Wrist

Question 1

What is the most commonly dislocated carpal bone?

Answer 1

Lunate

Question 2

What is the mechanism for lunate dislocation?

Answer 2

FOOSH, squirts out between radius and capitate.

Question 3

What is a common concern with a lunate dislocation/injury?

Answer 3

Median nerve injury, AVN, fracture

Question 4

Describe the evaluation and management of a lunate injury>

Answer 4

Assess for excessive mobility due to ligamentous injury. Look for loss of the teacup sign on lateral films. Requires prompt reduction

Question 5

What is a colles fracture

Answer 5

• Fracture of lower end of radius, nearly always from falling on out stretched hand. - Fracture occurs transversely about 2 cm above distal end of radius. - Typically a dorsal hollow in lowest 1/3 of the forearm, but immediately below is a marked prominence by lower fragment’s being displaced backwards, referred to as “dinner fork deformity

Question 6

What is the most commonly fractured carpal bone and why?

Answer 6

Scaphoid. It translates forces to the radius.

Question 7

What is the best way to handle pain over the anatomical snuff box

Answer 7

Treat as a scaphoid fracture due to risk of AVN. Rather than wait 2 more weeks for film, Immobilize

Question 8

How do you find the lunate

Answer 8

palpate listers tubercle and the 3rd metacarpal. Lunate is in the divot between.

Question 9

What carpal bones are the most commonly injured and what is a unique characters of them

Answer 9

The lunate, scaphoid and trapezium, these are all generally considered very mobile, Pisiform is mobile as well but generally not a problem

Question 10

Which carpals are generally considered to be less mobile

Answer 10

Hamate, trapezoid and captivate. these are generally not injured.

Question 11

What should you be suspicious of if a person has thumb pain

Answer 11

An issue with the trapezium

Question 12

Describe the joint surface articular of the radoiocarpal joint

Answer 12

medial facet (46%) lunate lateral facet (43%) scaphoid inferior disk (11%) triquetrum

Question 13

Describe the distal radiounlar joint characteristics

Answer 13

-inclosed in a capsule with a articular disk - disk connects radius and ulna which functions between for supination and pronation - more distally, the triquetrum glides on the articular surface during wrist movements.

Question 14

What is the difference between carpal ligaments.

Answer 14

Volar are thicker and stronger Dorsal are thinner and fewer

Question 15

How do nodules present in the wrist and hand

Answer 15

if in the palm think trigger finger, if at the PIP think RA, if at the DIP think OA

Question 16

What does a clawing hand deformity mean?

Answer 16

this is an intrinsic minus hand. The share of the arches is maintained by the intrinsics.

Question 17

Describe flexion ROM of the wrist at the carpal level

Answer 17

–Proximal row:

• scaphoid, lunate, and triquetrum proximal surfaces move posteriorly, gliding occurs in a posterior direction on the radius and articular disc.

–Distal row:

• trapezium and trapezoid glide anterior on scaphoid,
• hamate and capitate move like the proximal row of carpal bones, gliding occurs in posterior direction on the proximal row.

Question 18

Describe Extension ROM of the wrist at the carpal level.

Answer 18

35 degrees of which is radiocarpal

–Proximal row:

•scaphoid, lunate, triquetrum distal surfaces move posteriorly and proximal surfaces move anteriorly. Gliding occurs in an anterior direction on the radius and articular disc.

–Distal row:

•hamate and capitate move like proximal row, gliding occurs in an anterior direction on proximal row, trapezoid and trapezium glide posterior on the scaphoid.

Question 19

Describe radial devation at each row of carpals

Answer 19

• Radial deviation 15-20 degrees
• >50% is midcarpal
• Proximal row of carpal bones glide in ulnar direction, scaphoid rotates around a transvers axis with its proximal surface gliding anteriorly, gapping occurs on the ulnar side as the triquetrum moves 1.5 cm away from the disc, carpal bones in the distal row rotate radially around their A-P axis, trapezi glide posterior on the scaphoid.

Question 20

Describe movement of the carpals during ulnar deviaiton

Answer 20

• 30-45 degrees
• >50% is radiocarpal
• proximal row of carpal bones glides in a radial direction, carpal bones in the distal row rotate ulnarly around their A-P axis, hamate rotates around its transverse axis with its proximal surface gliding anteriorly.

Question 21

Describe the convex/concave nature of the ulna and radius.

Answer 21

• Convex ulnar head on concave distal radius