Cortex- Upper limb: Hand Flashcards
What forms the carpal tunnel
carpal bones and flexor retinaculum
what passes through the carpal tunnel
median nerve and 9 flexor tendons (FDS & FDP to 4 digits + FPL) with their synovial covering
what results in synovial nerve compression
any swelling of the contents of the cubital fossa (felxor tendons and their syonvial coverings)
what can cause carpal tunnel syndrome
idiopathic (most cases)
secondary to- RA, fluid retention (pregnancy, diabetes, chronic renal failure, hypothyroidism), fractures (esp colles fracture)
what is myxoedema
swelling of the skin and underlying tissues giving a waxy consistency- seen in hypothyroidism
who gets carpal tunnel
women 8x more likely than men
how do patients with carpal tunnel present
parathesiae in the median nerve innervated digits (thumb and radial 2 1/2 digits) which is worse at night
loss of sensation
sometimes weakness of the thumb and clumbsiness in the areas of hand supplied by the median nerve
what is seen on examination of carpal tunnel syndrome
demonstrable loss of sensation and/ or muscle wasting of their thenar eminence (in chronic severe cases)
symptoms reproduced by doing tinels test (percussing over the median nerve) or phalens test (holding the wrists hyper-flexed which decreases space in carpal tunnel)
how can you confirm the diagnosis of carpal tunnel
nerve conduction studies- will show slowing of conduction across the wrist
what is the treatment for carpal tunnel syndrome
wrist splints at night to prevent flexion
injection of corticosteroid
surgery- carpal tunnel decompression (division of the transverse carpal ligament under local anaesthetic)
what is dupuytren’s contracture
proliferative connective tissue disorder
the specialised palmar fascia undergoes hyperplasia
normal fascial bands form nodules and cords
progresses to contractures at the MCP and PIP joints
describe the pathology of dupuytrens contracture
proliferation of myofibroblast cells and the production of abnormal collagen (type 3 rather than type 1)
describe the clinical signs of dupuytrens contracture
skin may be aderent to the disease fascia and puckered
palpable nodules may be present
contractures most commonly affect the ring and little fingers
50% have bilateral involvement
who gets dupuytrens contracture
men 10:1, high prevelance in northern european/ scandinavian descent
can be familial- autosomal dominant
what can dupuytrens occur secondary to
is a feature of alcoholic cirrhosis
side effect of phenytoin therapy
common in diabetics
fibromatoses- peyronies disease (affects penis) and plantar fibromatosis (ledderhose disease-affects the feet)
what is the treatment for dupuytrens contracture
mild ones can be tolerated
surgery if interfering with function - (fasciectomy- removal of all diseased tissue and fasciotomy- division of cords)
amputation if severe (finger in palm)
(30 degrees of contracture can be tolerated at the MCP joint but the PIPJ readily stiffens and any contracture here is an indication for surgery)
what is trigger finger
tendonitis of a flexor tendon to a digit
resulting in nodular enlargement of the affected tendon
usually distal to a fascial pulley over the metacarpal neck
(A1 pulley)
what causes the ‘trigger’ finger sign
movement of this finger produces a clicking sensation as this nodule catches on and then passes underneath the pulley
this might be painful
finger may lock in flexed position as the nodule cannot pass back under the pulley on extension
what fingers are most commonly affected in trigger finger
middle and ring
what is the treatment for trigger finger
injection of steroid around the tendon within the sheath will relieve symptoms
surgery offered in recurrent and persistent cases (incision of the pulley to allow the tendon to move freely- divison of A1 pulley doesn’t affect function)
what hand arthritis is common in post menopausal women
DIP OA
what is seen clinically in DIP OA
DIPs will become painful, swollen and tender- fill eventually affect all fingers
stiffness and bony thickening (heberdens nodes)
associated dorsal ganglion cyst (mucous cyst) may be present
how can OA be treated
mild to moderate- removal of osteophytes and excision of any mucous cysts
severe pain- arthrodesis
what are bouchards nodes
bony swelling of the PIPs in OA
what might be required to preserve pinch grip in PIP OA
index finger arthrodesis
what is a possible surgery option for OA in the fingers
arthroplasty (variable results, extensor tendon subluxation)
what can cause OA in the MCP joints
previous injury, occupational stress, gout or infection
is surgery possible for OA at MCPs
yes- arthroplastys may relieve pain and improve ROM but complications (ulnar drift, extensor tendon subluxation)
what is the trapziometacarpal joint
1st carpo-metacarpal joint (base of the thumb)
why is the trapziometacarpal joint significant
commonly affected by OA, particularly in women
what can treat trapziometacarpal joint OA
injection of steroid can help in an acute flare up
excision arthroplasty or fusion may cure chronic pain
when does OA of the radio-carpal joint of the wrist occur
as a consequence of trauma
why is RA in the hand so important
where it seems to cause the most problems and is most visible
what will patients with long standing RA (without treatment) develop
deformed, painful and occasionally malfunctioning hands
what joint does RA tend to spare
the DIPs
what are the three stages of RA in the hands
- synovitis and tenosynovitis- inflammation within the joints and the tendon sheath leading to swelling and pain in the affected structures
- erosions of the joints- inflammatory pannus denudes the joints of articular cartilage
- joint instability and tendon rupture- following progressive destruction of bony and soft tissue structure, patients can progress to subluxation. chronic tenosynovitis predisposes to extensor tendon ruptures.
name 5 deformities seen in end stage hand RA
volar MCPJ subluxation
ulnar deviation
swan neck deformity (hyperextension at PIPJ with flexion DIPJ)
boutonniere deformity (flexion at PIPJ with hyperextension at DIPJ
z shaped thumb
what surgery may prevent tendon rupture in RA
tenosynovectomy (excision of synovial tendon sheath)
is surgery to fix rupture of extensor tendons to the wrist or fingers possible
not directly as diseased tendon will fail
tendon transfers or joint fusion may be required to preserve function
what surgeries may be required in RA
soft tissue releases (lengthening) for contractures
MCP replacements, PIP replacements of fusions, wrist replacements or fusion may be required for severe arthritic change
what are ganglion cysts
common mucinous filled cysts found adjacent to a tendon or synovial joint
where are ganglion cysts common
DIPJ- mucous cyst, flexor tendon
wrist: dorsal or volar
foot, ankle, knee (bakers cyst)
what are the symptoms of a ganglion cyst
localised pain or irritation
cosmetic displeasure
what do ganglion cysts look/feel like
firm, smooth, rubbery, should transilluminate
what is the treatment for a ganglion cyst
surgery for cosmesis not on NHS
surgical excision required if the swelling causes localised discomfort
needle aspiration may be attempted (recurrence common)
what are the 2nd most common soft tissue swellings of the hand (ganglion cysts first)
giant cell tumour of the tendon sheath
what is the histology of a giant cell tumour
contain multinucleated giant cells and haemosiderin (gives brown appearance)
