Forearm and Hand Flashcards
What are the functions of the hand
- Grasp
- Sensation for touch
- Communicagtion during expression
The ______ side of the palm: Skin tighter because of fat pads underneath the skin and the thicker dermis; Many sweat glands, but no hair or sebaceous glands
The ______ side of the hand:
Loose skin; Also has hair
Volar (palmar) surface; dorsal of hand
Lateral volar aspect of palm; 3 muscles involved in movement of thumb
Thenar eminence
Medial volar aspect of palm; 3 muscles involved in movement of little finger
Hypothenar eminence
What bones doe the radius and ulna always articulate with?
Scaphoid and lunate
What are the are the components of the radiocarpal joint?
- Radius and articular disc Carpal bones: - Scaphoid - Lunate - Triquetrum during hand adduction
What carpal bones of the radiocarpal joint are not included in the synovial capsule?
- Triquetrum
2. Pisiform
What type of joint is the radiocarpal joint? What are the actions?
Condyloid type synovial (biaxial); Flexion/extension, Abduction/adduction, Circumduction
What are in the superficial layer of the hand, lateral to medial?
- Flexor carpi radialis
- Palmaris longus
- Flexor digitorum superficialis
- Flexor carpi ulnaris
What are in the deep layer of the hand, proximal to distal?
- Flexor digitorum profundus
2. Flexor pollicis longus
Joint between the proximal and distal rows of carpal bones; Part of wrist flexion/extension occurs at this joint; Can evaluate by stabilizing radiocarpal or intercarpal joint and looking at movement
Inter carpal joint
What type of joint is the intercarpal joint?
Arthrodial (gliding/planar) joints
What type of joint is the carpal-metacarpal joint of the thumb?
Saddle-type synovial join
What are the carpal-meta carpal joints for fingers 2-5?
Planar type synovial joint
What joint type are the metacarpophalangeal joints?
Condyloid synovial joint
What joint type are the interphalangeal joints?
Hinge-type synovial joints
In the carpal arch, the lateral pillar of the arch is made of? the medial pillar is made of?
- Ridge of the trapezium
- Scaphoid;
- Hook of the hamate
- Pisiform
Holds the carpal arch in place (keeps it from flattening); attachment sites are lateral pillar and medial pillar; concave anteriorly
Flexor retinaculum
AKA transverse carpal ligament
What is superficial to the flexor retinaculum?
- Palmaris longus muscle
- Ulnar nerve and blood vessels
- Branch of median nerve that supplies the skin of the proximal palm
What goes through the flexor retinaculum?
- Flexor carpi radialis – through the flexor retinaculum to 2nd and 3rd metacarpal bones
- Flexor carpi ulnaris – merges into the flexor retinaculum to attach to pisiform, hamate and 5th metacarpal
What is deep to the flexor retinaculum?
- Tendons of FDP - dee
- Tendons of FDS
- Tendon of FPL
- Median nerve
What tendons are around the extensor expansion?
- FDS
2. FDP
What tendons make up the extensor expansion or attach to it?
- Lumbrical tendons
- Interossei tendons
- Extensor digitorum tendons
What are the functions of the extensor expansion?
- Permits MCP extension with IP extension
- Permits MCP extension with IP joints in flexion
- Permits MCP flexion with the joints in extension
- Full extension of the fingers requires the intrinsic muscles of the hand to perform IP extension
- Full flexion of the fingers in their complete range requires the intrinsic musculature working through the extensor expansion to produce MCP flexion
What is the anterior border of the snuff box? Posterior border?
Anterior border:
1. Tendon of the abductor pollicis longus
2. Tendon of the extensor pollicis brevis
Posterior border:
1. Tendon of the extensor pollicis longus
What is contained in the snuff box?
- Scaphoid bone
- Trapezium bone
- Radial artery
What branch of the brachial plexus does the radial nerve come off of?
In the arm, the radial n. is in the _____ compartment and travels _____. At the elbow, it moves into the ____ compartment, travels between the brachial and brachioradialis, then divides into _____ and ____ branches
posterior; distolateral; anterior; superficial; deep
The deep radial nerves supplies muscles and joints. It pierces the ____ muscle and enters the _____ compartment
Supinator; posterior
What is the terminal branch of the deep radial nerve?
posterior interosseous nerve
The superficial radial nerve is purely _____. It travels with; the ______.
Cutaneous; radial artery
Which part of brachial plexus?
In arm, it supplies no muscles.
In the elbow, it branches to _____ and crosses in the ____ plane. Passes between the two heads of the pronator teres muscle.
Medial and lateral cord; elbow joint capsule; anteromedian
What is tendons run through the groove on the lateral surface of the styloid process of the radius?
- Abductor pollicis longus
2. Extensor pollicis brevis
What type of joint is the humero-ulnar joint?
Hinge synovial joint
Where does the humero-ulnar joint articulated (specifically)?
Between the trochlea of the humerus and the semilunar (trochlear notch) of the ulna
What type of joint is the humero-radial joint?
Gliding (arthrodial, planar) synovial joint
What type of joint is the proximal radio-ulnar joint?
Pivot-type synovial joint
What are the articulations of the proximal radio-ulnar joint
- Circumference of the head of the radius
- radial notch on the lateral surface of the ulna
Strong band between proximal ulna and radius; Attaches to anterior and posterior margins of radial notch on ulna; Completely encircles head of the radius
Annular lig
- distal fibers are shorter to help hold the head of the radius and prevent inferior displacement
Band of tissue from base of coronoid process on the ulna to the radial tuberosity
Oblique cord
What type of joint is the middle radio-ulnar joint?
Syndesmosis type joint
- made of interosseous membrane and oblique cord
What type of joint is the distal radio-ulnar joint? what are its articulations?
Pivot type synovial
- head of ulna and the ulnar notch on the radius
What causes the volar skin to crease?
Creases where skin is very adherent to deeper structures
Fibers circle the MCP joint anchoring the extensor expansion to the palmar ligament or plate
The hood of the dorsal digital expansion AKA extensor expansion
Where does the central band of the extensor expansion inset to? the lateral bands?
- base of the middle phalanx
- travel on both sides of the PIP joint, rejoin over the middle phalanx, and insert on the base of the distal phalanx
What tendons help form the lateral bands of the extensor expansion?
Lumbricals and interossei muscles
What are the muscles of the superficial layer of flexors of the forearm from lateral to medial?
- Pronator Teres
- Flexor Carpi Radialis
- Palmaris Longus
- Flexor Carpi Ulnaris
What are the muscle makes up the middle layer of flexors of the forearm?
Flexor digitorum superficialis
What are the muscles of the deep layer of flexors of the forearm?
- Flexor digitorum profundus
- Flexor pollicis longus
- Pronator quadratus
What are the muscles of the superficial layer of extensors of the forearm from lateral to medial?
- Brachioradialis
- Extensor Carpi Radialis Longus
- Extemspr Carpi Radialis Brevis
- Extensor Digitorum
- Extensor Digiti Minimi
- Extensor Carpi Ulnaris
- Anconeus
What are the muscles of the deep layer of extensors of the forearm from proximal to distal?
- Supinator
- Abductor Pollicis Longus
- Extensor Pollicis Longus
- Extensor Pollicis Brevis
- Extensor Indicis
