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Chapter 15
The Elbow Complex
Overview


The elbow complex is an inherently strong
and stable compound joint, which is
enclosed within the capsule of the cubital
articulation. The stability of the elbow
complex, gives it very little in the way of
compensatory adjustments, making it prone
to overuse injuries
The primary function of the elbow complex
is to work together with the shoulder to
position the hand for functional activities
Anatomy

The elbow complex is comprised of
three distinct articulations:
– The humeroulnar joint
– The humeroradial joint
– The proximal radioulnar joint
Humeroulnar Joint
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A uniaxial hinge joint formed between
the trochlear notch of the proximal
ulna and the spool-shaped trochlea of
the humerus
The angulation of this joint forms the
“carrying angle”
The carrying angle is approximately
11-14° in males and 13-16° in females
Humeroradial Joint
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A uniaxial hinge joint formed between
the spherical capitellum of the
humerus, and the concave head of the
radius
The design of this joint allows the
elbow to flex and extend, and for the
radius to rotate
Proximal Radioulnar Joint
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The proximal (superior) radioulnar joint is a
uniaxial pivot joint formed between the
periphery of the convex radial head, and the
fibrous osseous ring formed by the concave
radial notch of the ulna
The annular ligament forms 80% of the
articular surface of the proximal radioulnar
joint
Joint Capsule


The joint capsule of the elbow
complex is thin but strong
The capsule of the joint does not
respond well to injury or prolonged
immobilization, and often forms thick
scar tissue, which may result in flexion
contractures of the elbow
Medial (Ulnar) Collateral
Ligament
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
The fan-shaped MCL is functionally the most
important ligament in the elbow for
providing stability against valgus stress,
particularly in the range of 20-130° of
flexion and extension
There are three distinct components of the
MCL:
– Anterior bundle
– Transverse bundle
– Posterior bundle
Medial (Ulnar) Collateral
Ligament

Anterior bundle
– Anterior band
The strongest and stiffest of the elbow
collateral ligaments
 Primarily stabilizes the elbow against valgus
stress in the ranges of 20-120° of flexion, and
becomes a secondary restraint with further
flexion

Medial (Ulnar) Collateral
Ligament

Anterior bundle
– The posterior band
Taut beyond 55° of elbow flexion
 A secondary restraint to valgus stress at
lesser degrees of flexion
 An equal co-restraint with the anterior band
at terminal elbow flexion
 A primary restraint to passive elbow extension

Medial (Ulnar) Collateral
Ligament

The transverse bundle
– Also known as Cooper’s ligament
– Fibers both originate and insert on the
ulna and therefore have little role in
elbow stability
Medial (Ulnar) Collateral
Ligament

Posterior bundle
– Appears to be a thickening of the
posterior elbow capsule
– Provides only secondary restraint to
valgus stress at flexion beyond 90°.
Lateral (Radial) Collateral
Ligament

Consists of:
–
–
–
–

The
The
The
The
annular ligament
fan-like radial collateral ligament
accessory collateral ligament
lateral ulnar collateral ligament
The LCL functions to maintain the
ulnohumeral and radiohumeral joints in a
reduced position when the elbow is loaded
in supination
Annular Ligament

The annular ligament functions to
maintain the relationship between the
head of the radius and the humerus
and ulna
Bursae
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
The olecranon bursa is the main bursa of
the elbow complex and lies posteriorly
between the skin and the olecranon process
Under normal conditions the bursa does not
communicate with the elbow joint, although
its superficial location puts it at high risk for
injury from direct trauma to the elbow
Elbow Flexors


The prime movers of elbow flexion are
the biceps, brachialis, and
brachioradialis
The pronator teres, flexor carpi radialis
(FCR), and flexor carpi ulnaris (FCU),
and the extensor carpi radialis longus
(ECRL) muscles are considered as
weak flexors of the elbow
Elbow Extensors

There are two muscles that extend the
elbow: the triceps and the anconeus
Forearm Pronators
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Pronator teres
Pronator quadratus
Flexor carpi radialis
Forearm Supinators
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
Biceps
Supinator
Cubital tunnel

A fibro-osseous canal that contains the ulnar
nerve
– The floor of the tunnel is formed by the MCL
– The roof is formed by an aponeurosis, the
arcuate ligament
– The medial head of the triceps constitutes the
posterior border of the tunnel
– The anterior and lateral borders are formed by
the medial epicondyle and olecranon,
respectively

The volume of the cubital tunnel is greatest
with the elbow held in extension
Cubital Fossa

The cubital fossa represents the
triangular space, or depression, which
is located over the anterior surface of
the elbow joint, and which serves as
an ‘entrance’ to the forearm, or
antebrachium
Cubital Fossa

The contents of the fossa include:
– The tendon of the biceps brachii lies as
the central structure in the fossa
– The median nerve
– The brachial artery
– The radial nerve
– The median cubital or intermediate
cubital cutaneous vein
Nerves
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Ulnar
Radial
Median
The Arcade of Fröhse


The arcade of Fröhse is an inverted
arched structure that lies within 1 cm
distal of the fibrous edge of the ECRB
and approximately 2 to 4 cm distal to
the radiohumeral joint
It represents the proximal border of
the superficial head of the supinator,
through which the radial nerve passes
The Radial
Tunnel/Supinator Canal

The radial tunnel lies on the anterior
aspect of the radius, and is
approximately three to four finger
breadths long, beginning just proximal
to the radiohumeral joint, and ending
at the site where the nerve passes
deep to the superficial part of the
supinator muscle
Biomechanics

Biomechanically, the elbow
predominantly functions as an
important link in the upper extremity
kinetic chain, allowing the generation
and transfer of forces which occur in
the upper extremity.
Humeroulnar Joint
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

The resting, or open pack, position for
the humeroulnar joint is 70° of flexion
with 10° of forearm supination
The closed pack position is full
extension and maximum forearm
supination
The capsular pattern is much more
limitation in flexion than extension
Humeroradial Joint



The resting, or open pack, position of the
humeroradial joint is extension and forearm
supination
The closed pack position is approximately
90° of elbow flexion and 5° of supination
There is no true capsular pattern at this
joint, although clinically an equal limitation
of pronation and supination is observed
Proximal Radioulnar Joint
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
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The resting, or open pack, position for
the proximal radioulnar joint is 70°
flexion and 35° of forearm supination
The closed pack position is 5° of
forearm supination
The capsular pattern is minimal to loss
of motion, with pain at the end ranges
of pronation and supination
Force Couples of the
Elbow
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
The triceps/biceps during arm extension and
flexion
Flexor carpi radialis (FCR), flexor carpi
ulnaris (FCU), flexor digitorum communis
(FDC)/Extensor carpi radialis longus (ECRL),
extensor carpi radialis brevis (ECRB),
extensor communis (EC) during wrist flexion
and extension
Force Couples of the
Elbow
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
Pronator teres, pronator
quadratus/supinator during forearm
pronation and supination
Triceps/biceps, brachioradialis;
pronator teres/supinator; FCR,
FCU/ECRB, ECRL during activities
requiring elbow stabilization
Examination

History
– During the history, the clinician must
determine the chief complaint and
whether there is a specific mechanism of
injury
Where is the pain?
 Was there any antecedent trauma or
overuse?
 Is there any paresthesia?
 What makes the symptoms better/worse

Examination

Systems Review
– The clinician should be able to determine the
suitability of the patient for physical therapy
– If the clinician is concerned with any signs or
symptoms of a visceral, vascular, neurogenic,
psychogenic, spondylogenic or systemic disorder
that is out of the scope of physical therapy, the
patient should be referred to an appropriate
healthcare provider
Examination

Observation
– The affected elbow should be inspected
for scars, deformities, and swelling
– The clinician should observe the ‘carrying
angle’ of the elbow and compare it to the
other side
Examination
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Palpation
– Because they are superficial, most of the
elbow structures are easily palpable,
making it easier for the clinician to
pinpoint the specific area of pain
Examination

Active range of motion with passive
overpressure
– It is important to determine how much range of
motion (ROM) is necessary for the patient to
perform his or her job and recreational activities
– The patient is asked to perform active flexion,
extension of the elbow, pronation and supination
of the forearm, and wrist flexion and extension.
The ranges are recorded
Examination
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Resistive testing
– In addition to all of the shoulder muscles
that insert at or near the elbow (biceps,
brachialis, triceps), the clinician must also
test the muscles responsible for elbow
flexion, and extension, forearm
supination, pronation, and wrist flexion
and extension
Examination

Functional assessment
– A number of tests have been designed to
assess elbow function
Examination

Passive articular motion testing
– The
– The
– The
– The
ulnohumeral joint
radiohumeral joint
proximal radioulnar joint
distal radioulnar joint
Examination

Stress tests
– Medial (ulnar) collateral ligament (valgus
test)
– Lateral (radial) collateral ligament (varus
test)
Examination

Special tests
– Tennis elbow tests
Cozen’s test
 Mill’s test

– Golfer’s Elbow test
– Cubital tunnel syndrome tests
Elbow flexion
 Pressure provocative test

– Tinel’s Sign (at the elbow)
Intervention Strategies

Acute Phase
– Protection of the injury site
– Restoration of pain-free range of motion in the
entire kinetic chain
– Improve patient comfort by decreasing pain and
inflammation
– Retard muscle atrophy
– Minimize detrimental effects of immobilization and
activity restriction
– Maintain general fitness
– Patient to be independent with home exercise
program
Intervention Strategies

Functional Phase
– Attain full range of pain free motion
– Restore normal joint kinematics
– Improve muscle strength to within normal
limits
– Improve neuromuscular control
– Restore normal muscle force couples