Hand Flashcards
SNAC Stage I
Arthrosis between scaphoid and radial styloid – treat with radial styloidectomy
SNAC Stage II
Arthrosis between scaphoid and capitate – treat w/ PRC, 4 corner fusion or wrist arthrodesis
SNAC Stage III
Periscaphoid arthrosis — treat with PRC, 4 corner fusion or wrist arthrodesis
Which joint is usually not involved in a SNAC wrist?
radiolunate
Chronic nonunion fx of hook of hamate can cause…
rupture of small finger FDP and ulnar neuropathy.
Pisiform is located within…
FCU tendon
Treatment of pisiform fracture
Acute: immobilize
Chronic: excision of fracture fragment
(same as hook of hamate fx)
Treatment of metacarpal fx shaft
CRPP or ORIF if it is intra-articular, rotationally malaligned or multiple MCs
For an oblique MC shaft fx, preferred treatment is…
interfragmentary fixation over plate
Bennett fracture
intra-articular fracture of the volar lip of the thumb MC base
(the volar oblique ligament holds the fragment in place)
Rolando fracture
comminuted intra-articular fracture of the thumb MC base
A thumb CMC dislocation is usually…
dorsal due to disruption of the dorsoradial ligament.
What can prevent reduction in a dorsal PIP dislocation?
volar plate
Disruption of the volar plate in a PIP dislocation can lead to….
swan neck deformity
The most common fracture from a dorsal PIP dislocation is…
volar lip of P2.
If less than 40% of joint involved or stable joint after reduction, treat with dorsal extension block splint w/ active flex/ext.
If more than 40% or joint is unstable, CRPP vs ORIF.
A volar PIP dislocation can lead to…
central sip disruption and ultimately boutonniere deformity.
In a volar PIP fracture dislocation, if less than 40% of the joint is involved, then treat with…
extension splinting.
Treatment of a comminuted volar base middle phalanx fracture in a young patient
hemi-hamate arthroplasty
Treatment of acute tendon rupture
4-strand core repair (placed 1 cm away from edge) with 6-0 epitendinous suture (DONT lock)
Treatment of chronic tendon rupture
silastic tendon implant with staged reconstruction
Treatment of partial tendon rupture (<60%)
early ROM
BUT if there is triggering, trim the frayed edges (do NOT perform tenorrhaphy)
If there is a FDS rupture in Zone II…
repairing only 1 slip improves gliding
Which pulleys are most important to prevent bowstringing?
A2 and A4
What happens if you release the oblique pulley of the thumb?
bowstringing of FPL
Jersey finger
FDP avulsion leading to DIP extension at rest
Treatment of Jersey finger
direct repair if acute, 2 stage reconstruction if chronic
Quadrigia effect
results if FDP is functionally shortened > 1 cm
FDP to long, ring and small fingers share a common muscle belly –> shortening of one FDP tendon leads to flexion lag to the other two tendons
The lumbricals originate from…
FDP and insert on the radial lateral bands.
Lumbrical innervation/muscle bellys
Lumbricals 1&2: unipennate, median nerve innervated
Lumbricals 3&4: bipennate, ulnar nerve innervated
When FDP is functionally impaired, firing of FDP causes…
pull on the lumbricals ultimately leading to paradoxical finger extension (aka lumbrical plus).
Mallet finger
disruption of terminal extensor tendon leading to DIP flexion at rest
Mallet finger should be treated operatively when…
there is a large bony mallet or with subluxation of the distal phalanx.
Mallet finger can ultimately lead to…
swan neck deformity.
Swan neck deformity is most often caused by…
volar plate injury/attenuation which leads to PIP hyperextension and DIP flexion.
Boutonniere deformity is due to…
central slip disruption. Normally, the central slip helps EDC extend the PIP.
Disruption of the central slip causes…
volar migration of the lateral bands which leads to PIP flexion and DIP extension due to unopposed pull of the lumbricals.
Elson test
with the PIP flexed to 90, attempted extension of the PIP leads to DIP hyperextension.
Due to central slip disruption.
Acute central slip injury treatment
extension splinting or repair
Chronic central slip injury treatment
lateral band relocation
In a perilunate dislocation, if the lunate dislocates volarly into the carpal tunnel, then need to…
perform combined dorsal and volar approaches.
Which ligament is normally intact in a perilunate dislocation?
short radiolunate
Treatment of chronic perilunate dislocation
PRC
Scapholunate ligament deficiency leads to…
dorsal intercalated segmental instability (DISI)
DISI
Lunate is tilted dorsally (extended).
Acute: SL repair
Chronic: SL reconstruction
Terry Thomas sign
scapholunate diastasis > 3 mm with clenched fist xray (sign of DISI)
Lunotriquetral ligament deficiency leads to…
volar intercalated segmental instability (VISI).
The lunate is tilted volarly (flexed).
SLAC Stage I
arthritis between scaphoid and radial styloid
Treatment: styloidectomy and scaphoid stabilization, PIN/AIN neurectomy
SLAC Stage II
arthritis between scaphoid and entire radius
Treatment: PRC, scaphoid excision, 4 corner fusion
SLAC stage III
arthritis between capitate and lunate
Treatment: scaphoid excision & 4 corner fusion or radiocarpal arthrodesis
Which joint is not involved in a SLAC wrist?
radiolunate joint
Which ligament needs to be preserved during PRC?
RSC (in order to prevent ulnar subluxation of the carpus)
Gamekeeper’s thumb (or skier’s)
UCL injury
Stener lesion
avulsed UCL is displaced above the adductor aponeurosis (which then blocks reduction of the UCL
Proper UCL tear vs Accessory UCL tear
Valgus instability when the thumb MCPJ is at 30 degrees of flexion indicates proper tear.
Valgus instability when the thumb MCPJ is at full extension indicates accessory UCL tear.
Sagittal band rupture leads to…
dislocation of the extensor tendon especially during MCP flexion with the wrist flexed.
Which sagittal band ruptures more often?
The radial sagittal band leading to tendon dislocation ulnarly.
Tx of acute sagittal band rupture
extension splinting of MCPJ
Tx of chronic sagittal band rupture (or in an athlete)
direct repair if possible, otherwise extensor centralization procedure
In a rheumatoid hand, sagittal band dysfunction leads to…
ulnar deviation of the digits.
Claw hand (intrinsic minus) is…
MCP hyperextension (strong EDC) and PIP/DIP flexion (strong FDS/FDP) and is due to ulnar or median nerve palsy (Volkmann’s ischemic contracture).
Extrinsic tightness
more PIP flexion with MCP extension than with MCP flexion due to extensor tendon adhesions.
Intrinsic plus hand is…
weak extrinsics and spastic intrinsics leading to MCP flexion and PIP/DIP extension.
Intrinsic tightness
Less PIP flexion with MCP extended than with MCP flexed
Treat with therapy/distal intrinsic releases
Gold standard for dx of hypothenar hammer syndrome
arteriography
Treatment of ulnar artery thrombosis
observation
tx of ulnar artery aneurysm (corkscrew artery)
excision and reconstruction
Raynaud’s disease vs syndrome
dz: idiopathic
syndrome/phenomenon: known cause
Non-op tx of Raynauds
Botox injection decreases pain and improves perfusion via inhibition of presynaptic release of acetylcholine
Sx tx of Raynauds
periarterial sympathectomy and possible microvascular reconstruction
Buerger’s disease (thromboangiitis obliterans)
vasculitis in smokers leading to digital ischemia and ulceration due to thrombosis.
Smoking cessation can reverse dx and prevent amputation.
Dupuytren’s disease
contractures due to myofibroblast activity
DIP contracture: retrovascular cord
PIP contracture: spiral cord
MCP contracture: central cord
Web space contracture: natatory cord
Which cord is most important in Dupuytren’s?
spiral cord (PIP)
Which direction is the NV bundle displaced in Dupuytren’s?
centrally and superficially
Which ligament is NOT involved in Dupuytren’s?
Cleland’s ligament
Treatment of ulnocarpal abutment (positive ulnar variance) if fails non-op
No arthritis: ulnar shortening osteotomy
Low-demand patient w/ arthritis: Darrach
High-demand patient w/ arthritis: Sauve-Kapandji or ulnar hemiresection arthroplasty w/ TFCC repair/reconstruction
Basilar thumb arthritis shows…
1st web space adduction contracture, MCP hyperextension
Treatment of basilar thumb arthritis
trapeziectomy with ligament reconstruction and tendon interposition w/ FCR
(if FCR is compromised, can use ECRL or APL)
If there is CMC and STT arthritis, when you perform LRTI, you also have to…
address the STT arthritis by excising the proximal trapezoid
Heberden’s node
DIP arthritis
Bouchard’s node
PIP arthritis
Psoriatic arthritis findings
- pencil in cup deformity
- nail pitting (onychodystrophy)
- skin plaques
- dactylitis (diffuse digital swelling)
Brachial plexus injury can be either…
pre-ganglionic (proximal to DRG) injury or post-ganglionic (distal to DRG).
Examples of pre-ganglionic injury
- Horner’s syndrome (sympathetic chain)
- medial scapular winging (long thoracic nerve)
- elevated hemidiaphragm (phrenic nerve)
- paralysis of rhomboids (dorsal scapular nerve)
- cervical paraspinals
Histamine testing of different brachial plexus injuries
Pre-ganglionic: normal histamine (bc of preserved sensory nerve action potentials)
Post-ganglionic: abnormal histamine test
Gold standard for diagnosing nerve root injury
CT myelogram
Post-ganglionic brachial plexus injuries have a better prognosis because…
of nerve regeneration (1 mm/day) via wallerian degeneration of the distal segment (phagocytosis by macrophages) and antegrade regeneration of the proximal segment.
Best predictor of nerve regeneration
tinel sign
Oberlin trasnfer
transfer fascicles of the ulnar nerve to the motor nerve of the biceps
Double nerve transfer
transfer (1) fascicles of ulnar nerve to the motor nerve of the biceps and (2) fascicles of the median nerve to the motor nerve of brachialis
AIN compression demonstrates…
no pain or sensory deficits (motor only)
Motor deficits: FPL, FDP of index and long fingers, pronator quadratus
Compression sits of AIN
ulnar head of pronator teres, FDS arcade
Pronator syndrome compression sites
- supracondylar process
- ligament of struthers
- bicipital aponeurosis/lacertus fibrosus
- FDS aponeurotic arch
- between ulnar and humeral heads of pronator teres
What differentiates pronator syndrome from carpal tunnel?
palmar cutaneous branch of the median nerve is affected in pronator syndrome
Within the carpal tunnel, tendon location…
FDS of long and ring fingers are volar to FDS of index and small fingers
Injury to the recurrent motor branch of the median nerve during carpal tunnel release leads to…
APB weakness
When does grip strength return to pre-op strength after carpal tunnel release?
12 weeks
Tx of CTS w/ significant thenar wasting
transfer EIP around ulnar wrist (opponensplasty) to improve opposition function
Froment sign
thumb IP flexion (FPL) compensates for weak adductor pollicis during pinch
Wartenberg sign is due to..
weak intrinsics (specifically palmar interosseous muscle to the LF) and unopposed pull of EDM
First dorsal web space atrophy is due to…
dorsal interossei atrophy
Ulnar tunnel syndrome has similar symptomatology as cubital tunnel syndrome except…
there is no sensory deficit to the dorsum of the hand (dorsal cutaneous branch of ulnar nerve spared) and no FCU/FDP weakness
Radial tunnel syndrome
PIN compression w/ pain but no sensorimotor deficits
- pain with resisted long finger extension and forearm supination
- pain 3-4 cm distal to lateral epicondyle over the mobile wad
***if there are sensorimotor deficits, then it is called PIN compression syndrome.
Sites of radial nerve compression
- arcade of Frohse
- leash of Henry
- ECRB
- fibrous bands anterior to radiocapitellar joint
Wartenberg’s syndrome
compression of superficial sensory radial nerve between BR and ERCL w/ forearm pronation
Radioulnar synostosis is a failure of…
segmentation (typically occurs from distal to proximal).
In radioulnar synostosis, the forearm is often fixed in…
pronation. The shoulder abducts to compensate for this.
When to consider surgery for radioulnar synostosis
- if there is functional impairment or bilateral involvement
- treat with excision and vascularized fat interposition or forearm derotational osteotomy
Characteristics of congenital radial head dislocation (compared to traumatic)
- radial head is convex
- capitellum is hypoplastic
- bilateral involvement common
- radial head usually dislocated posteriorly
Treatment of congenital radial head dislocation
- usually painless however symptoms can be present at wrist due to ulnar impaction
- if symptomatic, tx w/ radial head resection after skeletal maturity
Madeung’s deformity
dyschondrosis of volar and ulnar aspects of distal radial physis leading to increased volar tilt and radial inclination
Leri-Weill dyschondrosteosis
SHOX mutation
bilateral madelung’s deformity
Radial clubhand is due to…
defect of apical ectodermal ridge (AER).
If radial clubhand is due to thrombocytopenia absent radius (TAR), will find…
thumb is present.
If radial clubhand is due to Holt Oram, look for…
cardial anomaly.
If radial clubhand is due to Fanconi anemia, look for…
aplastic pancytopenia and chromosomal breakage test.
Workup of longitudinal radial deficiency includes…
- renal US
- echo
- CBC
Treatment of radial clubhand
If there is active elbow flexion: ulnar centralization and tendon transfers at 6-12 months of age
With thumb hypoplasia, CMC stability determines…
thumb reconstruction w/ opponensplasty (stable CMC) vs ablation and pollicization (unstable CMC)
Preaxial polydactyly is typically seen in…
caucasians (double thumb). Resect the smaller thumb (usually radial).
**preserve intrinsic tendon and collateral ligament insertions
Postaxial polydactyly is typically seen in…
African Americans. (extra digit next to SF)
***If you see this in caucasian, needs genetic workup.
Camptodactyly
PIP flexion of SF –> tx w/ progressive stretching and splinting
(can be associated with camptodactyly-arthropathy-coxa vara-pericarditis)
Syndactyly is due to…
failure of apoptosis of digital web space.
Poland syndrome
- unilateral chest wall hypoplasia (pec major)
- unilateral hypoplasia of UE
- symbrachydactyly (absent/short middle phalanges)
- associated w/ subclavian artery hypoplasia
Apert syndrome
- FGFR2 mutation
- complex syndactyly
- craniofacial synostosis
- symphalangism (fused IP joints)
Syndactyly release can be performed at…
1 year of age.
Web creep is most common complication.
Epiphysiodesis is performed for macrodactyly when…
the involved digit reaches normal adult length
Tx of amniotic band syndrome (aka Streeter’s dysplasia)
excise constriction band and perform Z-plasty
Keinbock’s disease
avn of lunate
Keinbock’s risk factors
-negative ulnar variance cuasing increased contract stress between lunate and radius
Tx of pediatric Keinbock’s
temporary STT pinning
Tx of adult Keinbock’s w/ no or minimal collapse
Negative ulnar variance: radial shortening osteotomy
Normal ulnar variance: DR core decompression
Tx of adult Keinbock’s w/ collapse
PRC, arthrodesis or total wrist arthroplasty
Indications for digital replant
- multiple digits
- amputation distal to FDS insertion
- thumb amputation
- pediatric patient
Contraindications for digital replant
- ribbons sign
- warm ischemia time > 12 hours
- cold ischemia time > 24 hours
Order of structures for replantation
Bones Extensors Flexors Arteries Nerves Veins
Treatment of arterial thrombosis w/i first 12 hours of replant
remove bandage, place hand in dependent position, heparin, stellate ganglion block
Treatment of venous thrombosis after replant (after 1st 12 hours)
elevate hand, leech therapy (risk for aeromonas infxn so prophylax w/ Bactrim or Cipro)
Reperfusion injury is proposed to be due to…
allopurinol inhibits xanthine oxidase which leads to decreased xanthine
Fingertip injury
Adult w/ no exposed bone: soft dressing
Kid w/ exposed bone: soft dressing
VY advancement flap indicated for…
transverse or dorsal oblique fingertip injury
Thenar flap indicated for…
volar fingertip injury (overlying P3) to index or long finger
(risk of PIP contracture)
Cross finger flap indicated for…
volar injury to digit (overlying P1/P2)
Reverse cross finger flap indicated for…
dorsal injury overlying P1/P2
Moberg volar advancement indicated for…
volar thumb injury < 2 cm
FDMA flap indicated for…
volar thumb injury > 2 cm or dorsal thumb injury
Z-plasty lengthening for contracture
45 degree limbs –> length increases by 50%
60 degree limbs –> length increases by 75%
After peripheral nerve injury, sympathetic activity is…
last to be lost and first to recover. Motor function is first to be lost and last to return.
What is the maximum gap that can be bridged by a nerve collagen conduit?
3 cm
Tx of hemorrhagic blister
drain blister but leave overlying skin intact
Treatment of pasteurella
gram negative coverage such as ampicillin/sulbactam