Orthopaedics Flashcards
What are the LOAF muscles?
Lateral two lumbricals
Opponens pollis
Abductor pollis brevis
Flexor pollis brevis
What’s another name for frozen shoulder?
Adhesive capsulitis
Who does adhesive capsulitis normally affect and what conditions is it associated with?
Middle aged women (50s)
- Diabetes mellitus: up to 20% of diabetics may have an episode of frozen shoulder
- Trauma
- steroids
- endocirnopathies
What are the features of adhesive capsulitis?
- external rotation is affected more than internal rotation or abduction
- both active and passive movement are affected
- patients typically have a painful freezing phase (6 months), an adhesive phase/stiff phase (1 year) and a recovery phase (6-12 months)
- bilateral in up to 20% of patients
- the episode typically lasts between 6 months and 2 years
What’s the management for frozen shoulder?
- no single intervention has been shown to improve outcome in the long-term
- treatment options include NSAIDs, physiotherapy, oral corticosteroids and intra-articular corticosteroids
- reassure that it is self resolving
What’s the management for dupuytren’s contracture?
Consider surgical treatment or injectable enzyme therapy when the metacarpophalangeal joints cannot be straightened and thus the hand cannot be placed flat on the table
- needle fasciotomy
- fasciectomy
- collagenase
What is the pathophysiology of dupuytren’s contracture?
What is it associated with?
- Painless thickening of the skin/fascia with skin puckering and tethering on palmar aspect
- particularly affects the little and ring fingers
- often bilateral and symmetrical
- MCP joints can be affected
- manual labour
- phenytoin treatment
- alcoholic liver disease
- trauma to the hand
What’s the prevalence of dupuytren’s contracture? Who is normally affected?
5%. It is more common in older male patients and around 60-70% have a positive family history
What is cauda equina and what causes it?
- compression of cauda equina
- abcess
- central lumbar disc prolapse
- extrinsic/intrinsic tumours of spine/cord
- spondylosis
- spinal stenosis
- trauma
- spinal SAH
- vertebral collapse
What are the symptoms of cauda equina?
- back pain
- lower limb weakness/sensory loss
- altered perineal/perianal sensation
- sphincter disturbance (incontinence or retention)
How do you manage back pain?
Advice to people with low back pain
- try to encourage self-management
- stay physically active and exercise
Analgesia
- NSAIDS are now recommended first-line for patients with back pain. This follows studies that show paracetamol monotherapy is relatively ineffective for back pain
- proton pump inhibitors should be co-prescribed for patients over the age of 45 years who are given NSAIDs
- NICE guidelines on neuropathic pain should be followed for patients with sciatica
What should you do if you suspect cauda equina?
- DRE
- MRI within 4 hours
Which neurovascular structure that is compromised in a scaphoid fracture?
The dorsal carpal branch of the radial artery
A scaphoid fracture typically occurs as a result of which injury?
- fall onto an outstretched hand (FOOSH)
- contact sports
- during a road traffic accident due to the patient holding the steering wheel
resulting in axial compression of the scaphoid, with the wrist hyper-extended, and radially deviated.
Who is most likely to get a scaphoid fracture?
- Males are at increased risk of fracture (7M:1F).
- The average age of the patient is 22 years old (9 to 35 years old).
- The reported incidence for fracture of the scaphoid is 12.4 per 100,000.
If you have all the symptoms of a hip fracture but it doesn’t show on Xray what should you do?
MRI
What are the features of a hip fracture?
- pain
- shorter and externally rotated leg
How do you classify hip fractures?
Location
- intracapsular (subcapital): from the edge of the femoral head to the insertion of the capsule of the hip joint
- extracapsular: these can either be trochanteric or substrochanteric (the lesser trochanter is the dividing line)
The Garden system is one classification system in common use.
- Type I: Stable fracture with impaction in valgus
- Type II: Complete fracture but undisplaced
- Type III: Displaced fracture, usually rotated and angulated, but still has boney contact
- Type IV: Complete boney disruption
Blood supply disruption is most common following Types III and IV.
How do you treat a hip fracture?
Intracapsular hip fracture:
- Undisplaced Fracture:
- internal fixation (DHS), or hemiarthroplasty if unfit. 10% chance of head dying. - Displaced Fracture:
- young and fit i.e. <70 years- Reduction (still using own femoral head) and internal fixation (DHS/cannulated hip screws)(if possible). 40% chance of head dying
- older and reduced mobility- Hemiarthroplasty or total hip replacement (10% chance of dislocation with THR. If this is too great then do a hemiarthroplasty as ball is much bigger).
Extracapsular hip fracture
- dynamic hip screw
- if reverse oblique, transverse or subtrochanteric: intramedullary device
What’s the condition?
The x-ray shows extensive bone remodeling / fragmentation involving the midfoot. In combination with the presence of a swollen, red, warm joint in a patient with a history of poorly controlled diabetes is highly suggestive of ….
a Charcot’s joint (neuropathic joint)
It describes a joint which has become badly disrupted and damaged secondary to a loss of sensation.
What’s the most common cause of a Charcot joint?
In years gone by they were most commonly caused by neuropathy secondary to syphilis (tabes dorsalis) but are now most commonly seen in diabetics.
Describe Colles’ fracture
(dinner fork deformity)
Fall onto extended outstretched hand
Classical Colles’ fractures have the following 3 features:
- Transverse fracture of the radius
- 1 inch proximal to the radio-carpal joint
- Dorsal displacement and angulation
Describe Smith’s fracture
(reverse Colles’ fracture)
- Volar angulation of distal radius fragment (Garden spade deformity)
- Caused by falling backwards onto the palm of an outstretched hand or falling with wrists flexed
Describe Bennett’s fracture
- Intra-articular fracture of the first carpometacarpal joint
- Impact on flexed metacarpal, caused by fist fights
- X-ray: triangular fragment at ulnar base of metacarpal
Describe Monteggia’s fracture
mont- a- ga
- Dislocation of the proximal radioulnar joint in association with an ulna fracture
- Fall on outstretched hand with forced pronation
- Needs prompt diagnosis to avoid disability
MUgGeR:
MonteggiA= ulnar, A= proximal
GaleaZzi= radial, Z= distal
Describe Galeazzi fracture
gil-e-art-zi
The opposite of a Monteggia fracture
- Radial shaft fracture with associated dislocation of the distal radioulnar joint
- Direct blow
MUgGeR:
MonteggiA= ulnar, A= proximal
GaleaZzi= radial, Z= distal
Describe Pott’s fracture
- Bimalleolar ankle fracture
- Forced foot eversion
Describe Barton’s fracture
- Distal radius fracture (Colles’/Smith’s) with associated radiocarpal dislocation
- Fall onto extended and pronated wrist
Which nerve is at risk in the Lloyd-Davies position?
Peroneal
Inguinal hernia repair can damage which nerve?
Ilioinguinal nerve
What are the muscles in the anterior compartment of the lower leg? Which nerves innervate them and what is their function?
Tibialis anterior
- Deep peroneal nerve
- Dorsiflexes ankle joint, inverts foot
Extensor digitorum longus
- Deep peroneal nerve
- Extends lateral four toes, dorsiflexes ankle joint
Peroneus tertius
- Deep peroneal nerve
- Dorsiflexes ankle, everts foot
Extensor hallucis longus
- Deep peroneal nerve
- Dorsiflexes ankle joint, extends big toe
What are the muscles in the peroneal compartment of the lower leg? Which nerves innervate them and what is their function?
Peroneus longus
- Superficial peroneal nerve
- Everts foot, assists in plantar flexion
Peroneus brevis
- Superficial peroneal nerve
- Plantar flexes the ankle joint
What are the muscles in the superficial posterior compartment of the lower leg? Which nerves innervate them and what is their function?
Gastrocnemius
- Tibial nerve
- Plantar flexes the foot, may also flex the knee
Soleus
- Tibial nerve
- Plantar flexor
What are the muscles in the deep posterior compartment of the lower leg? Which nerves innervate them and what is their function?
Flexor digitorum longus
- Tibial
- Flexes the lateral four toes
Flexor hallucis longus
- Tibial
- Flexes the great toe
Tibialis posterior
- Tibial
- Plantar flexor, inverts the foot
What actions do the lumbricals do?
flex the metacarpal phalangeal joints (MCPJ) and extend the interphalangeal joints (IPJ)
What causes clawing of the medial two fingers?
When the ulnar nerve is damaged at the wrist, the medial two lumbrical muscles are affected (the lateral two being supplied by the median nerve). Denervation of the lumbricals, which flex the metacarpal phalangeal joints (MCPJ) and extend the interphalangeal joints (IPJ), causes unopposed extension of the MCPJ by extensor digitorum longus and flexion of the IPJ by flexor digitorum profundus and superficialis. This gives the hand a claw like appearance.
What’s the function of the femoral nerve?
From what is it derived?
Motor functions: Innervates the anterior thigh muscles that:
- flex the hip joint (pectineus, iliacus, sartorius)
- extend the knee (quadriceps femoris: rectus femoris, vastus lateralis, vastus medialis and vastus intermedius)
Sensory functions: Supplies cutaneous branches to the:
- anteromedial thigh (anterior cutaneous branches of the femoral nerve)
- medial side of the leg and foot (saphenous nerve).
Derived from the anterior rami of nerve roots L2, L3 and L4
Where does the femoral nerve divide and what are the branches?
4cm below the inguinal ligament
Anterior division of the femoral nerve
- Anterior cutaneous branches
- Branch to sartorius
- Branch to pectineus
Posterior division of the femoral nerve
- Saphenous nerve (travels through the adductor canal)
- Branches to quadriceps femoris
What are the features of a prolapsed disc and how do you manage it?
Features
- leg pain usually worse than back
- pain often worse when sitting
- similar to that of other musculoskeletal lower back pain: analgesia, physiotherapy, exercises
- if symptoms persist then referral for consideration of MRI is appropriate