Hand Flashcards
flexor tendon blood supply in relation to the MCP
proximal to the MCP nutrition is via diffusion from the synovial sheath
function of the triangular ligament
prevent volar subluxation of the lateral bands
function of the oblique retinacular ligament
link PIP and DIP extension
relationship of cleland and graysons ligaments to the neurovascular bundle
cleland is dorsal, graysons is palmar/volar. Graysons ground, Clelands ceiling
orientation of the flexors in the carpal tunnel
FPL is most radial. FDP all more deep than FDS. Long and ring FDS are most volar
orientation of the lumbrical insertions
volar to the transverse metacarpal ligaments, inserting on the radial side of the extensor hood/lateral bands
orientation of the digital nerves in relation to the arteries
nerves are volar to the arteries
AAOS postreduction guidelines for distal radius
stepoff
treatment of EPL rupture in distal radial fx care
common after closed treatment, and primary repair often not possible. Either palmaris graft, or EIP-to-EPL transfer
this is the most common tendon injury after volar plating of DR fx
FPL rupture.
vit C dose for RSD in DR fx
500mg per day
these scaphoid fxs are more at risk of AVN
waist and proximal pole
most common mechanism of scaphoid fx
forced hyperextension and radial deviation
indications for scaphoid fxs
displacement >1mm, humpback deformity (35* angulation), and trans-scaphoid perilunate dislocation
benefits of percutaneous fixation of scaphoid fx
faster time to union, and faster return to activity
benefits of volar approach to fixing displaced scaphoid fxs
avoids disruption to the blood supply, which is the dorsal branch off the radial artery that enters just distal to the waist
SNAC wrist stages
1 - radioscaphoid, 2 - + scaphocapititate, 3 - + lunocapitate
symptomatic hook of hamate fxs that fail nonop
excise; ORIF has high complication and little benefit
relative strengths of the carpal ligament fibers
the dorsal ones are stronger than the volar
etiology of DISI
SLL distruption
3 radiographic indications of DISI
SL angle >70*, SL interval >3mm, cortical ring sign
gold standard for dx of DISI
wrist arthroscopy
this is spared in SLAC wrist
radiolunate articulation
SLAC stages
radial styloid beaking, radioscaphoid, midcarpal
in chronic SL instability this is a treatment option
ECU tendon graft
2mm of metacarpal shortening equals this amount of extensor lag
7*
deforming force in baby bennett
ECU
deforming force in bennett
APL and the thumb extensors, cause proximal, dorsal, and radial displacement of the metacarpal shaft. Adductor pollicis causes supination and adduction.
anterior oblique ligament (beak) in bennett fxs
connection between the volar-ulnar portion of MC shaft and the trapezium
why thumb MCP stability is tested in 0* and 30*
instability at 30* is due to UCL proper. Instability at both 0* and 30* implies injury to the volar plate and/or accessory UCL
stener lesion
interposition of the adductor pollicis aponeurosis between the avulsed UCL and its insertion on the proximal phalanx
PIP dorsal disloc’n
Injury to volar plate AND at least one collateral.
PIP volar disloc’n
Injury to central slip AND at least one collateral.
result of poorly treated PIP volar disloc’n
since these are central slip injuries, they can go on to boutonniere deformity
rotatory PIP dislocations hard to reduce bc
phalangeal condyle buttonholes through lateral bands and the central slip
initial mgmt of chronic injury resulting from central slip rupture
boutonniere deformity, needs to have maximal passive motion prior to any operative treatment. Dynamic splinting or serial casting
strength of flexor tendon repair proportional to
number of strands that cross repair
benefit of high-caliber suture in flexor tendon lacs
decreases gap formation, increases strength and stiffness
benefit of locking loop technique in flexor tendon lacs
decreases gap formation
why repair the epitenon in flexor lacs
increases repair strength by 30-50%
repair of the flexor tendon sheath in lac repair
no benefit
timeframe for weakness in tendon repair
3 weeks is weakest, and fails at the knots
minimum repair of flexor tendon lac to allow active motion protocol
4 strand repair needed for active motion
types and the mgmt of zone I flexor tendon injuries
type I retracts all the way to the palm and needs to fixed within 7-10 days. type 2 can wait 6 weeks, as the vinculae prevent retraction past PIP. Type 3 also can wait 6 weeks.
how quadrigia occurs
if an injured 3-4-5 FDP is advanced more than 1cm, the remaining 3-4-5 digits will not flex anymore once the repaired digit bottoms out.
commonality b/t kleinert and duran OT protocols
both restrict active flexion for 6 weeks
how flexion is performed with the kleinert and duran protocols
in the kleinert passive flexion performed with bands (?) and duran it is performed with the other hand (COMPLIANCE)
difference bt pediatric and adult trigger thumbs
in peds the pathology is in the tendon itself, rather than the tendon sheath
treatment for pediatric trigger finger
a simple A1 pulley release may not be enough. May need to release A3, or resect FDS slip
this % gets better with injection of DQ synovitis
80%
this tendon often has more than one slip when surgically treating 1st dorsal compt synovitis
APL
this tendon often has its own compartment when surgically treating 1st dorsal compt synovitis
EPB
intersection syndrome
inflammation/bursitis bt the 1st and 2nd dorsal extensor compartments
this motion can lead to traumatic subluxation of the ECU tendon
hypersupination and ulnar deviation
rate of incidental TFCC tears in wrist scopes
50%
ulnar variance with pronation
positive
ulnar variance with supination
negative
these two ligaments have their origins on the TFCC
ulnolunate and ulnotriquetral ligaments
percent of load borne by the TFCC at neutral ulnar variance
20%
surgical considerations in ulnocarpal impaction syndrome
if the DRUJ is free of arthritis, you can shorten the ulna
threshold for removal of nail plate in subungal hematoma
> 50%
why are FTSG better for fingertip injuries
sensibility, durability
flap for volar oblique fingertip injury
cross-finger
flap for volar oblique fingertip injury to the index or middle digit
either cross-finger, or can do thenar flap
who would get a thenar flap, and what are the concerns
flap for volar oblique fingertip injury to the index or long, and can get PIP stiffness especially if older
flap for transverse or dorsal oblique fingertip injury
V-Y advancement
flap for transverse or volar oblique fingertip injury of the thumb
moberg
probably created a few of these in the mgmt of fingertip injuries treated by acute shortening
lumbrical plus finger can result from violation of the FDP insertion and retraction. This pulls on the lateral bands (and the extensor mech) through the lumbricals, as they originate on the now shortened FDP
this flap is done for dorsal thumb skin loss
kite flap (1st dorsal metacarpal artery)
these are preferred for coverage of dorsal hand wounds
STSG
these are preferred for coverage of volar hand wounds and fingertips
FTSG
this provides 75% lengthening along the central limb of a flap
60* Z-plasty
blood supply for gracilis flap
medial femoral circumflex
blood supply for latissimus flap
thoracodorsal
blood supply for serratus flap
serratus branch of the subscapular artery
blood supply for anterolateral thigh flap
descending branch of the lateral femoral circumflex
blood supply for lateral arm flap
posterior branch of the radial collateral artery
amputations in zone II: replant?
nope
amputations in zone I: replant?
relative indication to replant distal to the FDS insertion
amputations at the wrist level: replant?
wrist level and proximal is indication to replant
amputations in polytrauma: replant?
along with psych conditions, polytrauma pts may be poor replant candidates
sequence for replant of a single digit amputation
bone, extensors, flexors, artery, vein, nerve
sequence for replant of multiple digit amputation
thumb, long, ring, small, index
what else can be measured besides pulse ox in replanted digit
skin surface temperature; 2* in an hour indicates decreased perfusion
most predictive of digit survival after replant
mechanism of injury, then probably ischemia time
failure of replant within 12 hours
arterial vasospasm
failure of replant after 12 hours
venous congestion
this goes with leech therapy for late replant failure
cipro or rocephin; leech saliva has aeromonas in it
most commonly performed procedure after successful replant
tenolysis
ring avulsion injuries
treatment depends on vascularity first, then bony or tendon injury. 1 - circulation intact, salvage with coverage. 2 - circulation disrupted, but no gross bony or tendon injury, revascularization. 3 - complete degloving, needs amp’d.
this class of meds may help with raynaud’s dz
calcium channel blockers
these muscles are the most vulnerable to ischemic forearm contracture
FDP and FDL
imaging in frostbite
bone scan
these are last to go in compression neuropathy
pain and temperature sensation
viral illness preceding neuritis
parsonage-turner
semmes weinstein test this
cutaneous pressure threshold; large nerve fibers (which are first to be affected in compressive neuropathy)
greater than this 2 point is abnormal sensation
6mm
most common cause of CTS in peds
mucopolysaccharidoses
injection rate of success in CTS
80% after 6 weeks, but only 20% of those are symptom-free at 1 year. Surgery is less successful for those in which injections don’t work
how to distinguish pronator syndrome from carpal tunnel syndrome on sensation alone
palmar cutaneous branch of the median nerve won’t be affected in CTS (comes off prior)
sites of pronator compression
ligament of struthers, lacertus fibrosis (biceps aponeurosis), two heads of pronator teres, FDS aponeurosis
testing for pronator syndrome
pain with resisted elbow flexion in forearm supination, and forearm pronation with elbow extended
pronator syndrome associated with this and improves if you treat it
medial epicondylitis
compressive neuropathy with pure motor loss
AIN syndrome. FPL, FDP to 1st, pronator quadratus
testing for pronator quadratus involvement in AIN syndrome
pain on resisted pronation with elbow flexed
AIN syndrome could be confused for this
Mannerfelt lesion in RA. This is FPL rupture.
floor of the cubital tunnel
MCL and elbow capsule
wartenberg sign
pinky abduction and extension when trying to adduct; ulnar nerve compression
threshold for diagnosis of ulnar compression based on conduction velocity
conduction velocity less than 50m/sec
ulnar decompression vs transposition
no difference
most common cause of ulnar tunnel syndrome
ganglion cyst
PIN syndrome exam
radial deviation with wrist extension (ECRL innervated higher)
sites of PIN compression
CHEFS - capsule, leash of Henry, ECRB, arcade of Frohse, supinator (distal edge)
most important prognostic factor for nerve recovery after injury
age
indication for nerve conduit in digital nerve
gap larger than 8mm
this type of plexus injury has the worst prognosis
preganglionic
most important predictor of success in operative mgmt of CP
voluntary muscle control
this has not demonstrated a benefit over placebo or corticosteroids in CMC arthritis
off-label hyaluronic acid
there is evidence that this has similar outcome to more complicated basal joint arthritis treatments
trapeziectomy
first to be affected in vaughn-jackson syndrome
EDM
direction of progression in vaughn-jackson
from the EDM radially
mannerfelt lesion
attritional FPL rupture, due to volar STT joint osteophyte
treatment of mannerfelt lesion
direct repair fails, so tendon transfer more desirable
this might be the initial presentation of RA MCP joint involvement
extensor lag
why RA MCP’s deviate ulnarly
pannus stretches the weaker radial sagittal bands
this is a temporary solution in RA MCP treatment
synovectomy and centralization of the extensor tendons
perilunate dislocation begins with
scaphoid extension, then scaphoid failure
mayfield progression
scaphoid extension, scaphoid failure, distal row dissociation, triquetral hyperextension, lunotriquetral ligament failure, dorsal dislocation of the carpus
