Wrist

Which muscles attach on or close to the lateral epicondyle of the humerus?

Extensor carpi radialis longus and brevis, extension carpi ulnaris

Which muscles cross the wrist on the radial side?

Extensor carpi radialis longus and flexor carpi radialis

Which muscles cross the wrist on the ulnar side?

Extensor carpi ulnaris and flexor carpi ulnaris

Which muscles attach on the medial epicondyle of the humerus?

Flexor carpi ulnaris, flexor carpi radialis, palmaris longus

When hammering overhead, why are your wrist ulnar deviators working harder than when hammering at waist level?

you are working against gravity when hammering overhead and with gravity when hammering at waist level.

Why is the ulna not considered part of the wrist?

Because an articular disk is located between the ulna and the proximal row of carpals

Starting on the anterior surface of the ulnar side and moving in the direction of the radial side, name the muscles that cross the wirst. Go completely around the wrist.

Flexor carpi ulnaris, palmaris longus (with flexor digitorum superficailis and profundus deep to it), flexor carpi radialis (abductor pollicis longus, extensor pollcis long and brevis, which are primarily thumb muscles but also cross the wrist), extensor carpi radialis longus and brevis ( extensor digitorum, a finger extensor), and extensor carpi ulnaris .

The wrists motions have what type of end feels?

For wrist flex/ext and ulnar deviation, the end feel is soft tissue stretch For wrist radial deviation the end feel is bony

If you were shown a drawing of only a wrist joint, what landmarks could tell you if the drawing were a posterior or anterior view?

If the pisiform bone and hook of the hamate bone are visible, it would be the anterior side.

Extensor carpi ulnaris muscle

O: Lateral epicondyle of humerus I: Base of 5th metacarpal A: wrist extension, ulnar deviation N: radial nerve ( C6, C7, C8)

Extensor carpi radialis brevis muscle

O: Lateral epicondyle of the humerus I: Base of 3rd metacarpal A: wrist extension N: radial nerve (C6, C7)

Palmar longus muscle

O: Medial epicondyle of humerus I: Palmar facia A: Assistive in wrist flexion N: Median nerve (C6, C7)

Flexor carpi radialis muscle

O: Medial epicondyle of the humerus I: Base of the 2nd and 3rd metacarpals A: wrist flexion, radial deviation N: Median nerve ( C6, C7)

Flexor carpi ulnaris muscle

O: Medial epicondyle of the humerus I: Pisiform and base of the 5th metacarpal A: wrist flexion and ulnar deviation N: ulnar nerve (C8, T1)

Extensor carpi radialis longus muscle

O: Supracondylar ridge of humerus I: base of 2nd metacarpal A: Wrist extension, radial deviation N: radial nerve (C6, C7)

1. Name the bones of the wrist joint, starting laterally on the proximal row and going medially. Use the same order for the distal row.

Proximal row lateral to medial: scaphoid, lunate, triquetrum, pisiform. Distal row lateral to medial: trapezium, trapezoid, capitate, hamate.

Mnemonic to help remember the order of the wrist bone: Sam Likes To Push The Toy Car Hard

S- Scaphoid L- lunate T- triquetrum P- Pisiform T- Trapezium T- trapezoid C- capitate H- hamate

Which muscle, if present , is very easy to identify but has little functional importance.

The palmaris longus located on the anterior surface in the middle of the wrist.

Generally speaking, you use wrist muscles when hammering. However when extra force is needed you may use elbow or even shoulder muscles. Why does that create greater force?

You are using a longer lever arm and larger muscles.

3. Describe the wrist joints:

a. # of axes radiocarpal joint: 2 Intercarpal joint: 0 b. Shape of joint: Radiocarpal joint: condyloid Intercarpal joint: plane or irregular c. Joint motion allowed: radiocarpal joint: flex/ext, radial/ulnar deviation Intercarpal joint: gliding

2. Which wrist motions occur in: a. the sagittal plane around the frontal axis? b. the frontal plane around the sagittal axis? c. the transverse plane around a vertical (longitudinal) axis?

a. Wrist flexion/extension b. Wrist radial / ulnar deviation c. No wrist motions occur in the transverse plane around a vertical (longitudinal) axis.

prime movers for a. wrist flexion b. wrist extention c. radial deviation d. ulnar deviation

a. flexor carpi radialis, flexor carpi ulnaris b. extensor carpi radialis longus and brevis, extensor carpi ulnaris c. flexor carpi radialis, extensor carpi radialis longus d. flexor carpi ulnaris, extensor carpi ulnaris

What is the name of the bony landmark just proximal to the lateral epicondyle?

lateral supracondylar ridge