Wrist & Hand: Trigger Finger Flashcards
what is trigger finger?
stenosing flexor tenosynovitis
a condition in which the finger or thumb click or lock when in flexion - preventing return to extension
can affect 1 or more tendon(s)
what is the cause of trigger finger?
often occurs spontaneously in otherwise healthy individuals
what the prevalence of trigger finger?
2 in 100 people
what conditions is trigger finger associated with?
RA
amyloidosis
diabetes mellitus
what often precedes trigger finger?
flexor tenosynovitis - often from repetitive movements leading to inflammation of the tendon and sheath
what develops on the superficial and deep tendons with local tenosynovitis at the metacarpal head?
localised nodal formation on the tendon distal to the pulley
which pulley is most frequently involved ligament in trigger finger?
the A1 pulley
explain how the digit becomes locked in place
when the fingers are flexed the node moves proximal to the pulley. when the patient attempts to extend the digit this node fails to pass back under the pulley = locked in flexion
risk factors for trigger finger
- occupation/hobby that involves prolonged gripping and use of the hand
- RA
- DM
- female
- increasing age
clinical features
painless clicking (snapping or catching) when trying to extend the finger (most common middle and ring) more that 1 finger can be involved at a time and it may be bilateral over time - painful - on volar aspect of the MCP joint
what part of the phalanx should be palpated on examination of suspected trigger finger?
proximal aspect of phalanx - palpated to asses for clicking, pain with movement and any lumps of masses
DDx for trigger finger
Dupuytren’s contractrure - flexion is painless, fixed and cannot be passively corrected
infection - preceded with trauma, finger swollen, erythematous, tender, passive movement of digit causes pain
ganglion - involving tendon sheath
acromegaly - excessive growth results in swelling of flexor synovium within tendon sheath due to increased extracellular volume, limiting both flexion and extension in the affected digit
how is trigger finger diagnosed?
diagnosis is clinical
blood tests or imaging may be warranted to exclude any differentials
how is trigger finger managed?
mild - conservatively
splint to keep finger extended at night
steroid injections can be trialled for those who didn’t respond to conservative management
surgical management of trigger finger
a percutaneous trigger finger release via a needle can be attempted in most cases involving the release of the tunnel using a needle performed under local anaesthetic
for severe cases - surgical decompression of tendon tunnel can be trialled - where roof of tunnel is slit in turn widening its mouth to release the tendon - LA or GA
