1.4.2 Hand Flashcards
A continuation from the antebrachial fascia and the fascia of the dorsal hand, thin on thenar and hypothenar regions, thick in the center to form the ____.
Palmar aponeurosis
What is blended by the palmar aponeurosis? (Hint: a tendon and ligament)
Palmar carpal ligament and the palmar longus tendon
What are the two different orientations of the fibrous digital sheath?
Annular (ring-like) and cruciform parts
Lies deep to the palmar aponeurosis and palmaris longus tendon. It is also part of the palmar fascia.
Flexor Retinaculum
What forms the “roof” of the “Carpal tunnel”?
Flexor retinaculum
Where are the carpal tunnel and Guyon’s canal in relation to one another?
What side of the hand is typically affected by Dupuytren’s Contracture?
Medial side - 4th and 5th fingers
What is the classic population to get Dupuytren’s contracture?
Bilateral, male, over 50
What is Dupuytren’s contracture?
Progressive shortening, thickening, and fibrosis of the palmar fascia and aponeurosis.
What is the treatment for dupuytren’s?
Collagenase injections; surgical if injections don’t reduce enough of the fibrosis
What seperates the hypothenar compartment from the potential midpalmar space?
Medial fibrous septum
What seperates the thenar compartment from the potential thenar space?
lateral fibrous septum
What are the five compartments of the hand and their location?
Thenar, Hypothenar, Central, Adductor, Interosseus
What are the five compartments of the hand that house the intrinsic muscles?
Thenar, hypothenar, central, interosseus, and adductor
Which muscle in the hand is not within any of the compartments of the hand?
Palmaris brevis; runs superficially above the hypothenar
What helps form the thenar eminence and chief function is to oppose the thumb?
Thenar muscles?
What are the three thenar muscles?
Abductor policis brevis, flexor policis brevis, and opponens policis
Which thenar muscle is responsible for a little abduction of the thumb and assisting in the early stages of opposition?
Abductor policis brevis
What innervates the majority of the thenar muscles? What is the exception?
Median nerve;
the deep head of the flexor policis brevis is innervated by the ulnar nerve
Name the thenar muscles from superficial to deep?
Abductor pollicis brevis, flexor pollicis brevis, opponens pollicis
Identify these origins and insertions
What are the three hypothenar muscles?
abductor digiti minimi, flexor digiti minimi brevis, opponens digiti minimi
Which hypothenar muscle is the most superficial and ulnar (medial)?
abductor digiti minimi
What is the function of the abductor digiti minimi?
Abduction of the 5th digit
Which muscle lies lateral to the abductor digiti minimi? Its function?
The flexor digiti minimi; Flexes the 5th digit
Which hypothenar muscle lies the deepest? It’s function?
Opponens digiti minimi; allows for opposition of the 5th digit
Which group of muscles is responsible for the “L” or “Z” movement?
Lumbricals
Describe the innervation of the lumbricals?
1 & 2nd: Median nerve
3 & 4: Ulnar Nerve
What are the origins and insertions of the lumbricals?
Originate from the tendon of the flexor digitorum profundus tendon
Insert on lateral sides of extensor expansion
What is the two 1 1/2s and two 3 1/2s rule?
If the ulnar nerve is injured, how would the “z” move look? (hint: lumbricals)
The claw hand
(The lumbricals are dual innervated - with the 4th and 5th digits being innervated by the ulnar nerve)
Name this muscle
Adductor Pollicis
What innervates adductor pollicis?
Ulnar nerve
What function is mediated by the dorsal interossei?
Abduct the digits
Dorsal ABducts (DAB)
What innervates the dorsal interossei?
All are innervated by the ulnar nerve
What function is mediated by the palmar interossei?
Adducts the digits
Palmar ADduct (PAD)
Give a summary of all the intrinsic muscles of the hand and their compartment.
The tendons of these two extrinsic hand muscles are enclosed in a common flexor synovial sheath?
FDS and FDP
Compare the insertions of the flexors vs. extensors.
What type of injury could lead to tenosynovitis?
Puncture wound (ie. rusty nail)
Name this condition.
Tenosynovitis: infection of the synovial sheaths
Name this condition.
De Quervain’s Tenovaginitis Stenosans
(covered word is stenosis)
Name this condition.
Digital Tenovaginitis Stenosans (Trigger finger or snapping finger)
Where does the ulnar nerve enter the hand?
Guyon’s (Ulnar) canal
Name this branch of the ulnar artery?
Superficial palmar arch
Name this branch of the radial artery (anastamose with ulnar).
Deep palmar arch
What artery crosses the anatomical snuff box?
The radial artery
Why might profuse bleeding occur when one of the palmar arterial arches is lacerated?
Extensive anastomoses
What are the nine tendons that run through the carpal tunnel?
Four FDS, Four FDP, and one flexor pollicis longus
Name this nerve.
Median nerve at hand
Which branch of the median nerve innervates the thenar muscles?
Recurrent branch of the median nerve
This branch of the median nerve enters the hand superficially to the carpal tunnel?
Palmar branch of the median nerve
What is the treatment for carpal tunnel?
Trauma to the median can cause what appearance in the hand?
Ape hand (loss of ability to abduct and oppose thumb)
What provides innervation to the 5th digit and 1/2 of the 4th?
Superficial branch of the ulnar nerve
Name this nerve
Palmar cutaneous branch
Name this nerve.
Deep branch of ulnar nerve
Name the two 3 1/2s and 1 1/2s for the median and ulnar nerve
Name the four locations of ulnar nerve injury? Possible causes? Appearance?
What does the radial nerve innervate in the hand?
Name the muscles involved in each of these movements? Are these muscles intrinsic or extrinsic? What is their innervation?
