UPPER LIMB 2 Flashcards
Anterior compartment of the forearm
- Significantly FLEXES at wrist joint
- BRACHIORADIALIS - lateral
(radial n.) - PRONATOR TERES
(median n. - c6,c7) - FLEXOR CARPI RADIALIS
(median n. - c6, c7)
+PALMARIS LONGUS
(median n. - c7, c8)
- FLEXOR DIGITORUM SUPERFICIALIS
(median n. - c7, c8, t1)
+FLXOR DIGITORUM PROFUNDUS
- FLEXOR CARPI ULNARIS
(ulnar n. - c7, c8)
Interesting innervation of flexor digitorum profundus
Ulnar nerve supplies the ulnar half (C8 and T1)
Median nerve supplies the radial half.
Movements of anterior compartment of the forearm
- Significantly FLEXES at wrist joint
Brachioradialis supinates
Pronator Teres pronates
Flx. C. Radialis = Radial deviation (abducts)
Flx. C Ulnaris = Ulnar deviation (adducts)
Actions of Flexor digitorum superficialis
Flexes the proximal interphalangeal (PIP) and metacarpophalangeal (MCP) joints as well as the wrist joint.
CANNOT FLEX DIP.
Actions and significance of Flexor digitorum profundus
Flexes the distal interphalangeal (DIP), proximal interphalangeal (PIP) and metacarpophalangeal (MCP) joints of the fingers and also the wrist joint.
+The lumbricals arise from the tendons of flexor digitorum profundus.
What is the common origin of the anterior compartment?
Medial epicondyle acts as common superficial and intermediate flexor origin
Where do the tendons of FDSuperficialis insert?
Attach. to the middle phalanx of the INDEX, LONG, RING, AND SMALL fingers.
What n innervates FDS?
Median N (C7-T1)
What n innervates Brachioradialis?
Radial N (C5-C7)
Deep Anterior Forearm Muslces
- FLEXOR DIGITORUM PROFUNDUS
(Ulnar nerve (C7,C8) supplies the ulnar half.
Median nerve (C8 and T1) supplies the radial half.)
2. FLEXOR POLLICIS LONGUS Median nerve (C8, T1).
- PRONATOR QUADRATUS (deepest)
(Median nerve (C8, T1))
What is the action of the Flexor Pollicis Longus?
Flexes the interphalangeal (IP) and metacarpophalangeal (MCP) joints of the thumb.
What is the action. of the FDP?
Flexion of
- distal interphalangeal (DIP),
- proximal interphalangeal (PIP)
- metacarpophalangeal (MCP)
joints of the fingers and also the wrist joint.
Significance of the Flexor Retinaculum
Forms roof of carpal tunnel, significantly binds down passing tendons, preventing bow-stringing upon muscle contraction
What is the innervation of the pronator quadratus?
(Median nerve (C8, T1))
What is the innervation of the FDP?
Ulnar for ulnar half (C7, C8)
Median N. for radial. half (C8-T1)
What is the innervation of the Flexor Pollicis Longus
Median nerve (C8, T1).
What nerve passes betwen FDS and FDP?
Median N.
Which forearm artery gives rise to the superficial palmar arch?
Ulnar artery
Course of the Radial Artery
Continues as the deep palmar arch
Most superficial palmar structures and significance
- PALMAR FASCIA
= protect underlying deep muscles and neurovasc.
+ contnuaton of palmaris longus if present
- FLEXOR RETINACULUM
Thenar Muscles
*Thenar eminence, lateral aspect of palm
- ABDUCTOR POLLICIS BREVIS - lateral
(Median nerve (C8, T1)) - FLEXOR POLLICIS BREVIS
(Median nerve.
Ulnar nerve (C8, T1) - deep belly) - OPPONENS POLLICIS BREVS - deep
(Median nerve (C8, T1))
Which nerve segment from the brachial plexus serves to provide. majority of the thenar innervation?
C8
Hypothenar Muscles
*Medial fleshy belly of the balm
- ABDUCTOR DIGITI MINIMI - lateral
(Ulnar nerve (C8, T1, deep branch)) - FLEXOR DIGITI MINIMI
(Ulnar nerve (C8, T1)) - OPPONENS DIGITI MINIMI
(Ulnar nerve (C8, T1))
Significance of the flexor retinaculum as origins for certain intrinsic muscles
Gives off Thenar and Hypothenar Muscles (eminences either side of the hand)
Central Compartment Contents and Significance
*Contain flexor tendons passing from forearms to digits
- FLEXOR DIGITORUM SUPERFICIALIS
(Median nerve (C7, 8 and T1)) - FLEXOR DIGITORUM PROFUNDUS
(Ulnar nerve supplies the ulnar half.
Median nerve (C8 and T1) supplies the radial half) - FLEXOR POLLICIS LONGUS
(Median nerve (C8, T1)) - LUMBRICALS - arise from medial and lateral aspects of the FDP tendon
(Median nerve (C8, T1))
Actions and innervations of the LUMBRICALS
FLEXION @ MCPhalangeal Joint
EXTENSION @ IP joint
2nd to 5th digits
Medial Lumbricals (ULNAR N.) Lateral Lumbricals (RADIAL N.)
ADDUCTOR COMPARTMENT
INFERIOR TO FLEXOR POLLICIS LONGUS
- ADDUCTOR POLLICIS
(Ulnar nerve (C8, T1))
Made up of (coming from middle finger):
- OBLIQUE HEAD
- TRANSVERSE HEAD
Significance of Interossei
- PALMAR INTEROSSEI = ADDUCTION
(Ulnar nerve) - DORSAL INTEROSSEI = ABDUCT
(Ulnar nerve)
PAD, DAB
Which spinal segment contributes the most to the innervation of the interossei?
C8 + T1
Significance of the neurovasculature of the hand (anterior)
- Superior Palmar Arch visble but deep is not as it lies inferior. to muscles etc.
- Ulnar n travels. w/ palmar digital branch and innervates 4th and 5th fingers
- Medial n.
Under the flexor retinaculum the median nerve divides into five digital branches that run distally through the palm
The digital branches run along the medial and lateral aspects of the 1st, 2nd and 3rd fingers and the lateral aspect of the 4th finger.
The ulnar nerve is a branch of which cord of the brachial plexus?
Medial Cord
What type of joint is the distal radio-ulnar joint?
pivot type synovial joint
Identifying radius, ulnar, and bones of the hand
Radial stylus, radius larger than ulna.
- Radius articulates with scaphoid and lunate
What sits between the ulna and the carpal bones?
triangular fibrocartilage complex (TFCC) connects the bones in your forearm with bones in your wrist.
Contents of the posterior forearm: acting on. hands and wrist
- EXTENSION
- origin: lateral epicondyle / lateral supracondyle
- EXTENSOR CARPI RADIALIS LONGUS - supracondylar ridge origin
(Radial nerve (C6, 7)) - EXT. CARPI RADIALIS BREVIS
(Radial nerve (C7, 8)) - EXTNSOR CARPI ULNARIS
( Radial nerve (C7, 8))
deeper
4. SUPINATOR
(Radial nerve (C5, 6))
What is the action of EXT. CARPI RADIALIS LONGUS?
Abduction and extenson of the wrist joint
Contents of the posterior forearm: acting on digits
- EXTENSOR DIGITORUM
(Radial nerve (C7, 8)) - EXTENSOR DIGITI MINIMI
(Radial nerve (C7, 8))
--- deeper 3. EXTENSOR INDICIS ---- thumb action 4. ABDUCTOR POLLICIS LONGUS - lateral
- EXT. POLLICIS BREVIS
- EXT. POLLICIS LONGUS - medial
(radial n. - C7, C8)
Course of the radial n. and its significance in the posterior compartment
Wthin the posterior forearm, after exiting cubital fossa =
SUPERFICIAL BRANCH
* purely sensory; distributed to skin on dorsum of hand, passes over anatomical snuffbox
DEEP BRANCH = POSTERIOR INTEROSSEUS N.
- main motor nerve
- pierces supinator to enter extensor compartment
Arterial Supply of the posterior forearm
POST. INTEROSSEUS ART. (ULNAR ART.)
RECURRENT INTEROSSEOUS ART. (ULNAR ART.)
Significance of synovial cysts
Occur at. dorsal sheaths, associated w/ carpal tunnel, which the EXTENSOR RETINACULUM acts as a floor of.
