What is the recommended physical exam for a patient with diabetes presenting with plantar pain?

Physical Examination for Diabetic Patients with Plantar Pain

The recommended physical examination for a patient with diabetes presenting with plantar pain should include a comprehensive foot assessment with inspection of the skin, assessment of foot deformities, neurological assessment (10-g monofilament testing with at least one other assessment such as pinprick, temperature, or vibration), and vascular assessment including pulses in the legs and feet. 1

Comprehensive Foot Examination Components

Skin and Structural Assessment

• Inspect the skin for integrity, color, moisture, temperature, and presence of any lesions, ulcerations, calluses, or wounds 1, 2
• Assess for foot deformities such as bunions, hammertoes, and prominent metatarsal heads that increase plantar foot pressures and risk for ulcerations 1, 2
• Look for erythema, warmth, or calluses which may indicate increased plantar pressures 1
• Evaluate for signs of Charcot foot, which requires special consideration and thorough workup 1

Neurological Assessment

• Perform 10-g Semmes-Weinstein monofilament test as the primary test for assessing loss of protective sensation (LOPS) 1, 3
• Include at least one additional neurological test 1:
  • Vibration perception using a 128-Hz tuning fork 1, 3
  • Pinprick sensation 1
  • Temperature sensation 1
  • Ankle reflexes 2

Vascular Assessment

• Palpate pedal pulses (dorsalis pedis and posterior tibial) 1, 2
• Assess for capillary refill time, rubor on dependency, pallor on elevation, and venous filling time 2
• Note any signs of peripheral arterial disease (PAD), including decreased walking speed, leg fatigue, or claudication 1, 3
• Consider ankle-brachial index (ABI) testing if symptoms or signs of PAD are present 1, 3

Special Considerations for Plantar Pain

• For patients with plantar pain, pay particular attention to the plantar fascia and heel region 4
• Evaluate for tenderness at the medial calcaneal tubercle (common in plantar fasciitis) 4
• Assess for pain with passive dorsiflexion of the toes (windlass test) 4
• Examine footwear for proper fit and adequate cushioning 1, 3

Laboratory and Imaging Considerations

• Consider inflammatory serum biomarkers such as C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), or procalcitonin (PCT) if infection is suspected but clinical examination is equivocal 1
• Imaging is not recommended for the initial approach to plantar fasciitis but may be considered if the diagnosis remains unclear or if osteomyelitis is suspected 1, 4
• If osteomyelitis is suspected, consider a combination of probe-to-bone test, plain X-rays, and inflammatory markers (ESR, CRP, or PCT) 1

Risk Stratification

• Based on the examination findings, classify the patient into a risk category to guide management and follow-up frequency 3
• Patients with a history of foot ulceration or amputation should undergo examination every 1-3 months 3
• All patients with diabetes should undergo a comprehensive foot examination at least annually 1, 3

Evidence Quality and Considerations

The recommendations for physical examination are primarily based on guidelines from the American Diabetes Association 1, 3 and the International Working Group on the Diabetic Foot 1. These guidelines emphasize the importance of a systematic approach to foot examination in diabetic patients.

Research has shown that the 10-g monofilament examination and vibration testing have the best reproducibility and validity for detecting peripheral neuropathy 5, 6, 7. These tests are both sensitive and specific for identifying patients at risk for foot complications.

For patients specifically presenting with plantar pain, the physical examination should focus on distinguishing between common causes such as plantar fasciitis, which is particularly common in diabetic patients, and more serious conditions like infections or Charcot arthropathy 4.