Hand

19 Bones

19 Articulations

29 Muscles

Bones of the Hands

Arches of the Hand

• Transverse carpal arch

• Transverse metacarpal arch

• Longitudinal arch

Mobility of 4th and 5th CMC Joints

Creases of the Hand • Distal digital crease

• Middle digital crease• Proximal digital

crease• Distal palmar crease• Proximal palmar

crease• Thenar crease• Distal wrist crease• Proximal wrist crease

Volar or Palmar Plates

• Volar or Palmar Plates are dense thick discs of fibrocartilage which help to strengthen joint and prevent hyperextension

• Note the fibrous digital sheath in top picture (annual pulley)

Motions at the MP Joints

• Flexion and Extension– Axis - Lateral– Plane - Sagittal

• Abduction and Adduction– Axis - Anterior/Posterior – Plane – Frontal

Motions at the PIP and DIP Joints

• Flexion and Extension– Axis - Lateral– Plane - Sagittal

Extrinsics• Muscles originating

outside the hand– Flexor Digitorium

Superficialis – Flexor Digitiorium

Profundus – Flexor Pollicus Longus – Extensor Digitorum– Extensor Indicis Proprius– Extensor Digiti Minimi– Extensor Pollicus Longus– Extensor Pollicus Brevis– Abductor Pollicus Longus

Intrinsics• Four Lumbricals• Three Palmar

Interossei• Four Dorsal Interossei• Thenar muscles

– Opponens Pollicus– Abductor Pollicus

Brevis– Adductor Pollicus– Flexor Pollicus Brevis

Intrinsics

• Hypothenar muscles– Opponens Digiti Minimi– Abductor Digiti Minimi– Flexor Digiti Minimi Brevis

• Palmaris Brevis

Flexor Tendons

Flexor Digitorum SuperficialisTest for Tendon Integrity

• Therapist holds all fingers except one being tested in extension. This isolates the Flexor Digitorum Superficialis. If client can flex at PIP joint then FDS tendon is intact.

Flexor Digitorum ProfundusTest for Tendon Integrity

• Therapist extends all joints of client’s finger except the DIP. Therapist asks client to flex the DIP. If client can, FDP is intact

Annular Pulleys

• Hold flexor tendons relatively close to joint (functional insertions)

• Rupture results in bowstringing with less ROM and strength

• Trigger finger

Extensor Assembly

• Over the proximal phalanx the extensor tendon (from extensor digitorum) divides into a central band and two lateral bands

• The central band inserts at the base of the middle phalanx

• The two lateral bands rejoin over the middle phalanx and insert at the base of the distal phalanx

Extensor Mechanism

Extensor Mechanism

Extensor MechanismClosed pack position

• MCP 70 degrees

• PIP/DIP extension

Closing Hand

Opening Hand

Relationship of AB & Adduction to Flexion and Extension at MP Joints

• When MP joints are extended – the collateral ligaments are slack and allow for AB and Adduction of Fingers

• When MP joints are flexed – the collateral ligaments are taut (tight) and prevent AB and ADduction

Position for Long Term Immobilization

• Metacarpalphalangeal joints in 60 to 70 degrees of flexion

• PIP and DIP joints extended

Thumb Movements at CMC Joint

• Thumb Flexion/Extension (Radial Adduction/Abduction) – Axis - Anterior/Posterior – Plane – Frontal

• Thumb Palmar Adduction/Abduction– Axis – Lateral– Plane - Sagittal

Thumb Movements

Thumb Movements at CMC Joint

• Flexion/Extension– (Radial AB/Adduction)

• AB/Adduction– (Palmar AB/Adduction)

• Opposition/Reposition

Functional Position of Hand

• Wrist is in 20 to 30 degrees of extension and slight ulnar deviation

• Fingers in 45 degrees of MCP, 15 degrees of PIP and DIP flexion

• Thumb is in 45 degrees of abduction

Intrinsic Plus

• Flexion of MP to 90 degrees and extension at PIP and DIP - or Roof Top Position

• Interossei and lumbricals at their shortest

• Common in patients with R.A.

Intrinsic Minus

• Hyperextension of the MP joints and flexion of the PIP joints or “Clawhand”

• Paralysis of interossei and lumbrical muscles

Intrinsic and extrinsicplus hand

• Intrinsic=(Lumbricals and interosseus =table top)

• Extrinsic=ED, FDS, FDP) = Hook

Intrinsic Plus and Minus

Types of Prehension

• Power grip– Spherical

– Cylindrical

• Precision grip• Power (key) pinch

– Lateral pinch

• Precision pinch• Hook grip

Match

• Power grip– Spherical

– Cylindrical

• Precision grip• Power (key) pinch

– Lateral pinch

• Precision pinch• Hook grip

Common hand disorders

Problems of the Hand

• Intrinsic Tightness

• Nerve injuries– Ulnar Nerve Injury

– Median Nerve Injury• Carpal Tunnel Syndrome

– Radial Nerve Injury

• Tendon injuries– Mallet Finger

– Swan Neck Deformity

– Boutonniere Deformity

– Zig Zag Deformities

– DeQuervain’s Disease

• Fascia– Dupuytren’s Contracture

Bunnell-Lister Test for Intrinsic Tightness

• MCP joint held in slight extension while examiner moves the PIP joint into flexion – if can’t be flexed, intrinsic or joint capsule tightness

• Place MCP joint in a few degrees of flexion to relax intrinsics – if joint can now flex, then it was intrinsic tightness

• If when MCP joint placed in flexion still can’t flex PIP – then it is a joint capsule tightness or contracture.

Bunnell-Lister Test for Intrinsic Tightness: Step 1

• MCP joint held in slight extension will therapist moves the PIP joint into flexion – if can’t be flexed, intrinsic or joint capsule tightness

Bunnell-Lister Test for Intrinsic Tightness: Step 2

• Place MCP joint in a few degrees of flexion to relax intrinsics – if joint can now flex, then it was intrinsic tightness

Bunnell-Lister Test for Intrinsic Tightness: Step 3

• If when MCP joint placed in flexion still can’t flex PIP – then it is a joint capsule tightness or contracture

Musculotaneous nerve (C5, C6 – Continuation of the lateral cord)

Points of entrapment• 1.) Coracoid process

(may be injured during surgery)

• 2.) Coracobrachialis muscle

• 3.) Distal lateral arm as it goes through investing fascia

• 4.) Lateral Forearm – Vulnerable to blunt trauma

Tenodesis- C6• http://video.google.com/videosearch?sourceid=navclient&rlz=1T4ADBF_enUS296US296&q=tenodesis&um=1&ie=UTF-

8&sa=N&hl=en&tab=wv#q=quadriplegia+c6&hl=en&emb=0

Median Nerve Injury

• Unable to oppose thumb

• Unable to make a complete fist

• Atrophy of thenar eminence

• Weak wrist flexion

• Weak pronation of the forearm

Median Nerve = C5-C6, Medial and Lateral cords

1.) Ligament of struthers/supracondylar process (medial ridge)

2.) Bicipital aponeurosis3.) Between 2 heads of pronator

teres (Pronator syndrome)4.) Sublimis Bridge (FDS borders)5.) AIN (Anterior interosseous nerve

branch)- may also be entrapped by pronator

6.) Carpal Tunnel- between flexor tendons and transverse carpal ligament

7.) Metacarpal tunnel – between metacarpal ligaments and MCP’s

Muscles Innervated by the Median Nerve

• Flexor Carpi Radialis • Palmaris Longus• Flexor Digitorum Superficialis• Radial Half of Flexor Digitorum Profundus • Two Radial Lumbricals• Flexor Pollicus Longus • Superficial portion of Flexor Pollicus Brevis• Opponens Pollicus • Abductor Pollicus Brevis (may have ulnar

innervation)

Carpal Tunnel Syndrome

Carpal Tunnel Syndrome – Tinel’s Sign

• Tinel’s Sign – When therapist taps over the carpal tunnel, the client will feel parasthesias or tingling distally

Phalen’s Test• Therapist flexes

client’s wrists manually and holds together for one minute. Positive test elicits tingling in thumb, index finger, and middle and lateral half of the ring finger and is indicative of Carpal Tunnel Syndrome.

Ape Hand Deformity

Median Nerve Injury (ape or pope)

• Low injury = Thumb, index, middle. Loss of 2 lateral lumbricals – Index and middle have

noticeable claw, – Thumb is rotated and

flexed and in same plane as fingers, looses opposition (ape)

High injury = Only FCU and ulnar half of FDP are spared. Similar claw but not as pronounced because don’t have the force of the long flexors. (pope)

Hand is virtually useless

Ulnar nerve- points of entrapment

1.) Arcade of Struthers (as goes into posterior compartment through medial septum)

2.) Posterior to medial epicondyle (on bony floor)

3.) Cubital tunnel – between FCU and medial collateral ligament (cubital tunnel syndrome)

4.) Guyon’s canal – against piso-hamate ligament, from chronic compression (bike rider)

Ulnar nerve injury

More severe deformity with low injury

High injury also loose FDP so fingers are less flexed

Muscles innervated by the Ulnar nerve

• Flexor carpi ulnaris• Medial half of the

flexor digitorum profundus

• Medial two lumbricals,

• Interossei (4 dorsal and 4 palmar)

• Adductor pollicis

• Abductor digiti minimi

• Opponnens digiti minimi

• Flexor digiti minimi• Flexor policis brevis

(also has median innervation)

Ulnar Nerve Injury

• Flexion Deformity of the 4th and 5th fingers (due to paralysis of the lumbricals)

• Atrophy of hypothenar eminence

• Atrophy of interrossei• Atrophy of thumb web space• Difficulty holding a paper

between thumb and index finger

• “Claw Hand”

Froment’s Sign

• Therapist has client hold paper with a lateral pinch

Cubital Tunnel Syndrome

Surgery consists of

a.) "decompression", (removal of the roof or one wall of the tunnel

OR

b.) "transposition" which moves the ulna nerve out of the cubital tunnel to another place.

Radial Nerve- Points of entrapment• Spiral Groove – with

fracture, (Saturday night palsy- when compressed between bone and hard surface)

• Lateral intermuscular septum

• Radial Tunnel• Superficial branch-

(posterior interosseous nerve) – vulnerable to external forces, and as it branches through fascia

Muscles Innervated by the Radial Nerve • Extensor Carpi Radialis Longus

• Extensor Carpi Radialis Brevis

• Extensor Carpi Ulnaris

• Extensor Digitorum

• Extensor Indicis Proprius

• Extensor Pollicus Longus

• Extensor Pollicus Brevis

• Abductor Pollicus Longus

Radial Nerve Injury = Wrist drop or Saturday night palsy

In Axilla- loss of elbow extensors and extensors of the wrist and digits resulting in wrist drop.

There is a sensory loss to a narrow strip of skin on the back of the forearm and on the dorsum of the hand and lateral three and one

half digits.

• Spiral Groove The branches to the triceps are spared in this injury so that extension of the elbow is possible.

• The long extensors of the forearm are paralyzed and this will result in a "wrist drop". There is a small loss of sensation over the dorsal surface of the hand and the dorsla sufaces of the roots of the lateral three fingers.

Radial Tunnel Syndrome

Radial Nerve Injury

• Wrist drop

• Lack of MP extension

• Lack of thumb IP extension

• Lack of thumb abduction

• Grip affected due to lack of wrist extension

Wrist Drop (Radial Nerve Injury)

Mallet Finger

• Tear of the extensor tendon from the attachment on the distal phalanx

Swan Neck Deformity

• MCP joint subluxes volarly and PIP extends as intrinsics contract.

• Is a result of contracture of the intrinsics

Boutonniere Deformity

• Deformity is a result of a rupture of the central tendinous slip of the extensor hood

• Central extensor slip and lateral bands migrate volarly; extends MCP (and DIP) and flexes PIP.

Zig Zag Deformities of the Fingers

Zig Zag Deformity of the Thumb

DeQuervain’s Disease

• Tenosynovitis of thumb “tendons at the radial styloid process– abductor pollicus longus – extensor pollicus brevis

• Maybe a swelling in the area, tenderness

Anatomical Snuff Box

• Abductor pollicus longus

• Extensor pollicus brevis

• Extensor pollicus brevis

Finkelstein Test• Client makes a

fist with thumb “inside” the fist. Therapist stabilizes forearm and ulnarly deviates wrist. Positive sign is pain over the abductor pollicus and extensor pollicus brevis.

Palmar Aponeurosis

• Fascia in the palm of hand

Dupuytren’s Contracture

• Fibrous contracture of the palmar fascia