Registered Nurses' Association of Ontario

Components of Peripheral Neuropathy, Associated Pathophysiological Involvement, Assessment Considerations and Clinical Indications

COMPONENT ASSOCIATED PATHOPHYSIOLOGICAL INVOLVEMENT ASSESSMENT CONSIDERATIONS CLINICAL INDICATIONS
Sensory
  • Myelin sheath is disrupted  by hyperglycemia
  • Disruption leads to the segmental demyelinization process accompanied by a slowing of motor nerve conduction and an impairment of sensory perception
  • Pressure perception testing using a 10-gr* (5.07 Semmes-Weinstein) monofilament, is recommended
  • Vibration perception (using a tuning fork)
  • Tactile sensation (using a cotton  ball)
  • Loss of protective sensation
  • Sensory ataxia
  • Falls (15-fold increase compared to those without diabetes)
  • Callus
Autonomic

Sympathetic Denervation

  • Loss of vasomotor control
  • Peripheral blood flow
  • Arteriovenous shunting
  • Bone blood flow hyperemia
  • Glycosylation of collagen

Inspect for:

  • Dry scaly skin caused by lack of hydration
  • Inspect between the toes especially between  the fourth and fifth toes for fissures
  • Maceration
  • Loss of hair growth and thickened toenails
  • Anhydrosis
  • Callus
  • Fissure cracks
  • Onychomycosis (fungal  nails)
  • Peripheral edema
  • Waxy skin (sign of altered joint mobility)
Motor
  • Non-enzymatic glycosylation
  • Atrophy of intrinsic muscles of the foot (toe plantar  flexors)
  • Subluxation  of metatarsophalang at joints

Inspect for:

  • Gait assessment
  • Range of motion
  • Muscle testing
  • Absent deep tendon reflexes
  • Callus
  • Claw toes
  • Hammer toes
  • Charcot arthropathy
  • Muscle weakness
  • Ankle equines
  • Pes cavus
  • Pes planus
  • Contracture  of Achilles Tendon

*Using 10 or 4 points on the foot is acceptable.

Chronic Disease
Assessment and Management of Foot Ulcers for People with Diabetes - Second Edition
Point of Care Resources