What is the treatment for acute pain in the first metatarsophalangeal joint in a patient with diabetes mellitus (DM) and peripheral artery disease (PAD)?

Treatment of Acute Pain in the First Metatarsophalangeal Joint in Patients with Diabetes Mellitus and Peripheral Artery Disease

For acute pain in the first metatarsophalangeal joint in patients with diabetes mellitus (DM) and peripheral artery disease (PAD), prompt evaluation for infection and ischemia is essential, with immediate referral to a multidisciplinary diabetic foot care team to reduce the risk of amputation.

Initial Assessment and Diagnosis

Vascular Assessment

• Evaluate for PAD severity by:
  • Palpating foot pulses
  • Measuring ankle-brachial index (ABI) - values <0.9 indicate PAD, <0.7 indicate significant PAD that will impair healing 1
  • Consider toe pressure measurements (target ≥30 mmHg) or transcutaneous oxygen pressure (TcPO2 ≥25 mmHg) 2

Infection Assessment

• Look for signs of infection:
  • Local pain/tenderness
  • Periwound erythema, edema, induration
  • Discharge (especially purulent)
  • Foul odor
  • Visible bone or probe-to-bone test
  • Systemic inflammatory response signs 2

Treatment Algorithm

1. Emergency Management

• If signs of infection are present with PAD: This combination creates particularly high risk for amputation and requires emergency treatment 2, 1
  • Prompt surgical drainage if deep soft tissue infection
  • Appropriate antibiotic therapy based on culture results
  • Urgent vascular imaging and expeditious revascularization

2. Pain Management

• First-line analgesics:
  • Non-weight bearing on affected foot
  • Acetaminophen for mild pain
  • NSAIDs if no contraindications (use caution with renal impairment)
  • For moderate-severe pain: consider short-term opioid analgesics

3. Revascularization Assessment

• If perfusion is inadequate (ABI <0.5 or ankle pressure <50 mmHg), consider revascularization 1
• The aim is to restore direct flow to at least one foot artery, preferably the one supplying the affected area 2
• Both endovascular techniques and bypass surgery should be available 2
• Decision between techniques should be made by a multidisciplinary team based on:
  • Morphological distribution of PAD
  • Availability of autogenous vein
  • Patient comorbidities
  • Local expertise 2

4. Offloading

• Use non-removable knee-high offloading devices (total contact cast) for plantar ulcers 1
• Appropriate footwear modifications for non-plantar ulcers

5. Wound Care (if ulceration present)

• Regular debridement of necrotic tissue and surrounding callus
• Appropriate dressings to control exudate and maintain moist environment
• Consider negative pressure wound therapy for post-operative wounds 1

Concurrent Medical Management

Cardiovascular Risk Reduction

• Antiplatelet therapy:
  • Aspirin (75-325 mg daily) or clopidogrel (75 mg daily) 2
• Statin therapy:
  • Target LDL-C <70 mg/dL for patients at very high risk 2
• Antihypertensive therapy:
  • Target BP <130/80 mmHg for patients with diabetes 2
  • ACE inhibitors may be beneficial 2
  • Beta-blockers are not contraindicated in PAD 2

Diabetes Management

• Target HbA1c <7% to reduce microvascular complications 2
• Proper foot care education 2

Smoking Cessation

• All patients who smoke should be strongly advised to quit and offered pharmacotherapy (varenicline, bupropion, nicotine replacement) 2

Follow-up Care

• Regular evaluation by multidisciplinary team
• Reassessment of perfusion if wound healing is poor
• Long-term measures to prevent recurrence 1

Important Caveats

• Amputation should only be considered after revascularization attempts have failed 1
• Patients with both PAD and diabetes have a 50% 5-year mortality rate 3
• The presence of infection with PAD significantly increases amputation risk (nearly 3-fold) 2
• Antiplatelet therapy alone will not adequately address perfusion issues needed for wound healing 1

Remember that early diagnosis and treatment are crucial to reduce the risk of amputation and mortality in this high-risk population.