Transcript Anatomy Terminology and Tissues

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
Articulated Pectoral Girdle
Acromioclavicular
joint
PLAY
Clavicle
Scapula
Shoulder
(a) Articulated pectoral girdle
Figure 8.1a
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
PLAY
Shoulder
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
PLAY
Elbow
Proximal Part of the Ulna
Radial notch
of the ulna
Head
Neck
Radial
tuberosity
Olecranon process
Head of radius
Trochlear notch
Neck of radius
Coronoid process
Proximal radioulnar
joint
Interosseous
membrane
Ulna
Radius
Styloid process
of radius
(a) Anterior view
Olecranon
process
Ulnar notch of
the radius
Head of ulna
Distal radioulnar joint
Styloid process of ulna
Interosseous
membrane
Ulna
Ulnar notch
of the radius
Radius
Head of ulna
Styloid process
of ulna
(b) Posterior view
Styloid process
of radius
Figure 8.4a, b
• 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
Humerus
Coronoid
fossa
Capitulum
Medial
epicondyle
Head of
radius
Radial
tuberosity
Radius
(c) Anterior view at the elbow region
Trochlea
Coronoid
process of
ulna
Radial notch
Ulna
Humerus
Olecranon
fossa
Olecranon
process
Medial
epicondyle
Lateral
epicondyle
Head
Neck
Ulna
Radius
(d) Posterior view of extended elbow
Figure 8.3c, d
Location of styloid processes of
radius and ulna.
Styloid process
of radius
Head of
ulna
(a) Normal position
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Styloid process
of ulna
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• 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
Phalanges
Distal
Middle
Proximal
Carpals
Hamate
Capitate
Pisiform
Triquetrum
Lunate
Ulna
5
4 3 2
Metacarpals
Head
Shaft
Base
Sesamoid
bones
1
Carpals
Trapezium
Trapezoid
Scaphoid
Radius
(a) Anterior view of right hand
1
2
3
4 5
Carpals
Hamate
Capitate
Triquetrum
Lunate
Ulna
(b) Posterior view of right hand
Figure 8.6a, b
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
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).
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Medial/
lateral
axis
Flexion and extension
Uniaxial movement
Pivot Joints
Vertical
axis
Ulna
Radius
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
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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 called
biaxial 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
The knee joint has at least 13 bursae
Figure 9.4a, b
The Shoulder Joint
Diarthrotic (freely moveable) ball and
socket joint:
Humeral head in glenoid cavity
Trapezoid ligament (part of
coracoclavicular ligament)
Acromioclavicular ligament
Conoid ligament (part
of coracoclavicular
ligament)
Acromion
Tendon of
supraspinatus muscle
Superior transverse
scapular ligament
Coracoacromial ligament
Coracoid process
Tendon of long head of
biceps brachii muscle
Humerus
Clavicle
Articular capsule
Tendon of
subscapularis
muscle
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 humerus
Transverse 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 brachii
Coracoacromial 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
The sternoclavicular joint.
Anterior
sternoclavicular
ligament and
joint capsule
Clavicle
Interclavicular
ligament
Articular
disc
Elevation
Retraction
Posterior
rotation
Protraction
Depression
Costoclavicular
ligament
Costal cartilage
of 1st rib
Manubrium
of sternum
(a) Sternoclavicular joint, anterior view
(b) Sternoclavicular movements
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Glenoid labrum
Synovial cavity
of the glenoid
cavity containing
synovial fluid
Hyaline
cartilage
Fibrous capsule
Humerus
(b) Cadaver photo corresponding to (a)
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Elbow
joint
Articular
capsule
Synovial
membrane
Humerus
Synovial cavity
Articular cartilage
Fat pad
Tendon of
triceps
muscle
Bursa
Coronoid process
Tendon of
brachialis muscle
Ulna
Trochlea
Articular cartilage
of the trochlear
notch
(a) Mid-sagittal section through right elbow (lateral view)
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Elbow
joint
Humerus
Anular
ligament
Radius
Lateral
epicondyle
Articular
capsule
Radial
collateral
ligament
Olecranon
process
(b) Lateral view of right elbow joint
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Ulna
Elbow
joint
Humerus
Anular
ligament
Medial
epicondyle
Radius
Articular
capsule
Coronoid
process of
ulna
(c) Cadaver photo of medial view of right elbow
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Ulnar
collateral
ligament
Ulna
Elbow joint
Articular
capsule
Anular
ligament
Coronoid
process
Radius
Humerus
Medial
epicondyle
Ulnar
collateral
ligament
Ulna
(d) Medial view of right elbow
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Radius
Radiocarpal
joint
Scaphoid
Ulna
Lunate
Triquetrum
Pisiform
Capitate
Trapezoid
Trapezium
Thumb
(a) Right wrist, anterior (palmar) view
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Hamate
Radiocarpal
joint
Radial
collateral
ligament
Intercarpal
joint
(b) Wrist joints, coronal section
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Distal
radioulnar
joint
Articular
disc
Ulnar
collateral
ligament
Palmar
radiocarpal
ligament
Radius
Radial
collateral
ligament
Scaphoid
Intercarpal
ligaments
Ulna
Lunate
Ulnar
collateral
ligament
Pisiform
Hamate
Trapezium
Capitate
Carpometacarpal
ligaments
(c) Ligaments of the wrist, anterior (palmar) view
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Rheumatoid arthritis
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Notice that these are
all synovial joints.
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Extensor pollicis longus
Flexor pollicis brevis
Abductor pollicis brevis
Flexor pollicis longus
Adductor pollicis
Lumbricals
Flexor digitorum
profundus
Flexor digitorum
superficialis
Opponens digiti minimi
Abductor digiti minimi
Flexor digiti minimi brevis
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)
Axillary
Musculocutaneus
Major Nerves
of the Upper
Extremity
Axillary Nerve
• Deltoid
• Teres minor
Axillary
Musculocutaneus
Musculocutaneus Nerve
Supplies anterior
muscles of the arm
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
Brachial plexus
Radial nerve
Musculocutaneous nerve
Median nerve
Axillary nerve
Axillary nerve
Ulnar nerve
Median nerve
Radial nerve
Ulnar nerve
Arteries of the
Upper Extremity
Radial artery
Superficial palmar arch
Ulnar artery
Brachial artery
Anterior interosseous 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
Cephalic
Brachial
Axillary
Brachial
Median
cubital
Radial
Radial
Ulnar
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, sidebent 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 Office
Sitting 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
Tapered shape
Cylindrical Grip
Power Grip
Spherical Grip
Lateral prehension
Hook Grip
Precision Handling
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.