Diabetic foot Flashcards
What is the underlying disorder that drives the development of diabetic foot problems?
- Neuropathy
- Obliterative atheroscleorosis
- Mixture of both
Which type of diabetes is more at risk of developing diabetic foot problems?
Type 2
How does neuropathy occur in diabetes?
Microangiopathy which leads to peripheral neuropathies causing motor, sensory and autonomic nerve problems.
How does motor nerve damage contribute to diabetic foot?
Supply of motor nerves to the small muscles of the foot becomes unmodified, leading to traction in the calf which distorts te morphology and weight-bearing characteristics of the foot.
How does sensory nerve damage contribute to the development of diabetic foot?
Sensory neuropathy lessens pain sensation and hence awareness of potential injury from ill-fitting footwear and foreign bodies in shoes
How does autonomic nerve damage contribute to the development of diabetic foot?
Damaged autonomic nerves disrupts vascular control and causes loss of sweating (anhidrosis)
What are the major factors which lead to the development of diabetic foot?
- Neuropathy
- Arteriovenous communications
- Arteriole narrowing
- Impaired intermediary tissue metabolism
- Obliterative atherosclerosis
How does arteriole narrowing contribute to the development of diabetic foot?
Restriction of capillary perfusion
How does impaired intermediary tissue metabolism and gluose-rich tissue contribute tot he development of diabetic foor complicaitons?
Both factors favour bacterial growth and spreading of infection
How does obliterative atherosclerosis seen in diabetics contribute to the development of diabetic foot problems?
Leads to arterial insufficiency
Why does damaged tissue heal poorly in people with diabetes?
Arteriovenous communications open beneath the skin, thus diverting nutrients away from the site of damage
When examining a diabetic foot, what is important to establish?
Whether the problems are due to ischaemia or peripheral neuropathy
- Ischaemia - critical toes +/- absent pedal pulses
- Neuropathy - injury/infection over pressure points
What is important to remember when trying to distinguish between ischaemia and peripheral neuropathy in a diabetic foot?
Both can be present - need to be aware of this as an acutely ischaemic or critical foot can be warm and red due to autonomic dysregulation
What are signs of neuropathy?
- Decreased sensation in stocking distribution
- Absent ankle jerk
- Decreased vibration sensation
- Decreased proprioception
- Neuropathic deformity - pes cavus, claw toes, loss of transverse arch
What are signs of ischaemia in a diabetic foot?
- Absent pulses
- Decreased temperature
- Trophic changes
- Evidence of necrosis
