Chapter 13 (Hand) Flashcards
What bones is the hand composed of?
- Thumb -Fingers
- Metacarpals - Phalanges
What are the 3 joints of the thumb?
- Carpometacarpal (CMC)
- Metacarpophalangeal (MCP)
- Interphalangeal (IP)
What are the motions of the thumb?
- Extension -Flexion
- Opposition - Adduction
- Abduction
Name the digits (fingers) (2-5)
2nd = Index 3rd= middle 4th= ring 5th= little finger
What are the 4 joints of the hand?
- Carpometacarpal
- Metacarpophalangeal
- Proximal interphalangeal
- Distal interphalangeal
Describe the carpometacarpal joint
- Nonaxial plane
- No motion
- Digits 2-5
Describe the metacarpophalamgeal joint
- Biaxial (moves in 2 planes)
- Knuckles
- flexion, extension (sag. plane)
- Abduction (frontal plane)
Describe the interphalangeal joint (proximal +distal)
- two interphalangeal joints in fingers (2-5)
- Uniaxial, hinge joint
- Flexion, extension
How many phalanges does the thumb and fingers each have?
thumb = 2 phalanges fingers= 3 phalanges
What are some of the most common ligaments/structures of the hand?
- Flexor Retinaculum
- Palmer carapal ligament
- Transverse carpal ligamnets
- Extensor retinaculum
- Extensor retinaculum ligaments
-This ligament a fibrous band that spans over the anterior wrist. -Has 2 parts: palmar carpal/transverse carpal ligament.
Flexor Retinaculum
This ligament is usually cut to get rid of carpal tunnel syndrome
Transverse carpal ligament
This ligament a fibrous band transversing the wrist on the posterior side. -Holds the extensor tendons to the wrist.
Extensor retinaculum ligament
Why are there acrhes in the hand?
Due to how the bones sit, the functional movement, and ability of thumb opposition.
Extrinsic
- Proximal attachment proximal to the wrist
- Assistive role in wrist function
- Primary func. at thumb or fingers
O= Outside the wrist I= Inside the hand Role= Move fingers
Extrinsic
Intrinsic
- Proximal attachment at or distal to the carpal bones
- For fine motor control. precision movement of the hand
- Functions at thumb or fingers
- Thenar, hypothenar
O+I = Inside the hand
Intrinsic
Name some extrinsic anterior muscles
- Flexor digitorum superficialis
- Flexor digitorum profundus
- Flexor pollicis longus
Name some extrinsic posterior muscles
- Extensor digitorum
- Extensor digiti minimi
- Extensor indicis
- Abductor pollicis longus
- Extensor pollicis longus
- Extensor pollicis brevis
What is the origin, insertion and action of the flexor digitorum superficialis muscle?
O= medial epicondyle of humerus I= middle phalanx 2-5 A= MCP/PIP joint flexion, assists with wrist flexion
What is the origin, insertion and action of the flexor digitorum profundus muscle?
O= Ulna I= Distal phalanx 2-5 A= Flexes all 3 finger joints (MCP, PIP, DIP)
What is the origin, insertion and action of the extensor digitorum muscle?
O= Lateral epicondyle of humerus I= Distal phalanx 2-5 A= Extends all 3 finger joints (MCP, PIP, DIP)
What is the origin, insertion and action of the extensor indicis muscle?
O= Ulna I= Distal phalanx of 2nd finger A= Extends all 3 joints of 2nd finger(MCP, PIP, DIP)
What is the origin, insertion and action of the extensor digiti minimi muscles?
O= Lateral epicondyle of humerus I= distal phalanx 5th finger A= Extends all 3 joints of 5th finger (MCP, PIP, DIP)
What is a common latin term for thumb?
Pollicis
What are some extrinsic thumb muscles?
- Flexor pollicis longus
- Abductor pollicis longus
- Extensor pollicis longus
- Extensor pollicis brevis
What is the origin, insertion and action of the flexor pollicis longus muscle?
O= radius I= Distal phalanx thumb A= Flexes all 3 joints of thumb (CMC, MCP, IP)
What is the origin, insertion and action of the abductor pollicis longus muscle?
O= Radius I= 1st metacarpal A= Abducts thumb (CMC)
What is the origin, insertion and action of the extensor pollicis brevis muscle?
O= Radius I= Thumb A= Extends CMC, MCP joints of thumb
What is the origin, insertion and action of the extensor pollicis longus muscle?
O= Ulna I= Thumb A= Extends all 3 joints of the thumb (CMC, MCP, IP)
What are the 2 intrinsic muscles of the hand?
- Thenar
2. Hypothenar
Chunk of tissue at the base of the thumb (moves thumb)
Thenar
Bulk of tissue on the ulnar side of hand
Hypothenar
What are 2 types of grasps?
- Power grips
2. Precision grips
This type of grasp is used when objects need to be held forcefully while being moved. Whole hand grasp.
Power grip
This type of grasp is used when an object needs to be manipulated. Finer type of movement. Uses the thumb and finger tips.
Precision grip
What type of grasp is used to hold a hammer or using a door knob?
Power grip
What type of grasp is used to hold a pen or thread a needle?
Precision grip
Power Grip: Cyclindrical grip
- All fingers flexed around a object
- Ex. Holding a hammer, racquet, bottle, wheelbarrow
Power Grip: Spherical grip
- All fingers and thumb adducted around an object
- Fingers spread apart, palm not involved
- Ex. Picking up a glass by its top, holding an apple or doorknob
Power Grip: Hook grip
- 2nd-5th fingers flexed around an object in a hooklike manner
- Thumb not usually involved
- Ex. Holding onto a handle like a suitcase, wagon, bucket
Precision Grip: Pad-to-pad —> Pinch grip
- MCP and PIP joints/fingers flexed
- Thumb and index finger
Precision Grip: Pad-to-pad—> Three-jaw chuck
- Involves thumb, index, middle fingers
- Ex. Holding a pen
Precision Grip: Pad-to-side –> Lateral Prehension
- Thumb pressed up on side of the index finger
- Ex. Holding a key
Precision Grip: Side-to-side
- Similar to pad-to-side grip
- Req. adduction of 2 fingers (index or middle)
- Weak grip
- Ex. Holding a cigarette or pencil
