Hand Flashcards
(109 cards)
What type of collagen for Dupuytren’s contracture tissue?
Type 3 collagen***
Where do A1, A3 and A5 pulley originate from?
Palmar plate***
A2 and A4 arise from periosteum in proximal half of proximal phalanx and midportion of middle phalanx respectively ***
Overlie MP, PIP and DIP respectively
What pulley prevents bowstringing of FPL in thumb?
Oblique pulley*** (also have to have A1 pulley cut to get bowstringing)
Originates at proximal half of proximal phalanx
Which nerve is closest to A1 pulley in thumb?
Radial digital nerve (2.7 mm vs ulnar 5.4 mm)
Two most important pulleys to maintain in fingers?
A2 and A4 - prevent bowstringing
Sequence of pulleys from proximal to distal in fingers?
A1, A2, C1, A3, C2, A4, C3
What supplies superficial arch of hand?
Ulnar artery mainly, minor contribution from superficial branch of radial artery ***
Where are digital nerves vs digital nerves in palm and digits?
Palm: digital arteries are VOLAR to nerves
Digits: Arteries are DORSAL to digital nerves –> NV bundle is volar to Cleland’s ligament
Blood supply for superficial and deep palmar arches?
Superficial: ulnar, give off common digital arteries (main blood supply for digits on the median side of digit/closer to midline)
Deep: radial***
Disruption of SL ligament causes?
Disruption of LT causes?
DISI deformity*** (along with dorsal intercalated segment instability)
VISI deformity*** (along w/ radiotriquetral ligament)
Volar extrinsic ligaments while viewing form 3-4 portal (between EPL and EDC) order from radial to ulnar?
Radioscaphocapitate (most radial)***
Long radiolunate***
Short radiolunate***
Main restraint against ulnar translation of carpus?
Radioscaphocapitate ligament***
What is jersey finger?
FDP avulsion injury from insertin at base of distal phalanx***
Unable to flex DIP***
Generally fix (acutely if retracted to palm vs within weeks if less retracted)***
What is the closest tendon to the median nerve?
FCR***
How far away from flexor tendon injury should suture be placed?
10 mm***
When to consider 2 stage flexor tendon grating?
> 3 months since injury***
How long to cast a kid with flexor tendon injury?
3-4 weeks***
% of flexor tendon cut to repair?
> 60%***
What causes a swan neck deformity
Lax volar plate***
mallet finger - Lesa transfer of DIP extension force into PIP extension force***
FDS rupture - unopposed PIP extension combined with loss of integrity a volar plate
intrinsic contracture - tethering of lateral / collateral bands by transverse retinacular ligament as result of PIP hyperextension. If these are tethered, excursion is restricted in the extension forces not transmitted to terminal tendon and instead transmitted PIP joint
Where do lumbricals originate and insert?
Lumbrical plus?
Originate from FDP and insert onto radial side of extensor expansion***
with FDP laceration, FDP contraction leads to pull on lumbricals –> lumbricals Paula lateral bands leaned PIP and DIP extension of involved digit - can lead to “lumbrical plus” effect –> paradoxical extension of the IP joint when attempting to flex the fingers***
occurs with amputation at the level of the DIP**
Quadrigia?
FDP*** tendons of long, ring and small fingers share common muscle belly –> exucrusion of combined tendon = Shortest tendon
improper shortening of the tendon during repair results and inability to fully flex adjacent fingers***
Who is at risk of trigger finger?
DM patients*
Females >50 y/o*
hypothyroidism***
Caused by stenosing tenosynovitis of the A1 pulley***
What nerve at risk with trigger thumb release?
radial digital nerve***
Elson test?
flex patient PIP joint over a table at 90° in as an to extend against resistance
if central slip is intact, DIP will remain supple***
if central slip is disrupted, DIP will be rigid.***