Lecture 16- Forearm and Hand 2 Flashcards
Label this
- Flexor carpi radialis
- Flexor pollicis longus
- Compartment which contains both tendons of flexor digitorum superficialis, and flexor digitorum profundas
What is the name of the fibrous band at the bottom, and what is the yellow thing in the middle that runs beneath the band
Bottom band is the flexor retinaculum, and the yellow structure is the median nerve
For clinical purposes, what are we calling the same as the flexor retinaculum even though its not?
Transverse carpal ligament
What are the attachments for the flexor retinaculum?
- Tubercle of scaphoid
- Tubercle of trapezium
- Pisiform bone
- Hook of hamate
What are the contents of the carpal tunnel?
Long flexor tendons of digits, and the median nerve
What is the common origin for the extensor muscles of the forearm?
Commin origin is around the lateral epicondyle, and also the posterior surface of ulna and interosseous membrane
What is the extensor of the thumb?
Extensor pollicis longus (forms posterior side of snuff box also)
What extends the index finger, and what extends the 5th finger
Index finger = Extensor indicis, 5th finger = Extensor digiti minimi
Where is the common origin for the flexor muscles of the forearm?
Medial epicondyle
Describe the structure of extensor digitorum
It’s muscle belly is in the forearm, and distally it has four tendons which each act as a main extensor for each finger
What tendons are found in the first extensor compartment?
Tendon of abductor pollicis longus and extensor pollicis brevis
Which tendons lie in the second extensor compartment?
Extensor carpi radialis longus, and extensor carpi radialis brevis
Which tendon is found in the 3rd compartment on the extensor side of the wrist?
Tendon of extensor pollicis longus
Which muscle do the set of 4 tendons in the 4th extensor compartment belong to? And there is one more tendon, what does this belong to?
Extensor digitorum, and in the 4th compartment there is also the extensor indicis
Which tendon lies in the 5th extensor compartment?
Extensor digiti minimi
Which tendon lies in the 6th extensor compartment
Tendon of extensor carpi ulnaris
What three muscles are in the Thenar eminence?
- Flexor pollicis brevis
- Abductor pollicis brevis
- Opponens pollicis
Which muscles belong in the hypothenar eminence?
- Flexor digiti minimi
- Abductor digiti minimi
- Opponens digiti minimi
Which muscle is this?
Adductor pollicis
Excluding the muscles of the thenar and hypothenar eminence, what other intrinsic muscles are there in the hand?
- Adductor pollicis
- Lumbricals and interossei
What is the proximal and distal attachment for the lumbricals?
The lumbricals proximally attach to the tendons of flexor digitorum profundus, and their tendinous slips pass dorsally to attach to the extensor expansion
What is the proximal and distal attachment of the interossei muscle?
The interossei muscle attaches proximally to the metacarpal bones, and distally attaches to the extensor expansion
What movement does the palmar interossei perform, and what movement does the dorsal interossei perform?
- Palmar interossei = adducts fingers (PAD)
- Dorsal interossei = abducts fingers (DAB)
PALMAR INTEROSSEI ARE DEEP TO LUMBRICALS
What are the 5 superficial muscles on the flexor aspect of the forearm?
- Pronator teres
- Flexor carpi radialis
- Palmaris longus
- Flexor digitorum superficialis
- Flexor carpi ulnaris
What are the 3 deep muscles on the flexor aspect of the forearm?
- Flexor pollicis longus
- Flexor digitorum profundas
- Pronator quadratus
*
- Pronator quadratus
Why is compartment syndrome very bad, not healthy, u die
Compartment syndrome is caused by tissue damage, and this leads to the compartment(s) getting swollen causing the nerves and muscles to become compressed. This can cause them to become necrotic, and eventually dying.
What is the key supinator of the eblow when it is at 90 degrees?
Biceps brachii
Describe how force is transmitted in the upper limb
Most of the force is recieved by the second and third metacarpals, and this force is then transmitted via the trapezoid and capitiate, then the scaphoid and lunate, and then the radius, and then the ulna via the interosseus membrane, and then the humerus via the humeroulnar joint
Force transmitted to other metacarpals is transmitted to this central anchoring line due to the orientation of the ligaments connecting the bases of metacarpals and carpal bones
