2.06 - Trauma and Orthopaedics - The Wrist and Hand Flashcards
Which nerve is affected in carpal tunnel syndrome?
Median nerve is compressed within the carpal tunnel of the wrist, due to a raised pressure within the compartment.
What are the risk factors for carpal tunnel syndrome?
- female gender
- increasing age
- pregnancy
- obesity
- previous injury to the wrist
What are the clinical features of carpal tunnel syndrome?
Throughout the median nerve sensory distribution, the patient will present with:
- pain
- numbness
- paraesthesia
In later stages of CTS, there may be weakness of thumb abduction and wasting of the thenar eminence, due to denervation atrophy of the thenar muscles.
Why is the palm often spared in carpal tunnel syndrome?
The palm is innervated by the palmar cutaneous branch of the median nerve, which branches proximal to the flexor retinaculum and therefore passes over the carpal tunnel.
What are the special tests that can be used to diagnose carpal tunnel syndrome?
Tinel’s test - positive if symptoms reproduced by percussing over the median nerve.
Phalen’s test - positive if symptoms reproduced by holding the wrist in full flexion for one minute.
What are some differentials for carpal tunnel syndrome?
- C6 radiculopathy
- pronator teres syndrome
- flexor carpi radialis tenosynovitis
How is carpal tunnel syndrome investigated?
Usually a clinical diagnosis, based upon history and examination findings.
In uncertain cases, nerve conduction studies may be useful to confirm median nerve damage.
What is the conservative management of carpal tunnel syndrome?
- wrist splint
- hand therapy
- corticosteroid injections into the carpal tunnel
What is the surgical management of carpal tunnel syndrome?
Carpal tunnel release surgery decompresses the carpal tunnel.
Involves dissecting the flexor retinaculum, in turn reducing pressure on the median nerve.
When is surgical treatment of carpal tunnel syndrome indicated?
Undetaken in a symptomatic patient, where previous conservative treatments have not been successful
What are the complications of carpal tunnel release surgery?
- recurrence
- persistent symptoms
- infection
- scar formation
- nerve damage
- trigger thumb
What are the complications of long-term untreated carpal tunnel syndrome?
Neurological impairment
What tissue in particular is affected by Dupuytren’s contracture?
Contraction of the longitudinal palmar fascia
Explain the pathophysiology of Dupuytren’s contracture.
Fibroplastic hyperplasia and altered collagen matrix of the longitudinal palmar fascia leads to a thickening and contraction of the fascia.
Contraction of the fascia pulls on the MCP and PIP joints, leading to a progressive flexion deformity in the fingers.
What are the risk factors for Dupuytren’s contracture?
- smoking
- alcoholic liver cirrhosis
- diabetes mellitus
- occupational exposures (e.g. use of vibrational tools)
What investigations can be used to diagnose Dupuytren’s contracture?
Diagnosis usually clinical, but can us USS for increased accuracy in applying intralesional injections.
Patients should ideally have routine bloods including LFTs and HbA1C to assess for associated risk factors.
What is the management of Dupuytren’s contractures?
Conservative measures:
1. Hand therapy, to keep the hand active with stretching exercises.
2. Injectable CCM
Surgical management:
1. Fasciectomy of diseased fascia
2. Finger amputation - rarely required
When is surgical management of Dupuytren’s contracture indicated?
- functional impairment
- MCP joint contracture >30°
- PIP contracture
- rapidly progressing disease
What is De Quervain’s tenosynovitis?
Inflammation in the tendons within the first extensor compartment of the wrist, resulting in wrist pain and swelling.
Compartment 1: extensor pollicis brevis and abductor pollicis longus.
What are the risk factors for De Quervain’s tenosynovitis?
- age (30-50yo)
- female gender
- pregnancy
What are the clinical features of De Quervain’s tenosynovitis?
- pain near base of thumb
- associating swelling
- painful grasping / pinching
OE swelling and palpable thickening over tendon group.
What is the management of De Quervain’s tenosynovitis?
Lifestyle advice:
- avoid repetitive actions
- wrist splint
- steroid injections
Surgical decompression of extensor compartments
What are ganglionic cysts?
Non-cancerous soft tissue lumps that occur along any joint or tendon, most commonly found in the hands and feet.
They arise from degeneration within the joint capsule or tendon sheath of the joint, becoming filled with synovial fluid.
What are the risk factors for ganglionic cysts?
- female gender
- osteoarthritis
- previous joint or tendon injury
Give the clinical features of ganglionic cysts.
- painless lump
- appeared suddenly or grown over time
OE lump will be soft and will transilluminate. If cyst exerts pressure upon adjacent nerves, patient may present with localised paraesthesia, pain or motor weakness.
What are some differential diagnoses to ganglionic cysts?
- tenosynovitis
- lipoma
- osteoarthritis
- sarcoma
What investigations can be used to investigate ganglionic cysts?
Usually a clinical diagnosis.
Plain film radiograph can be used to exclude OA or bone malignancies.
Imaging via ultrasound or MRI may be used.
How are ganglionic cysts managed?
Usual recommended treatment is to monitor, as cysts often disappear spontaneously without further intervention.
If cyst causes pain or severely limits range of movement:
- aspiration of cyst
- steroid injection
- cyst excision
What is the pathophysiology of trigger finger?
Flexor tenosynovitis at the metacarpal head results in inflammation of the flexor tendon and sheath, forming a node.
The node can become trapped within the pulley, causing the digit to become locked in a flexed position.
What are the risk factors for trigger finger?
- prolonged gripping
- rheumatoid arthritis
- diabetes mellitus
- female gender
- increasing age
What are the clinical features of trigger finger?
- painless clicking when trying to extend finger
- digits lock in flexion
What is the management of trigger finger?
- small splint to hold finger in extension position
- steroid injections
- percutaneous trigger finger release
- surgical decompression of tendon tunnel
What is the most commonly fractures carpal bone?
Scaphoid
Describe the blood supply to the scaphoid bone.
Branches of he radial artery supplies the scaphoid bone, entering at the distal pole and travelling in a retrograde fashion towards the proximal pole of the scaphoid.
What is a common vascular complication of scaphoid fractures?
Avascular necrosis of the scaphoid is more common in proximal scaphoid fractures, due to the retrograde blood supply via branches of the radial artery.
What are the clinical features of scaphoid fractures?
- fractured following trauma
- sudden onset wrist pain
- tenderness in floor of anatomical snuffbox
- pain on palpating scaphoid tubercle
- pain on telescoping of the thumb
How can suspected scaphoid fractures be investigated?
- plain film radiographs (AP / lateral / oblique)
- repeat radiograph after 2/52
- MRI imaging
How are scaphoid fractures managed?
- strict immobilisation if undisplaced
- operative fixation is displaced or fractured at the proximal pole
What is the common mechanism of injury of distal radius fractures?
FOOSH causing forced supination or pronation of the carpus.
What is a Colles’ fracture?
An extra-articular fracture of the distal radius with dorsal angulation and dorsal displacement.
MOI FOOSH forwards.
What is a Smith’s fracture?
An extra-articular fracture of the distal radius with volar angulation.
MOI FOOSH backwards.
What is a Barton fracture?
An intra-articular fracture of the distal radius with associated dislocation of the radio-carpal joint.
What are the risk factors for distal radius fractures?
- osteoporosis
- increasing age
- female gender
- early menopause
- smoking
- alcohol excess
- prolonged steroid use
What are the clinical features of distal radius fractures?
- trauma
- immediate pain / deformity
- neurological involvement causing pain, paraesthesia or paralysis
- neurovascular compromise
Which nerves in particular should be assessed when suspecting a distal radius fracture?
Median nerve - abduction of thumb (m) & radial surface of second digit (s)
Ulnar nerve - adduction of thumb (m) & ulnar surface of distal fifth digit (s)
Radial nerve - extension of IPJ of thumb (m) & dorsal surface of first webspace (s)
How are distal radius fractures investigated?
- plain film radiograph
- CT or MRI for operative planning
How are distal radial fractures managed?
- closed reduction
- MUA
- below elbow backslab cast
If displaced / unstable, surgical intervention required:
- ORIF with plating
- K-wire fixation
What are the main complications of distal radius fracture?
- malunion
- median nerve compression
- osteoarthritis
