Class Notes (839,150)
Canada (511,218)
Biology (1,140)
BIOL 2005 (40)

Forearm and Hand

2 Pages

Course Code
BIOL 2005
Elizabeth Nisbet

This preview shows 80% of the first page. Sign up to view the full 2 pages of the document.
Forearm and Hand Key Points: 1. Each joint only allows certain movements 2. Movement occurs about an axis of rotation (= reference line thru a joint about which movement occurs) 3. Position of muscles with relation to an axis of rotation allows you to know their effect 4. Prime movers = muscles that usually produce movement about an axis 5. Antagonists = muscles that oppose action of prime movers and stabilize joint I. Elbow Joint (humero-ulnar & humero-radial joints) a. Interlocking of bony surfaces => only flexion and extension b. Ligaments restrain abduction/adduction i. Medial: ulnar collateral ligament ii. Lateral: annular ligament c. Flexion is unrestrained; extension restrained by olecranon d. Flexor M: Brachialis (primary), Biceps Brachii (primary), Brachoraidalis, Pronator Teres e. Extensor M: Triceps Brachii (posterior compartment) II. Proximal/Distal Radio-Ulnar Joints a. Radius = lateral (thumb side); Ulna = medial (pinky side) b. Supination = palms face up; anatomical position = lateral rotation i. Limited by ligaments between radius, ulna, and wrist ii. Large size of biceps brachii => we are much stronger at supinating than at pronating our forearm iii. Muscles: Supinator, biceps brachii c. Pronation = palms facing down/posterior = medial rotation i. Medial rotation of humerus adds ~90 degrees to medial rotation ii. Muscles: pronator teres, pronator quadratus III. Wrist Joint (radiocarpal & intercarpal joints) a. Flexion/Extension i. Flexor Muscles 1. pass anterior to mediolateral axis 2. Muscles: Flexor carpi radialis, palmaris longus, flexor carpi ulnaris ii. Extensor Muscles 1. posterior to mediolateral axis 2. Muscles: extensor carpi radialis longus/ brevis, extensor carpi ulnaris b. Abduction/Adduction (occurs about anteroposterior axis) i. Abduction (radial deviation) 1. Flexor carpi radialis, extensor carpi radialis longus/ brevis, abductor pollicis longus ii. Adduction (ulnar deviation) 1. flexor carpi ulnaris, extensor carpi ulnaris iii. Palmaris Longus—NOT an abductor or adductor b/c it passes directly thru the axis of rotation IV. Carpometacarpal & Intermetacarpal Joints a. Generally severely restricted in movement due to ligaments b. NO muscles work on these joints except for digits 1 & 5 c. Digit 1 & 5 have opponens muscles which act to move digits in opposition
More Less
Unlock Document

Only 80% of the first page are available for preview. Some parts have been intentionally blurred.

Unlock Document
You're Reading a Preview

Unlock to view full version

Unlock Document

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.