Upper limb - Shoulder + back Flashcards
What forms the anterior wall of the Axilla?
Pectoralis Major + Minor
What forms the posterior wall of the axilla?
Latissmus Dorsi + teres Major
What forms the medial wall of the axilla?
Thoracic wall
Serratus anterior
What forms the lateral wall of the axilla?
Intertubular groove of humerus
What are the contents of the axilla?
Axillary artery/nerve
Axillary lymph nodes
Brachial plexus
Biceps Brachi
At what anatomical point does the axillary artery begin?
Lateral margin of 1st rib
At what anatomical point does the brachial artery begin?
Lower margin of teres major
What nerve roots constitute the Brachial plexus?
C5-T1
What nerve roots form the upper trunk of the brachial plexus?
C5-6
What nerve roots form the middle trunk of the brachial plexus?
C7
What nerve roots form the lower trunk of the brachial plexus?
C8-T1
What is Erb’s point?
Erb’s point is the convergance of C5+C6 when the form the upper trunk
If damaged this can cause Erb’s palsy
What is Erb’s palsy?
Injury to the upper trunk of brachial plexus
Results in “waiters tip” of upper limb
Arm is medially rotated, wrist flexed
What muscles are affected in Erb’s palsy
Deltoid
Wrist extensors
Elbow flexors
What can cause Erb’s palsy?
Hyperextension of head form shoulder
I.e Fall on shoulder, birth injury or iatrogenic
What is Klumpke’s palsy?
Injry to the lower trunk of the brachial plexus
Affects intrinisc muscles of hand and ulnar flexors of wrist and fingers
What causes klumpkes palsy?
Hyper abduction of the arm
What are the cords od hw brachial plexus?
Lateral
Medial
Posterior
What are the branches of the lateral cord of the brachial plexus?
Lateral pectoral nerve
Median nerve (lateral root)
Musculocutaneous nerve
What are the bracnhes of the medial cord of the brachial plecus?
Medial pectoral nerve (C8-T1)
Medial cutaneous nerve of arm (T1)
Medial cutaneous nerve of forearm (C8-T1)
Ulnar nerve
What are the branches of the posterior cord of the brachial plexus?
Thoracodorsal
Axillary nerve
Radial nerve
Subscapular nerve
What does the lateral pectoral nerve supply?
Pectoralis major
What does the medial pectoral nerve supply?
Pectoralis muscles
What does the thoracodorsal nerve suply?
Latissimus dorsi
What does teh subscapular nerve supply?
Teres major
Supsacpularis
What is the sensory value + nerve of the badge area?
Axillary nerve - C5/6
What are the different axillary lymph nodes?
Pectoral group Subscapular group Apical group Central group Lateral group
Where does the upper limb + pectoral girdle articulate ?
Sternocalvicular joint
What type of bone is the clavicle?
A long bone
What muscles attach to the shaft of the clavicle?
Deltoid Trapezius Subclavius Pectoralis major Sternocleidmastoid Sternohyoid
What is the weakest segment of the clavicle?
Medial + lateral 1/3s
What does the scapula articulate with?
Humerus
Clavicle
Lesser extent, ribs
What type of joint is the sternoclavicular joint?
Shallow saddle (synovial)
What type of joint is the acromioclavicular joint?
Synovial plane
What type of joint is the glenohumeral joint?
Synovial ball and socket
What is scapulo-humeral rhythm
The 2:1 ration of: 2 degrees occurring at the Shoulder (Glenohumeral) Joint 1 degree occurring at the Scapulo-Thoracic joint
What is the scapulothoracic joint?
It is not a true joint, but has movement around a joint axis
What muscles cause elevation of the scapula (shrugging)
Levator scapulae
Trapezius (upper fibres)
Serratus anterior
What muscles cause depression of the scapula?
Pectoralis minor
Trapezius (inferior fibres)
Latissimus dorsi
What muscles cause protraction of the scapulae (forward movement like punching/pushing)
Serratus anterior
Pectoralis minor