Anatomy 1 Midterm (shoulder, arm, hand)

How many muscles are in the rotator cuff

4

What are the 4 rotator cuff muscles

Supraspinatus, Infraspinatus, Teres minor, subscapularis

Supraspinatus (rotator cuff)

O: supraspinous fossa of scapula

I: superior facet of the greater tubercle on humerus

Infraspinatus (rotator cuff)

O: infraspinous fossa of scapula

I: middle facet of greater tubercle on humerus

-lateral rotation of humerus

Teres minor (rotator cuff)

O: Middle part of lateral border of scapula

I: inferior facet of greater tubercle on humerus

-laterally rotates humerus

Subscapularis (rotator cuff)

O: subscapular fossa of scapula

I: lesser tubercle of humerus

-medially rotates humerus

Teres major

O: posterior surface of inferior angle of scapula

I: medial to intertubicular groove of humerus

-adducts humerus

Deltoid

Origin: lateral third clavicle acromion and scapula spine

Insertion: deltoid tuberosity on humerus

-functions the glenohumeral joint

-Flexes and medially rotates humerus

-abducts humerus

 

Rhomboid major and minor

Origin: spinous process of some virtebrae near the neck (c7-t5)

Insertion: medial border of scapula

Actions: elevates scapula, retracts scapula, downward rotates scapula

Major: inferior aspect

Minor: superior aspect

Levator scapula

Origin: transverse process of the vertebrae c1-c4

Insertion: superior medial border of scapula

Actions: elevates scapula, downwards rotates scapula

Latissimus dorsi

Origin: spinous process of thoracic vertebrae, fascia, iliac crest and inferior 3-4 ribs

Insertion: intertubercular groove of humerus

-powerful extender allows for extension all the way back

-inserts under armpit

-extends humerus, adducts humerus, medially rotates humerus

-downward rotates scapula

 

Trapezius

Origin: external occipital protuberance, nuchal ligament to c7-t-12 spinous process

Insertion: lateral 1/3 of clavicle acromion and scapula spine

Actions:

Descending fibers, elevates scapula

Middle or all fibers, retracts scapula

Ascending fibers, depresses scapula

Serratus anterior

Origin: 1^st –8^th rib

Insertion: anterior surface of the scapula’s medial border

Actions: Protracts scapula, upwards rotates scapula, depresses scapula

Subclavius

Origin: 1^st rib

Insertion: inferior surface of clavicle

Actions: depresses the clavicle 

Pectoralis minor

Origin: 3^rd to 5^th ribs

Insertion: coracoid process

Actions: depresses the scapula, protract the scapula, downward rotates scapula

-Only helps other muscles moving its main function

 -deep to pec major

Pectoralis major

superficial

-two heads (clavicular, sternocostal)

Clavicular: contracts to help arm flextion

Sternocostal: when it contracts it will pull your arm down (doesn’t allow full extension)

-Strong adductor

-protracts and depresses scapula

Origin: Clavicular head

Insertion: lateral to intertubercular groove of humerus

what is a facet

A facet in anatomy refers to a small, smooth surface on a bone that forms a joint with another bone. It allows for movement and articulation between bones. Facets are commonly found in the vertebrae of the spine, where they contribute to the flexibility and stability of the spinal column.

Antagonist 

-opposes action of another muscle 

-prime mover concentrically contracts, antagonist opposes by contraction eccentrically 

synergist

-muscle that helps the prime mover 

Fixator 

-steadies proximal part of limb through isometric contraction while movement occurs in distal parts 

Prime mover (agonist) 

Main muscle working to produce movement  

Isometric contraction

-muscle length remains the same  

-no movement occurs  

 

Tonic contraction (tonus) 

-doesn’t move  

-gives firmness and assists with posture and stability 

-keeps muscle ready to respond  

 

Reflexive contraction 

-automatic contractions  

Ex. Diaphragm for breathing 

Contraction 

-muscles can only pull when they contract 

-generally, one end of the muscle does not move during contraction 

-origins (proximal) 

-insertions(distal) 

Circular or sphincteric 

-muscles that wrap around your eye 

-when shortened the eye closes 

 

Convergent muscle 

-allows for larger cross-sectional area 

-produces more force

Pennate muscles  

-feather likes in look 

-multipennate (fibers go in different directions) 

What makes a muscle 

-reddish portion of muscle called contractile  

-white non contractable portion (tendon) 

-length of the muscle (two tendons and contractile) 

-tendon attaches muscle to bone 

 

Smooth muscle 

-no striations 

-pushes food through digestive system 

-involuntary 

Cardiac straited 

-specific muscle in heart 

-involuntary 

-primary in the heart and aorta  

Skeletal straited  

-voluntary muscles 

-makes up most of the muscle in the body 

Glenohumeral joint 

Ball and socket joint (very mobile but unstable) 

Ring around the joint is labrum of specific joint  

Joint capsule and bursa  

allows for flexion extension abduction adduction and external and internal rotation

SC joint or sc ligament 

Saddle but functions as a ball and socket  

60 degrees of movement in the frontal view  

25-30 degrees in transverse plane undergoing contraction and retraction  

AC joint or ac ligament 

Plane type synovial joint  

2-3cm from lateral part of acromion  

 

Condyle

Large articulating surface

Epicondyle

Superior to condyle

muscles and ligaments come from/attach to

creates a hinge

what is a saddle joint

synovial joint in the human body formed by two bones with concave and convex surfaces. It allows movement in two planes and provides flexibility and stability. An example is the joint between the thumb and wrist.

Crest

Ridge of a bone with rough surfaces allowing muscles and connective tissue to attach  

what is a plane joint

a type of synovial joint in the human body. It allows bones to slide or glide past each other in a flat plane of motion. This joint provides limited movement in multiple directions, such as side-to-side or back-and-forth movements. Examples of plane joints include the joints between the carpal bones in the wrist and the tarsal bones in the ankle.

what is a hinge joint

A hinge joint is a type of synovial joint that allows movement in only one plane, like a door hinge. It enables flexion and extension movements, such as bending and straightening, and is found in joints like the elbow and knee.

what is a ball and socket joint

A ball and socket joint is a type of synovial joint in which the rounded end of one bone fits into the cup-like socket of another bone. This type of joint allows for a wide range of motion in multiple directions. Examples of ball and socket joints in the human body include the hip and shoulder joints.

what is a pivot joint

A pivot joint is a type of synovial joint that allows rotational movement. It consists of a rounded or cylindrical bone that rotates within a ring formed by another bone and a ligament. The movement at a pivot joint is limited to rotation around a central axis. An example of a pivot joint is the joint between the first and second vertebrae of the neck, which allows the head to rotate from side to side.

what are the 5 types of bones

long bones, short bones, flat bones, irregular bones, and sesamoid bones.

example of a long bone

The femur (thigh bone) is an example of a long bone.

example of a short bone

The carpal bones in the wrist are an example of short bones.

example of flat bone

The scapula (shoulder blade) is an example of a flat bone.

example of irregular bone

An example of an irregular bone is the vertebrae in the spine.

example of sesamoid bone

The patella (kneecap) is an example of a sesamoid bone.

what is a foramen

a bone opening that allows nerves, blood vessels, and other structures to pass through. enabling communication and transportation within the body.

what is fossa

hollow or depressed area

Trochanter

Large blunt elevation of bone

trochlea

Spool-like articular process that acts as a pully

Tubercle

small raised eminence

Greater: lateral

Lesser: medial

What makes a muscle

-reddish portion called a contractile

-white non contractable portion (tendon) 

-length of the muscle (two tendons and contractile) 

-tendon attaches muscle to bone

Convergent muscle 

-allows for larger cross-sectional area 

-produces more force 

 

Bursa & sheathes 

-reduces friction 

-surrounds tendons  

 

What are the 3 main approaches to anatomy

^{regional, systemic, and clinical} 

regional anatomy

1. ^{Organizes body as major segments} 

2. ^{Main body (Head, neck, thorax, back, abdomen, pelvis, lower limb, upper limb)} 

3. ^{Further broken down into parts, areas and reigon ex. (part-head area-face reigon-eye reigon)} 

systemic anatomy

Breaks the body up into systems Ex. Nervous system

clinical anatomy

^{Trying to look at anatomy in a clinical setting. Ex. (how would the absence of a certain muscle activity manifest, instead of asking “what does this muscle do”)} 

Median plane

Flat plane that goes the entire length of your body, divides body to left and right 

Sagittal Plane

Divides the body in half vertically (doesnt have to be in the middle)

Frontal (coronal) plane 

Divides body into anterior and posterior (front and back parts) 

Transverse plane 

• Horizontal for entire body except for feet 

• Divides body into superior (upper) and inferior (lower part) 

 

Longitudinal sections  

180 degrees of longitudinal sections 

Transverse sections 

-90 degrees to longitudinal axis 

Oblique sections 

-not cut along pervious planes 

-non right angles 

Palmer

surface of the hand in anatomical position (palm of hand)

Dorsal

posterior part of hand in anatomical position (back of hand)

Planter

planter surface of the foot (bottom of the foot) 

Dorsal

superior surface of the foot (top of foot) 

Bilateral

structures that exist on both sides ex. Eye, ear 

Unilateral

structure only exists on one side ex. Spleen  

Ipsilateral

something occurring on the same side of the body as another structure 

Contralateral

occurring on opposite side relative to another structure 

How many types of joints are there

6

what are the 6 different types of joints

plane, hinge, saddle, condyloid, ball and socket, pivot

flexion

decreasing the angle between bones

extension

increasing the angle between bones

Forearm

Pivot joint (pronation, supination) 

-ulna and radius 

 

Elbow

-hinge joint (flex extend) 

-humerus 

Wrist

-8 carpal bones  

-flexion extension and ab/adducting  

Bursae

- reduce friction to lower chances of inflammation 

 

Ulnar collateral ligament 

-multiple ligaments atatched on the posterior aspect of the ulna  

Carrying angles

Male carrying angle:10-15 degrees 

Female carrying angle: greater then 15 degrees  

Ulna

-flexion and extension only 

-lateral in anatomical posistion  

 

Radius

-supination and pronation 

-ulna does not move while this occurs  

 

Carpal bones

So- Scaphoid 

Long- Lunate 

To- Triquetrum 

Pinky- Pisiform 

Here- Hook of hamate 

Comes- Capitate 

The- Trapezoid 

Thumb- Trapezium

Ulnar collateral ligament

-ulnar styloid process to pisiform and triquetrum 

Digits 2-5 hinge joints (collateral ligaments) 

Hand Joints

Thumb- saddle joint 

4 other digits ellipsoidal joint 

Deep transverse metacarpal ligament 

-provides structure to the hand 

-decreases movement  

Annular ligament  

-pivot joint 

Short head of biceps 

Short head of biceps 

O: Coracoid process of scapula 

I: Radial tuberosity and bicipital aponeurosis 

Long head of the bicep 

O: Supraglenoid tubercle of scapula 

I: radial tuberosity 

Coracobrachialis

O: Coracoid process 

I: middle medial aspect of humerus 

-Flexes arm (shoulder) 

-adducts arm (shoulder) 

 

Brachialis 

O: distal half of anterior humerus 

I: Coracoid process (ulna) 

-flexes forearm (elbow) at all posistions  

 

Triceps brachii 

O: long head: infraglenoid tubercle 

O: lateral head: posterior surface of humerus 

O: Medial head: posterior surface of humerus 

I: Olecranon of ulna 

-Extends forearm (elbow) 

-long head adducts shoulder  

 

Anconeus 

O: lateral epicondyle of humerus 

I: olecranon and posterior surface of ulna 

-extends forearm (elbow)

how many muscles are assosiated with the forearm

19