Common Conditions Of The Hand And Wrist Flashcards
Where do patients with a scaphoid fracture most commonly complain of pain?
The anatomical snuff box
Describe the distribution of the most common scaphoid fractures
- 70-80% occur at the scaphoid waist
- 20% at the proximal pole
- 10% at the distal pole
Why can fractures through the scaphoid waist cause avascular necrosis?
Blood supply is retrograde from the distal to proximal pole so proximal end can loose blood supply when broken
What is a Colle’s fracture?
An extra-articular fracture of the distal radial metaphysis, with dorsal angulation and impaction
What group of people are Colle’s fractures most common in?
Common in patients with osteoporosis, especially post-menopausal women
Describe how a Colle’s fracture looks
Looks like a dinner fork
Dorsally angulated and impacted
What is a Smith’s fracture
A fracture of the distal radius with palmar angulation of the distal fracture
How do smith’s fractures usually occur?
FOOSH onto a flexed wrist
What cosmetic deformity can result from a Smith’s fracture
With malunion of a Smith’s fracture you see garden spade deformity → residual volvular displacement
It can cause carpal tunnel syndrome
Which joints does rheumatoid arthritis mainly affect?
The metacarpophalangeal (MCPJ) and the proximal interphalangeal joints (PIPJ)
Give 4 X-ray features of rheumatoid arthritis
- Joint space narrowing
- Periarticular osteopenia (evidence of inflammation)
- Marginal bony erosions
- Subluxation (partial dislocation) and gross deformity
What 2 deformities will you are in a rheumatoid arthritis hand?
- Swan neck deformity
- Boutonniere deformity
What happens to the finger joints to cause swan neck deformity
The PIP joint hyperextends whilst the MCP and DIP joints are flexed
What happens to the finger joints in BOUTONNIERRE deformity
The MCP joint and DIP joints are hyperextended whilst the PIP joint is flexed
What is psoriatic arthropathy?
Arthritis developing in a minor proportion of patients who have psoriasis
Which joints are more commonly affected in psoriatic arthropathy?
The DIP joints (Opposite to RA)
How does psoriatic arthropathy present?
Patient will have:
- fusiform (sausage shaped) swelling of digits called dactylitis
- affected joints are stiff
- 80% of patients have nail lesions e.g. pitting and onycholyosis (separation of nail from the nail bed)
Which joint of the hand is most commonly affected by osteoarthritis?
The 1st carpometacarpal joint (between the trapezium and 1st metacarpal)
What happens in late stage osteoarthritis of the 1st CMC joint?
The 1st metacarpal subluxes in an ulnar direction Causes the hand to ‘square’
What are Heberden’s nodes?
A sign of osteoarthritis affecting the DIP joints
- chronic swelling of affected joint
- loss of manual dexterity
- initial cyst develops containing hyaluronic acid
- once initial inflammation subsides the patient is left with an osteophyte
What are Bouchard’s nodes?
The same as Heberden’s nodes but in the PIP joint
What is carpal tunnel syndrome?
Compression of the median nerve as it passes through the carpal tunnel in the forearm into the hand
What will a patient with carpal syndrome complain of?
- Paraesthesia in the distribution of the median nerve (thumb, index finger, middle finger and radial half of the ring finger)
- Symptoms often worse at night
- Daily activities can aggregate the pain
Why does long standing carpal tunnel syndrome cause muscle wasting of the thenar muscles? (OAF)
The motor branch of the median nerve that supplies the thenar muscles branches distally to the carpal tunnel and is therefore compressed in carpal tunnel syndrome
What nerve is compressed in Guyon’s canal?
What is the syndrome called?
The ulnar nerve - known as ulnar tunnel syndrome,
Guyon’s canal syndrome or Handlebar palsy
Where will the patient report paraesthesia in Guyon’s canal syndrome?
In the ring and little fingers
Will also affect the adductor pollicis, palmar and dorsal interossei, and lumbricals of the ring and little fingers
What is Dupuytren’s contracture?
Localised thickening and contracture of palmar aproneurosis leading to a flexion deformity of adjacent fingers
Will a patient be able to extend their elbow in fracture of the mid shaft of the humerus? Explain your answer
Yes extension will be normal
The radial nerve branch that supplies the triceps is given off before the radial nerve enters the spiral groove
If the radial nerve is damaged in humeral fracture, what position will the patients wrist and fingers be in when the wrist is pronated?
Wrist and fingers will be flexed known as wrist drop
Radial nerve paralysis of brachioradialis and all extensor muscles of the wrist and fingers
Describe the distribution of sensory impairment in radial nerve damage due to humerus fracture
In the area innervated by the superficial radial nerve branch
i.e. thumb, index, middle and half of ring finger (posteriorally) NOT including the finger tips
If the median nerve is damaged in a supracondylar fracture, explain how the hand may look and why
The Hand of Benedicition
Flexor digitorum superficialis is paralysed in all 4 fingers. Flexor digitorum profundus is only paralysed in the index and middle fingers. Flexor Policis Longus is also paralysed
When asked to make a fist, only the ring and little finger can flex
How would the hand appear in an low injury to the median nerve (i.e. at the wrist)
Ape hand deformity
Flattening of the thenar emnince, thumb is adducted and externally rotated
Appearance is different from a supracondylar fracture injury to median nerve as the branches supplying muscles of the forearm have already branched
How may the hand appear in an injury to the ulnar nerve at the wrsit (low ulnar injury). Explain why
Ulnar Claw
- The ring and little fingers of the hand are flexed at the PIP and DIP joints due to unnapposed flexion from flexor digitorum superficialis and flexor digitorum profundus
- They are extended at the MCP joints due to unnopposed extension from extensor digitorum
How may the hand appear in a high inury to the ulnar nerve (at the elbow)
High ulnar claw
All the muscles supplied by ulnar nerve in the hand, as well as injury to flexor carpi ulnaris and ulnar half of flexor digitorum profundus (there is no flecusion of DIPJ of the ring and little fingers)
