xray anatomy hand

Question 1

what are the 17 bones found in the hands/wrist and identify them

Answer 1

pisiform, trapezium, triquetrium, trapezoid, scaphoid, hamate, lunate, capitate, metacarpals, phalanges

Question 2

what are the 4 types of joints found in hands

Answer 2

carpal-metacarpal, metacarpal-phalangeal, interphalangeal distal/proximal

Question 3

where can the sesamoid bones in hands be found

Answer 3

1. mainly 2 on the palmer side of the first metacarpal-phalangeal joint
2. others if present are on the other metacarpal-phalangeal joint
3. on the interphalangeal joint of thumb

Question 4

what is the difference between bases and head of the phalangeals

Answer 4

1. bases of distal and middle phalange have biconcave surface separated by median ridge
2. heads of proximal and middle phalange are narrower than bases with 2 condyles separated by shallow groove

Question 5

what is an unqualified tuft

Answer 5

expansion at distal margins of the distal phalanx

Question 6

what angle is the 1st metacarpal turned at compared to the others and how is its shape different

Answer 6

1. 45 degrees
2. shorter and thicker

Question 7

what bone does the medial facet of the base of 1st metacarpal articulate with

Answer 7

trapezium

Question 8

What clinical findings would you expect to see for a crush and direct impact injury?

Answer 8

• Patients who present with these injuries will usually be able to give a clear account of their injury
• Patients present with significant soft tissue swelling, pain, reduced or loss of range of movement (ROM) and often laceration of the affected digit
• Fractures which involve the nail bed need to be carefully assessed as the patient may be at risk of infection

Question 9

impact can cause the distal phalanx to be forcibly flexed while the extensor tendon remains taut. Radiographic findings typically show an avulsion fracture at the site of insertion of the extensor tendon. Fractures of the base of the middle phalanx may be caused by direct impaction forces and are often related to dislocations. Dislocation (usually dorsal) with or without associated fracture can occur from this mechanism.

Question 10

what is a mallet finger

Answer 10

Mallet finger, known as drop finger or baseball finger, is an injury to the tendon that straightens the tip of your finger (or thumb).

A mallet finger is an injury to the tendon that straightens the tip of the finger, causing it to bend. Sometimes there is also a small break in the bone.

Question 11

a volar plate strengthens the anterior aspect of the interphanagel joint, if there is hysperextension, where is the avulsion likely to be found

Answer 11

anterior aspect of the base of the middle phalanx.

Question 12

hyperad/bductions injuries to the digits affect what ligaments

Question 13

what 3 types of soft tissue in the hand can cause avulsion fractures in the phalanges

Answer 13

ulnar/radial collateral ligament
volar plate
extensor tendon

Question 14

on what 3 views can the 3 types of avulsion fractures on phalanges be seen and where

Answer 14

1. collateral ligament avulsions seen at base or head of phalanges on an AP/DP view
2. volar plate avulsions seen at palmer side of base/head of phalange on lateral view
3. extensor tendon avulsion seen at dorsal aspect of phalange on lateral view

Question 15

what is it called when the rupture of the extensor tendon results in dislocation not avulsion

Answer 15

mallet finger, flexion deformity at distal interphalangeal joint

Question 16

dislocations to the inter phalangeal joints are common

dislocations are described by which joint is affected and the direction of the phalanx distal to the joint relative to the phalanx proximal to the dislocated joint

Question 17

what is the major indication that there is a dislocation due to a fractured metacarpal

Answer 17

if joint space is not minimum 2mm wide (2mm joint space beneath metacarpals)

Question 18

when mechanism of injury is similar to the 5th metacarpal neck fracture so, when index of suspicion is high and a fracture to the head or neck isn’t present, scrutinise the base of the 4th and 5th metacarpals and the adjacent hamate

Question 19

when is a Bennetts fracture

Answer 19

oblique intra-articulate fracture (occasionally with dorsal subluxation of shaft) at the base of the 1st metacarpal

Question 20

a Ronaldo fracture is similar to a Bennetts but differs in what way

Answer 20

it is communited not obkliquer fracture

Question 21

an avulsion fracture to the base of the 1st proximal phalange is correlated to which ligament and is known as?

Answer 21

ulnar collateral ligament
‘skiers thumb’

Question 22

what is a salter Harris fracture?

Answer 22

fractures involving the physeal growth place and adjacent metaphysics and or epiphysis.

• an injury to this area will cause a fracture to the weakest point, which is the cartilaginous growth place and spare the stronger joint capsule (ligaments and tendons)
• only in paediatric

Question 23

what are the 5 different clarifications of the salter Harris fractures?

Answer 23

I = straight across
II = above
III = lower/below
IV = through
V = erasure/ compression

Question 24

Torus fractures are common in kids in their phalangeal areas with growth plates, what is this?

Answer 24

buckling/bulging of axial bone in areas of growth plates due to compression

Question 25

what do you call the benign lesions that can be found within bones and what do you call it when they are excessive

Answer 25

enchondroma
‘ olliers disease’

Question 26

how can enchondroma affect the bone

Answer 26

can cause fracture due to expansile nature and cortical thinning