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OTA 130 - Kinesiology > Wrist and Extrinsic Hand > Flashcards

Flashcards in Wrist and Extrinsic Hand Deck (67)
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Intrinsic vs. Extrinsic

Intrinsic: Hand muscles originate AND insert within the hand.

Extrinsic: Hand muscles originate in the ARM, and insert in the hand. (Involve the wrist, since they cross it.)


Wrist Joint

• Called the “Radiocarpal Joint”; at distal end of radius
• Includes the Carpal Bones (Scaphoid, Lunate and Triquetrum)
• Condyloid Joint
• Biaxial (flex/extend in sagittal, ulnar/radial deviation in frontal)


Bony Landmarks of the Hand/Wrist

• Radial Styloid (bump in wrist below base of thumb)
• Pisiform Bone (above wrist, at base of ulnar side of hand)
• Ulnar Styloid (bump in wrist below base of pinky)


Order of BONES in Hand (Types)

From Wrist to Fingertips:
• Carpal Bones
• Metacarpals
• Phalanges


Order of Wrist/Hand JOINTS

From Wrist to Fingertips:
• Radiocarpal Joint (wrist)
• Carpometacarpal Joint (CMC)
• Metacarpophalangeal Joint (MCP)
• Proximal Interphalangeal Joint (PIP)
• Distal Interphalangeal Joint (DIP)


Carpal Bones (Proximal Row)

(From Radial to Ulnar)
• Scaphoid
• Lunate
• Triquetrum
• Pisiform
(“So Long To Pinky”) – Pisiform=Pinky side


Carpal Bones (Distal Row)

(From Ulnar to Radial)
• Trapezium
• Trapezoid
• Capitate
• Hamate
(“Here Comes The Thumb”) – Trapezium=Thumb side


Motion at Radiocarpal Joint

(Note: there is no “normal”-varies by person, and even by which hand!)
• Flexion = 0-60˚
• Extension = 0-60˚
• Radial Deviation = 0-20˚
• Ulnar Deviation = 0-30˚



Wrist’s ability to make a circular movement. This is NOT an independent motion of the wrist, but a COMBINATION of all four movements.


Wrist Flexors

All originate at the medial epicondyle.
• Flexor Carpi Ulnaris
• Flexor Carpi Radialis
• Palmaris Longus (missing in 21% of ppl)


Wrist Extensors

All originate at the lateral epicondyle.
• Extensor Carpi Radialis Longus
• Extensor Carpi Radialis Brevis
• Extensor Carpi Ulnaris


Wrist Radial Deviator Muscles

• Flexor Carpi Radialis
• Extensor Carpi Radialis Longus


Innervations of Wrist

1) Radial Nerve (muscles on dorsal surface)
2) Median Nerve (muscles on thumb side)
3) Ulnar Nerve (muscles on ulnar side)


Main Ligaments of the Wrist

1) Radial Collateral Ligament (attaches from radius to scaphoid and trapezium)*
2) Ulnar Collateral Ligament (attaches from ulna to pisiform and triquetrum)*
• *Above 2 provide LATERAL and MEDIAL support.
3) Palmar Radiocarpal Ligament (tough lig that limits wrist extension. Attaches from anterior surface of distal radius and ulna to the proximal carpal bones; prone to sprain)
4) Dorsal Radiocarpal Ligament (Less dense/strong as palmar, limits flexion. Attaches posterior surface of distal radius to proximal carpal bones)


Extrinsic Motions of the Hand

(motions caused by extrinsic muscles)
• Finger Flexion
• Finger Extension
• Thumb Radial ABduction
• Thumb Flexion


Main Ligaments of the Hand

*All hold muscles together/bound to the wrist during motions.

1) Flexor Retinaculum Ligament (Band of connective tissue crossing wrist/hand on anterior side. Contains finger flexor tendons during wrist flexion.)
2) Extensor Retinaculum Ligament (Similar connective tissue crossing wrist on posterior side. Contains extensor finger tendons close to hand during wrist extension.)
3) Transverse Carpal Ligament/Flexor Retinaculum (Forms carpal tunnel.)
4) Palmar Carpal Ligament (More proximal and superficial.)


Extrinsic Muscles of the Hand

1) Extensor Digitorum (extends all finger joints)
2) Extensor Digiti Minimi (extends pinky)
3) Extensor Indicis (extends all joints of index finger)
4) Flexor Digitorum Superficialis (flexes PIP joints)
5) Flexor Digitorum Profundus (flexes all finger joints, but DIP would not flex without it)


Joints of the Thumb

(Proximal to Distal):
1) Carpometacarpal (CMC): trapezium articulates with 1st metacarpal. Has 3 degrees of freedom/6 motions (flex, ext, aBd, aDd, opposition, reposition)
2) Metacarpophalangeal (MCP): flex/ext
3) Interphalangeal (IP): flex/ext


Extrinsic Muscles of the Thumb

1) Extensor Pollicis Brevis: extends CMC and MCP joints
2) Extensor Pollicis Longus: extends all joints of thumb


Anatomical Snuff Box

Triangle on radial side of hand between wrist and thumb. Formed by:
• Abductor Pollicis Longus
• Extensor Pollicis Brevis
• Extensor Pollicis Longus


Innervations of the Thumb

1) Radial Nerve (Extensors and abductor pollicis longus)
2) Median Nerve (Flexor pollicis longus)


Innervations of the Fingers

1) Radial Nerve (Extensors)
2) Median Nerve (Flexor Digitorum Superficialis)
3) Median and Ulnar Nerves (Flexor Digitorum Profundus)


Conditions of Extrinsic Wrist and Hand (List)

1) de Quervain’s Disease /Washer woman’s syndrome
2) Distal Radial Fracture
3) Triangular Fibrocartilage Complex Tear
4) Fractures of Scaphoid


deQuervain’s Disease

• Also called Tenosynovitis or “Washer Woman’s Syndrome”
• Inflammation of Tendon Sheath in wrist
• Affects APL, EPB, EPL
• Caused by repetitive movements of wrist and thumb
• Doc uses “Finkelstein Test” to diagnose (see if pain when flexing thumb in ulnar deviation)


Finkelstein Test

Used to determine if someone has Tenosynovitis (deQuervain’s Disease). Checks for pain when thumb is put into flexion over palm while hand ulnar deviates.


Distal Radial Fracture

Caused by fall on outstretched hand (FOOSH), with wrist extended. (Also called a Colle’s Fracture.)


Colle’s Fracture vs. Smith’s Fracture

Colle’s Fracture = when wrist is extended (dorsal fracture of radius)

Smith’s Fracture = when wrist is flexed (ventral fracture of radius) *Less common.


Goniometry of Wrist

• Use ulnar side of hand to eliminate thumb.
• Palpate to find bony landmarks.
• Line goni to arm/ulna bone and metacarpal of hand.
• Fulcrum at ulnar styloid.

• Center goni over carpal bones (dorsal)
• Use middle finger tendon (extensor dig. long.)
• Ignore fingers! Only use metacarpals!


MMT of Wrist

• One hand holds forearm for support, other is at palm of hand (distal to wrist)

• Move to ulnar/radial sides to do deviations.
• Go inside the thumb to eliminate it from test


Avascular Necrosis (AVN)

Death of bone tissue.

(A scaphoid fracture can cause AVN depending on the location of the fracture within the scaphoid bone. Carpal bones do not have good blood supply because of the articular cartilage they are covered in.)