2. THE CUBITAL FOSSA
The cubital fossa is an area of transition between the
anatomical arm and the forearm.
It is located as a depression on the anterior surface of
the elbow joint.
The borders and
contents of the cubital fossa,
clinical relevance.
3.
4. BORDERS
The cubital fossa is triangular in shape, and thus has
three borders:
Lateral border – medial border of the brachioradialis
muscle.
Medial border – lateral border of the pronator teres
muscle.
Superior border – hypothetical line between the
epicondyles of the humerus.
5. The floor of the cubital fossa is formed proximally by
the brachialis, and distally by the supinator muscle.
The roof consists of skin and fascia,
Reinforced by the bicipital aponeurosis.
Within the roof runs the median cubital vein,
which can be accessed for venepuncture
6. CONTENTS
The contents of the cubital fossa include- vessels,
Nerves
The biceps tendon (lateral to medial):
Radial nerve – this is not always strictly considered part
of the cubital fossa, but is in the vicinity, passing
underneath the brachioradialis muscle.
Here the radial nerve divides into its deep and
superficial branches.
7. Biceps tendon – runs through the cubital fossa,
attaching to the radial tuberosity, just distal to the neck
of the radius.
Brachial artery – supplies oxygenated blood to the
forearm.
It bifurcates into the radial and ulnar arteries at the
apex of the cubital fossa.
Median nerve – leaves the cubital between the two
heads of the pronator teres.
It supplies the majority of the flexor muscles in the
forearm.
8.
9. Clinical Relevance
Brachial Pulse and Blood Pressure
The brachial pulse can be felt by palpating immediately
medial to the biceps tendon in the cubital fossa. When
measuring blood pressure, this is also the location in
which the stethoscope must be placed, to hear the
korotkoff sounds.
Venepuncture
The median cubital vein is located superficially within the
roof of the cubital fossa. It connects the basilic and
cephalic veins, and can be accessed easily – this makes it
a common site for venepuncture.
10. Supracondylar Fractures
A supracondylar fracture is a common fracture in the
young, and usually occurs by falling onto a hyper-
extended elbow.
• It is a transverse fracture, spanning between the two
epicondyles.
•It can also occur by falling onto a flexed elbow, but this
accounts for <5% of cases.
•The displaced fracture fragments may impinge and
damage the contents of the cubital fossa.
11.
12. Direct damage, or post-fracture swelling can
cause interference to the blood supply of the
forearm from the brachial artery.
The resulting ischaemia can cause Volkmann’s
Ischaemic contracture –
This is uncontrolled flexion of the hand, as
flexors muscles become fibrotic and short.
There also can be damage to the median or
radial nerves.
13. The elbow joint
The elbow is the joint connecting the upper arm to
the forearm.
TYPE: It is classed as a hinge-type synovial joint.
The anatomy of the elbow joint;
Its articulating surfaces,
Movements,
Stability
The clinical relevance.
14. Articulating Surfaces
It consists of two separate articulations:
Trochlear notch of the ulna and the trochlea of the
humerus
Head of the radius and the capitulum of the
humerus
The proximal radioulnar joint is found within same
joint capsule of the elbow,
• May be considered as a separate articulation.
15.
16.
17. Joint Capsule and Bursae
Like all synovial joints, the elbow joint has a capsule
enclosing the joint.
This is strong and fibrous, strengthening the joint.
The joint capsule is thickened medially and laterally
to form collateral ligaments,
which stabilise the flexing
Extending motion of the arm.
18. A bursa is a membranous sac filled with synovial
fluid.
It acts as a cushion to reduce friction between the
moving parts of a joint, limiting degenerative damage.
There are many bursae in the elbow, but only a few
have clinical importance:
1. Intratendinous – located within the tendon of the
triceps brachii.
19. 2. Subtendinous – between the olecranon and the
tendon of the triceps brachii, reducing friction between
the two structures during extension and flexion of the
arm.
3. Subcutaneous (olecranon) bursa – between the
olecranon and the overlying connective tissue
(implicated in olecranon bursitis).
20. Ligaments
The joint capsule of the elbow is strengthened
by ligaments medially and laterally.
The radial collateral ligament is found on the
lateral side of the joint,
Extending from the lateral epicondyle,
Blending with the annular ligament of the
radius (a ligament from the proximal radioulnar
joint).
21. The ulnar collateral ligament originates from the
medial epicondyle,
Attaches to the coronoid process
olecranon of the ulna.
22.
23. Neurovasculature
The arterial supply to the elbow joint is from
the cubital anastomosis,
Includes recurrent and collateral branches from
the brachial and deep brachial arteries.
Its nerve supply is provided by the median,
musculocutaneous and radial nerves anteriorly,
The ulnar nerve posteriorly.
24. Movements of the Joint
The orientation of the bones forming the elbow joint
produces a hinge type synovial joint,
Allows for extension and flexion of the forearm:
Extension – triceps brachii and anconeus
Flexion – brachialis, biceps brachii, brachioradialis
Note – pronation and supination do not occur at the
elbow – they are produced at the nearby SUPERIOR
radioulnar joints.
25. Muscles that cross the elbow joint
Anteriorly,
The humeral head of the pronator teres is attached to
the medial epicondyle of the humerus along with the
flexor carpi radialis,
The palmaris longus (if present),
The humeroulnar head of the flexor digitorum
superficialis,
The humeral head of the flexor carpi ulnaris at the
common flexor origin.
26. The ulnar head of the pronator teres attaches at the
coronoid process,
The ulnar head of the flexor carpi ulnaris attaches at
the olecranon.
The humeroulnar head of the flexor digitorum
superficialis does extend over to the coronoid process.
Posteriorly,
The extensor carpi radialis longus has its proximal
attachment at the lateral supraepicondylar ridge.
27. The extensor carpi radialis brevis,
Extensor digitorum, and
Extensor digiti minimi all have their proximal attachment
The lateral epicondyle of the humerus at the common
extensor origin and cross the joint.
28. Clinical Relevance
Injuries to the Elbow Joint
1. Bursitis
Subcutaneous bursitis: Repeated friction and
pressure on the bursa can cause it to become
inflamed.
Because this bursa lies relatively superficially, it
can also become infected
Such as cut from a fall on the elbow
.
29. Subtendinous bursitis:
This is caused by repeated flexion and extension
of the forearm,
commonly seen in assembly line workers.
Usually flexion is more painful as more pressure
is put on the bursa
DISLOCATIONS
An elbow dislocation usually occurs when a young child
falls on a hand with the elbow flexed.
30. The distal end of the humerus is driven through the
weakest part of the joint capsule, which is the
anterior side.
The ulnar collateral ligament is usually torn and
there can also be ulnar nerve involvement
Most elbow dislocations are posterior,
It is important to note that elbow dislocations are
named by the position of the ulna and radius, not the
humerus.
31.
32. Epicondylitis (Tennis elbow or Golfer’s elbow)
Most of the flexor and extensor muscles in the forearm
have a common tendinous origin.
The flexor muscles originate from the medial
epicondyle, and the extensor muscles from the lateral.
Sportspersons can develop an overuse strain of the
common tendon –
which results in pain and inflammation around the
area of the affected epicondyle.
33. Typically, tennis players experience pain in the
lateral epicondyle from the common extensor origin.
Golfers experience pain in the medial epicondyle
from the common flexor origin.
This is easily remembered as golfers aim for the
‘middle’ of the fairway,
while tennis players aim for the ‘lateral’ line of the
court!
34.
35. Supracondylar Fracture
A supracondylar fracture usually occurs due to a fall
onto on outstretched, extended hand in a child (95%) but
more rarely can occur by a direct impact onto a flexed
elbow.
It is typically a transverse fracture, spanning between
the two epicondyles in the relatively weak epicondylar
region
formed by the olecranon fossa and coronoid fossa
which lie opposite each other in the distal humerus.
36. Direct damage, or swelling can cause the interference
to the blood supply of the forearm via the brachial artery.
The resulting ischaemia can cause Volkmann’s
ischaemic contracture – uncontrolled flexion of the hand,
as flexors muscles become fibrotic and short.
There also can be damage to the medial, ulnar or
radial nerves.
The neurovascular examination and documentation of
all patients presenting with these injuries is vital.
The blood supply can be interrupted acutely leading to
a ‘pale, pulseless’ limb often in a child, usually requiring
emergency surgery
