is a self-limiting condition, most commonly occurring in young athletic adults, with resorption occurring in approximately one year

Question 42

42. A 60 year old man is referred for an MRI of his left upper leg after noticing a slowly enlarging firm mass measuring approximately 7–8 cm in maximum diameter. The mass is located in the quadriceps muscle group and is causing cortical erosion of adjacent bone. There are poorly defined calcifications within it and MR shows a poorly defined lesion which is isointense to muscle on T1-weighted imaging and hyperintense on T2-weighted imaging. The most likely diagnosis is: a. Malignant fibrous histiocytoma b. Benign fibrous histiocytoma c. Liposarcoma d. Fibrosarcoma e. Elastofibroma

Answer 42

42. a. Malignant fibrous histiocytoma Soft-tissue malignant fibrous histiocytoma is the most common primary malignant softtissue tumour of later adulthood. It is most commonly seen in the lower extremities. It has a metastatic rate of 42% and most commonly metastasises to the lung. Osseous malignant fibrous histiocytoma presents as a painful, tender, rapidly enlarging mass and most commonly arises in the metaphysis of long bones.

Question 43

43. A 27 year old man who attends A&E following an alleged assault is shown to have a left-sided longitudinal temporal bone fracture. Which of the following is a correct association? a. Facial nerve palsy in 50% of cases b. Incudostapedial joint dislocation c. Sensorineural hearing loss d. Ophthalmoplegia e. Rhinorrhoea

Answer 43

43. b. Incudostapedial joint dislocation Longitudinal fractures of the temporal bone are more common than transverse fractures and account for over 85% of temporal bone fractures. They are associated with otorrhea, conductive hearing loss, pneumocephalus, herniation of the temporal lobe and incudostapedial dislocation. Transverse fractures are associated with sensorineural hearing loss, and a higher percentage of facial nerve palsies

Question 44

44. A 24 year old woman presents with a painless mass on the dorsal aspect of the right index finger measuring approximately 11 cm. MRI shows a lobulated lesion which has low signal intensity on both T1- and T2-weighted imaging. Which of the following is the most likely diagnosis? a. Haemangioma b. Lipoma c. Ganglion cyst d. Giant cell tumour of the tendon sheath e. Neurilemmoma

Answer 44

44. d. Giant cell tumour of the tendon sheath This is a benign lesion thought to represent an extra-articular form of pigmented villonodular hyperplasia. This is low signal on both T1- and T2-weighted imaging due to haemosiderin deposition. It most commonly affects the fingers and characteristically lies along a tendon sheath

Question 45

45. A dental radiograph of a 47 year old woman shows loss of the lamina dura of the majority of the teeth. Which of the following would be a possible cause? a. Osteopetrosis b. Hypoparathyroidism c. Scleroderma d. Sickle cell anaemia e. Myeloma

Answer 45

45. c. Scleroderma The other causes of loss of the lamina dura include Cushing’s disease, Paget’s, hyperparathyroidism, osteoporosis, osteomalacia, leukaemia, metastases and Langerhans’ cell histiocytosis. Both osteopetrosis and hypoparathyroidism cause thickening of the lamina dura of the teeth.

Question 46

46. A 28 year old long-distance runner is to undergo MR arthrography of the hip joint for a suspected labral tear. Which of the following statements is correct regarding MR arthrography? a. A solution of 20mmol/L gadopentetate dimeglumine is injected into the hip joint under fluoroscopic guidance b. Patients with developmental dysplasia of the hip are at increased risk of labral tears c. A communication between the joint capsule and the iliopsoas bursa is always pathological d. T2-weighted imaging is used to visualise the high signal of the gadopentetate dimeglumine solution e. The normal labrum has uniformly high signal on T1-weighted imaging

Answer 46

46. b. Patients with developmental dysplasia of the hip are at increased risk of labral tears The increased risk of labral tears in developmental dysplasia is due to the increased stress placed upon the acetabular rim and labrum. A communication between the joint capsule and iliopsoas bursa has been described as a normal finding in 10–15% of patients. A dilute solution of 0.2mmol/L gadopentetate dimeglumine solution would usually be used for arthrography. A normal labrum has uniformly low signal on T1-weighted imaging with slightly increased signal on gradient echo imaging. Appearances on T2-weighted imaging can be more variable.

Question 47

47. A 24 year old woman presents with worsening frontal headaches and a sixth nerve palsy. A non-enhanced CT shows a lesion situated within the clivus with associated bony destruction; there is soft-tissue extension into the nasopharynx. MRI shows a large inter-osseous mass which is isointense to brain T1-weighted imaging and hyperintense on T2. The most likely diagnosis is: a. Sphenoid sinus cyst b. Meningioma c. Nasopharyngeal carcinoma d. Metastasis e. Spheno-occipital chordoma

Answer 47

47. e. Spheno-occipital chordoma The most likely cause is a spheno-occipital chordoma. This is associated with bony destruction in 90% of cases and is most usually within the clivus. Other sites include the sella, petrous temporal bone, floor of middle cranial fossa and jugular fossa. Sacrococcygeal chordoma is the most common subtype of chordoma and is usually located with the fourth or fifth sacral segments. Vertebral/spinal chordoma accounts for only 15–20% of all chordomas and is most often situated in the cervical spine.

Question 48

48. Regarding scaphoid fractures, which of the following statements is correct? a. 80% of scaphoid fractures occur at the waist b. Approximately 5% of scaphoid fractures are complicated by avascular necrosis c. Injury is typically due to hyperextension d. Up to 60% of scaphoid fractures cannot be seen on initial radiograph e. The specificity of CT in diagnosing scaphoid fractures is 60–70%

Answer 48

48. c. Injury is typically due to hyperextension The scaphoid bone is the most commonly fractured carpal bone and the mechanism is usually a fall onto the outstretched hand – ie. hyperextension of the wrist. The reported sensitivities and specificities of CT are 89–97% and 85–100%, respectively. The high negative predictive value of CT (96.8–99%) makes it very useful for ruling out a fracture. Scaphoid fractures are missed on initial radiographs in up to 30% of cases. (Ref: Kaewlai R et al. Multidetector CT of carpal injuries: anatomy, fractures, and fracturedislocations.

Question 49

49. A 24 year old man is involved in a road traffic accident. On arrival in A&E he is haemodynamically unstable and there is concern regarding pelvic fracture and associated active extravasation. On multidetector CT, which of the following features is more suggestive of pseudoaneurysm than active extravasation? a. Ill-defined area of high attenaution on arterial phase imaging b. Presence of a haemoperitoneum c. Washout of the high-attenuation area on delayed imaging d. Layering appearance on delayed imaging e. Haemodynamically unstable patient

Answer 49

49. c. Washout of the high-attenuation area on delayed imaging Washout of the high-attenuation area is one of the features of a pseudoaneurysm. A pseudoaneurysm is likely to be adjacent to a vessel and whilst there will be a relatively well-defined area of high attenuation on arterial phase imaging, this will diminish in intensity on five-minute delayed imaging. In contrast to this, an area of active extravasation will often appear as a jet of high attenuation which continues to collect and enlarge on delayed phase imaging

Question 50

50. A 27 year old woman is brought into A&E following a road traffic accident in which she was knocked down by a car. On arrival she has a GCS of 15 but is haemodynamically unstable and on examination she has abdominal bruising. The A&E consultant has performed a FAST (focused assessment with sonography in trauma) scan in resus and cannot see evidence of free fluid. What is the approximate minimal detectable fluid volume by FAST scanning? a. 10 ml b. 50 ml c. 100 ml d. 200 ml e. 500 ml

Answer 50

50. d. 200 ml The approximate minimal detectable fluid volume is 200 ml. The distribution of free fluid will be determined by both anatomical and physiologic factors and therefore the sensitivity of the scan will depend upon the areas scanned. Ultrasound is often used in conjunction with multidetector CT, particularly in the management of patients who have been involved in trauma.

Question 51

51. An A&E SHO has asked you to review a paediatric cervical spine plain film which has been performed on a child who has been involved in a road traffic accident. He is unsure as to whether or not the appearances are normal for a paediatric cervical spine film. Which of the following findings is more likely to represent a true cervical spine injury than a normal variant? a. Absence of usual cervical lordosis b. Widening of the prevertebral soft tissues in expiration c. Increased distance between the tips of the C1 and C2 spinous processes in flexion d. Wedging of the anterior aspect of the C3 vertebral body e. A 7mm gap between the occipital condyles and the condylar surface of the atlas

Answer 51

51. e. A 7mm gap between the occipital condyles and the condylar surface of the atlas This is highly suggestive of craniocervical injury; these injuries are often fatal and are often caused by sudden deceleration. Radiologic evaluation of this injury can be difficult but is crucial in determining further management. The remainder of the findings above can all be normal variants in the paediatric cervical spine and therefore should be interpreted with care.

Question 52

52. A 24 year old man has injured his right ankle playing football. The A&E SHO has asked your opinion on the plain radiographs. These show a widening of the medial joint space on the AP ankle view but no evidence of fracture, and an oblique fracture of the proximal shaft of the fibula. This is the typical appearance for which of the following fractures? a. Weber B b. Maisonneuve c. Pilon d. Dupuytren’s e. Fibula stress fracture

Answer 52

52. b. Maisonneuve This is the description of a Maisonneuve fracture (sometimes classified as Weber C3). This injury is often overlooked as the patient may complain only of ankle pain and hence a full tibia/fibula plain film is not taken. This fracture is often associated with ligamentous injury at the ankle, most usually of the anterior talofibular ligament and the postero-inferior talofibular ligament.

Question 53

53. An 18 year old man undergoes a Tc MDP bone scan to investigate pain in the right hip. A ‘hot’ lesion is seen in the right proximal femur. No other lesions are seen. Which of the following lesions would appear as ‘hot’ on a Tc MDP bone scan? a. Osteopoikilosis b. Fibrous cortical defect c. Acute fracture within 12 hours of injury d. Fibrous dysplasia e. Haemangioma

Answer 53

53. d. Fibrous dysplasia The most common site of monostotic fibrous dysplasia is the ribs, followed by proximal femur and craniofacial bones. Three-quarters of cases present before age 30. Other benign lesions causing a ‘hot’ on bone scan include Paget’s disease, brown tumours, aneurysmal bone cysts, osteoid osteoma and chondroblastoma. Acute fractures are not usually ‘hot’ until after the first 24–48 hours.

Question 54

54. A three month old boy presents with several small painful soft-tissue swellings which have developed over the mandibular region and the right clavicle. Plain films show marked periosteal new bone formation and localised soft-tissue swelling. There is also bone expansion with remodelling of old cortex. The most likely diagnosis is: a. Caffey disease b. Hypervitaminosis A c. Infantile myofibromatosis d. Scurvy e. Kinky hair syndrome

Answer 54

54. a. Caffey disease The most likely diagnosis is Caffey disease. This is a relatively rare self-limiting condition which usually presents before six months of age. The mandible is the most common site and accounts for 80% of cases, followed by the clavicle and the upper limb bones.

Question 55

55. A 29 year old woman presents with a painful right knee which has been worsening over the previous few weeks. A plain film of the right knee shows an oval expansile lesion with a radiolucent centre in the metaphyseal region of the proximal tibia. There is a sclerotic margin and geographic bone destruction. There are internal septations and stippled calcification. There is no periosteal reaction. The most likely diagnosis is: a. Non-ossifying fibroma b. Chondroblastoma c. Giant cell tumour d. Chondromyxoid fibroma e. Chondrosarcoma

Answer 55

55. d. Chondromyxoid fibroma This is most commonly seen in the second and third decades and the most common site is the long bones, most often the proximal tibia and distal femur. Non-ossifying fibroma is usually asymptomatic. The appearances of a chondroblastoma would be similar but this would most likely be epiphyseal in location and usually presents in a slightly younger age group.

Question 56

56. A 56 year old woman who has had chronic wrist pain since a fall several months previously is referred for an MR arthrogram of her wrist with a suspected triangular fibrocartilage complex (TFCC) tear. Which of the following would be the best sequence for visualising a TFCC tear? a. T1 axial b. T2 coronal c. Gradient echo sagittal d. T2 sagittal e. T1 sagittal

Answer 56

56. b. T2 coronal The best sequence would be a T2 or T2* image for detecting a tear. This is also a useful plane in which to assess for ulnar variance; positive ulnar variance has an association with perforations. The central portion of the articular disc is not well vascularised and therefore a tear in this portion will heal poorly. The peripheral portion, however, has been vascularised.

Question 57

57. A 64 year old woman undergoes MRI of her left knee for investigation of chronic knee pain. Which of the following would be considered an abnormal finding on MR? a. Bowing of the posterior collateral ligament on sagittal imaging b. Low signal ACL on T1-weighted imaging c. High signal around the MCL on T2* on coronal imaging d. Low signal of the menisci on both T1- and T2-weighted imaging e. Medial patellar plica

Answer 57

57. c. High signal around the MCL on T2* on coronal imaging The only abnormal finding is the presence of high signal around the MCL on T2* imaging. This would represent oedema or haemorrhage around the MCL and may be associated with a tear. Bowing of the PCL occurs when the knee is extended. A medial patellar plica is a normal finding in approximately 50% of the population. This is an embryological remnant from when the knee was divided into three compartments

Question 58

58. A 53 year old woman attends A&E with a short history of dull right heel pain. She is otherwise fit and well and there is no history of trauma. Plain radiographs of the right foot and ankle reveal a 2 cm expansile non-aggressive lesion in the calcaneum. It has a thin, well-defined sclerotic border. There is no periosteal reaction but there is a small calcified central nidus. The most likely cause of the lesion is: a. Aneurysmal bone cyst b. Intra-osseous lipoma c. Lipoblastoma d. Fibrous dysplasia e. Desmoplastic fibroma

Answer 58

58. b. Intra-osseous lipoma The calcaneum is a common location for an intra-osseous lipoma. They do, however, also occur in the extremities, skull and mandible. There is no periosteal reaction unless there is an associated fracture. Imaging features would be similar to those of a unicameral bone cyst. They are often asymptomatic but can present with localised bone pain

Question 59

59. A three-year-old boy attends A&E with a history of a seizure. He has known congenital cardiomyopathy. A chest radiograph shows sclerosis and expansion of several ribs. Previous plain films have shown bone islands within the vertebrae and long bones and bone cysts within the phalanges. Which of the following conditions would be likely to underly these findings? a. Down’s syndrome b. Tuberous sclerosis c. Sturge–Weber syndrome d. Neurofibromatosis e. Sarcoidosis

Answer 59

59. b. Tuberous sclerosis This is a multi-system autosomal dominant disorder affecting the central nervous system, kidneys, lung and heart. The classic triad of facial angiofibroma, epileptic seizures and mental retardation is only seen in approximately 30% of patients. Skeletal abnormalities include sclerotic calvarial patches or ‘bone islands’, thickening of diploe, expansion and sclerosis of ribs and periosteal thickening of long bones. Gracile ribs are often seen in association with Down’s syndrome

Question 60

60. A 27 year old man falls onto his right hand during a game of rugby. He attends the A&E department and a plain film of the right hand shows a comminuted fracture through the base of the thumb metacarpal with an intra-articular component. This is the description of which of the following fractures? a. Rolando’s fracture b. Bennett’s fracture c. Gamekeeper’s thumb d. Boxer’s fracture e. Barton’s fracture

Answer 60

60. a. Rolando’s fracture This is the classic description of a Rolando’s fracture. A Bennett’s fracture is also a fracture of the base of the first metacarpal but with no comminution; this fracture is often less stable than a Rolando’s fracture and more often requires surgical fixation. A ‘gamekeeper’s thumb’ often occurs as the result of forced abduction of the thumb and results in disruption of the ulnar collateral ligament.