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Shoulder, Elbow, and Wrist
For the Lecture Final Exam
The Pectoral Girdle
• Provides attachment for many muscles that move the upper limb
• Girdle is very light and upper limbs are mobile– Only clavicle articulates with the axial skeleton– Socket of the shoulder joint (glenoid cavity) is
shallow• Good for flexibility, bad for stability
ClavicleAcromio-clavicularjoint
Scapula
(a) Articulated pectoral girdle
Articulated Pectoral Girdle
Figure 8.1a
PLAYPLAY Shoulder
PLAYPLAY Shoulder
Clavicles• Extend horizontally across the superior thorax• Sternal end articulates with the manubrium• Acromial end articulates with scapula• Provide attachment for muscles • Hold the scapulae and arms laterally• Transmit compression forces from the upper limbs to the
axial skeleton• SCAPULA
– Lies on the dorsal surface of the rib cage– Located between ribs 2–7
Arm• Region of the upper limb between the shoulder and
elbow• Humerus
– The only bone of the arm– Longest and strongest bone of the upper limb– Articulates with the scapula at the shoulder– Articulates with the radius and ulna at the elbow– Many structures of the humerus provide sites for muscle
attachment– Other structures of the humerus provide articulation sites for
other bones
Forearm• Formed from the radius and ulna• Proximal ends articulate with the humerus• Distal ends articulate with carpals• Radius and ulna articulate with each other
– At the proximal and distal radioulnar joints
• The interosseous membrane– Interconnects radius and ulna
• In anatomical position; the radius is lateral and the ulna is medial
PLAYPLAY Elbow
Proximal Part of the Ulna
Figure 8.4a, b
Radial notch of the ulna
Olecranon process
Trochlear notch
Coronoid process
Proximal radioulnarjoint
Distal radioulnar joint
Ulnar notch of the radiusHead of ulna
Styloid process of ulna
Interosseousmembrane
Ulna
HeadNeckRadialtuberosity
Radius
Styloid processof radius
(a) Anterior view
Olecranonprocess
Styloid processof radius
Radius
Neck of radius
Head of radius
Ulnar notchof the radius
Head of ulna
Styloid processof ulna
Interosseousmembrane
Ulna
(b) Posterior view
• RADIUS• Contributes heavily to the wrist joint
– Distal radius articulates with carpal bones – When radius moves, the hand moves with it
• ULNA• Main bone responsible for forming the elbow joint with
the humerus• Hinge joint allows forearm to bend on arm• Distal end is separated from carpals by fibrocartilage• Plays little to no role in hand movement
Proximal Ends of the Radius and Ulna
Figure 8.3c, d
Coronoid fossa
Radius
Radialtuberosity
Head ofradius
Capitulum
Trochlea
(c) Anterior view at the elbow region
Humerus
Medialepicondyle
Coronoidprocess ofulna
Ulna
Radial notch
Olecranonfossa
Ulna
Olecranonprocess
Medialepicondyle
(d) Posterior view of extended elbow
Humerus
Lateralepicondyle
Head
Radius
Neck
Copyright © 2011 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Location of styloid processes of radius and ulna. Styloid process
of radius
Head ofulna
Styloid processof ulna(a) Normal position
Copyright © 2011 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
• Carpal bones– Forms the true wrist—the proximal region of the
hand– Gliding movements occur between carpals– Are arranged in two irregular rows– Proximal row from lateral to medial
• Scaphoid, lunate, triquetrium, and pisiform
– Distal row from lateral to medial• Trapezium, trapezoid, capitate, and hamate
– A mnemonic to help remember carpals:• Sally left the party to take Carmen home
Bones of the Hand
Figure 8.6a, b
TrapezoidTrapezium
ScaphoidTriquetrumLunate
CapitateHamate
5 4 3 2 1 54321
Phalanges
Metacarpals
CarpalsCarpals
(a) Anterior view of right hand (b) Posterior view of right hand
Radius Ulna
Sesamoidbones Base
Shaft
ProximalMiddleDistal
Head
Ulna
TriquetrumLunate
CapitateHamate
Pisiform
Carpals
Metacarpals
• Metacarpals form the palm• Numbered 1–5, beginning with the pollex (thumb)
• Phalanges form the digits– Numbered 1–5, beginning with the pollex (thumb)– Named also by whether it is proximal,
intermediate (or middle), or distal.– The pollex does not have a middle phalanx.– The second middle phalanx refers to the second
DIGIT.
Plane Joints
Movement in the transverse or frontal plane only. These are not axial since the movement does not occur around an axis.
Examples are the carpal and tarsal bones, between the articular processes of the vertebrae
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Medial/lateralaxis
Flexion and extension
Uniaxial movement
Hinge Joints
Movement around an axis in the sagittal plane only (uniaxial).
Examples are the elbow, knee, and IPJ = interphalangeal (finger and toe) joints.There are two types of IPJ’s: Distal (DIPJ) and Proximal (PIPJ).
Copyright © 2011 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Pivot Joints
Ulna
Radius
Verticalaxis
Rotation
Rotation movement around a vertical axis (uniaxial).
Examples are between the first two vertebrae and proximal radioulnar joint, where the annular ligament on the ulna encircles the head of the radius
Condyloid Joints
Allows for movement in two planes (biaxial) because the bones are shaped like a condyle in a cup.
Examples are the Metacarpal-phalangeal joints (MPJ’s).
These are calledbiaxial condyloid joints
Saddle Joints
Both bones are concave on one side and convex on the other.
Allows for movement in two planes (biaxial).
Example is at the base of the thumb (between the trapezium and metacarpal I)
Saddle joints are biaxial joints; in primate anatomy, allows for the opposable thumb
Ball and Socket Joints
Allows for movement in three planes (multiaxial).
Examples are the shoulder and hip joints.
Bursae and Tendon Sheaths
Figure 9.4a, b
The knee joint has at least 13 bursae
The Shoulder Joint
Diarthrotic (freely moveable) ball and socket joint:
Humeral head in glenoid cavity
Acromioclavicular ligament
Acromion
Tendon of supraspinatus muscle
Coracoacromial ligament
Trapezoid ligament (part of coracoclavicular ligament)
Clavicle
Conoid ligament (part of coracoclavicular ligament)
Superior transverse scapular ligament
Tendon of long head of biceps brachii muscle
Humerus Tendon of subscapularis muscle
Coracoid process
Articular capsule
Scapula (in part)
Shoulder Joint (Glenohumeral Joint)
Ligaments:Glenohumeral ligaments : 3 fibrous bands• From the anterior glenoid labrum to the anatomical neck of humerus• Reinforce the anterior part of the articular capsule (and are inside the capsule, not
visible from outside.)Coracohumeral ligament• From base of coracoid process to anterior aspect of greater tubercle of humerusTransverse humeral ligament• Runs from greater to lesser tubercle of humerus• Creates a channel , bridging over the intertubercular groove• Site for tendon of long head of biceps brachiiCoracoacromial ligament• From inferior aspect of acromion to coracoid process• Forms a protective “arch” preventing superior displacement of the head• Supraspinatus muscle passes under this arch.
Shoulder Ligaments
Shoulder:Glenohumeral Joint
Shoulder Ligaments
• 10 points on lecture final exam:• Label the following drawing with the names of
the ligaments that attach the clavicle to the scapula and to the head of the humerus.
10 pt Essay Question: Label this (½ pt each)
Essay Answer: ½ pt each
Copyright © 2011 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
The sternoclavicular joint.
Anteriorsternoclavicularligament andjoint capsule
Interclavicularligament
Articulardisc
Manubriumof sternum
Costal cartilageof 1st rib
Costoclavicularligament
Clavicle
(a) Sternoclavicular joint, anterior view
Depression
Protraction
Elevation RetractionPosteriorrotation
(b) Sternoclavicular movements
Copyright © 2011 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Fibrous capsule
Hyalinecartilage
Synovial cavityof the glenoidcavity containingsynovial fluid
Glenoid labrum
Humerus
(b) Cadaver photo corresponding to (a)
Copyright © 2011 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Elbow joint
Articularcapsule
Synovialmembrane
Synovial cavity
Articular cartilage
Coronoid process
Tendon ofbrachialis muscle
Ulna
Humerus
Fat pad
Tendon oftricepsmuscle
Bursa
Trochlea
Articular cartilageof the trochlearnotch
(a) Mid-sagittal section through right elbow (lateral view)
Copyright © 2011 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Humerus
Lateralepicondyle
ArticularcapsuleRadialcollateralligament
Olecranonprocess
(b) Lateral view of right elbow joint
Anularligament
Radius
Ulna
Elbow joint
Copyright © 2011 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Anularligament
Humerus
Medialepicondyle
Ulnarcollateralligament
Ulna
Articularcapsule
Radius
Coronoidprocess ofulna
(c) Cadaver photo of medial view of right elbow
Elbow joint
Copyright © 2011 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Articularcapsule
Anularligament
Coronoidprocess
(d) Medial view of right elbow
Radius
Humerus
Medialepicondyle
Ulnarcollateralligament
Ulna
Elbow joint
Copyright © 2011 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Radius Ulna
Lunate
Triquetrum
Pisiform
HamateCapitate
Scaphoid
Trapezoid
Trapezium
Thumb
Radiocarpaljoint
(a) Right wrist, anterior (palmar) view
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Distalradioulnarjoint
Ulnarcollateralligament
ArticulardiscRadial
collateralligament
Radiocarpaljoint
Intercarpaljoint
(b) Wrist joints, coronal section
Copyright © 2011 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Hamate
Carpo-metacarpalligaments
Pisiform
Lunate
Radius Ulna
Ulnarcollateralligament
Radialcollateralligament
Palmarradiocarpalligament
Intercarpalligaments
Trapezium
Capitate
Scaphoid
(c) Ligaments of the wrist, anterior (palmar) view
Copyright © 2011 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Rheumatoid arthritis
Copyright © 2011 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.
Notice that these are all synovial joints.
Abductor pollicis brevis
Flexor pollicis brevis
Extensor pollicis longus
Flexor pollicis longus Adductor pollicis
Lumbricals
Flexor digitorum profundus
Flexor digitorum superficialis
Opponens digiti minimi
Flexor digiti minimi brevis Abductor digiti minimi
Dorsal interosseus Abductor digiti minimi
Brachial Plexus
ROOTS
TRUNKS
DIVISIONS
CORDS NERVES
Brachial Plexus
Brachial Plexus
• Damage to Brachial Plexus– Congenital (brachial plexus damaged during birth)
• Klumpke’s paralysis– Acquired Brachial Plexus injuries
• Crutch paralysis (total upper extremity paralysis)• Claw Hand • Carpal Tunnel Syndrome, Ape hand, Hand of
benediction • Wrist Drop (Waiter’s Hand)
Major Nerves of the Upper
Extremity
Axillary
Musculocutaneus
Axillary Nerve
• Deltoid• Teres minor
Musculocutaneus Nerve
Supplies anterior muscles of the arm
Axillary
Musculocutaneus
Median Nerve
• Supplies no muscles of the arm• Supplies anterior forearm (except flexor carpi
ulnaris)• Damage can cause
– Carpal Tunnel Syndrome– Hand of benediction– Ape Hand
Patient trying to make a fist
Carpel Tunnel Syndrome
Carpel Tunnel Syndrome
Carpel Tunnel Syndrome
• The median nerve travels under the transverse carpal ligament.
• The nerve is pinched in carpal tunnel syndrome.
MEDIAN NERVE• This is the nerve that gets cut when people try to slit
their wrists. • The arteries are so small in the wrist; people rarely
die from this type of suicide attempt. However, they live with a lot of tissue damage. They are not able to move the thumb towards the little finger, so it is hard to pick up small objects. This is called “ape hand”.
Ulnar Nerve
• Supplies flexor carpi ulnaris• “Funny Bone”• Damage can cause claw hand; cannot adduct
or abduct fingers
Radial Nerve
• Supplies muscles on the posterior arm and forearm– Triceps brachii– Extensor carpi radialis– Extensor digitorum communis
• Damage can cause wrist drop
Carpel Tunnel Syndrome
Ape Hand
Axillary nerve
Ulnar nerve Axillary nerve
Median nerve
Musculocutaneous nerve
Radial nerve Brachial plexus
Ulnar nerve
Radial nerve
Median nerve
Arteries of the Upper Extremity
Radial artery Superficial palmar arch
Ulnar artery Anterior interosseous artery Brachial artery
Arteries of the Upper Extremity
• Subclavian (becomes axillary artery in armpit)• Axillary (becomes brachial artery in arm)
– Supplies triceps brachii
• Brachial (divides into radial and ulnar arteries when it reaches the elbow)– Supplies arm muscles except triceps brachii
• Radial• Ulnar
Axillary
Brachial
Radial
Ulnar
Cephalic
Median cubital
Brachial
Radial
Ulnar
Patient Case
• Susan reports shoulder pain located at the proximal lateral humerus. The pain is worse when sleeping on the right shoulder, and also when she elevates her arm.
• This location is consistent with pain originating from the shoulder cuff tendons, the long head of biceps brachii, or subacromial bursa.
• Her pain may be from the rotator cuff, bursitis, or biceps tendonitis.
• Pain from laying on the shoulder is consistent with pain originating from the subacromial space. The humerus compresses the bursa there when laying on the affected side.
Patient Case
• When the arm is elevated and especially when carrying a load in that position, the subacromial bursa is compressed.
• As the supraspinatus muscle contracts in this position, the blood supply to its tendon is impinged. Repeating these motions during the day may cause a supraspinatus tendon tear, since its nutrient vessels are pinched.
Supraspinatus• The supraspinatus muscle participates in humeral elevation
throughout its range of motion, especially the first 5-10 degrees, so it is under tension most of a person’s waking hours and is vulnerable to tensile overload. The trapezius then takes over most of the rest of the range of motion.
• Supraspinatus is the most vulnerable of the cuff muscles.• Rotator cuff tendinitis produces pain between 60-120
degrees of humeral elevation in relation to the trunk. This range is called the painful arc. Beyond 120 degrees, the tendons have cleared the coracoacromial arch.
• If the pain occurs beyond 120 degrees, it is more likely to be from degeneration of the acromial-clavicular joint.
Rotator Cuff Injury Symptoms
• Pain and tenderness in the shoulder, especially when reaching overhead, reaching behind the back, lifting, pulling or sleeping on the affected side.
• Diagnosis– X-rays– MRI– Ultrasound
Causes of Rotator Cuff Injuries • Normal wear and tear. • Poor posture. When you slouch your neck and shoulders forward, the
space where the rotator cuff muscles reside can become smaller. This can allow a muscle or tendon to become pinched under your shoulder bones (including your collarbone), especially during overhead activities, such as throwing.
• Falling. Using your arm to break a fall or falling on your arm• Lifting or pulling. Lifting an object overhead Likewise, pulling something,
such as a high-poundage archery bow, may cause an injury.• Repetitive overhead movement. This occurs often in athletes, especially
baseball pitchers, swimmers and tennis players. It's also common among people in the building trades, such as painters and carpenters.
Trapezius
• Serratus anterior and trapezius both abduct the arm. Trapezius can abduct the arm through its full range of motion, although it is weaker without serratus anterior.
• Overuse and damage to trapezius can result in a shoulder shrug motion when trying to elevate the arm, and fatigue and pain in that muscle.
• This also might be a cause of Susan’s pain.
Upper Trapezius Strain
• An upper-trapezius strain can be triggered quite easily by consistently overusing the muscle group, even at a low intensity. Because repetitive motions do not allow the affected tissue to rest between movements, they can cause stress and irritation.
• The members of today’s work force don’t often get up to sharpen a pencil, fax documents or walk to the post office to deliver a package. The easy and convenient access of working tools promotes inactivity and therefore a rise in repetitive stress injuries associated with desk and computer work. Simple, everyday movements—like habitually holding a telephone between the ear and shoulder—can trigger upper trapezius pain.
Upper Trapezius Strain• It is easy to understand how the upper trapezius could be in a state
of active insufficiency in certain situations; for example, when the shoulder is elevated and the neck is extended, side-bent and rotated, as when you are cradling a phone between your ear and shoulder.
• Shrugging the shoulders and overhead movements also fatigue trapezius.
• Throughout the day, the upper trapezius might be actively insufficient, while, alternatively, the rhomboids might be passively insufficient (when the shoulders are rounded).
• Developing better posture and moving out of these positions intermittently throughout the workday will place the muscles back at their optimal length.
Trapezius Exercises at the OfficeSitting with upright posture, perform 15–20 reps an hour of the following upper trapezius exercises.1. Scapular Pinches. Roll the shoulders back, and pinch the shoulder blades together.2. Shoulder Shrugs. Raise the shoulders up toward the ears, then lower them back down.3. Neck Side-Bending. Tilt one ear toward the shoulder, and hold briefly. 4. Neck Rotation. Look over one shoulder, and pause briefly. 5. Neck Stretch.•In a standing or seated position, place the right hand on top of the head and let the left arm rest at the side.•Gently pull the head toward the right shoulder with the right hand.•Rotate the head down and look at the right hip. (The stretch should be felt on the left side of the neck/shoulder area.)•Repeat on the opposite side.
Elbow Pain• When the elbow joint capsule is inflamed, the
patient holds the elbow flexed at about 80 degrees.
That is the position at which the least amount of tension is present in the joint capsule and surrounding structures.
Elbow Pain
• Most elbow pain results from overuse injuries; many sports, hobbies and jobs require repetitive hand, wrist or arm movements.
• Elbow pain may occasionally be due to arthritis, but in general, your elbow joint is much less prone to wear-and-tear damage than are many other joints.
Common Causes of Elbow Pain• Fractures, ligament sprains and muscle and tendon tears• Dislocation; usually caused by a fall. Children may dislocate the head of the radius from
being pulled by the arm (nursemaid’s elbow).• Tennis elbow (lateral epicondylitis) from forceful extension of wrist; wrist extension is
painful. Diagnose by resisting extension of third finger, creating pain in lateral epicondyle.• Golfer's elbow (medial epicondylitis) from repeatedly flexing wrists or clenching fingers• Cubital tunnel syndrome, ulnar nerve on the inside of the elbow is irritated or injured• Little league elbow syndrome (pitcher's elbow) — an injury mainly affecting children and
rapidly growing adolescents involved in throwing sports such as baseball• Olecranon bursitis — inflammation of a small sac of fluid (olecranon bursa) on the tip of your
elbow• Osteochondritis dissecans - Caused by reduced blood
flow to the end of a bone, occurs most often in young men, particularly after an injury to a joint.
• Radial tunnel syndrome, which occurs when the radial nerve becomes compressed just beyond the elbow (sometimes called resistant tennis elbow)
Nursemaid’s Elbow
Treatment of Elbow and Wrist Pain
• Splinting• Forearm support bands• Taping• Ultrasound• Manipulation• Exercise• Oral anti-inflammatory medicines• Cortisone injections
Extensor Retinaculum
Patient Case
• George has been a computer programmer for 20 years. He has numbness in his right hand on the thumb, index finger, and middle finger.
• Tapping on the carpal tunnel causes parathesias (tingling) in the median nerve distribution (positive Tinel’s sign).
• Placing his wrist in sustained flexion for one minute also causes the parathesias (positive Phalen’s test).
Patient Case• Treatment began with splinting the wrist in
neutral position and patient education for proper ergonomics (use a wrist pad while typing).
Anti-Deformity Positioning• After trauma to the hand, a custom-fabricated splint is
provided for support and protection during healing.• Because the collateral ligaments of the MP joints are slack
with extension, immobilization in MP extension would place the collateral ligaments at risk for adaptive shortening, limiting joint flexion, which impairs grasp.
• A splint should place the MP joints in flexion. The IP joints should be held in extension to reduce the risk of flexion contractures. The thumb should be placed in slight abduction to prevent contracture.
Ulnar Nerve Damage:Cubital Tunnel Syndrome
When the medial epicondyle is struck while the elbow is flexed, the ulnar nerve can be damaged.The extensor digitorum muscle alone can extend the IP joints of the two small fingers if full MPJ extension is prevented. The splint is shaped so the flexor digitorum longus can still flex.
Wartenberg’s Sign
• Ulnar nerve damage can cause claw hand because the flexors become weak, giving the extensors a mechanical advantage, pulling the two little fingers into a claw.
• The little finger may also assume an MPJ abduction position, called Wartenberg’s sign.
Trigger Finger
• Trigger finger is one example of the disability that can be created when repetitive trauma to a flexor tendon results in the formation of nodules on the tendon. Finger flexion may be prevented completely, or the finger may be unable to re-extend.
Pistol Grip
Power Grip
Precision Handling
Cylindrical Grip
Spherical Grip Hook Grip
Lateral prehension
Tapered shape
Carpal Fractures
• Upper extremity fractures are among the most common of the extremity injuries with carpal fractures accounting for 18% of hand fractures and 6 percent of all fractures.
• Of these, fractures to bones of the proximal row are most frequent.
• Fractures of the pisiform bone occur less often than fractures of the scaphoid, lunate, or triquetrum (triangular).
• Pisiform fractures account for 1-3% of all carpal bone osseous injuries
Pisiform Fracture• Most commonly the pisiform is injured in a fall on the outstretched hand with the
wrist in extension or if the heel of the hand is used like a hammer. • When the wrist is in this position, the flexor carpi ulnaris tendon compresses the
pisiform to the triquetrum. • These mechanisms can create an avulsion fracture of the distal aspect of the
pisiform, a linear fracture, or a chondral injury to its dorsal surface. The bone may need to be removed surgically.
Being an anchor for several ligamentous attachments, and the origin of the abductor digiti minimi, there is a 50% chance of an associated injury to the distal radius or to another carpal bone when a fracture of the pisiform is identified.
Scaphoid Fracture• Scaphoid fractures are among the most common injuries. • They frequently occur following a fall onto an outstretched
hand. • X-rays taken soon after the injury may not reveal a fracture,
but the clinician should assume one is present until definitive proof otherwise is obtained.
Of all carpal fractures, scaphoid fractures are by far the most common, accounting for 10% of all hand fractures and 60-70% of all carpal fractures.
Anatomical Snuffbox• The anatomical snuffbox is a triangular
deepening on the radial, dorsal aspect of the hand—at the level of the carpal bones, specifically, the scaphoid and trapezium bones forming the floor.
The name originates from the use of this surface for placing and then sniffing powdered tobacco, or “snuff.”
Anatomical Snuffbox• The radius and scaphoid articulate deep to the snuffbox to form the basis
of the wrist joint. In the event of a fall onto an outstretched hand, this is the area through which the brunt of the force will focus.
• This results in these two bones being the most often fractured of the wrist. In a case where there is localized tenderness within the snuffbox, the fracture is likely to be of the scaphoid.
• The scaphoid is a small, oddly shaped bone whose purpose is to facilitate mobility rather than confer stability to the wrist joint.
• In the event of inordinate application of force over the wrist, this small scaphoid is clearly likely to be the weak link.
• Interestingly, scaphoid fracture is one of the most frequent causes of medico-legal issues.
Anatomical Snuffbox
• An interesting anatomical anomaly in the vascular supply to the scaphoid is the area to which the blood supply is first delivered.
• Blood enters the scaphoid distally. Consequently, in the event of a fracture the proximal segment of the scaphoid will be devoid of a vascular supply, and will—if action is not taken—avascularly necrose within a sufferer's snuffbox.
• Due to the small size of the scaphoid and its shape, it is difficult to determine, early on, whether or not the scaphoid is indeed fractured with an x-ray.