BIOMECHANICS OF ELBOW
COMPLEX
U.RADHAKRISHNAN.M.P.T
INTRODUCTION
⚫ Elbow complex is designed to
serve hand.
⚫ They provide MOBILITY for
Hand in space by apparent
shortening and Lengthening of
upper extremity.
⚫ They provide Stability for skillful
and forceful movements
ELBOW JOINT
HUMERO ULNAR JOINT
⚫ ARTICULATIONS OF HUMEROULNAR
JOINT
⚫ The articulating surface on the Humerus
is Hour glass shaped TROCHLEA
⚫ The articulating surface on Ulna is a
semicircular shaped concave surface
called TROCHLEAR NOTCH
HUMERO RADIAL JOINT
⚫ ARTICULATION OF HUMERORADIAL
JOINT
⚫ The articulating surface on the Humerus
is spherical – shaped CAPITULUM
⚫ The articulating surface on the RADIUS
is the cup shaped Radial head surrounded
by a rim
ARTICULATIONS OF JOINT
⚫ IN EXTENSION
⚫ The OLECRANON PROCESS enter the
olecranon fossa in Humeroulnar Joint
⚫ There is no contact between the
articulating surfaces in Humeroradial Joint.
ARTICULATIONS OF JOINT
⚫ IN FLEXION
⚫ The Trochlear ridge of Ulna slides along
the Trochlear groove until the Coronoid
process reaches the Coronoid fossa in
Humeroulnar joint
⚫ The radial head slides over capitulum and
reaches Radial fossa in Full Flexion.
JOINT CAPSULE
⚫ The Humeroulnar , Humeroradial and
Superior Radioulnar Joint are enclosed in
a single Joint capsule.The capsule is fairly
loose .
⚫ Anteriorly, it is attached above coronoid
and radial fossa
⚫ Posteriorly ,it is attached above Olecranon
fossa.
LIGAMENTS
⚫MEDIAL COLLATERAL LIGAMENT
Extends from Medial epicondyle of
Humerus to Coronoid and
Olecranon process of Ulna
⚫LATERAL COLATERAL LIGAMENT
Extends from Lateral Epicondyle of
Humerus to Annular Ligament and
Olecranon process.
⚫ ANNULAR LIGAMENT
It encircles the head of Radius
LIGAMENTS OF ELBOW
Movements of Elbow Joint
⚫ FLEXION-EXTENSION ( 0-140 degree)
⚫ AXIS-------Medio Lateral Axis (Passess
through Trochlea)
⚫ PLANE------Saggital plane
⚫ MUSCLES:
⚫ FLEXORS OF ELBOW
⚫ Biceps Brachi---Powerful flexor when
elbow is in 90 degree Flexion.
⚫ Brachialis----Flexor of elbow in all position
⚫ Brachioradialis---Flexor of elbow in
midprone position
BICEPS BRACHI
EXTENSORS OF ELBOW
⚫ TRICEPS is the powerful extensor of the
Shoulder
⚫ Long head of Triceps depends on
Shoulder Position
⚫ Medial head of Triceps is active in
unresisted Elbow
extension
⚫ All three Heads of Triceps are active when
heavy resistance is given to Extension.
CARRYING ANGLE
⚫ The angle formed between the axis of
Humerus and the Longitudinal axis of
Forearm
⚫ Normal angle: In MEN=5 degree ,
In WOMEN=10 degree
⚫ The angle is more in Women due to
Wider Pelvis
⚫ CUBITUS VALGUS: Increase in Carrying
Angle
⚫ CUBITUS VARUS: Decrease in Carrying
CARRYING ANGLE
SUPERIOR RADIOULNAR
JOINT
⚫ ARTICULATION
⚫ The Radial notch on Ulna articulate with
Head of Radius along with Annular
Ligament & Capitulum.
⚫ LIGAMENTS
⚫ Annular Ligament-----circle the head of
Radius and keeps the Ulna together.
⚫ Quadrate Ligament----extends from the
Inferior edge of radial notch to Neck of
Radius
⚫ Oblique cord------attached to inferior
part of Radial notch on Ulna to just below
INFERIOR RADIOULNAR
JOINT
⚫ ARTICULATION
⚫ The Ulnar notch of Radius articulates with
head of Ulna along with Articular Disc.
⚫ LIGAMENTS
⚫ Anterior Radio Ulnar Ligament----
attached to anterior aspect just above the
Ulnar head to above Ulnar notch.
⚫ Posterior Radio Ulnar Ligament---
attached to posterior part of Ulnar head
to above Ulnar notch.
⚫ Interosseous Membrane---binds the sha
of Radius and Ulna together.
MUSCLES
⚫ PRONATOR TERES----- helps in
Pronation,it acts in all position of Elbow,
helps in Stabilization of Superio Radio
Ulnar Joint. Active during rapid and
resisted Pronation.
⚫ PRONATOR QUADRATUS---- helps in
Pronation in all position of Elbow
⚫ SUPINATOR---------helps in Supination
in all position of Elbow
⚫ BICEPS BRACHI-------- helps in
Supination when Elbow is flexed to 90
degree
MOVEMENTS
⚫ Pronation & Supination
⚫ Axis of movement extends from radial
head to Ulnar head
⚫ Pronation and Supination movement is
good when Elbow is Flexed to 90 degree
⚫ In Elbow extended position Pronation is
limited due to passive tension in Biceps
Brachi. Supination is limited due to
passive tension in Interosseous Membrane.
PROBLEMS OF ELBOW
⚫ TENNIS ELBOW or LATERAL
EPICONDYLITIS:
⚫ Inflammation at origin of Extensors of
Wrist at Lateral Epicondyle.
⚫ It is caused due to repeated forceful
contraction of Wrist Extensors.
⚫ Extensor carpi radialis brevis is affected
⚫ GOLFER’S ELBOW or MEDIAL
EPICONDYLITIS:
⚫ Inflammation at origin of Flexors of Wrist
at Medial Epicondyle.
⚫ Repetitive contractions of Pronator Teres,
Flexor Carpi Ulnaris
PROBLEMS OF ELBOW
⚫ NURSEMAID’S ELBOW or PULLED
ELBOW
⚫ In small children the radial head is not
fully developed ,li ing small child up in to
by one hand may cause the RADIAL
HEAD to slip out of Annular Ligament.
⚫ CUBITAL TUNNEL SYNDROME
⚫ Repetitive forceful contractions of Flexor
carpi Ulnaris may compress Ulnar Nerve
as it passess through the cubital tunnel
between Medial Epicondyle of Humerus
