HAND & ARM Flashcards
What are the 3 types of bones in the hands?
Carpal bones
Metacarpal bones
Phalanges
What are the carpal bones?
Scaphoid
Lunate
Triqetrum
Pisiform
Trapezium
Trapezoid
Capitate
Hamate
“Some Lovers Try Positions That They Can’t Handle”
Which of the carpal bones is a sesamoid bone?
The pisiform - it is formed within the tendon of the flexor carpi ulnaris
What are the metacarpal bones?
Metacarpal 1-5 for each finger
They articulate proximally with the carpals and distally with the proximal phalanges
What are the phalanges?
Bones of the fingers
Each digit has a proximal, middle and distal phalanx apart from the thumb which only has a proximal and distal phalanx.
What are the extrinsic and intrinsic muscles of the hand?
Extrinsic - located in anterior and posterior compartments of the forearm. Control crude movements and produce a forceful grip
Intrinsic - located within the hand itself. Responsible for the fine motor functions of the hand
What innervates the thenar muscles?
Median nerve
What are the thenar muscles?
Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis
Function of opponens pollicis?
Opposes the thumb by medially rotating and flexing the metacarpal on the trapezium
Function of abductor pollicis brevis?
Abducts the thumb
Function of flexor pollicis brevis?
Flexes the MCP joint of the thumb
What innervates the hypothenar eminence?
Ulnar nerve
What are the hypothenar muscles?
Opponens digiti minimi
Abductor digiti minimi
Flexor digiti minimi brevis
Function of opponens digiti minimi?
Rotates the metacarpal of the little finger towards the palm, producing opposition
Function of abductor digiti minimi?
Abducts the little finger
Function of flexor digiti minimi brevis?
Flexes the MCP joint of the little finger
What innervates the lumbricals?
Lateral 2 - median nerve
Medial 2 - ulnar nerve
What hand muscles does the median nerve innervates?
LOAF
The lateral 2 lumbricals, opponens pollicis, abductor pollicis brevis and flexor pollicis brevis
All others are ulnar
Function of the lumbricals?
Flexion at MCPJ and extension at IPJs of each digit
Denervation of the lumbricals causes what…?
Ulnar claw
Hand of benediction
What is hand of benediction?
When there is a lesion of the median nerve so the middle and index fingers cannot flex at the MCP and IP joints
This is due to paralysis of the lateral 2 lkmbricals and the lateral half of flexor digitorum profundus
What is ulnar claw?
Lesion of an ulnar nerve which causes unopposed extension at the MCPjs and flexion at IPJs in the little and ring fingers
This is due to paralysis of the medial 2 lumbricals
What are the interossei muscles?
These are the muscles located between the metacarpal bones of the hand
They are divided into dorsal and planar
What innervates the interossei muscles?
Ulnar nerve
Function of dorsal interossei muscles?
Abduction of digits
Assists in flexion at MCPJs and IPJs
Function of palmar interossei muscles?
Adduction of digits
Assists in flexion at MCPJs and extrension at IPJs
What is the palmaris brevis?
A small, thin muscle found superficially in the subcutaneous tissue of the hypothenar eminence
It originates from the palmar aponeurosis and flexor retinaculum and attaches to the dermis of the skin
What innervates palmaris brevis?
Ulnar nerve
Fnction of palmaris brevis?
Wrinkles the skin of the hypothenar eminence and deepens the curvature of the hand, improving grip
Function of adductor pollicis?
Adducts thumbs
Innervation of adductor brevis?
Ulnar nerve
What is the carpal tunnel bounded by?
Bounded on 3 sides by the carpal bones and on the palmar side by the transverse carpal tigament
What is contained within the carpal tunnel?
The median nerve and flexor tendons
Pathophysiology of carpal tunnel syndrome?
Reduction in dimensions of carpal tunnel or increase in the volume of its contents -> increased pressure in the tunnel -> ischaemia of median nerve which impairs nerve confection -> pain and paraesthesia in median nerve distribution
Risk factors for carpal tunnel syndrome?
Activities with high hand/wrist repetitive rate e.g. gardening, vibrating hand tools
Obesity
Pregnancy
OA of MCP joint of thumb (due to osteophytes)
Inflammatory joint disease e.g. RA
Ganglion cysts
Scar tissue e.g. lunate fracture
Hypothyroidism
DM
Oedema e.g HF
Symptoms of carpal tunnel syndrome?
In the distribution of the median nerve (thumb, index, middle finger) there may be…
Intermittent paraesthesia, numbness, altered sensation
Burning or pain
May be worse at night
Shaking the wrist can help relieve pain
Examination signs of carpal tunnel syndrome?
Weakness of thumb abduction (abductor pollicis brevis)
Wasting of thenar eminence only
Tinels sign
Phalens sign
Durkan’s test
What is tinels sign?
tapping the wrist over the median nerve causes paraesthesia in cubital tunnel syndrome
What is phalens sign?
Flexing the wrist for 60 seconds causes paraesthesia in cubital tunnel syndrome
What is Durkan’s test?
if direct pressure over the proximal edge of the transverse carpal ligament (proximal wrist crease) with the thumbs produces or worsens paraesthesia in the median nerve distribution.
Positive in carpal tunnel syndrome
How to diagnose carpal tunnel syndrome?
Clinically
Nerve conduction studies are not usually needed but can be done if diagnosis is uncertain
What would electrophysiology studies show in carpal tunnel syndrome?
Motor and sensory prolongation of the action potential
Management of carpal tunnel syndrome?
Lifestyle changes - avoid repetitive hand/wrist movements and optimise management of underlying conditions
6 weeks trial of conservative treatment - wrist splint at night or single corticosteroid injection into carpal tunnel or hand exercises and median nerve mobilisation techniques
Specialist treatment may include carpal tunnel surgery
What surgery can be done for carpal tunnel syndrome?
Surgical decompression with a flexor retinaculum division
What is De Qervain’s tenosynovitis?
A common condition in which the sheath containing the extensor pollicis brevis and abductor pollicis longus tendons is inflamed
Who does De Qervain’s tenosynovitis most commonly affect?
Females aged 30-50
Clinical features of De Quervain’s tenosynovitis?
Pain on the radial side of the wrist
Tenderness over the radial styloid process
Abduction of the thumb against resistance is painful
What is Finkelstein’s test?
the examiner pulls the thumb of the patient in ulnar deviation and longitudinal traction. In a patient with tenosynovitis this action causes pain over the radial styloid process and along the length of extensor pollisis brevis and abductor pollicis longus
What causes De Quervain’s tenosynovitis?
Chronic overuse e.g. repetitive hand motions such as holding a baby up or jobs
Inflammatory arthritis
Direct injury to wrist or tendon
Fluid retention e.g. pregnancy
Management of De Quervain’s tenosynovitis?
analgesia
steroid injection
immobilisation with a thumb splint (spica) may be effective
surgical treatment is sometimes required
What is dupuytren’s disease?
A benign, progressive fibroproliferative disorder of the fascia of the hands and fingers that can lead to disabling contractures
What is dupuytren’s disease vs dupuytren’s contractures?
Dupuytrens disease is when there is thickening of the connective tissue in the hand to form nodules and development of cords extending towards the fingers
As the cords contract over years they can lead to flexion contracture of the fingers and when the fingers cannot be straightened its called dupuytren’s contractures
Epidemiology of dupuytren’s disease?
Affects 20% of over 65s
Most often seen in people of Northern European descent
6x more common in men
More common once over 50 in men or over 60 in women
Risk factors for dupuytren’s disease?
Increasing age
Male
Positive FH
Northern European descend
DM
Smoking
High alcohol consumption -> alcoholic liver disease
Epilepsy - particarly phenytoin treatment
Hand trauma e.g. vibration exposure
Natural history of dupuytren’s disease?
Skin of palm and underlying tissue just distal to the distal palmar crease becomes thickened
Pits and dimples may form in the skin as vertical fibres attaching the skin to the palmar fascia shorten
Small firm nodules develop in palm near distal plamar crease
Disease spreads form nodules up the fascia and into the fingers forming a cord which may attach to skin
Shorterning of the cords forces digits to flex forming a contracture
Which fingers are most likely to be affected by dupuytren’s contractures?
Fourth and fifth fingers
Prognosis of dupuytren’s disease?
Progressive and incurable
Surgical correction wont stop the disease progression
What test can be done for suspected dupytrens contracture?
The tabletop test
What is the tabletop test?
If the person is unable to lay their palm and fingers flat on a tabletop, then contracture is present
Management of dupuytren’s disease?
No Tx - explain condition to pt and that they should return if a contracture develops
Management of dupuytren’s contactre?
Refer to a hand surgeon or specialist for surgical management
Surgical procedure for dupuytren’s?
Needle fasciotomy
Fasciectomy
Dermofasciectomy
What is trigger finger?
A common condition where there is a disparity between the size of the tendon and pulleys through which they pass which result in abnormal flexion of the digits
What is trigger finger associated with?
Women
RA
DM
(Note its idiopathic in the majority of cases)
Clinical features of trigger finger?
Thumb, middle or ring finger
Stiffness and snapping when extending a flexed digit
A nodule may be felt at the base of the affected finger
Management of trigger finger?
Steroid injection
Finger splint
If unresponsive then surgery can be done
What is a ganglion?
A cyst arising from a joint or tendon sheath
Can range from the size of a pea to a golf ball
Most commonly seen around the dorsal aspect of the wrist
3x more common in women
Features of a ganglion?
A firm and well-circumciscribed mass that transiluminates
Painless
Management of ganglions?
Often disappear spontaneously after several months
Aspiration or surgical excision can be done if severe symptoms or nerovasclar manifestations
What is tennis elbow?
Lateral epicondylitis
Tendinosis that affects the common attachment of the tendons of the extensor muscles of the forearm to the lateral epicondyle of the humerus
Most common muscle affected in tennis elbow?
Extensor carpi radial is
Presentation of tennis elbow?
Dominant arm in 75% of people
Pain in lateral elbow that may radiate down or, less commonly, up arm
Pain with wrist extension and reduced grip strength
Pain is exacerbated by activities involving excessive and repetitive use of extensor muscles of forearm
Examination findings in tennis elbow?
Localised point tenderness over lateral epicondylitis
Resisted middle finger extension is painful - Maudsley’s test
Dorsiflexion wrist against resistance with elbow flexed at 90 degrees. Extending the elbow increases pain further
Reduced grip strength
Causes of tennis elbow?
Minor or unrecognised trauma o the forearm extensor muscles e.g. tennis, plumping, grip-intensive activities
Prognosis of tennis elbow?
Self-limiting that usually improves spontaneously in 90% in 1-2 years
Patients tend to have acute pain for 6-12 weeks
Management options for tennis elbow?
Rest ice analgesia
Orthosis
After 6 weeks consider referring to PT
If no response 6-12 months later -> consider referral to orthopaedic surgeon for evaluation
What is golfer’s elbow?
Medial epicondylitis
Symptoms of medial epicondylitis?
Pain and tenderness localised to medial epicondyle
Pain aggravated by wrist flexion and pronation
Symptoms may be accompanied by numbness/tingling in 4th/5th finger (ulnar nerve involvement)
What is radial tunnel syndrome?
Compressive neuropathy of the posterior interosseous branch of the radial nerve in the radial tunnel
Thought to be as a result of overuse
Symptoms of radial tunnel syndrome?
Similar to lateral epicondylitis so tricky to diagnose but…
Pain tends to be 4-5cm distal to the lateral epicondyle and symptoms are worsened by extending the elbow and pronating the forearm
What is cubital tunnel syndrome?
Compression of the ulnar nerve within the cubital tunnel and subsequent inflammation
Symptoms of cubital tunnel syndrome?
initially intermittent tingling in the 4th and 5th finger
may be worse when the elbow is resting on a firm surface or flexed for extended periods
later numbness in the 4th and 5th finger with associated weakness
May be a history of OA or prior trauma to this area
Diagnosing cubital tunnel syndrome?
the diagnosis is usually clinical
however, in selected cases nerve conduction studies may be used
Management of cubital tunnel syndrome?
Avoid aggravating activity
Splints
Physiotherapy
Steroid injections
Surgery in resistant cases
What is olecranon bursitis?
Inflammation of the bursa overlying the olecranon process of the elbow
Aka miners elbow, students elbow, draftmans elbow
Causes of olecranon bursitis?
Trauma
Overuse
Systemic conditions e.g. gout or RA
Symptoms of olecranon bursitis?
Swelling appears over hours-days, is tender or warm and is fluctuant
Movement at elbow is painless except at full flexion when swollen bursa is compressed
May be history or preceding trauma or bursal disease
Mechanism of injury for distal bicep tendon ruptures?
Flexed elbow is suddenly and forcefully extended whilst the bicep muscle is contracted already
Symptoms of distal bicep tendon rupture?
Sudden pop or tear in antecubital fossa followed by pain, bruising and swelling
Reverse pop eye deformity
Weakness in shoulder and elbow
What are osler’s nodes?
Painful, red raised lesions in hands and feet as a result of deposition of immune complexes
What are Bouchard’s nodes?
Hard, bony outgrowths or gelatinous cysts on the proximal interphalangeal joints
Sign of OA and caused by formation of calcific spurs of artiucalr cartilage
What is OA of the hand sometimes referred to as?
Nodal arthritis
Risk factors for OA of the hand?
Previous trauma of joint
Obesity
Hypermobility of a joint
Occupation e..g farmers
Presentation of OA of the had?
Bilateral - CMC, DIPJs affected the most
Episodic joint pain provoked by movement and relieved by rest
Stiffness lasts <1 hour in morning and is worse after long periods of inactivity
Heberden and bouchard’s nodes
What is erb-duchenne paralysis?
Which roots are affected? What does this cause?
What is the cause?
Aka erbs palsy
A brachial plexus injury - damage to C5 and C6 producing a winged scapula and a waiter tip appearance
May be caused by a breech position
What is klumpke’s paralysis?
What does it cause?
What causes it?
A brachial plexus injury - damage to T1
Loss of intrinsic hand muscles-> claw hand
Due to traction or traumatic birth
Mneumonic for remembering the nerves in the arm and what causes their damage?
ARM-U
NAMe SOME
Axillary nerve (C5/C6) - Neck of humerus fracture
Radial nerve (C5-T1) - Axilla compression or Midshaft fracture
Median nerve (C5-T1) - Supracondylar fracture
Ulnar nerve (C8-T1) - Outstretch hand fall, Medial Epicondyle
Axillary - Abduct
Radial - Rist drop
Median - Monkey ape hand (thumb is permenantly rotated and adducted resting in a lost of its opposable function)
Ulnar - ulnar claw
What is saturday night palsy?
Compressive radial mononeuropathy
Falling asleep with the arm hanging over a chair or hard surface leading to compression of the radial nerve
Causes wrist drop and numbness in dorsal area of hand just proximal to thumb
