Download Lecture 16: Wrist and Hand

Lecture 9: Pectoral and Axilla Anatomy (Dr. Blanck)
Superficial Thorax and Thoracoappendicular Muscles
 Deltopectoral Triangle
o Boundries:
 Superior – clavicle
 Lateral: anterior deltoid muscle
 Medial: clavicular head of pec major m.
o Cephalic vein  axillary vein
 Pectoralis Major Muscle
o Forms anterior wall of axilla
o 2 heads: clavicular, sternocostal
o actions on humerus: adduction, medially rotate
o innervation: lateral pectoral nerve, medial pectoral nerve
 Pectoralis Minor Muscle
o Attaches to coracoid process and ribs 3-5
o Actions: stabilize scapula, elevating ribs (deep inspiration)
o Medial pectoral nerve
 Subclavius Muscle:
o protection to subclavian vessels and brachial plexus
o anchors and depresses clavicle, stabalize SC joint
 serratus anterior m.
o forms medial wall of axilla
o “sawtooth appearance”
o holds scapula against body wall, protracts scapula, scapular upward rotation
o Long thoracic nerve
o Winged scapula: damage to long thoracic nerve or weakness in serratus santerior m.
Axilla
 Boundries
o Apex: Cervico-axillary canal (1st rib, clavicle, sperior scapula)
o Base: skin, fat, deep fascia
o Anterior wall: Pec major and minor
o Posterior wall: scapula, subscapularis, lat. Dorsi, teres major mm
o Medial wall: thoracic wall (ribs 1-4)
o Lateral wall: intertubercle groove
 Contents
 Axillary a.,/ v, /l.n/ Brachial plexus, axillary fat
Lecture 11: Brachial Plexus
Brachial Plexus
 C5-T1 ventral rami
 Intimate relationship between cords and axillary artery
 Innervation to pectoral region, scapular region, and upper extremity
 Can be pre-fixed or post-fixed
 Randy Travis Drinks Cold Beer
 Roots: ventral rami C5-T1
 Trunks:
o Upper: C5 and C6
o Middle: C7
o Lower: C8 and Ti
 Divisions: each trunkanterior and posterior divisions
 All 3 posterior come together
 Cords
o Lateral: anterior divsions of Upper and Middle trunks
o Posterior: posterior divisions of all 3 trunks
o Medial: anterior divisions of lower trunk alone
o **cords named relative to their position to the axillary artery
 Branches off roots
o Dorsal Scapular Nerve
o Long Thoracic Nerve serratus anterior m
o Phrenic Nerve
 Branches off Upper Trunk:
o Suprascpaular nerve  supraspinatus
o Nerve to subclavius (don’t move clavicle too often(
 No branches on divisions!!
 Branches off Lateral Cord (2 LM)
o Lateral Pectoral Nerve  Pec Major
o Lateral head of median nerve
o Musculocutaneous
 Branches off medial cord (4MU)
o Medial Pectoral Nerve
o Medial Brachial cutaneous nerve
o Medial head of median nerve
o Medial antebrachium cutaneous nerve
o Ulnar Nerve
 Branches off posteror cord (STARS)
o Upper subscapular Nerve
o Thoracodorsal Nerve (middle scapular nerve)
o Axillary Nerve
o Radial Nerve
o Lower subscapular nerve  subscapularis, teres major
Brachial Plexus Injuries
 Erb’s (Erb-Duchenne) palsy: waiters tip syndrome
o Axillary, Musculocutaneous and suprascapular nerves most affected
o Arm: adducted, metiall rotated, extended, forearm in pronation
o Excessive separation of neck and hsoulder (C5 and C6 roots, upper trunk trauma)
 Posterior Cord Injury
o Flexion of arm, forearm, wrist, MP joints, thumb
o “wrist drop”
o Incorrect use to crutches
o “Saturday night palsy”: radial nerve (cut off blood supply to bone)loss of
extensors
 Klumpke’s Palsy
o Forceful upward pull of shoulder (C8 and T1 roots)
o Ulnar nerve most affected
o Loss of wrist flexion and intrinsic hand muscles
o “Claw hand”, “hand of benediction”
Anatomy Lecture 12: Upper Limb Brachium
Fractures of the Humerus: what nerve will get damaged?
 Upper end: axillary nerve
 mid-shaft: radial nerve
 lower end: ulnar nerve
Brachium:
 Anterior and posterior compartment separated by lateral and medial intramuscular septa
Anteror Compartment (Flexor)
 Coracobracialis:
o attach to coracoid process, insert midshaft of humerous (deep to short head of
biceps)
o Flexes the humerus, assists in adduction of humerus
o Musculocutaneous nerve
 Bicepts Brachii
o short head: origin at coracoid process, inserts at radial
o Long head: origin supragelenoid tubercle, inserts at bicipital aponeurosis
o Supinates forearm from neutral
o Flexes forearm at elbow (not primary flexor of elbow)
o Stabilized shoulder joint
o Weak flexor of shoulder
o Musculocutaneous nerve
 Bracialis
o Origin: lower half of anterior humerous (both intermuscular septa)
o Inserts on ulnar tuberosity, coronoid process of ulna (not to get confused w/
coracoid process of scapula)
o Primary flexor of the elbow
o Musculocutaneous nerve
Posterior Compartment (extensor)
 Triceps brachii
o **crosses 2 joints**
o Origin:

Long head: infraglenoid tubercle of the scapula
 Lateral head: upper half of humerus, and lateral intrermuscular septum
 Medial head: shaft of humerus, distal to radial groove and medial and
lateral intermuscular septum (deep to long and lateral head)
o Insertion: olecranon (ulna)
o Main and only extensor of elbow!!
 Anconeus
o Triangular, “cute”
o Origin: posterior surface of lateral epicondyle of humerus
o Inserts on lateral aspect of olectanon (ulna)
o Extends forearm at eblow
o Pulls out the elbow joint capsule during extension, prevent crushing of the capsule
by the ulna
o Radial nerve
Nerves of Brachium/Antebrachium
 Axillary: shoulder innervation
o surgical neck of humerous
o if damaged: weak abduction at shoulder joint, sensory loss, atrophy
o injury can happen during surgery
 Musculocutaneous: flexors of arm
o well protected, only likely to get injured w/ surgery
o functional loss: weak flexion at elbow joint (anterior compartment), minimal
sensory loss (because becomes cutaneous lateral antibrachial artery after it crosses
the bicepts)
 Radial: extensors of arm/forearm/wrist
o right next to humerus, can get damaged
o innervates Extensor compartments (brachium & antibrachium), sensory of forearm
and hand
o “wrist drop” can’t extend wrist at all
o fix w/ splinting (regeneration), surgery (bridge, take sural nerve from leg)
 Ulnar: intrinsic hand muscles
o Injury: claw hand, sensory loss ulnar side of hand (pinky, ring finger)
o Cubital tunnel syndrome: ulnar nerve compressed
o Guyon’s canal (tunnel) syndrome: common nerve compression, compresses ulnar
nerve as pastes though guyon’s canal (fibrous canal in flexor retinaculum)
o Symptoms: parasthesias (tingling) and anaesthesia in ring, pinky fingers
o Ulnar forearm injury: claw hand- ring and pinky extended at MCP joint, flexed at PIP
and DIP
 **Ulnar paradox: weakness of long flexors decreases claw fingers???
 Higher injury of ulnar nerve, more loss of function (but less deformity you
have)
 Median: flexors of forearm, wrist, thenar muscles
o gets damaged w/ carpel tunnel syndrome= “claw hand of first and second finger
o opposition and flexor of the thumb lost,
o sensory loss in the palm, and thumb, index, middle finger tips
Lecture 13: Upper Limb Cubital Fossa and Forearm
Cubital Fossa
 triangular space on the anterior side of the elbow
 Borders:
o Base: line connecting the humeral epidoncyles
o Medially:Pronator teres
o Laterally: Brachioradialis
 Contents:
o Radial nerve
o Bicepts brachii tendon
o Brachial artery
o Median nerve
o Median cubital vein lies in the fossa
The Elbow
Ligaments
 Annular Ligament: wraps around radial head
 Ulnar collateral Ligament: connects medial epicondyle to olectranon
o Anterior part
o Posterior part
o Transverse part
 Radial Collateral Ligament: connects lateral epicondyle to olectranon (sits above annular
ligament)
 Anterior Ligaments
 Posterior Ligaments
 Quadrate ligament: keeps radius and ulna together
 Oblique cord: piece of interosseus membrane
Anterior Forearm Muscles (Flexors)
 Superficial
o Pronator Teres
o Flexor Carpi Radialis (FCR)
o Palmaris Longus-not inside Carpal tunnel, missing in some people
o Flexor digitorum superficialis – flexes PIP joint
o Flexor carpi ulnaris
 Deep
o Flexor digitorum Profundus: flexes DIP joint
o Flexor Pollicis Longus: flexes DIP of thumb
o Pronator Quadratus: pronates forearm and hand
Innervation of Anterior Forearm
Median Nerve (think of everything on the radial side)
 Pronator Teres
 Flexor Carpi Radialis
 Palmaris Longus
 Flexor digitorum superficialis
 Lateral portion of flexor digitorum profundus (thumb, index, middle, half of ring)
Ulnar Nerve (think of everything on the ulnar side)
 Flexor carpi ulnaris
 Medial portion of flexor digitorm profundus (half of ring, pinky)
Anterior Interosseus branch of median N.
 Flexor pollicis longus


Pronator Quadratus
Flexor digitorum profundus
Lecture 16: Wrist and Hand
Carpal Bones
 Proximal row: scaphoid, lunate, triquetrum, Pisiform
 Distal row: Trapeziu, Trapzoid, Capitate, Hamate
Radiocarpal joint and carpometacarpal joints- both condyloid jointsflex/entend, ab/ad duct
Circulatory System
Brachial a.  radial and ulnar
Ulnarcommon interosseus arteryanterior and posterior interosseus branches
Ulnarsuperficial palmar arch (think umbrella forms superficial arch to keep you dry)
Radialdeep palmar arch (think raincoat is deep protection from rain)
 Palmar archescommon palmar digital arteries
Both ulnar and radial and anterior interosseus artery dorsal carpal arch
 Dorsal carpal archdorsal metacarpal arteries
The carpal tunnel
 8 tendons of the flexor digitorum (4 from FGS and 4 from FGP)
 1 tendon from flexor pollisus longus
 median nerve
 6 tunnels
o 1: abductor pollicis longus, entensor pollicis brevis
o 2. Extensor carpi radialis longus and brevis
o 3. Extensor pollicis longus
o 4. Extensor digitorum and extensor indices
o 5. Extensor digitis minimi
o 6. Extensor carpi ulnaris
 retinacula: pully to increase lever arm of tendons/muscles entering hand
o extensor and flexor
Extensors of the Wrist
 Extensor carpi radialis longus (attached at lateral supraepicondylar ridge, to 2 nd metacarpal)
 Extensor carpi radialis brevis (lateral epicondyle, attaches to 3rd metacarpal)
Extensors of the Wrist and Hand
 Extensor digitorum: (lateral epicondyle to extensor expansion of medial 4 digits)
 Extensor digiti minimi: lateral epicondyle to extensor expansion of 5 th digit)
 Supinaor (lateral epicondyle to proximal radius)
 AB-ductor pollicis longus: to 1st metacarpal
 Extensor pollicis bevis: proximal phalanx of thumb
 Extensor polices longus: distal phalanx of thumb
 Extensor Indices: to expansion of 2nd digit
Ligaments of the Hand
 Palmar aponeurosis: thick band of tendonous sheet, holds your hand together
 Transverse facicles
 Longitudinal fascicles
 Extensor Expansions
o Flattened distal portion of extensor digitorum tendons
o Attach to distal end of metacarpals, attachment point for lumbricals
**All intrinsic muscles of the hand innervated by median or ulnar nerves** (not radial)
Intrinsic Muscles of the Hand
 Thenar group: thumb muscles
o Superficial
 Flexor pollicis brevis *median n.
 Opponens pollicis *median n
o Deep Thenar Muscles
 Adductor Pollicis **Ulnar Nerve- 2nd and thir metacarpals to proximal
phalanx of thumb (think of adding more fingers)
 Works w/ CTS
 Abductor pollicis brevis *median n.
 Hypothenar group: pinky (5th digit)
o Superficial
 Flexor digiti minimi -hook of hamateproximal phalanx
o Deep
 Abductor digiti minimi -pisiform to medial base of proximal phalanx
 Opponens digiti minimi -hamate to 5th metacarpal
 Lumbricles
o 4 mucles
o Lateral 2: unipennate- **median nerve**
o Medial 2: bipennate
o Extends IP joints, flexes MP joints (lumbricals…lumbricals…lumbricals)
 Interossei: between metacarpal bones
o Dorsal Interosseous Muscles
 4 bipennate muscles
 from sides of adjacent metacarpalsextensor expansion of digits 2,3,4
 Abduct digits 2&4, stablize digit 3 (DAB-dorsal abduct)
o Palmar Interosseus Muscles
 3 muscles
 from 2nd, 4th, 5th metacarpals extensor expansions
 Adduct digits 2,4,5 to midline (PAD-palmar adduct)
LOAF: only intrinsic hand muscles innervated by medial (not ulnar) **impacted by CTS
 Lateral 2 lumbercals
 Opponents pollicis
 Abductor pollicis brevis
 Flexor pollicis brevis
Sensory Innervation:
Sensory Innervation
Lecture 17: Joints
Types of Joints
 Cartilaginous
o Primary; temporary joints in long bones, “epihyses”
o Secondary: “symphases”- strong, slightly movable joints (IV discs)
 Fibrous
o Sutures of skull
o Syndesmosis: interosseus membranes of forearm/legcompartment syndrome
o Gomphosis: dentoalveolar joint (holds teeth in sockets)
 Synovial Joints
o Articular surfaces lined w/ cartilage
o contained in fibrous joint capsule
o Secrete synovial fluid
o May have articular disc/meniscus
o Joint Types
 Plane- AC joint (gliding)
 Hinge-elbow: flexion/extension, has collateral ligaments
 Saddle: biaxial (ab/ad-duction and flexon/extension, some circumduction)Carpometacarpal joints
 Condyloid: (same as saddle joints, except one axis greater than other)
metacarpophangial (flexon better than extension)
 Ball and socket: hip
 Pivot: atlantoaxial (rotation around central axis)- tough ligaments!!
Joint Ligaments
 Support joint by connecting bones together
 Intrinsic: part of fibrous joint capsule
 Extrinsic ligaments: separate from joint capsule
Vascular Supply
 Joints get supplied via branches from bearby arteries articular branches, form
anastomoses
 Veins w/ arteries, found in synovial sheath
Innervation: all about proprioception
Busae: fluid-filled sacs, surround and cross joints, communicate w/ snovial cavity, allows structures
to slide over each other (bursitis)
The Shoulder
 SC joint
o Limited circumduction
o Very strong joint capsule, bears load from arm to axial skeleton
o Complete Articular disc: shock absorber
o Anterior and posterior sternoclavicular ligament, interclavicular ligament
o Internal thoracic and suprascapular arteries
o Suprascapular nerves, nerve to subclavious
 AC joint
o Rotation of scapula
o Partial articular disc
o Acromioclavicular ligament, Coracoclavicular ligament, Conoid, Trapezoid ligaments
support joint capsule
o Vulnerable when tackled in shoulder (football, hocky)
o Suprascapular and thoracoacromial arteries
o Lateral pectoral, axillary, lateral supraclavicular nerves
 GH joint
o Many planes of motion, true circumduction
o flexiblelarge ROM, but unstable (rotator cuff keeps stable)
o opening in joint capsule for long head of biceps
o glenoid labrum: deepens the GH joint (fibrocartilage attaches to lip of glenoid fossa)
o subacromial bursa
o circumflex humeral and suprascapular arteries
o Innervation: suprascapular, axillary, and lateral pectoral nerves (proprioception)
Elbow Joint
 Hinging motion, rotatior of forarm
 Hyaline cartilage, NO articular disc
 Radial Collateral: attaches to annular ligament
 Annular ligament: wraps head of radius
 Ulnar collateral: anterior, posterior, oblique cord (stronger stability)
 Articulations
o Radiohumeral (head of radius + capitullum) rotation of forearm
o Ulnarhumeral: (trochlear notch + trochlea) hinging motion
 Radioulnar:
o Proximal
 Permits rotation of radius (pronation/supination)
 Synovial capsule, no mensci or disc
o Distal
 Permits rotation of the ulna
 Anterior and posterior ligaments + triangular ligament= articular disc
 Radiocarpal (wrist) Joint
o Strong joint capsule, dorsal and palmar radiocarpal ligaments, radial and ulnar
collateral ligaments
o Synovial capsule, no mensci or disc
 Intercarpal (wrist) joints:
o Between proximal and distal rowssame movements as radiocarpal joint
o Common joint capsule (except carpometacarpal joint at base of theumb)
 Hand Joints
o Carpometacarpal and intermetacarpal joints
 Synovial joints (no mensisci or discs)
 Finger Joints
o Metacarpophalangeal joints: condyloid joints
o Interphangeal joints: hinge joints
o Thumb: has own synovial capsule
o
Only 2 phalanges, so only one IP joint (no DIP or PIP