Bio 502, Fall, 2016, Lecture #12: Intrinsic hand

Card Set Information

Author:
ChathamBio502
ID:
242681
Filename:
Bio 502, Fall, 2016, Lecture #12: Intrinsic hand
Updated:
2016-10-27 10:58:57
Tags:
intrinsic hand
Folders:

Description:
hand stuff
Show Answers:

Home > Flashcards > Print Preview

The flashcards below were created by user ChathamBio502 on FreezingBlue Flashcards. What would you like to do?


  1. Which muscles would you recruit to manually express how you're feeling these days?
    • hmmm...perhaps extensor digitorum of the 3rd digit and
    • -flexor digitorum profundus of digits 2, 4 and 5
    • flexor digitorum superficialis of digits 2, 4 and 5
    • -flexor pollicis longus, flexor pollicis brevis, adductor pollicis
  2. Which components of the wrist participate in the wrist joint proper (radiocarpal joint)?
    • The distal radius
    • the scaphoid
    • the lunate
    • the triquetrum
    • the articular disc of the distal ulna
  3. What type(s) of bone is the pisiform?
    seasmoid & short bone
  4. Which ligaments are most likely implicated in wrist instability during palmarflexion?
    Palmar ulnocarpal and ulnar collateral
  5. For the following question select one of the following pick:
    A) if ALL of the options are FALSE
    B) if ALL of the options are TRUE
    C) if ii and iii are true
    D) if iii and iv are true
    E) if iii, iv, and v are true

    i. there is a positive correlation between dorsiflexion and ulnar deviation.
    ii. dorsiflexion takes place primarily at the midcarpal joint
    iii. the radial styloid process inhibits radial deviation.
    iv. adduction takes place primarily at the lateral carpal joint
    v. Average adduction is <35 degrees
    C
  6. For the following question select one of the following pick:
    A) if ALL of the options are FALSE
    B) if ALL of the options are TRUE
    C) if ii and iii are true
    D) if iii and iv are true
    E) if iii, iv, and v are true

    i. The palmar ligament is the strongest ligament of the carpometacarpal joint.
    ii. The 5th carpometacarpal joint is the least mobile of the carpometacarpal joints in the hand.
    iii. Neither medial nor lateral rotation at the MCP joints can occur in isolation.
    iv. The finger digits laterally rotate at the IP joints during flexion.
    v. the thumb medially rotates during flexion.
    E
  7. For the following question select one of the following pick:
    A) if ALL of the options are FALSE
    B) if ALL of the options are TRUE
    C) if ii and iii are true
    D) if iii and iv are true
    E) if iii, iv, and v are true

    i. the tendon of flexor carpi radialis runs directly through the flexor retinaculum
    ii. only one nerve passes through the carpal tunnel
    iii. all of the long digital flexor tendons run through the carpal tunnel.
    iv. the radial and ulnar arteries do not run through the carpal tunnel
    v. the tubercles of the scaphoid and the trapezium form the lateral border of the carpal arch.
    B
  8. True or false (if false, provide the correct information): the flexor digiti minimi muscle inserts into the lateral margin of the extensor hood of the 5th digit.
    FALSE. The abductor digiti minimi muscle inserts into the medial margin of the extensor hood of the 5th digit.
  9. True or false (if false, provide the correct information): the superficial palmar arch is fed by a branch of the radial artery.
    TRUE
  10. True or false (if false, provide the correct information): the superficial branch of the ulnar nerve supplies one hypothenar muscle and sends back sensory information from the 3rd-5th digits
    FALSE. It supplies palmaris brevis, which is not a hypothenar muscle and sends back sensory information from the 5th and medial half of the 4th digit.
  11. A patient presents with compromised sensation on the dorsal medial palm. Which nerve is implicated?
    The dorsal branch of ulnar nerve
  12. Describe the innervation of the manual lumbricals, providing the nerve, spinal levels and primaries.
    1st and 2nd lumbircals are innervated by the 1st and 2nd digital branches of the median nerve. The 3rd and 4th lumbircals are innervated by the deep branch of the ulnar nerve. Both carry fibers from C8, T1. There are no primaries.
  13. List all of the muscles inserting into or arising from anywhere along the 3rd digit (extensor hoods, metacarpals and/or phalanges). BE SPECIFIC with muscle heads if necessary.
    • Extensor carpi radialis brevis
    • flexor carpi radialis
    • 2nd lumbircal
    • 2nd and 3rd dorsal interossei
    • flexor digitorum superficialis
    • flexor digitorum profundus
    • extensor digitorum
    • both heads of adductor pollicis
  14. If your C8 and T1 were completely non-functional, would you still be able to extend your thumb? If yes, explain why.
    Yes, through the abductor pollicis longus, extensor pollicis longus and extensor pollicis brevis muscles, which all receive spinal fibers from C7 as well as C8.
  15. If the lateral root of your median nerve was cut, would you still be would you still be able to oppose your thumb? Explain your answer, either way.
    Yes because the lateral root of the median nerve carries fibers from C5, C6 & C7. But the muscles that oppose the thumb carry fibers C7 AND C8 or from C8 and T1. So you'd be just fine...in this respect.
  16. If the fibers from the medial cord going to ulnar were non-functional, would you still be able to oppose your thumb to the distal phalanges of digits 2-5? Explain your answer in detail.
    • Hmmmm...yes for digits 2 and 3 but you'd look a bit odd and no for digits 4 and 5. You'd lose C8 and T1 from ulnar (though not from median), meaning you've lost adductor pollicis so your ability to adduct at the thumb at the MCP joint would be gone. You could still:
    • -flex and medially rotate the thumb MCP and IP joints through FPL and flexor pollicis brevis (anterior interosseous and recurrent branch of median, respectively)
    • -abduct the thumb at the CMC joint through abductor pollicis longus (posterior interosseous)
    • -flex digits 2&3 at the MCP and IP joints through flexor digitorum profundus and superficialis (anterior interosseous and median, respectively)
    • So for digits 2 and 3, opposition remains possible but it would look odd b/c you can' adduct the thumb (meaning that you'd have to really flex your digits).

    However, since the IP joints of digits 4 and 5 are flexed by FDP (innervated by C8 and T1 from ulnar), it is unlikely that the thumb would be able to reach the distal phalanges of digits 4 and 5.
  17. If your ulnar artery was completely blocked as it passed through the carpal tunnel would you lose your primary blood supply to opponens digiti minimi? Explain your answer.
    No because the ulnar artery does not pass through the carpal tunnel.
  18. If your ulnar artery was completely blocked as it passed into the wrist, would you lose your primary blood supply to opponens digiti minimi? Explain your answer.
    No for various reasons. First, primary is from branches of the deep palmar arch, which is the continuation of the radial artery. Also, the arches create continuous blood flow between radial and ulnar in the deep and superficial palm, so blockage in any one artery will not result in full blood loss.
  19. Which structures function to decrease pressure acting at the MCP joints and why?
    The medial and collateral ligaments at the IP joints, the palmar ligaments and the extensor hoods. They increase the articular surface area along the MC and phalangeal joint surfaces. Since pressure is inversely related to surface area, the additional surface area provided by these will decrease pressures acting at these joints.
  20. What is the common function of the flexor sheaths and the extensor retinaculum?
    They both prevent bowing of tendons (flexor sheaths of the long flexor tendons, extensor retinaculum of the extensor tendons of the posterior forearm)
  21. What function is enabled through the extensor hoods?
    The simultaneous flexion at the MCP joint and extension at the IP joints.

What would you like to do?

Home > Flashcards > Print Preview