Hand and wrist disorders Flashcards
Most common carpal to be fractured
Scaphoid
Who are scaphoid fractures common in?
Adolescents and young adults
How do scaphoid fractures occur?
FOOSH
hyperextension and impaction of scaphoid against radius or direct axial loading of scaphoid
Presentation scaphoid fracture
Pain in anatomical snuff box
Exacerbated by moving wrist
Swelling around radial wrist
Common location scaphoid fracture
Waist of scaphoid
can occur proximal pole and distal pole (scaphoid tubercle
X-ray scaphoid fracture
May not show up initially
Need follow up x-ray 10-14 days after (visible after bone resorption)
If still not visible but symptomatic, CT/MRI
Blood supply scaphoid
Retrograde blood supply - distal pole supplied before proximal
Avascular necrosis can occur in proximal scaphoid during waist fracture
What do waist fractures have high risk of (due to retrograde blood supply)?
Non union Malunion Avascular necrosis late: carpal instability Osteoarthritis
when is osteoarthritis common post scaphoid fracture?
If non union, malunion or avascular necrosis
What is colles fracture?
Extra-articular fracture of distal radial metaphysis
dorsal angulation (of distal segment)
impaction
What can occur alongside colles fracture?
Ulnar styloid fracture (50% cases)
Most common type distal radial fracture
Colles
Who is most at risk colles fracture?
Osteoporosis
–> Post menopausal women
(if younger, high impact)
How does colles fracture occur?
FOOSH
Pronated forearm
Dorsiflexed wrist
Patient presentation colles fracture
Painful
deformed
swollen wrist
Colles fractures treatment
Reduction and immobilisation in cast
Deformity colles fracture
Malunion = dinner fork deformity (hand curled up and then down)
Complications colles fracture
Malunion (dinner fork)
Median nerve palsy
Post traumatic carpal tunnel syndrome
Tear of extensor pollucis longus tendon (tendon over sharp fragment of bone)
Smith fracture - what is it
Fractures of distal radius with volar (palmar) angulation of distal fragments
What can smiths fracture be thought as
85% extraarticular - reverse colles fracture
Who is most at risk smiths fractures?
Young males
Elderly females
How can smith fracture occur?
Fall onto dorsum of hand when wrist flexed
Direct blow to back of wrist
What deformity can malunion of smiths fracture result in?
Garden spade - volar displacement
can narrow and distort carpal tunnel and cause carpal tunnel syndrome
Where does rheumatoid arthritis commonly occur in the hand?
MCPJ
PIPJ
What is RA?
Autoantibodies known as rheumatoid factor attack the synovial membrane
Inflamed synovial cells form pannus
Pannus erodes cartilage and bone
How is rheumatoid arthritis described?
Symmetrical polyarthritis - affects multiple joints symmetrically
Problem with symmetrical arthritis
Swelling symmetrical
Difficult to diagnose as no reference to ‘normal’ to compare to
Presentation RA
Pain/swelling MCPJ/PIPJ erythema overlying joints stiffness (worse morning/inactivity) carpal tunnel syndrome (from synovial swelling) fatigue and flu-like symptoms RA rheumatoid nodules
Rheumatoid nodules
Late presentation
Fingers and elbow
seen less frequently now
RA x ray features
Loss of joint space
Marginal bony Erosions (juxta-articular)
Subluxation/deformity
Osteopenia
(soft tissue swelling too)
Deformities associated with RA
Swan neck
Boutonniere
Swan neck
MCPJ flexed
PIPJ hyperextends
DIPJ flexed
(down, up, down)
What happens to tissues swan neck?
Palmar aspect (volar) tissues become lax from adjacent synovitits
What can occur to tendon in swan neck?
Rupture of insertion of extensor digitorum (distal phalanx) which can result in mallet deformity
What is Boutonniere?
MCPJ extended
PIPJ flexed
DIPJ extended
(up down up, opposite to swan)
What occurs during boutoniere deformity?
Rutpture/lengthening of central slip of extensor digitorum
Lateral bands can slip down the side of finger to palmar surface
can start to act as flexors at PIPJ
Psoriatic athropathy
Psoriasis results in this (small minority)
What is psoriasis?
Skin condition
red, flaky patches of skin
silvery scales
(elbows, knees, scalp and lower back commonly)
Psoriasis arthritis signs
Asymmetrical oligoarthritis (one joint at a time, then progressing asymmetrical manner. eg left big toe and then right index finger)
Where is psoratic arthiritis common?
Small joints of hands and feet
Presentation of psoriatic arthiritis
Fusiform (sausage shaped) swollen digits - aka dactylitis
Distal affected joints
Can progress to widespread destruction - arthritis mutilans
Nail lesions
What joints does psoriatic arthiritis affect?
DIPJ (unlike RA)
Nail lesions psoriatic arthiritis
Pitting
Oncholysis (seperation from nail bed)
Joint mostly affected by OA in hand
1st carpometacarpal joint (trapezium and 1st metacarpal)
OA in hand common risk people
Women
Presentation OA hand
Pain at base of thumb - exacerbated by movement, relieved by rest
Stiffness increases after rest (morning)
Swelling at base of thumb - loss of squaring/contour of hand
OA in fingers presentation
5th/6th decade of life
gradual pain DIPJ
Node sign of OA
Heberdens nodes
Affect DIPJ
women >, middle aged, genetic?
How do herbedens nodes progress symptoms?
Chronic swelling of joints
Sudden pain
Loss of dexterity
herbedens nodes growth
Cystic swelling - gelatinous hyaluronic acid dorsolateral DISTAL IPJ
Inflammation and pain subside - left with osteophyte
Other node
Same as herbedens process but in PIPJ = Bouchards
Carpal tunnel syndrome =
Compression of median nerve as it passes through carpal tunnel from forearm to hand
Risk factors carpal tunnel syndrome
Obesity Repetitive wrist work Pregnancy RA Hypothyroidism
What can carpal tunnel syndrome lead to?
Ischaemia
Focal demyelination
decrease in axonal calibre
axonal loss
Presentation carpal tunnel syndrome
Parasthesia of median nerve (thumb, index finger, middle finger, radial half ring finger)
Worse at night (wrist flexes)
Daily activities (driving/brushing hair) can worsen
What sensation is spared in carpal tunnel syndrome?
Palmar sensation - palmar cutaneous branch of median nerve branches before carpal tunnel so passes superficial to it
Muscles affected carpal tunnel syndrome
Atrophy/weakness of Thenar muscles - motor branch median nerve exits distal to carpal tunnel so affected
Thenar muscles
Flexor pollucis brevis
Opponens brevis
abductor pollucis brevis
What action of thumb will patient be able to do with carpal tunnel syndrome?
Still able to flex thumb (even though part of flexor pollucis brevis has lost supply)
Flexor pollucis longus is innervated before carpal tunnel (anterior interosseus branch median nerve)
Deep head of flexor pollucis brevis is also UNAFFECTED (ulnar nerve)
Adduction is spared as adductor pollucis is supplied by ulnar nerve
What actions are lost during carpal tunnel syndrome?
Manual dexterity (eg buttoning up shirt) is lost
Pain carpal tunnel syndrome
Proximal forearm, elbow, shoulder and neck
Where can ulnar nerve be compressed?
Guyons canal
Where does ulnar nerve pass in guyons canal where it can be compressed?
Radial/lateral to pisiform and over flexor retinaculum
Ulnar nerve compression =
Ulnar tunnel syndrome
Guyons canal syndrome
Handlebar palsy (wrists on handlebars = compressed)
Ulnar nerve compression presentation
Parasthesia in ring/little fingers
Weakness of intrinsic hand muscles (adductor pollicis, palmar and dorsi interossei, lumbricles - ring and little finger)
What is Dupuytren contracture?
Localised thickening and contracture of palmar aponeurosis leading to flexion of adjacent fingers
Process Dupuytren contracture
Nodule on palm - painful/painless
Myofibroblasts within nodule contract = tight bands called cords in palmar fascia
Overlying skin (tight to fascia) becomes involved
Proximal fascia and skin on fingers involved
Fingers stuck in flexed position
Common digits Dupuytren contracture
Ring and little finger (first webspace/thumb may be invoved)
Common people affected dupuytren
Males 40-60 years old
Northern europe
Family history - Autosomal dominant
Conditions that increase risk of Dupuytrens contracture
Type 1 diabetes Adhesive capsulitis (frozen shoulder)# Epilepsy Liver disease/excessive alcohol consumption Smoking Hypercholestrolaemia Heart disease HIV Hypo/hyperthroidism Trauma Vibration injury
injury to radial nerve in radial groove - upper arm effects
If injured in mid shaft fracture of humerus, it travels in radial/spiral groove so could be damaged
Triceps will still be intact as already branched (long and lateral prior to groove, short proximal to fracture)
Aconeus will lose supply
But still able to extend arm
injury to radial nerve in radial groove - lower arm effects
Wrist and fingers flexed
Extensors of wrist and fingers supplied by radial nerve
(when pronated)
Sensory impairment radial nerve damage in radial groove
Posterior cutaneous nerve of forearm unaffected (already branched)
Lower lateral cutaneous nerve unaffected (already branched)
Paraesthesia in superficial branch of radial nerve = lateral 3 1/2 dorsum hand (not finger tips)
High median nerve injury
No muscular branches to arm - all just before medial epicondyle
If supracondylar fracture occurs - all these muscles affected (anterior forearm)
Pronation and flexion weakened (except flexor carpi ulnaris and ulnar half of flexor digitorum profundus)
Arm position high median nerve injury
Supinated (supinator and biceps brachii)
Adduction (flexor carpi ulnaris pulls)
thumb high median nerve injury
Flexion thumb = weak (still have deep flexor pollucis brevis)
opposition and abduction of thumb = absent
Fingers high median nerve injury
Flexor digitorum superficialis = paralysed
flexor digitorum profundus (index and middle finger) paralysed
MCPJs can still flex as interossei (ulnar nerve) can work
Fist of median nerve injury
Ring and little fingers can flex to palm normally - ulnar nerve supply of FDP and lumbricles
Index and middle fingers = fully extended
Position thumb median nerve injury
IPJ's and MCPJ = extended (extensor pollucis longus is unapposed) Thumb = adduction (unapposed adductor pollucis, abductor pollucis = lost supply) Lateral rotation (loss of opponens pollucis)
Muscles intrinsic hand supplied by median nerve
LOAF Lateral lumbricals Opponens pollicis Abductor pollucis brevis Flexor pollucis brevis
Clinical sign of fist of median nerve damage known as
Hand of Benediction (flexed ring and little finger, other s extended)
ONLY SEEN WHEN TRYING TO MAKE FIST
NOT AT REST
Long term median nerve damage =
Ape hand deformity
Thenar wasting
Injury to median nerve at the wrist cause
Penetrating (eg glass) or compression of carpal tunnel
Presentation low median nerve injury
Innervation of common flexor origin = intact
Palmar cutaneous sensory branch to palm = spared
Muscles paralysed in lower median nerve injury
LOAF
Lateral lubricles (index and middle finger)
Opponens pollucis
Abductor pollucis brevis
Flexor pollucis brevis (superficial head)
Thenar eminence atrophied =
Ape hand deformity (thumb adducted and laterally rotated)
Ulnar nerve injury at wrist muscles/area spared
Flexor carpi ulnaris
Flexor digitorum profundus (ulnar half)
Palmer cutaneous branch (ulna edge of palm, already branched)
Ulnar nerve damage muscles injured
Hypothenar eminence:
Opponens digiti minimi
Flexor digiti minmi brevis
Abductor digiti minimi
adductor pollicis
dorsal/palmer interossei
Medial Lumbricles - little and ring finger
palmaris brevis
Long standing ulnar nerve damage
Claw hand - affects little and ring fingers (looks like sign of benediction)
2 fingers extended at MCPJ and flexed at IPJ’s
Why do you get claw hand with ulnar nerve damage?
Lumbricals 3 and 4 are paralysed (1 and 2 are intact - median nerve)
Lumbricles flex at MCPJ and extend at IPJ’s
= MCPJ unapposed extension from extensor digitorum
= IPJ’s unapposed flexion from long flexor FDP and FDS
(extensor digitorum cannot appose FDP and FDS as energy dissipated at MCPJ)
What does wasting of interossei, hypothenar and adductor pollucis result in?
Interossei - guttering between metacarpals
1st interossei and adductor pollucis = loss of bulk of first webbed space
Hypothenar = loss of bulk of hypothenar
Injury to ulnar nerve at elbow =
All muscles/skin innervated by ulnar nerve (discussed in other card)
+ flexor carpi ulnaris, flexor digitorum profundus (ulnar section) and loss of sensation of palmar nerves
Explain ulnar paradox
Proximal nerve injury gives more pronounced claw sign
(you would think distal = larger effects but NO)
In distal, flexor digitorum profundus (ulnar part) is also paralysed so no flexion occurs at DIPJ of ring and little finger
