Human Movement Exam 2

Talocrural Joint

pronation

supination

pronation

Dorsiflexion (maximum 15-25°)

Abduction (small)

Eversion (small)

supination

Plantarflexion (maximum 40-55°)

Adduction (small)

Inversion (small)

Extensor carpi radialis longus OIAN

O: lateral supracondylar ridge

I: base 2nd metacarpal

A: extension and radial deviation of wrist

N: radial n

Extensor carpi radialis brevis OIAN

O: Lateral epicondyle of humerus

I: posterior aspect base of 3rd MCP

A: extends fingers and abducts hand

N: Radial n

Supinator OIAN

Origin:

- Lateral epicondyle of humerus and ulna

Insertion:

- Lateral surface of proximal third of radius

Action:

- Supinates forearm

innervation

-radial nerve

extensor digitorum OIAN 1

O: lateral epicondyle of humerus,

I:distal phalanges of fingers 2-5

action: extends digits 2-5

innervation: radial nerve

extensor digiti minimi OIAN

Origin: Lateral Epicondyle of Humerus

Insertion: Proximal Phalanx of Digit Five

action: extends 5th digit

innervation: radial nerve

extensor carpi ulnaris OIAN

Origin: Lateral epicondyle of humerus

Insertion: Base of 5th metacarpal

action: wrist extension, ulnar deviation

innervation: radial nerve

Abductor pollicis longus OIAN

Origin: Posterior surface of ulna and radius; interosseous membrane

insertion: base of first metacarpal

action: abducts and extends thumb

innervation: radial nerve

Extensor pollicis brevis OIAN

O: posterior surface of radius and interosseous membrane

I: base of proximal phalanx of thumb

action: extends proximal phalanx of thumb

innervation: radial

Extensor pollicis longus OIAN

O: Posterior surface of ulna and interosseous membrane

I: Base of distal phalanx of thumb

action: extends distal phalanx of thumb

innervation: radial

Extensor indicis OIAN

Origin: posterior surface of ulna; interosseous membrane

Insertion: Extensor expansion of index finger

action: extends index finger

innervation: radial nerve

Flexor digitorum superficialis OIAN

O: Medial epicondyle, coroNoid process and radius

I: Middle phalanx of digits 2-5

A: MCP and PIP flexion, assists wrist flexors

N: MEdian (C7-T1)

Flexor carpi radialis OIAN

O: Medial epicondyle of humerus

I: Base of 2nd and 3rd metacarpals

A: Wrist flexion, radial deviation

N: Median nerve (C6-7)`

Flexor carpi ulnaris OIAN

O: Medial epicondyle of humerus

I: Pisiform and base of 5th metacarpal

A: Wrist flexion, ulnar deviation

N: Ulnar nerve (C8, T1)

palmaris longus OIAN

O: Medial epicondyle of humerus

I: Palmar fascia

A: Assists in wrist flexion

N: Median nerve (C6-7)

flexor digitorum profundus OIAN

O: proximal anterior ulna and interosseous membrane

I: DIPs 2-5

A: flexes DIPs and hand

N: MEDIAN AND ULNAR

flexor pollicis longus OIAN

O:anterior surface of radius and interosseous membrane

I: base of distal phalanx of thumb

A: flexion of thumb, flexion of wrist

N: median

pronator quadratus OIAN

O: Distal 1/4 of ulna

I: Distal 1/4 of radius

A: Forearm pronation

N: Median nerve (C8, T1)

4 articulations within the elbow and forearm complex

•Humero-ulnar joint

•Humeroradial joint

•Proximal radio-ulnar joint

•Distal radio-ulnar joint

capitulum (of humerus) articulates with

head of radius

put a cap on the radius

trochlea articulates with

trochlear notch of ulna

medial epicondyle, insertion site of

common flexor-pronator tendon

lateral epicondyle, insertion site of

common extensor- supinator tendon

radial fossa of humerus

small lateral depression; receives the head of the radius when the forearm is flexed

-above the capitulum

coronoid fossa of humerus

anterior depression that receives the coronoid process of the ulna when forearm is flexed.

olecranon fossa (humerus) articulates with

olecranon process of ulna

-posterior side of humerus

Trochlea, articulate with

trochlear notch (of ulna)

has a lateral lip, medial lip, trochlea groove in the middle

sulcus for ulna nerve

Elbow osteology

humerus (coronoid fossa, trochlea, radial fossa, capitulum)

radius (head of radius)

ulna (coronoid process)

Elbow Osteology: Radius and Ulna

Radial notch

Trochlear notch

Ulna tuberosity, insertion site of brachialis

Radial tuberosity, insertion site of biceps brachii

Fovea (of radius) , articulate with capitulum

Ulna tuberosity, insertion site of

brachialis

Radial tuberosity, insertion site of

biceps brachii

Fovea, articulate with

capitulum

Elbow Osteology: Ulna

Olecranon process

Coronoid process

Radial notch

Supinator crest

Olecranon, insertion site of

triceps brachii

Joints of the Elbow and Forearm

•Humero-ulnar joint

•Pretty stable due to the tight fit between the trochlea and trochlear notch

•Humeroradial joint

•Less congruous joint surface, requires many capsuloligamentous connective tissue for stability

•Proximal radio-ulnar joint

•Distal radio-ulnar joint

which joint is more stable? humeroulnar or humeroradial

humeroulnar

•Pretty stable due to the tight fit between the trochlea and trochlear notch

•Humeroradial joint is Less congruous joint surface, requires many capsuloligamentous connective tissue for stability

Humero-Ulnar Joint

•Hinge joint (Modified...)

•Flexion/extension ONLY ??

Almost a hinge joint but it can do radial and ulnar deviation too, pronation, supination

Humeroradial Joint - what type of joint?

•Pivot Joint

•Door knob

•Spinning of one member around a single axis of rotation

•Flexion/extension

•Concave radial head vs convex capitulum

Spinning movement for pronation and supination

Axis of Rotation of the Elbow

Axis of rotation is going through _____ and __________

•Axis of rotation is going through trochlea and capitulum

Medial lip of the trochlea extends more distally

this axis is Not exactly perpendicular to long axis (axis for flexion and extension)

Carrying Angle

The angle between the humerus and ulna when the arm is in anatomical position.

•Normal cubitus valgus (Extended elbow)

Axis of humerus to long axis of forearm: carrying angle

carrying angle: Axis of ________ to long axis of ___________

humerus

forearm

Variation in Carrying Angle

A. normal carrying angle (Female has a larger carrying angle 10-15 degrees and males 5-10 degrees)

B. excessive cubitus valgus 30 degrees

C. cubitus varus -5 degrees

D. gun stock deformity -15 degrees

A common cause of gunstock deformity: severe fracture through the "growth plate" of the distal humerus in children

who has larger carrying angle? men or women?

women!

women typically have 10-15 degrees

men typically have 5-10 degrees

A. normal carrying angle

Variation in Carrying Angle

(Female has a larger carrying angle 10-15 degrees and males 5-10 degrees)

B. excessive cubitus valgus

Variation in Carrying Angle

30 degrees

C. cubitus varus

Variation in Carrying Angle

-5 degrees

D. gun stock deformity

Variation in Carrying Angle

-15 degrees

A common cause of gunstock deformity: severe fracture through the "growth plate" of the distal humerus in children

connective tissues of the elbow

•Thin articular capsule

what 3 joints does it surround?

what is it strengthened by?

•surrounds the humero-ulnar, humeroradial, and proximal radio-ulnar joints

•strengthened by collateral ligaments (lateral collateral ligament and medial collateral ligament)

Capsule surrounds 3 joints- with synovial fluid inside

Medial Collateral Ligament (MCL) of elbow

what other name does it go by?

•Aka. Ulnar collateral ligament (UCL)

Medial Collateral Ligament (MCL)

discuss the different fibers

•Anterior fibers

•Strongest and stiffest of the MCL

•Provide most significant resistance against a valgus producing force

•Resist valgus throughout the full range of flexion and extension

•Posterior fibers

•Resist valgus-producing force in the extremes of elbow flexion

•Transverse fibers

•Attachment sites on the same bone

•Limited function

•Olecranon to ulna (doesn't provide joint resistance)

•Anterior fibers of MCL (elbow)

•____________ and ___________ of the MCL

•Provide most significant resistance against a ________ producing force

Strongest and stiffest

valgus

•Resist valgus throughout the full range of flexion and extension

goes from humerus to ulna

•Posterior fibers of MCL

•Resist ____________-producing force in the extremes of elbow _____________-

valgus

flexion

goes from humerus to ulna

•Transverse fibers

•Attachment sites on the _________ bone from ______ to __________

•Limited function

(does or does not) provide joint resistance?

same

•Olecranon to ulna (doesn't provide joint resistance)

MCL injury

which 2 are most common?

•Falling onto an outstretched and supinated arm

•Medial collateral ligament (most likely the anterior fibers) injury

•Compression of humeroradial joint --> fracturing radial head

•Repetitive stretching of the ligament

•Elite level baseball pitcher

•MCL reconstruction --> Tommy John surgery

MCL injury

•Falling onto an outstretched and supinated arm

•Medial collateral ligament (most likely the ______________ fibers) injury

•Compression of ____________ joint --> fracturing __________ head

anterior

humeroradial

radial

MCL injury

•Repetitive stretching of the ligament

•Elite level baseball pitcher

•MCL reconstruction --> _____________surgery

Tommy John

Lateral Collateral Ligament (LCL) Complex is made of which two ligaments?

•Radial Collateral Ligament

•Merge with annular ligament

•Resist varus-producing force

•Lateral Ulnar Collateral Ligament

•Thicker

•Attaching to supinator crest (on ulna)

•Resist varus-producing force

•Most taut at full flexion (due to relative posterior location)

•Together with anterior fibers of the MCL --> primary frontal plane stability

Lateral Collateral Ligament (LCL) Complex

•Radial Collateral Ligament

•Merge with _________ ligament

•Resist ___________ -producing force

annular

varus

Lateral Collateral Ligament (LCL) Complex

•Lateral Ulnar Collateral Ligament

•(Thicker or thinner )than radial collateral ligament?

•Attaching to __________ crest (on ulna)

•Resist ________-producing force

•Most taut at full ___________ (due to relative posterior location)

•Together with anterior fibers of the MCL --> primary _________ plane stability

thicker

supinator crest

varus

full flexion

frontal plane

which two ligaments provide primary frontal plane stability of the elbow joint

anterior fibers of the MCL

lateral ulnar collateral ligament of lateral collateral ligament complex

in the Lateral Collateral Ligament (LCL) Complex which is thicker? the radial collateral ligament or the lateral ulnar collateral ligament?

lateral ulnar collateral ligament

medial collateral ligament (anterior fibers)

motions that increase tension

valgus

extension (anterior components)

flexion (posterior components

medial collateral ligament (posterior fibers)

motions that increase tension

valgus

flexion

radial collateral ligament

motions that increase tension

varus

lateral (ulnar) collateral ligament

motions that increase tension

varus

external rotation of the elbow complex

flexion

annular ligament

motions that increase tension

distraction of the radius

Valgus

Outward angulation of the distal segment of a bone or joint, as in knock-knees

Varus

Inward angulation of the distal segment of a bone or joint, as in bowlegs

axis of rotation of the forearm

•The axis of rotation of the forearm passes through the head of the _________ and the head of the _________

•The radius and hand rotates and crosses over an essentially fixed ________ during pronation (reverse movement during supination)

head radius and head of ulna

ulna

Proximal Radio-ulnar Joint

which parts are concave or convex?

convex radial head articulates with concave radial notch on ulna

Connective Tissues of Proximal Radio-ulnar Joint

•____________ ligament

Limits distraction of proximal radioulnar joint

Annular

Annular ligament holds radius head- stabilize

annular ligament

•Holds the proximal _______ against the ulna

•Internal surface is lined with _________ to reduce friction during pronation and supination

•External surface receives attachments from ____________, ________________, and _______________

radius

cartilage

elbow capsule, radial collateral ligament, and supinator muscle

Annular ligament is like a belt- holding radius head against ulna

Ring: annular ligament and radial notch does the rest of the ring

distal radioulnar joint

which parts are convex or concave?

convex ulnar head articulates with concave ulnar notch on radius

Connective Tissues of Distal Radio-ulnar Joint

Triangular fibrocartilage complex (TFCC) (in ulnarcarpal space)

•Primary stabilizer of distal radio-ulnar joint

1.Triangular fibrocartilage disc (TFC)

2.Palmar capsular ligament

3.Dorsal capsular ligament

•Primary stabilizer of distal radio-ulnar joint

1, 2, 3

1.Triangular fibrocartilage disc (TFC)

2.Palmar capsular ligament

3.Dorsal capsular ligament

Triangular Fibrocartilage Complex (TFCC)

•Primary ____________ of the distal radio-ulnar joint

•Reinforces the _________ side of the wrist (limits radial deviation)

•Forms part of the __________ of the radiocarpal joint

•Helps transfer part of the compression forces that naturally cross the hand to the forearm

stabilizer

ulnar

concavity

•TFC, the articular disc, follows the moving radius during pronation & supination

disc is distal to ulnar head

Palmar- disc- dorsal

Interosseous Membrane Structure

•Structure

•Central band - twice the thickness of other fibers, large tensile strength

•Oblique cord

•Distal oblique fibers

central band of interosseous membrane

•Central band - ____________ the thickness of other fibers, large tensile strength

twice

Interosseous Membrane Functions

•Functions

•Binds the radius to the ulna

•Serves as a stable attachment site for several extrinsic muscles of the hand

•Provides a mechanism for transmitting force proximally through the upper limb

•Compression force at the wrist

•The compression force transmitted primarily through the ______________ joint to the __________

•Pull the central band ___________

•(interosseous membrane ) Transfers force to ulna

•Humero-ulnar joint

•Shoulder

radiocarpal joint to the radius

taut

•Distracting force at the wrist (carrying a suitcase)

•____________the central band

•_________ the oblique cord, annular ligament

•Contraction of the brachioradialis assist holding the radius firmly against the ____________ of the humerus

Slack

Taut

capitulum

Arthrokinematics of Humero-Ulnar Joint

extension/flexion which tissues are pulled taut and which are slacked

extension

What tissues are pull taut? flexors, anterior capsule

What tissues are slack? extensors, posterior capsule

flexion

What tissues are pull taut? extensors, posterior capsule

What tissues are slack?flexors, anterior capsule

Arthrokinematics of Humero-Radial Joint

flexion which are taut and which are slacked

Flexion

What tissues are pull taut? posterior capsule, lateral (ulnar) collateral ligament

What tissues are slack? anterior capsule

Pronation and Supination

•The ____________ and hand rotates around an essentially fixed __________ during pronation and supination

•Require simultaneous movement at the

• _____________________ joint

• _____________________joint

• _____________________joint

radius

ulna

Proximal radio-ulnar joint

Distal radio-ulnar joint

Humeroradial joint

Arthrokinematics During Supination

Distal radio-ulnar joint

•___________ ulnar notch of the radius (relative mobile)

•______________ head of ulna (relative fix)

•Roll and glide in the __________ direction

•_________________ capsular ligament is pulled taut at end range --> enhance stability

Concave

Convex

same (concave on convex)

Palmar

Arthrokinematics During Supination

•Proximal radio-ulnar joint

•_______________ rotation of proximal radius due to the constraint of the fibro-osseous ring (annular ligament and radial notch on the ulna)

External

Arthrokinematics During Pronation

Distal radio-ulnar joint

•_______________ ulnar notch of the radius (relative mobile)

•_____________ head of ulna (relative fix)

•Roll and glide in_______ direction

•_____________capsular ligament is pulled taut at end range ---> enhance stability

Concave

Convex

same (concave on convex)

Dorsal

Arthrokinematics During Pronation

•Proximal radio-ulnar joint

•____________ rotation of proximal radius due to the constraint of the fibro-osseous ring (annular ligament and radial notch on the ulna)

Internal

Humero-Radial Joint During Pronation

•A spin of the fovea of the radial head against the __________ of the humerus

Contraction of _______________ generate compression force on the humero-radial joint (especially when elbow at extension)

capitulum

pronator teres

Functional Consideration of Pronation and Supination

•Can be compensated through movements of the ________________

shoulder

Dislocation of the Proximal Radio-Ulnar Joint

•The "pulled-elbow" syndrome

•More common in young children due to

•Ligamentous laxity

•A non-ossified radial head

•Relative reduced strength and slowed reflexes

•↑likelihood of others forcefully pulling on their arms

elbow flexors

•Biceps brachii

•Flexion

•Supination

•Brachialis

•Largest PCSA --> generate largest force

•Brachioradialis

•Longest moment arm for elbow flexion

•Pronator teres

elbow flexor with the

Largest PCSA --> generate largest force

•Brachialis

•Longest moment arm for elbow flexion

Brachioradialis

elbow extensors

•Triceps brachii

•Long head

•Lateral head

•Medial head

•Anconeus

•Mostly slow-twitch fiber (durable type I fibers), provide "background" joint stability

Muscle substitution

•For patient with C6 tetraplegia:

•Loss of motor and sensory function below C6 nerve root level (may lose ability to extend the elbow joint)

•Proximal shoulder muscle (i.e. pectoralis major and/or anterior deltoid) may be used to "extend" the elbow by "locking" the joint.

forearm supinators

primary?

secondary?

primary supinators

supinator

biceps brachii

secondary supinators

•Extensor pollicis longus

•Extensor indicis

•Brachioradialis (from a pronated position)

forearm pronators

primary?

secondary?

primary pronators

pronator teres

pronator quadratus

secondary pronators

flexor carpi radialis

palmaris longus

brachioradials (from a supinated position)

brachioradialis

forearm supinator or pronator? or both? or neither?

is a forearm supinator from a pronated positions

is a forearm pronator from a supinated position

Pronator Teres

forearm pronator

•Also an elbow flexor

e.g.unscrew an overtightened screw