Hand Anatomy & Clinical Relevance

Question 1

How do we refer to the digits of the hand in short-form?

Answer 1

D1 -> D5 starting at the thumb

Question 2

Whats different about the thumb and the other digits?

Answer 2

The thumb lacs a middle phalanx so only has one IP joint

Question 3

What shape is the pisiform bone?

Answer 3

Sesamoid

Meaning it’s a smooth surface embedded within a tendon for it to slide over

Question 4

Whats the commonest carpal bone to undergo arthritis?

Answer 4

Trapezium

Question 5

Which carpal bone sits within the tendon of the FCU?

Answer 5

Pisiform

Question 6

Which carpal bone is most commonly fractured?

Answer 6

Scaphoid

Question 7

Whats particularly dangerous about a proximal scaphoid fracture?

Answer 7

The proximal scaphoid lacks a good blood supply so theres a high risk of avascular necrosis (AVN)

Question 8

Whats a useful way to locate the flexor muscle of the forearm and the direction of their tendons?

Answer 8

Place the other hand on you forearm with the base of the thumb on the medial epicondyle.
Your four fingers should point down your forearm in the direction of each of the flexor muscles:
- Pinkie = FCU
- Ring = Palmaris Longus
- Middle = FCR
- INdex = Pronator Teres

Question 9

How do we isolate to test the Flexor Digitorum Profundus?

Answer 9

Isolate the DIP by holding the rest of the finger straight, this prevents the FDS from working as it affects all the joints

Question 10

How do we isolate the Flexor Digitorum Superficialis?

Answer 10

FDS has individual muscle bellies for each finger whereas the FDP has one for the whole hand.
So hold the other fingers out straight to isolate one finger preventing the FDP from working

Question 11

How many compartments are within the wrists extensor retinaculum?

Answer 11

6

Question 12

What muscle tendons are found in each compartment of the Extensor Retinaculum?

Answer 12

1 - EPB & APL
2 - ECRL & ECRB
3 - EPL
4 - Extensor Indices & Extensor Digitorum
5 - EDM
6 - ECU

Question 13

What tendons form the anatomical snuffbox?

Answer 13

Medially its the Extensor Pollicis Longus

Laterally its the Abductor Pollicis Longus

Question 14

What type of joint is the elbow?

Answer 14

Hinge

Question 15

What type of joint is the wrist?

Answer 15

Synovial Condylar

Question 16

What type of joint is the carpometacarpal?

Answer 16

Synovial Condylar

Question 17

What type of joint is the Metacarpophalangeal?

Answer 17

Synovial Condylar

Question 18

What type of joint is the carpometacapral joint of the thumb?

Answer 18

Saddle

Question 19

Describe the name changes of the subclavian artery>

Answer 19

Subclavian until the lateral border of the 1st rib
Axillary until lower border of teres major
Brachial until cubital fossa
Ulnar and radial until palm

Question 20

Which artery gives rise to which palmar arch?

Answer 20

Ulnar mostly contributes to the Superficial Palmar arch (also more distal)

Radial mostly contributes to the deep palmar arch (also more proximal)

Question 21

What arteries supply the fingers?

Answer 21

Digital arteries, branches of the palmar arches

Question 22

What happens to the dorsal venous arch as it drains into the forearm?

Answer 22

Becomes the cephalic vein laterally and the basilic vein medially

Question 23

What happens to the basilic and cephalic veins?

Answer 23

Basilic travels up the medial side becoming the brachial and then axillary

Cephalic travels laterally and drains into the axillary just below the clavicle

both connected by the median cubital vein across the cubital fossa

Question 24

What nerve supplies the Arm flexors?

Answer 24

Musculocutaneous

Question 25

What nerve supplies the arm extensors?

Answer 25

Radial

Question 26

What nerve supplies the forearm flexors?

Answer 26

Median - Most

Ulnar - FCU and FDP

Question 27

What nerve supplies the forearm extensors?

Answer 27

Radial along with the brachioradialis muscle

Question 28

What nerve supplies the muscles of the hand?

Answer 28

Mostly the Ulnar

Thenar muscles & 1st 2 lumbricals = Median