What is the initial approach for a 28-year-old presenting with bilateral foot pain?

Initial Approach to Bilateral Foot Pain in a 28-Year-Old

Begin with plain radiographs (three-view: AP, oblique, lateral) as your initial imaging study, while simultaneously conducting a focused history and physical examination to identify mechanical causes, systemic disease, or neuropathic conditions. 1, 2

Critical History Elements

Obtain these specific details:

• Pain characteristics: Location (plantar heel, midfoot, forefoot), timing (first steps in morning suggests plantar fasciitis, night pain suggests inflammatory/systemic disease), and onset (acute trauma vs. insidious) 2, 3, 4
• Activity patterns: Recent increase in walking/running activity (suggests stress fracture), prolonged standing, or sedentary lifestyle 3, 4
• Footwear history: Type of shoes worn, recent changes, pain relief when barefoot vs. in shoes 2
• Systemic symptoms: Fever, weight loss, morning stiffness >30 minutes (suggests inflammatory arthritis), skin changes, or numbness/tingling 1
• Medical history: Diabetes (critical for neuropathy/infection risk), obesity, inflammatory conditions, previous foot trauma or surgery 1, 4
• Risk factors: Smoking, alcohol use, vitamin B12 deficiency, neurotoxic medications 1

Essential Physical Examination Components

Perform these specific assessments:

Neurological Examination

• 10-g monofilament test on both feet (dorsal hallux, moving proximally) to assess for loss of protective sensation 1
• 128-Hz tuning fork for vibration threshold 1
• Pinprick sensation and ankle reflexes 1
• Note: Absent monofilament sensation indicates loss of protective sensation; at least two normal tests rule it out 1

Vascular Assessment

• Palpate dorsalis pedis and posterior tibial pulses bilaterally 1
• Assess for claudication symptoms, leg fatigue, or decreased walking speed 1
• Inspect for skin changes suggesting ischemia 1

Musculoskeletal Examination

• Point tenderness mapping: Systematically palpate medial plantar calcaneus (plantar fasciitis), Achilles insertion, lateral malleolus, metatarsal heads, and midfoot structures 2, 4
• Calcaneal squeeze test (medial-to-lateral compression) for stress fracture 2
• Passive ankle/first toe dorsiflexion to elicit plantar fascia pain 4
• Inspect for deformities (hammertoes, bunions, flattened arch), calluses, erythema, or swelling 1, 2
• Assess gait pattern and weight-bearing ability 5

Skin and Soft Tissue

• Examine for ulcers, wounds, or signs of infection (erythema, warmth, purulent discharge) 1
• Check for skin integrity and any penetrating trauma 1

Initial Imaging

Standard three-view radiographs (AP, oblique, lateral) of both feet are the first-line imaging study with 80-100% sensitivity for most bony pathology including fractures and tarsal coalitions 1, 5, 2

Obtain weight-bearing views when possible, as they increase detection of subtle malalignment and stress-related pathology 1, 2

Differential Diagnosis Framework by Age and Bilaterality

In a 28-year-old with bilateral foot pain, prioritize:

Mechanical Causes (Most Common)

• Plantar fasciitis: Pain with first steps in morning, medial plantar calcaneal tenderness 2, 3, 4
• Stress fractures: History of increased activity, negative initial radiographs common 2
• Metatarsalgia: Forefoot pain, often activity-related 2

Systemic/Inflammatory Causes

• Inflammatory arthritis (rheumatoid, psoriatic, reactive): Morning stiffness, bilateral symmetric involvement 2
• Seronegative spondyloarthropathies: Heel pain, enthesitis 2

Neurologic Causes

• Peripheral neuropathy: Consider if sensory changes present; evaluate for diabetes, B12 deficiency, alcohol abuse, neurotoxic medications 1, 6
• Tarsal tunnel syndrome: Burning pain, positive Tinel's sign 2

Laboratory Testing

Order if systemic disease suspected:

• Complete blood count, inflammatory markers (ESR, CRP) 1
• Fasting glucose or HbA1c if neuropathy suspected 1
• Vitamin B12 level if neuropathy present 1
• Rheumatologic workup if inflammatory arthritis suspected 2

Advanced Imaging Indications

Order MRI foot without contrast if:

• Radiographs negative but high clinical suspicion for stress fracture 2
• Suspected soft tissue pathology (plantar fascia tear, tendinopathy) 2
• Suspected neuropathy requiring visualization of denervation changes 2

Consider ultrasound as equivalent alternative for:

• Plantar fasciitis/fascia tear 2
• Morton's neuroma or intermetatarsal bursitis 5

Critical Pitfalls to Avoid

• Reexamine 3-5 days post-initial visit if acute onset, as excessive swelling can limit initial examination 2
• Do not miss small avulsion fractures on radiographs; perform systematic review 5, 2
• Stress fractures often have negative initial radiographs; maintain high suspicion with appropriate history 2
• Do not apply Ottawa rules if diabetes/neuropathy present, as pain perception is diminished 1
• Bilateral presentation in young patient warrants systemic disease consideration, not just mechanical causes 2, 6