Lab 4 (exercise 10 & 12)

articulations

Location where bones meet, aka joints

Fibrous joints

composed of connective tissue fibers between bones

Example of fibrous joints

Suture-frontal and parietal bones

Gomphosis-teeth and mandible

Syndesmosis-distal tibia and fibula

synostosis

Complete fusion of two bones

Gomphosis (teeth) attach like a peg in a socket via

periodontal ligaments, a type of fibrous connective tissue.

Cartilaginous joint

cartilage between bones, allow for some movement.

Synchondrosis

Symphysis

Synchondrosis examples (plural: synchondroses)

include the epiphyseal plates in growing long bones (humeral head and shaft) and the joint between the first rib and the (costal cartilage) sternum.

symphysis

joint between two vertebral bodies. Its made of fibrocartilage and endures greater stress than hyaline cartilage

Synovial joints

are fluid-filled joints that allow for a wide range of motion, consisting of a synovial fluid, inner membrane, and a joint capsule. Most MOVABLE

joint capsule is made of

fibrous capsule and inner synovial membrane. The space inside a joint is called a synovial cavity

Each synovial joint end in

articular cartilage (ends made of hyaline cartilage cap)

Example of synovial joints

gliding

hinge

pivot

ellipsoid

saddle

ball and socket

The more movable a joint is, the more

unstable it becomes.

Modified synovial structures

Bursae (plural: bursa): sacs that cushion tendons and bones

Tendon sheaths: lubricate tendons as they slide (palm of hand)

Name joints and their movement ability

synarthrotic joints: immovable joints

amphiarthrotic: fibrous/cartilaginous semi movable

diarthrotic: freely movable

(synovial joint) plane or gliding joint

allow sliding movement between two superior and inferior flat surfaces. Ex. Facets of adjacent vertebrae joints.

(synovial joint) Hinge joints

allow angular movement in one plane, similar to a door hinge. Ex. Elbow and knee joints.

(synovial joint) pivot joints

allow rotational movement around a single axis. Ex. atlas and axis shaking head no

(synovial joint) ellipsoid/condyloid joints

allow significant movement in two planes, permitting flexion, extension, and some rotation. Ex. Wrist and base of phalanges

(synovial joint) saddle joints

havetwo concave surfaces that connect to each other. Ex. Thumb joint.

(synovial joint) ball and socket joints

allow rotational movement in multiple directions, made of spherical head in a round concavity. Ex. Shoulder and hip joints.

which joints are uniaxial, biaxial, and multiaxial.

Uniaxial joints allow movement in one plane: hinge, pivot, and gliding.

Biaxial joints allow movement in two planes: Ellipsoid

Multiaxial joints permit movement in multiple directions: ball and socket joints

Temporomandibular joint

only diarthrotic joint of the skull and is a hinge and gliding joint. Contains fibrocartilage (articular disk) that cushions mandibular condyle and temporal bone.

Actions

movement controlled by muscles. They can increase or decrease joint angles, and cause rotation.

Fixing a muscle

prevents motion in any direction. This happens when opposing muscles contract simultaneously.

Trapezius (Posterior muscles acting on shoulder and arm)

Origin: occipital protuberance, nuchal ligament, spinous processes of C7-T12

Insertion: Clavicle, acromion process, spine of scapula

Action: extends and abducts head, rotates and adducts scapula, fixes scapula

Innervation: Accessory (XL) nerve

Latissimus dorsi

Origin: T7-T12, L1-5, sacrum, iliac crest, ribs

Insertion: intertubercular groove of humerus

Action: Extends, adducts, and medially rotates arm depresses shoulder

Innervation: Thoracodorsal nerve

Deltoid

Origin: Clavicle, acromion process, spine of scapula

Insertion: Deltoid tuberosity of humerus

Action: abducts, flexes, and extends arm; medially and laterally rotates arm

Innervation: Axillary nerve

Rhomboideus major

Origin: Spines of T1-T4

Insertion: Inferior, medial border of scapula

Action: Adducts scapula

Innervation: Dorsal scapular nerve

Rhomboideus minor

Origin: Nuchal ligament, spines of C6-7

Insertion: Medial border of scapula at scapular spine

Action: Adducts scapula

Innervation: Dorsal scapular nerve

Levator scapulae

Origin: C1-4

Insertion: Superior angle of scapula

Action: Elevates scapula, abducts and rotates neck

Innervation: Spinal nerves C3-5, dorsal scapular nerve

Supraspinatus

Origin: supraspinous fossa

Insertion: greater tubercle of humerus

Action: abducts arm (stabilizes shoulder joint)

Innervation: suprascapular nerve

Infraspinatus

Origin: Infraspinous fossa

Insertion: greater tubercle of humerus

Action: extends and laterally rotates arm (stabilizes shoulder joint)

Innervation: Suprascapular nerve

Subscapularis

Origin: subscapular fossa

Insertion: lesser tubercle of humerus

Action: extends medially rotates arm (stabilizes shoulder joint)

Innervation: subscapular nerve

teres minor

Origin: lateral border of scapula

Insertion: greater tubercle of humerus

Action: Extends, laterally rotates, and adducts arm (stabilizes joint shoulder)

Innervation: axillary nerve

Teres major

Origin: Lateral border of scapula

Insertion: crest of lesser tubercle of humerus

Action: Extends, adducts, and medially rotates arm

Innervation: subscapular nerve

Triceps brachii

Origin: infraglenoid tuberosity of scapula, lateral and posterior surface of humerus

Insertion: Olecranon process of ulna

Action: extends and adducts arm, extends forearms

Innervation: Radial nerve

pectoralis major (anterior muscle of shoulders and arm)

Origin: clavicle, sternum, cartilages of ribs 1-7

Insertion: Crest of greater tubercle of humerus

Action: flexes, adducts, and medially rotates arm

Innervation: anterior thoracic nerves

pectoralis minor

Origin: ribs 3-5

Insertion: coracoid process of scapula

Action: depresses glenoid cavity, raises ribs 3-5

Innervation: anterior thoracic nerves

biceps brachii

Origin: supraglenoid tubercle, coracoid process of scapula

Insertion: radial tuberosity

Action: flexes arm, flexes forearm, supinates hand

Innervation: Musculocutaneous nerve

coracobrachialis

Origin: coracoid process of scapula

Insertion: midmedial shaft of humerus

Action: flexes and adducts arm

Innervation: musculocutaneous nerve

Brachialis (anterior muscles acting on the forearm)

Origin: anterior distal surface of the humerus

Insertion: coronoid process of ulna

Action: flexes forearm

Innervation: musculocutaneous and radial nerves

brachioradialis

Origin: lateral supracondylar ridge of humerus

Insertion: styloid process of radius

Action: flexes forearm

Innervation: radial nerve

Supinator

Origin: Lateral epicondyle of humerus, anterior ulna

Insertion: proximal radius

Action: supinates hand

Innervation: radial nerve

Pronator teres

Origin: medial epicondyle of humerus, coronoid process of ulna

Insertion: lateral, middle shaft of radius

Action: Pronates hand, flexes forearm

Innervation: median nerve

Pronator quadratus

Origin: distal part of anterior ulna

Insertion: distal radius

Action: pronates hand

Innervation: median nerve

palmaris longus (anterior muscles acting on the hand)

Origin: medial epicondyle of humerus

Insertion: palmar fascia

Action: flexes hand

Innervation: median nerve

flexor carpi radialis

Origin: medial epicondyle of humerus

Insertion: metacarpals 2 and 3

Action: flexes and abducts hand

Innervation: median nerve

flexor carpi ulnaris

Origin: medial epicondyle of humerus and ulna

Insertion: pisiform, hamate, metacarpal 5

Action: flexes and adducts hand

Innervation: ulnar nerve

flexor digitorum superficialis

Origin: medial epicondyle of humerus, coronoid process of ulna, proximal radius

Insertion: middle phalanges of digits 2-5

Action: flexes proximal and middle phalanges 2-5, flexes hand

Innervation: median nerve

flexor digitorum profundus

Origin: ulna, interosseus membrane

Insertion: distal phalanges of digits 2-5

Action: flexes phalanges. flexes hand

Innervation: median and ulnar nerve

flexor pollicis longus

Origin: anterior portion of radius and interosseus membrane

Insertion: distal phalanx of pollex

Action: flexes thumb and hand

Innervation: median nerve

flexor pollicis brevis

Origin: trapezium

Insertion: proximal phalanx of digit 1

Action: flexes thumb

Innervation: median and ulnar nerves

Abductor pollicis brevis

Origin: scaphoid, trapezium

Insertion: proximal phalanx of digit 1

Action: abducts thumb

Innervation: median nerve

Opponens Pollicis

Origin: trapezium

Insertion: metacarpal 1

Action: opposes thumb

Innervation: median nerve

Abductor digiti minimi

Origin: pisiform

Insertion: proximal phalanx of digit 5

Action: abducts digit 5

Innervation: ulnar nerve

Flexor digiti minimi brevis

Origin: hamulus of hamate

Insertion: proximal phalanx of digit 5

Action: flexes digit 5

Innervation: ulnar nerve

opponens digiti minimi

Origin: hamulus of hamate

Insertion: metacarpal 5

Action: opposes digit 5

Innervation: ulnar nerve

extensor carpi radialis longus (posterior muscles acting on the hand)

Origin: lateral supracondylar ridge of humerus

Insertion: metacarpal 2

Action: Extends and abducts hand

Innervation: radial nerve

Extensor carpi radialis brevis

Origin: lateral epicondyle of humerus

Insertion: metacarpal 3

Action: Extends and abducts hand

Innervation:radial nerve

Extensor carpi ulnaris

Origin: lateral epicondyle of humerus, proximal ulna

Insertion: metacarpal 5

Action: Extends and adducts hand

Innervation: radial nerve

Extensor digitorum

Origin: lateral epicondyle of humerus

Insertion: middle and distal phalanges of digits 2-5

Action: extends phalanges 2-5, extends hand

Innervation: radial nerve

abductor pollicis longus

Origin: posterior radius and ulna, interosseus membrane

Insertion: metacarpal 1

Action: abducts and extends thumb, abducts hand

Innervation: radial nerve

Extensor pollicis longus and brevis

Origin: posterior radius and ulna, interosseus membrane

Insertion: proximal and distal phalanges of thumb

Action: extends thumb

Innervation: radial nerve