Anatomy - Upper body Flashcards
4 shoulder joints (creating a shoulder platform)
- Sternoclavicular: sternum and clavicle
- Scapulothoracic: scapula and thoracic (upper) spine
- Acromioclavicular: acromion and clavicle
- Glenohumeral: humerus and glenoid
2 bones of the forearm
Radius
Ulna
3 main bones types in the hand
- carpal
- metacarpal
- phalanges
Movement of the scapula
- elevation (lifting up)
- depression (pulling down)
- retraction (hugging in)
- protraction (drawing apart)
- upward rotation
- downward rotation
Movement of the shoulder
- flexion (linear lifting up)
- extension (linear drawing back)
- horizontal flexion (arms across toward body)
- horizontal extension (arms wide away)
- abduction (arm away from midline)
- adduction (arm towards midline)
- lateral (external) rotation
- medial (internal) rotation
- circumduction (rotation)
Yoga & shoulders
Correct muscular activation is key, especially when weight bearing.
3 main bones of the shoulder
- humerus: upper arm bone
- clavicle: collarbone
- scapula: shoulderblade
Main muscles at elbow joint
- biceps
- triceps
Biceps
- crosses over shoulder & elbow joint
- flexes the forearm
- assists with shoulder flexion (linear lifting up)
Triceps
- originates from the scapula
- extends the arm at elbow joint
- assists with arm adduction from shoulder joint
- stabilizes elbow in finer movements of the hand (like writing)
Movements at elbow joint
Hinge joint:
- flexion
- extension
Radius & ulna relationship:
- supination: palm facing toward the body (parallel)
- pronation: palm facing away from the body (crossing)
Movements at wrist joint
Ellipsoid joint:
- extension & flexion
- adduction & abduction
Carpal tunnel syndrome
- compression of the nerves
- pain, tingling, numbness
Movements of the fingers
- extension & flexion
- adduction & abduction
Fingers have enormous mobility.
Thumb contributes to the hands versatility.
Equipped with a complex system of tendons.
Function of the rotator cuff muscles
Important for stability and movement of the shoulder
4 rotator cuff muscles
- Supraspinatus: abduction (lifts arm sideways)
- Infraspinatus: external rotation (rotates arm outwards)
- Teres Minor: external rotation (rotates arm outwards)
- Subscapularis: internal rotation (rotates arm inwards, draws humerus bone down and in)
Rhomboids
- 2 part muscle: rhomboid minor and major
- retraction: draws scapula towards midline, opens the chest
- lifts and rotates scapula
Key shoulder muscle to engage in chaturanga
Rhomboids & serratus anterior
Serratus anterior
- multi headed muscle
- protraction: draws scapula away from midline
- prevents the scapula from lifting or winging
Deltoids
- 3 part muscle: anterior, lateral/medial, posterior
- prime mover in abduction of arm
- assists with flexion and extension at shoulder joint
Levator scapulae
- elevates the scapula
Trapezius
- 3 part muscle: superior, middle, inferior
- postural and active movement muscle
- elevates, depresses, rotates and retracts the scapula
- tilts and turns the head and neck
Pectoralis
- 2 parts: major & minor
- adducts & internally rotates the arm, flexes the arm & depresses the shoulder
Common shoulder injuries in yoga
- inflammation or pain in the shoulder muscles / surrounding tissues
- repetitive motion injuries
- dislocations
- bursitis / impingement inside the joint
- frozen shoulder
- to deep or forceful adjustments
How to keep the shoulders healthy in yoga
- tadasana alignment: shoulders externally rotated
- awareness of the muscles that keep shoulders back and chest open
- build chaturanga strength slowly
- sequencing to balance out the lifting / pressing actions of the shoulders
Key feature of shoulders in general
Most mobile joint, designed to lift, press away, hang, move, climb.
And therefore crucial to build stability.
