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Dr. Vohra
Elbow Radioulnar & Wrist Joints
Bones involved are
Elbow Joint
Type
Hinge type of synovial joint
Articulation
B/W the trochlea & capitulum of humerus
& trochlear notch of ulna & head of the radius
Fibrous Capsule
The fibrous capsule completely encloses the joint. Its anterior and posterior
parts are thin and weak, but collateral ligaments strengthen its sides.
The fibrous capsule is attached to the proximal margins of the coronoid
and radial fossae anteriorly, but not quite to the superior limit of the
olecranon fossa posteriorly.
Distally the fibrous capsule is attached to the margins of the trochlear
notch, the anterior border of the coronoid process, and the annular
ligament.
Synovial membrane
Lines the internal surface of the fibrous capsule
Ligaments
Lateral ligament
Medial ligament
Lateral ligament (radial collateral)
Is triangular ligament, its apex is attached proximally to the lateral
epicondyle of the humerus and its base blends with the annular ligament of
the radius
Medial ligament (ulnar collateral)
It is composed of anterior and posterior bands (parts), which are connected
by a thinner, relatively weak oblique band.
Its apex is attached to the medial epicondyle of the humerus.
The strong cord-like anterior part is attached to the tubercle on the coronoid
process of the ulna and the weaker fan-like posterior part is attached to the
medial edge of the olecranon.
The ulnar nerve passes posterior to the medial epicondyle and is closely
applied to the ulnar collateral ligament.
Movements & muscles
of the Elbow joint
This joint can be
flexed or extended
Flexion is produced by the
brachialis and brachioradialis
muscles, but the main flexor is
the brachialis. When the
forearm is supinated, the
biceps brachii muscle also
flexes this joint; when it is
pronated, the pronator teres
does.
The main extensor of the elbow
joint is the triceps brachii muscle.
Gravity and the anconeus muscle
assist with this movement.
Blood supply of the Elbow joint
Nerve supply
The joint is supplied by the branches of median,
ulnar, musculocutaneous & radial nerves
Relations of the elbow joint
Anteriorly: Brachialis, tendon of biceps, median
nerve & brachial artery
Posteriorly: Triceps a small bursa
Medially: Ulnar nerve
Laterally: Common extensor tendon & supinator
Carrying angle of the Elbow joint
Radioulnar
Joint
The radius and ulna
articulate with each other
at their proximal and
distal ends at synovial
joints, called the proximal
and distal radioulnar
joints. These articulations
are the pivot type of
synovial joint that
produces pronation and
supination.
Proximal radioulnar joint
Articulation
The radial head articulates with the radial notch of the ulna.
The head of the radius is held in position by the strong annular
(annular) ligament,
Fibrous Capsule
The fibrous capsule enclosing the joint is continuous with the fibrous
capsule of the elbow joint
Synovial membrane
The deep surface of the annular ligament is lined with synovial
membrane. Continues above with elbow joint
Ligaments
The annular ligament is attached to anterior & posterior margins of
radial notch. It is continuous with the capsule of the elbow joint. It is
not attached to radius
Nerve supply
The joint is supplied by the branches of median,
ulnar, musculocutaneous & radial nerves
Movements
pronation and supination of
the forearm
Relations
Anteriorly: Supinator & radial nerve
Posteriorly: Supinator & common extensor tendon
Medially: Ulnar nerve
Laterally: Common extensor tendon & supinator
Distal radioulnar joint
Type
Pivot type of synovial joint
Articulation
Head of the ulna & ulnar notch of radius
Capsule
The capsule encloses the joint but deficient superiorly
Ligaments
Weak anterior & posterior ligaments strengthen the joint
Articular disc
Triangular fibrocartilaginous, separates the cavity of the distal radioulnar
joint from the cavity of the wrist joint. Unites the radius & ulna
Synovial membrane
Lines the capsule
Nerve supply
Anterior interosseous & deep branch of radial nerves
Movement
Supination & pronation
Distal radioulnar joint
Wrist joint (radiocarpal)
Type
It is a condyloid type of synovial joint
Articulation
distal end of the radius and the articular disc above & scaphoid, lunate &
triquetral bones below
Capsule
The capsule encloses the joint & is attached above to the distal ends
of radius & ulna below to the proximal row of carpal bones
Ligaments
Anterior & posterior ligaments strengthen the capsule the medial is
attached to the styloid process of ulna & to the triquetral bone. The
lateral ligament is attached to the styloid process of radius & to the
scaphoid bone
Cont. Wrist
joint (radiocarpal)
Synovial membrane
Lines the capsule & attached to the margins of the articular surfaces.
The joint cavity does not communicate with that of distal radioulnar
joint or with the joint cavities of intercarpal joints
Nerve supply
Anterior interosseous & deep branch of radial nerves
Movement
The movements of adduction, abduction, flexion, extension and
circumduction are possible.
Rotation of the wrist joint is impossible because the articular surfaces are
ellipsoid in shape; however, pronation and supination of the hand
compensate for the absence of this movement
Fractures of the wrist (e.g., Colles' fracture)
involving the distal end of the radius are the
most common type of fracture in persons
over 50 years of age