Leg Ulcers Flashcards
What is the definition of an ulcer?
A local defect, or excavation of the surface of an organ or tissue that is produced by sloughing of inflammatory necrotic tissue
What is the definition of an ulcer in relation to the skin?
the loss of an area of epidermis and dermis to produce a defect, even down to fat, muscle, tendons and bone
What is meant by ‘erosion’?
the loss of an area of epidermis
What are the main 4 causes of leg ulcers?
- traumatic
- vascular
- inflammatory
- neuropathic
What % of leg ulcer causes are arterial and venous?
70% are venous
10% are arterial
10% are mixed
What is calcinosis cutis?
calcium deposition in the skin
How is calcinosis cutis usually brought about?
damaged/inflamed skin prometes deposition of calcium in patients with disordered metabolism of calcium and phosphate
What pre-existing condition is present in most patients that contract calcinosis cutis?
hypercalcaemia
What are 2 diseases that are inflammatory causes of leg ulcers?
- pyoderma gangrenosum
2. panniculitis
What is a disease that is a neuropathic cause of leg ulcers?
peripheral neuropathy
What are examples of diseases that are malignant causes of leg ulcers?
SCC, BCC and lymphoma
What are examples of diseases that are vascular causes of leg ulcers?
- vasculitis and CTD
2. occlusive disease
What are examples of iatrogenic causes of leg ulcers?
- pressure sores
2. drugs - hydroxyurea and warfarin
What are examples of diseases that are metabolic causes of leg ulcers?
- diabetes mellitus
2. calcinosis cutis
What are examples of traumatic events that can cause leg ulcers?
usually chemical, thermal, electrical or radiation burns
Which category is mostly affected by venous leg ulcers?
middle aged to elderly women
they affect 1% of the population
What % of venous leg ulcers are recurrent?
70%
What are the 3 main risk factors for venous leg ulcers?
- valvular incompetence
- previous damage to venous system (e.g. DVT, hypertension)
- obesity & immobility
Why does obesity and immobility lead to venous leg ulcers?
Poor muscle contraction leads to venous pooling and hypertension
What is the definition of a chronic venous leg ulcer?
an open lesion between the knee and the ankle joint that remains unhealed for at least 4 weeks and occurs in the presence of venous disease
What lifestyle related factors may contribute to venous leg ulcers?
- sitting or standing for long periods
- obesity
- increasing age and immobility
What factors relating to the legs may be useful to hear in a history when looking at venous leg ulcers?
- history of leg swelling
2. end of day throbbing and aching in calf muscles
What factors relating to the veins may be useful to hear in a history when looking at venous leg ulcers?
- varicose veins
- history of blood clots in deep veins
- previous surgery
- previous fractures or injuries
(3. and 4. can lead to vein damage and immobility)
What other factors may be useful to hear in a history for venous leg ulcers?
- high blood pressure
2. multiple pregnancies as this increases circulating volume
Upon examination, what are the signs of a venous leg ulcer?
superficial, sloughy with ill defined borders
Where is the most common place to develop a venous leg ulcer?
medial gaiter area
How painful are venous leg ulcers?
generally less painful than arterial leg ulcers
When performing an examination of a venous leg ulcer, what other signs should be looked for?
associated signs of chronic venous hypertension
What are the 5 associated signs of chronic venous hypertension?
- venous flare
- lipodermatosclerosis
- varicose veins
- atrophie blanche
- varicose eczema
What is lipodermatosclerosis?
an inflammatory skin condition resulting from underlying venous insufficiency
How does lipodermatosclerosis develop?
- venous hypertension causes an increase in leukocytes in the vein
- leukocytes migrate to surrounding tissue
- leukocytes are activated and attract and release proinflammatory cells and cytokines
- this induces a chronic inflammatory state
What is the final stage in development of lipodermatosclerosis?
What is it commonly misdaignosed as?
Increased collagen production leads to the fibrosis of subcutaneous fat
Commonly misdiagnosed as cellulitis
What are arterial ulcers often associated with?
peripheral vascular disease
What happens in peripheral vascular disease?
- a plaque builds up in the arteries that carry blood to the lower limbs
- the plaque hardens and narrows the arteries
- the flow of blood to the lefs is limited
What is the plaque made up of in peripheral vascular disease?
fat, cholesterol, calcium, fibrous tissue and other substances in the blood
In general, what are the risk factors for arterial ulcers?
anything that causes cardiovascular or peripheral vascular disease
What 4 things should be looked for in the history of someone with an arterial ulcer?
- intermittent claudication
- rest pain or paraesthesia
- pain at ulcer site
- other symptoms of vascular disease
what is paraesthesia?
an abnormal sensation, typically tingling or pricking (‘pins and needles’), caused chiefly by pressure on or damage to peripheral nerves
What is claudication?
a condition in which cramping pain in the leg is induced exercise
It is typically caused by obstruction of the arteries
What signs will be seen in clinical examination of an arterial ulcer?
- punched out painful ulcer
- loss of hair appendages
- dry skin
- cool peripheries
- pale or cyanotic or pre-gangrenous toes
Where are arterial ulcers usually seen?
On the lower leg and foot
What is meant by Buerger’s sign?
What is it used to detect in arterial ulcers?
the angle to which the leg has to be raised before it becomes pale
used to detect position dependent ischaemia
How do arterial ulcers affect pulse?
reduction in proximal and/or peripheral pulses with or without bruit
What are the 5 P’s of PVD?
- pain
- pulseless
- paraesthesia
- painful
- paralysis
What does a neuropathic ulcer look like and where is it usually found?
Found under metatarsal heads/heel
It is painless but warm with pulses
What is a neuropathic ulcer due to?
distal polyneuropathy
What are the causes of neuropathic ulcers?
the main cause is diabetes
other causes are:
- alcohol
- B1/B12 deficiency
- Charcot Marie Tooth disease
What type of ulcer is pyoderma gangrenosum?
it is an inflammatory ulcer
it is one of a number of neutrophilic dermatoses
What 3 conditions is pyoderma gangrenosum associated with?
- inflammatory bowel disease (Crohns, UC)
- rheumatoid arthritis
- monoclonal gammopathy
In what % of cases is the cause for pyoderma gangrenosum identified?
In 50% of cases, the cause is not identified
What does pyoderma gangrenosum look like initially and as it progresses?
It starts as an initial pustule
It rapidly breaks down into a painful rapidly spreading ulcer
What is the appearance of the ulcer base and margins in pyoderma gangrenosum?
The base of the ulcer is dark red/dusky in colour
The margins are overhanging and purple/bluish
Where is pyoderma gangrenosum most commonly found?
Most common on the anterior shin
It is also seen on the abdomen next to stoma sites
What is significant about the appearance of a malignant ulcer?
It has rolled edges
In which 2 ways can a malignant ulcer occur?
it can occur as a primary malignant lesion
it can also occur secondarily to a chronic ulcer
How is a malignant ulcer diagnosed?
through excision and biopsy
What are the indications for a biopsy of a leg ulcer?
- if it is a clinically atypical ulcer
2. to exclude or diagnose a malignancy
Does an ulcer heal by first or second intention?
Why?
it heals by second intention
there is tissue loss and the margins of the wound are not apposed
What are the 5 steps involved in healing of an ulcer by second intention?
- phagocytosis to remove debris
- granulation tissue fills in the defects and repairs specialised tissues lost
- organisation
- epithelial regeneration and early fibrous scar
- scar contraction
What chemicals are involved in controlling healing and repair?
there is a complex interplay of various cytokines
What are the 3 stages involved in management of a leg ulcer?
- treat the underlying cause of the ulcer
- treat the ulcer
- treat any associated infection
What are ankle brachial pressure indices used to measure?
it is a type of doppler that measures the ankle brachial pressure index (ABPI)
What is the ankle brachial pressure index?
the ratio of systolic blood pressure to occlude dorsalis pedis on doppler compared to systolic pressure of the ipsilateral upper arm
Why is an ankle brachial pressure index used?
To assess how much compression can be applied
What does an ABPI value <0.5 suggest?
there is significant arterial disease
What does an ABPI value of 0.5-0.9 suggest?
claudication
What does an ABPI value >1.0 suggest?
non-significant arterial disease
What ABPI values indicate how much compression can be applied?
0.7-0.8 is okay for light compression
> 1.0 is okay for tight compression
Why are patch tests used in CVLU patients?
many have contact dermatitis to many topical preparations or dressings used in leg ulcers
Which types of CVLU patients should be considered for patch testing?
leg ulcer patients with dermatitis/eczema
Why may a bone scan or MRI be needed in a patient with a leg ulcer?
if it is suspected that chronic osteomyelitis is underlying the ulcer
What are the lifestyle related factors involved in the management of leg ulcers?
- stop smoking
- avoid trauma to the legs
- moderate regular exercise
- avoid obesity
- elevate legs
What are the medical factors involved in the management of leg ulcers?
- treat lower limb oedema and prevent chronic venous hypertension
- analgesia
How can healing of a leg ulcer be encouraged?
- correct dressing choice
2. use of topical treatments
What are the 3 techniques to debride necrotic material in a leg ulcer?
Removing slough/dead tissue through:
- chemical debridement
- manual debridement
- surgical debridement
