Exam 2 material Muscles kinesology

Atlas + bony markings

C1, has a larger articulating surface superiorly to meet with the skull, facet for the dens (C2) to articulate,

C2 Axis + Bony markings

Vertical process on the superior side (DENS) to extend and articulate with C1, lets C1 to spin on top of C2

Joints of CS-atlanto occiptial joint-

atlanto occipital joint- skull and atlas

headflexion and extension (think double chin, head motion, not great range)

Joints of CS- AtlantoAxial

atlas and axis articulate with the dens, cervical rotation, pivot joint

Joints of the CS- Facet joints

between the transverse processes, C2-C7, the rest of the spinal column, functional=diarthrodial, structural=synovial, gliding joints with minimal movement, built for stability and not for mobility

motions: flexion/extension, lateral bending, rotation

Lordosis vs Kyphosis

Lordosis is the convex anterior in middle curvature in C spine, important for force distribution and shock absorption

Kyphosis is what causes the thoracic spine to bend outward, producing a rounded or “hunchback” appearance.

Fibrocartilage discs

joint type- amphidiplrodal, think jelly donut analogy

contains an outer layer=annulus, center jelly layer= nucleus pulposus; layers are important for shock absorption

CS: neuromuscular

The spinal cord goes through foramen in each vertabrae; the nerve root runs through the intervertebral foramen and decreases in size as it branches, sending/receiving sensory and motor information.

CS Muscles: SCM- O, I, action

sternocleidomastoid

originates at the sternum/clavicle

inserts at the mastoid process

actions: head extension/ cervical flexion

Ipsilateral lateral bending

contralateral rotation

elevation of sternum with deep inspiration

CS MUSCLES: Scalene

Anterior: Originates C3-6

Insertion on 1st rib

actions= neck flexion/lateral bending

Middle: Originates C1/2-7

Insertion on 1st rib

Actions = neck lateral bending and first rib elevation

Posterior: Originates at the C4-6/ C5-7

Insertion on the second rib

Actions: 2nd rib elevation

Splenius (Cervicis and capitus combinded)

On the posterior CS/TS

Originates from C7-T6
at the occipital bone, mastoid process and C1-C3

actions Head/cervical extension

ipsilateral lateral bending and rotation

Levator Scapulae

Originates at the C1-C4

Insertion at the medial border of the scapula on the superior angle for scapular elevation

Thoracic spine bones- Vertebrae

12 vertebrae, no transverse foramin, have a costal facet to articulate with the ribs

Thoracic spine bones: Ribs

12 pairs for the 12 thoracic vertebrae

True ribs (1- 7)- protect and support the internal organs like the heart and lungs and are directly supported by the sternum

False Ribs (8-10) Protect of organs like the spleen and stomach

Floating ribs (11-12) guard organs like kidneys, are not connected all the way around

Thoracic spine JOINTS- Facet Joints

Joints between the vertebrae, T1-12, these ‘synch’ with C7 and L1, these are Diarthrodial Synovial Gliding joints

Actions: Flexion and extension, lateral bending and rotation

Thoracic spine JOINTS- Costovertebral

joint between the ribs and vertebrae, Diarthrodial synovial gliding joints that can flex and extend

Thoracic spine JOINTS-Sternoclavicular

Joint between the sternumn and clavicle

diarthrodial synovial gliding joint, protraction and retraction @15*, Elevation @45* and depression @15*

Thoracic spine JOINTS- Acromioclavicular

AKA AC joint, Between the acromion process and the clavicle, diarthrodial synovial gliding, can perform gliding and slight rotation as needed with shoulder movement

Thoracic spine JOINTS- Coracoclavicular

between the coracoid process and the clavicle, a diarthrodial synovial gliding joint, disperses load and stabilizes as needed with shoulder movement

Thoracic spine JOINTS- Scapulothoracic

Between the scapula and the ribcage (thoracic spine)

False diarthrodial joints, glides for protraction/retraction, elevation/depression, upward rotation/downward rotation

Erector Spinae

Origin= lumbar inferior thoracic aponeurosis (thick band of CT instead of aponeurosis

insertion (3 parts)

Spinalis= superior thoracic

Longissimus = C2-6 Mastoid process

Iliocostalis= Ribs

Actions= spine extension, lateral bending of spine this is specific to the area of pull

Serratus anterior

Orgin-Posterior Lateral Aspect Ribs 1-9

Insertion= Medial Border of Scapula

Actions= scapular stabilozer, protraction of scapula, upward rotation of scapula, (winging scapula applied, why would a weak serratus anterior cause winging scapula?

Internal vs external intercostals

internal intercostals depress the ribs for exhalation, squeezing out excess air

External intercostals elevate the ribs for inhalation they elevate ribs

Pectoralis Major

Origin on clavicle and sternum, plus costal cartilage

Insertion on the lateral humerus

actions

adduction and IR of humerus

flexion, adduction when <90, abduction when >90*

Pectoralis Minor

Origin - Ribs 3-5

Insertion - Coracoid Process

Action - Scapular stabilization, protraction, downward rotation, depression

Trapezius

Origin: C7- T12, skull (occipital)

Insertion: spine of scapula, acromion, clavicle

Actions- lateral bend and extension of the head, elevate the scapula

Upper trap: scapular elevation/extension/rotation of head

middle fibers elevate and retract scapula

lower fibers depress and retract the scapula

Rhomboids

Origin- C7-T5

Insertion- medial border of scapula

Actions- all scapular

Retraction, elevation w/ retraction, downward rotation from upwardly rotated position

Latissimus Dorsi

Origin= T7-L5, Iliac crest, and sacrum

Insertion= Medial humerus

Actions- adduct, extend IR arm, stabilize, and rotate trunk

bones of shoulder girdle

Clavicle (anterior/superior)

Scapula (posterior and superior)

Ribs (medial)

Sternum (rib stability and muscle attachment)

what is the ratio of the scapulohumeral rhythm

1 part scapulothoracic

2 part GH

180 of shoulder abd =120 glenohumeral+60 scapular

Arthrokinematics of the scapula- Lateral Tilt

Protraction

Arthrokinematics of the scapula- Medial Tilt

Retraction

Arthrokinematics of the scapula- extension

anterior tilt

Arthrokinematics of the scapula- flexion

posterior tilt

GH muscles Actions- Latissimus Dorsi

Humeral Adduction, humeral extension, humeral IR, humeral Horizontal abduction

GH muscles Actions- Deltoid

Anterior- GH Abduction, flexion, internal rotation, horizontal adduction

Middle- GH abduction

Posterior- GH Abduction, extension, extenral rotation, horizontal abduction

GH muscles - Coracobrachialsis

Origin- Coracoid process of the scapula

Insertion- middle of the border of the humeral shaft

actions - GH Flexion, GH Horizontal Adduction, GH Adduction

GH muscles Actions- Teres Majoir

GH Adduction, GH Extension, GH Internal Rotation

Rotator Cuff Muscles - Supraspinatus

Orgin- Supraspinatus fossa, superior posterior scapula

insertion- greater tubercle of humerus

Actions- GH Abduction, main agonist first 0-15 degrees of abduction, GH stabilization

Rotator Cuff Muscles- Infraspinatus

Origin- posterior medial scapula medial border

Insertion- posterior lateral humerus, greater tubercle

Actions- GH Horizontal abduction, GH ER, GH stabilization

Rotator Cuff Muscles- Teres Minor

Orgin- Posterior Scapula lateral boarder

Insertion- Posterior Lateral Humerus Greater Tubercle

Actions- GH ER, GH Addiction, GH stabilization

Rotator Cuff Muscles- Subscapularis

ORgin- Subscapular fossa anterior scapula, medial boarder

Insertion- Lesser tubercle of the Humerus

Actions- GH IR, GH Adduction, GH Stabilizaiton- Arm raised pulls arm forward and down, scapular neuromuscular control

elbow bones

Humerus, ulna, radius

what are the two elbow joints

both diarthrodial synovial joints

Humeroulnar- medial

radiohumeral- lateral more joint space, less bone on bone more soft tissue provides more mobility

HINGE JOINTS PROVIDIN ELBOW FLEXION AND EXTENTION

Forearm Syndesmosis

interosseous membrane between the ulna and radius, diarthrodial synovial pivot joint, the radius pivots on the ulna for pronation and supination, some stability some moibility

Elbow ligaments- extension

bone on bone locking olecranon process in the fossa, CLOSED PACKED POSITION, less mobile more stable

Elbow flexion

Less stabile more mobile, Ligament support for force transmission/mobility

Ulnar collateral ligament (medial) connects the ulna and humerus in 3 parts, protects from valgus stress (outside in) esp in overhead elbow ext.

Radial Collateral ligament- connects the radius and humerus protect from varus stress- middle out, helps prevent excess lateral rotational instability

Annular Ligament

goes around the head of ligament, hugs radius to the ulna

Elbow muscles- Bicep Brachii

Long- Origin- supra glenoid tubercle- labrum, Insertion- Radial Tuberosity

Short- Origin- Coracoid Process Insertion- Bicep Aponeurosis

Action- Humeroulnar flexion, radioulnar supination, weak GH flexion (elbow flexion)

Elbow Muscles- Brachialis

Origin- Distal Anterior humerus

Insertion- Coracoid Process of Ulna

Actions summarized- Humeroulnar flexion (reverse grip curls)