1. UPPER LIMB What is a limb? Skeleton Joints Shoulder/Scapula muscles
Brachial plexus—getting spinal nerves out onto limb
Muscles—anterior and posterior compartments
Sensory innervation
Surface anatomy
From Royal Collection da Vinci drawings
Frolich, Human Anatomy,UpprLimb

2. What is a limb? Ventral somatic outgrowth of outer tube
Bones (made of bony tissue, cartilage, and other tissues)
Joints
Muscles
Nerves (with motor neurons to muscles, sensory neurons to skin, proprioceptors)
No viscera--all innervation is somatic (motor or sensory) from ventral ramus of spinal nerve (except autonomics to blood vessels)
Frolich, Human Anatomy,UpprLimb

3. Upper Limb Skeleton Scapula Humerus Radius, ulna
Carpals--proximal, distal
Digits
Metacarpals
Phalanges
Frolich, Human Anatomy,UpprLimb

4. Joints
Frolich, Human Anatomy,UpprLimb

5. Frolich, Human Anatomy,UpprLimb

6. Muscle origins and insertions
Muscle crosses joint
Origin is usually proximal and insertion is usually distal
Origin is considered fixed in analyzing muscle action
Muscle action (concentric) is given by movement of insertion relative to origin across joint
Remember:
Sometimes insertion might be fixed
Muscle may be active isometrically and concentrically giving different real function during real activity
Frolich, Human Anatomy,UpprLimb

7. Muscles of Scapula If INSERTION on scapula, muscle moves scapula
Trapezius
Rhomboids
Pectoralis Minor
Serratus Ventralis
Levator Scapulae
If ORIGIN on scapula, muscle moves arm
Teres Major
Latissimus Dorsi (partially on scapula)
Frolich, Human Anatomy,UpprLimb

8. Rotator Cuff Muscles originate on fossae of scapula
Supraspinatus
Infraspinatus
Teres minor
Subscapularis
Muscles originate on fossae of scapula
Help support “open socket” of shoulder joint
Insert around ball of femur
Medial and lateral rotation of upper limb
Typical baseball pitcher injury
Frolich, Human Anatomy,UpprLimb

9. Axilla = Armpit Region between arm and chest Boundaries Contents
Ventral - pectoral muscles
Dorsal = latissimus dorsi, teres major subscapularis
Medial = serratus ventralis
Lateral = bicipital groove of humerus
Contents
Axillary nerves and blood vessels
Axillary lymph nodes
And….the……Brachial plexus
Frolich, Human Anatomy,UpprLimb

10. Frolich, Human Anatomy,UpprLimb

11. Brachial Plexus Posterior Compartment—posterior cord
Anterior compartment—medial, lateral cords
Name of cord is relative to axillary artery
Frolich, Human Anatomy,UpprLimb

12. Brachial plexus organizes nerves out to muscles of upper limb
One posterior nerve
Radial n.
Three anterior nerves
Musculocutaneous n.
Median n.
Ulnar n.
Frolich, Human Anatomy,UpprLimb

13. Muscles and nerves by compartment
Frolich, Human Anatomy,UpprLimb

14. POSTERIOR AND ANTERIOR COMPARTMENTS
Frolich, Human Anatomy,UpprLimb

15. Biceps—anterior compartment, flexion (M-C n.)
Triceps—posterior compartment, extension (radial n.)
Frolich, Human Anatomy,UpprLimb

16. Anterior Compartment Forearm--flexors
Medial Epicondyle
Brachioradialis
Pronator Teres
Flexor Carpi Radialis
Flexor Carpi Ulnaris
Flexor Retinaculum
Flexor Digitorum Superficialis is deep to other flexors
Anterior View
Frolich, Human Anatomy,UpprLimb

17. Posterior Compartment of Forearm--extensors
Lateral Epicondyle
Brachioradialis
Extensor digitorum
Ext Carpi Radialis Longus
Extensor carpi ulnaris
Posterior View
Frolich, Human Anatomy,UpprLimb

18. Muscles (radial nerve)
ANTERIOR MUSCLES
M-C nerve
Biceps
brachialis
Median nerve
Forearm flexors
Thumb intrinsics (1M$ nerve)
Ulnar nerve
Flexor carpi ulnaris
Hand intrinsics
POSTERIOR MUSCLES
Muscles (radial nerve)
Triceps
Anconeus
Brachioradialis
Carpal, digit extensors
Frolich, Human Anatomy,UpprLimb

19. Sensory from limb (dermatomes/sensory skin segments from spine)
Dermatomes extend over limbs
Twisted orientation reflects twisting of limb during development
Named nerves generally innervate skin over muscles that they innervate
Frolich, Human Anatomy,UpprLimb

20. Sensory territory of nerves
REMEMBER: Brachial plexus re-directs spinal routes into named nerves covering certain territory
Cutaneous branches of medial cord/ulnar nerve
Frolich, Human Anatomy,UpprLimb

21. Routes of nerves (in human)
M-C: between biceps brachii and brachialis
Median: medial/posterior to biceps, branches into forearm flexors at elbow then to hand through carpal tunnel
Recurrent median (1M$) superficial at wrist to thumb over thenar emminence) deficit - ape’s hand
Ulnar: medial in arm, posterior to medial epicondle of humerus (funny bone) down medial forearm medial to carpal tunnel into palm
Radial: deep posterior arm around lateral epicondyle of humerus to forearm (deep and superficial branches)
Frolich, Human Anatomy,UpprLimb

22. Musculocutaneous Nerve UlnarArtery
Median Nerve
Ulnar Nerve
Brachial Artery
Musculocutaneous Nerve
UlnarArtery
Where’s Radial Nerve?
Radial Artery
Median Nerve
Ulnar Nerve
Frolich, Human Anatomy,UpprLimb

23. Surface Anatomy of Upper Limb
Biceps + Triceps brachii
Olecranon Process
Medial Epicondyle
Cubital Fossa
Anterior surface elbow
Contents
Brachial Artery
Median Nerve
Boundaries
Medial = Pronator teres
Lateral = Brachioradialis
Superior = Line between epicondyles
Frolich, Human Anatomy,UpprLimb

24. Surface Anatomy of Upper Limb
Carpal Tunnel
Carpals concave anteriorly
Carpal ligament covers it
Contains: long tendons, Median nerve
Inflammation of tendons = compression of Median nerve
Anatomical Snuffbox
Lateral = E.pollicis brevis
Medial = E. pollicis longus
Floor = scaphoid, styloid of radius
Contains Radial Artery (pulse)
Surface Anatomy of Upper Limb
Frolich, Human Anatomy,UpprLimb

25. Suggestion: a muscle table organized by. Joint crossed
Suggestion: a muscle table organized by Joint crossed? Nerve innervating? Action? Compartments? All of the above?
Frolich, Human Anatomy,UpprLimb

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