Chapter 7 - The Wrist and Hand Joints Flashcards
How many bones are in the hand and wrist joints?
How many joints?
How many muscles?
How many are intrinsic (origin and insertion are both inside the hand)
- 29
- > 25
- > 30
- 18
How many of each type of bone are there?
- Carpal bones?
- Metacarpal bones?
- Phalagnes?
- Sesamoid bone?
Carpal: - 8, 2 rows of 4 Metacarpal: - 5 Sesamoid: - Thumb flexor tendon of thumb
What are the 8 carpal bones?
- Scaphoid, lunate, triquetrum, and pisiform (first row): Proximal
- Trapezium, trapezoid, capitate, and hamate (second row): Distal
Scaphoid is the most often injured
- MOI?
- Differential Diagnosis?
- Concerns?
MOI:
- FOOSH
Differential Diagnosis:
- Will look like a wrist sprain
Concerns:
- Non-union: two halves start to move apart and don’t come back together
- Avascular Necrosis: dies b/c it has a very poor blood supply, common w/non-union
Where is the origin for wrist/finger flexors?
Where is the origin for wrist/finger extensors
- Medial side
- Lateral side
What is TFCC?
- Triangular Fibrocartilage Complex
- Articular Disk
- Along medial wrist
What movements do you have at the wrist?
- Flexion and extension, abduction and adduction –> radial deviation and ulnar deviation
What movements do you have at the fingers?
- Flexion and extension
- At the MCP have abduction and adduction
- Middle philange is reference point to differentiate abduction and adduction
What type of joint is the wrist?
- 4 motions –> diarthrodial –> condyloid –> movement in 2 planes without rotation
Where does movement of the wrist primarily occur? Carpals?
- Distal radius and proximal
- Carpals –> scaphoid, lunate, and triquetrum
How many joints does each finger have and what are they?
- Metacarpalphalangeal Joint (MCP)
- Proximal Interphalangeal Joint (PIP)
- Distal Interphalangeal Joint (DIP)
Joint Types
- MCP?
- PIP?
- DIP?
MCP:
- Diarthrodial –> condyloid
PIP:
- Hinge –> ginglymus –> only flexion and extension
DIP:
- Hinge –> ginglymus –> only flexion and extension
How many joints does the thumb have? What are they? And what type are they?
- 2 Joints
- Interphalangeal Joint (IP) and Carpometacarpal Joint (CMC)
IP: - Hinge –> gignlymus –> only flexion and extension
CMC: - Saddle like –> sellar
What are the wrist flexors?
- Flexor carpiadialis
- Flexor caripulnaris
- Palmaris Longus
What are the wrist extensors?
- Extensor carpiradialis longus
- Extensor carpiradialis brevis
- Extensor Carpiulnaris
What are the philanges flexors?
- Flexor digitorum superficialis
- Flexor digitorum profundus
- Flexor pollicis longus
What are the philanges extensors?
- Extensor digitorum
- Extensor indicis
- Extensor digiti minimi
- Extensor pollicis longus (thumb extensor)
- Extensor pollicis brevis (thumb extensor)
What is carpal tunnel syndrome?
- Flexor digitorum superficialis tendons
- Flexor digitorum profundus tendons
- Pressure on median nerve = symptoms = numbness, tingling, burning, or pain
What is the common origin of wrist extensors?
- Lateral Epicondyle
What is the retinaculum?
- Just proximal to the wrist, both anteriorly and posteriorly, prevents bowstringing of our tendons
Flexor Carpi Radialis Muscle
- Origin?
- Insertion?
- Movements?
Origin: - Medial epicondyle of the humerus Insertion: - Base of second and third metacarpal, anterior (palmar surface) Movements: - Flexion of the wrist - Abduction of the wrist - Weak flexion of the elbow - Weak pronation of the forearm
Palmaris Longus Muscle
- Origin?
- Insertion?
- Movements?
Origin: - Medial epicondyle of humerus Insertion: - Palmaris aponeurosis of second, third, fourth, and fifth metacarpals Movements: - Flexion of the wrist - Weak flexion of the elbow
Flexor Carpi Ulnaris Muscle
- Origin?
- Insertion?
- Movements?
Origin:
- Medial epicondyle of humerus, posterior aspect of proximal ulna
Insertion:
- Pisiform, hamate, and base of fifth metacarpal
Extensor Carpi Ulnaris Muscle
- Origin?
- Insertion?
- Movements?
Origin:
- Lateral epicondyle of humerus
- Middle 2/4 of the posterior border of the ulna
Insertion:
- Base of fifth metacarpal (dorsal surface)
Movements:
- Extension of wrist
- Adduction of wrist together with flexor carpi ulnaris muscle
- Weak extension of elbow
Extensor Carpi Radialis Brevis
- Origin?
- Insertion?
- Movements?
Origin: - Lateral epicondyle of humerus Insertion: - Base of third metacarpal Movements: - Extension of wrist - Abduction of wrist - Weak flexion of elbow
Extensor Carpi Radialis Longus Muscle
- Origin?
- Insertion?
- Movements?
Origin:
- Lower 1/3 of the lateral supracondylar ridge of humerus and lateral epicondyle of the humerus
Insertion:
- Base of second metacarpal (dorsal surface)
Movements:
- Extension of wrist
- Abduction of wrist
- Weak flexion of elbow
- Weak pronation to neutral from a fully supinated position
Flexor Digitorum Superficialis Muscle
- Origin?
- Insertion?
- Movements?
Origin:
- Medial epicondyle of the humerus. Ulnar head: medial coronoid process. Radial head: upper 2/3 of anterior border of the radius
Insertion:
- Split tendons attach to sides of middle phalanx to four fingers
Movements:
- Flexion of fingers at MCP and PIP joints
- Flexion of the wrist
- Weak flexion of elbow
Flexor Digitorum Profundus Muscle
- Origin?
- Insertion?
- Movements?
Origin:
- Proximal 3/4 of anterior and medial ulna
Insertion:
- Base of distal phalanxes of the four fingers
Movements:
- Flexion of 4 fingers at MCP, PIP, and DIP joints
- Flexion of wrist
Flexor Pollicis Longus Muscle
- Origin?
- Insertion?
- Movements?
Origin: - Middle anterior surface of radius and from the anterior medial border of ulna just distal to coronoid process Insertion: - Base of distal phalanx of thumb Movements: - Flexion of thumb at CMC, MCP, and IP joints - Flexion of wrist - Abduction of wrist
Extensor Digitorum Muscle
- Origin?
- Insertion?
- Movements?
Origin: - Lateral epicondyle of humerus Insertion: - Four tendons to bases of middle and distal phalanges of four fingers Movements: - Extension of 2nd, 3rd, 4th, and 5th phalanges at MCP joints - Extension of wrist - Weak extension of elbow
Extensor Indicis Muscle
- Origin?
- Insertion?
- Movements?
Origin:
- Middle to distal 1/3 of posterior ulna
Insertion:
- Base of middle and distal phalanxes of second phalange
Movement:
- Extension of the index finger at MCP joint
- Weak wrist extension
- Weak supination of forearm from a pronated position
Extensor Digiti Minimi Muscle
- Origin?
- Insertion?
- Movements?
Origin: - Lateral epicondyle of humerus Insertion: - Base of middle and distal phalanxes of fifth philange Movements: - Extension of little finger at MCP joint - Weak wrist extension - Weak elbow extension
Extensor Pollicis Longus Muscle
- Origin?
- Insertion?
- Movements?
Origin:
- Posterior lateral surface of lower middle ulna
Insertion:
- Base of distal phalanx of thumb
Movement:
- Extension of thumb at CMC, MCP and IP joint
- Extension of wrist
- Abduction of wrist
- Weak supination of forearm from a pronated position
Extensor Pollicis Brevis Muscle
- Origin?
- Insertion?
- Movements?
Origin: - Posterior surface of lower middle radius Insertion: - Base of proximal phalanx of thumb Movements: - Extension of thumb at CMC and MCP joints - Weak wrist extension - Wrist abduction
Abductor Pollicis Longus Muscle
- Origin?
- Insertion?
- Movements?
Origin: - Posterior aspect of the radius and midshaft of ulna Insertion: - Base of first metacarpal Movements: - Abduction of thumb at CMC joint - Abduction of wrist - Extension of thumb at CMC joint - Weak supination of forearm from a pronated position - Weak flexion of wrist
Intrinsic Muscles of Hand (That we need to know)
- Thenar eminence - 1st metacarpal
- Hypothenar eminence - 5th metacarpal
Wrist Flexion
- Muscles?
- Flexor carpi radialis
- Flexor carpi ulnaris
- Palmaris longus
- Flexor digitorum superficialis
- Flexor digitorum profundus
- Flexor pollicis longus
Wrist Extension
- Muscles?
- Extensor carpi radialis longus
- Extensor carpi radialis brevis
- Extensor carpi radialis ulnaris
- Extensor digitorum
- Extensor indicis
- Extensor digiti minimi
- Extensor pollicis longus
- Extensor pollicis brevis
Wrist Abduction (radial deviation, radial flexion) - Muscles?
- Flexor carpi radialis
- Extensor carpi radialis longus
- Extensor carpi radialis brevis
- Abductor pollicis longus
- Extensor pollicis longus
- Extensor pollicis brevis
Wrist Adduction (ulnar deviation, ulnar flexion) - Muscles?
- Flexor carpi ulnaris
- Extensor carpi ulnaris
Philangeal Flexion
- Muscles?
- Flexor digitorum superficialis
- Flexor digitorum profundus
- Flexor pollicis longus
Philangeal Extension
- Muscles?
- Extensor digitorum
- Extensor indicis
- Extensor digiti minimi
- Extensor pollicis longus
- Extensor pollicis brevis
