Msk -- Hand And Wrist

Front 1

What is the differential diagnosis of lucent finger lesion?

Back 1

EGGS AN' SPAM
E = Enchondroma and epidermoid cyst
G = Glomus tumor
G = Giant cell tumor, Giant cell reparative granuloma (foreign body granuloma)
S = Solitary bone cyst
A = ABC
S = Sarcoidosis
P = Parathyroid causes (Brown tumor), pseudotumor of hemophilia
A = Arthritis (subchondral cysts, erosions)
M = Mets (lung, myeloma), Maffucci.

Fibrous dysplasia can also result in a lucent lesion in the hand.

Front 2

1. What are the imaging findings of madelung deformity?
2. What are the etiologies of madelung deformity?

Back 2

1. Triangular configuration of the distal radius and ulna with wedging of the proximal carpal bones between the distal radius and ulna. The ulna is usually dorsally subluxed. Because the carpal bone relationships are abnormal, there are early degenerative changes.
2.
- Trauma and infection result in fusion of the medial growth plate of the radius while the lateral joint space continues to grow. Usually result in unilateral madelung deformity.
- Turner syndrome: look for shortening of the 4th metacarpal; results in bilateral madelung deformity.
- Skeletal dysplasia: multiple enchondromatosis, mulitple hereditary exostoses, epiphyseal dysplasia, mesomelic dwarfism (dyschondrosteosis)

Front 3

1. What are the imaging features of glomus tumors?
2. What is etiology of glomus tumor?

Back 3

- Lesion is located in the soft tissues of the nail bed (not intramedullary) and leads to extrinsic erosion.
- Glomus tumors are hamartomas that arise from neuromyoarterial glomus (normal, specialized vascular anastomotic complex surrounded by nerve elements) that functions in the regulation of body temperature.

Front 4

1. What is the etiology of epidermoid inclusion cyst?
2. What are the most common locations of an epidermoid inclusion cyst?
3. What is the radiologic appearance of epidermoid inclusion cyst?

Back 4

1. Post-traumatic lesions that result from penetrating trauma in which dermoid elements are implanted into the bone.
2. Seen most commonly in the phalanges and skull.
3. Circumscribed lucent, rounded lesion with sclerotic rim causing destruction and expansion of the phalanx.

Front 5

1. What are the radiographic appearance of sarcoidosis?

Back 5

1. Sarcoid granulomas may occur within or adjacent to the bone resulting in puchned-out cortical erosions (mimicking gout) or central lytic lesions within the medullary cavity. The most common appearance in the bone is lace-like or honeycomb involvement. The lucent regions represent solid sarcoid granulomas replacing bone.
Asymmetric soft tissue swelling may also be present.

Front 6

1. What is the DDX of acroosteolysis?

Back 6

1. Hyperparathyroidism
2. Psoriasis
3. Scleroderma
4. Thermal injury (burns or frostbite) -- involves the phalanx and joint, and if extensive can also involve the middle phalanx. Can also see dystrophic calcifications.
5. Diabetic neuropathy
6. Pyknodysostosis
6. Leprosy
7. Lesch-Nyhan disease
8. Raynaud's disease

Front 7

1. What is the ddx of expanded tubular bones of the hands and feet?

Back 7

- Hemoglobinopathies (beta thalassemia, sickle cell disease)
- Fibrous dysplasia
- Gaucher disease
-

Front 8

1. What are the different types of distal radial fractures?

Back 8

1.
- Colles fracture: fracture of the distal metaphysis of the radius with dorsal angulation and displacement leading to a 'silver fork deformity'.
- Smith fracture: "reverse Colles fracture". Leads to volar displacement of the fracture fragment.
- Barton fracture: distal radial fracture-dislocation involving the dorsal RIM of the radius. Looks like Colles fracture but only the rim of the radius is involved.
- Die punch fracture:

http://www.radiologyassistant.nl/en/476a23436683b

Front 9

1. What are the imaging findings of psoriatic arthritis?
2. What are the different presentations in the hands?
3. What distinguishes paravertebral ossifications of psoriatic arthritis from syndesmophytes of AS?

Back 9

1. Soft tissue swelling (sausage digit), joint space narrowing, erosions with fluffy periostitis, "pencil-in-cup" deformity.
2.
- DIP joint polyarthritis
- Arthritis mutilans
- RA like symmetrical polyarthritis
- Monoarthritis
- Asymmetric oligoarthritis
- Sacroiliitis and spondylitis mimicing AS.
3. The paravertebral ossifications spare the annulus fibrosus.

Front 10

What is Kienbock's disease

Back 10

- AVN of the lunate.
- Associated with negative ulnar variance.
- Initially the lunate appears normal, but with time the bone becomes increasingly sclerotic. This is followed by loss of height, fragmentation, and subsequent collapse.

Front 11

1. What are imaging findings of erosive osteoarthritis?
2. What polyposis syndrome has erosive osteoarthritis?

Back 11

1. Bone proliferation (feature of OA) and erosions (feature of inflammatory arthritis).
- Distribution is typical of OA (distal)
- Central erosions + osteophyte formation gives the appearance of seagull.
- Ankylosis of the interphalangeal joint (not seen in osteoarthritis) can occur in the erosive form.
- Approximately 15% of patients with erosive osteoarthritis develop RA.
2. Cronkite-Canada syndrome: Gastrointestinal polyposis, hyperpigmentation of the skin, nail atrophy, and erosive osteoarthritis.

Front 12

1. What is a gamekeeper's thumb?
2. What is the mechanism of injury?
3. What is a Stener's lesion?

Back 12

1. Avulsion of the base of the proximal phalanx of the thumb at the attachment of the UCL.
2. Violent abduction of the thumb, which either disrupts the ulnar collateral ligament or causes an avulsion of its osseous insertion.
3. When the UCL ruptures, the torn end may become displaced superficially to the adductor pollicis aponeurosis. This complex, called Stener's lesion, may interfere with healing because the interposed aponeurosis pre vents apposition of the ligament to the bone. In this
situation, surgery has been advocated as the treatment.

of choice

Front 13

Wrist fractures and intercalated segmental instability

Back 13

Need to review this

Front 14

1. What are the causes of carpal tunnel syndrome?
2. What are the MRI findings in carpal tunnel syndrome?

Back 14

1.
- Idiopathic
- Tenosynovitis
- Masses (ganglion or neuroma)
- Synovial proliferation
- Diminished girth of the carpal canal from post-traumatic osseous changes and fibrosis.
2. MRI findings diagnostic of carpal tunnel include:
- compression and flattening of the median nerve
- increased signal intensity in the median nerve on T2W images
- bowing of the flexor retinaculum
- loss of the normal fat between the carpal bones and the tendons
- abrupt change of the diameter of the median nerve

Front 15

1. What is ulnar variance?
2. What is the etiology of ulnar impingement syndrome?
3. What are the imaging findings?

Back 15

1. Ulnar variance refers to relative length of the radius and ulna. If the ulna is short, the variance is negative. If the ulna is long, the variance is positive. Note that the position of the wrist can affect the ulnar variance. Supination causes relative ulnar shortening (S and S), whereas pronation causes relative lengthening.
2. Ulnar impingement syndrome is caused by positive ulnar variance resulting in compression of the distal ulnar on the medial articular surface of the lunate.
3.
- Flattening of the medial aspect of the lunate
- Sclerosis of the medial aspect of the lunate (low SI on both T1 and T2WI)
- Degenerative subchondral cysts formation.
- Injury to the TFCC
- In severe cases, the ulna subluxes dorsally and supination is impeded.

Front 16

What are the different types of the fractures of the base of the 1st metacarpal?

Back 16

There are 4 types of fractures involving the base of the 1st metacarpal.
1. Epibasal: extra-articular fractures through the first metacarpal base. The fracture line can be transversely or obliquely oriented.
2. Comminuted fracture: numerous bone fragments wtih more than one intra-articular fracture extension.
3. Bennet fracture: intra-articular two-part fracture; most common thumb fracture. Requires ORIF because it is hard to keep the fractures aligned 2/2 pull of the abductor pollicis longus on the metacarpal.
4. Rolando fracture: comminuted intra-articular three part fracture. The fracture pattern is often Y- or T-shaped. Rolando fracture is unstable as the volar fragment remains attached to the carpometacarpal joint, while the main dorsal fragment subluxes or dislocates dorsally and radially due to the unopposed pull of abductor pollicis longus.

Front 17

What are the features of arthritis due to scleroderma?

Back 17

** Severe resorption of the 1st carpometacarpal joint with radial subluxation of the 1st metacarpal bone.
- Erosions affecting the PIP and DIP joints of the digits.
- Soft tissue calcifications
- Conical shaped of the ends of the fingers
- Acro-osteolysis

Front 18

1. What is the DRUJ?
2. What contributes to its instability?
3. What is the most common type of DRUJ instability?
4. Define an Essex-Lopresti injury.

Back 18

1. Distal radio-ulnar joint. The distal ulna articulates with the radius at the sigmoid notch on the medial surface of the radius.
2. Fracture of the distal radius or ulna, ulnar minus variance, injuries to the triangular fibrocartilage complex.
3. Dorsal subluxation of the distal ulna is the most common type of instability that affects the DRUJ.
4. Fracture or fracture-dislocation of the radial head associated with disruption of the interosseous membrane between the radius and the ulna and with dislocation of the DRUJ.

Front 19

Tfc tears

Back 19

The radiocarpal joint, midcarpal compartment, and DRUJ do not normally communicate with one another.

Front 20

1. What is the ddx of short metacarpal?
2. What are the imaging findings of basal cell nevus syndrome?

Back 20

1.
- Pseudohypoparathyroidism
- Pseudopseudohypoparathyroidism
- Turner's syndrome
- Post infarction
- Post trauma
- Idiopathic
- Basal cell nevus syndrome.
2.
- Innmerable basal cell epitheliomas
- mandibular keratocysts (thus increased risk of ameloblastoma).
- brachydactyly (short 4th metacarpal)
- bifid ribs
- scoliosis
- intracranial calcification involving the falx cerebri, dura, and tentorium
- numerous mesenteric cysts

Front 21

SLE

Back 21

Soft-tissue swelling, juxta-articular osteoporosis, subluxations and dislocations, absence of erosions, absence of joint space loss,  calcification, osteonecrosis, bilateral / symmetric,

Front 22

Multicentric reticulohistiocytosis

Back 22

- Well-marginated erosions involving multiple joints, particularly in the hand;
- onset in middle age, F > M
- DDx: erosive osteoarthritis, gout; early psoriasis, Reiter’s
- Rare disease, maybe 200 cases in world literature
- Possibly associated with malignancy / paraneoplastic syndrome.

Front 23

Carpal dislocation

Back 23

4 Stages of injury: scapholunate dissociation (widening of the scapholunate interval), perilunate dislocation, midcarpal dislocation, and lunate dislocation.
- Lateral radiograph is essential to differentiate among different wrist dislocations.
- Scapholunate dissociation: widening of the scapholunate interval seen on PA radiograph.
- Perilunate dislocation: triangular shaped lunate on PA radiograph without normal articulation with the capitate on the frontal view; lunate articulates normally with the radius while capitate is dislocated dorsally. MC associated with scaphoid fracture (transcaphoid perilunate fracture-dislocation).
- Lunate dislocation: abnormal triangular configuration of the lunate on PA view without normal articulation with capitate; on lateral view, the lunate is volarly dislocated; capitate is normally aligned with the radius.
- Midcarpal dislocation: lunate and capitate are malpositioned in relation to the radius.

Front 24

What is DDX of absent radius/thumb?

Back 24

1. VACTERL
2. Trisomy 13
3. Trisomy 18
4. Fanconi anemia (aplastic anemia associated with limb anomalies, microcephaly, renal anomalies, hyperpigmentation).
5. Holt-Oram syndrome: affects bones in the arms and hands + cardiac abnormalities