What is the best course of treatment for an older adult patient with severe foot and great toe pain, no fracture on X-ray, and a history of gout or diabetes?

Severe Foot and Great Toe Pain Without Fracture

In an older adult with severe foot and great toe pain, negative X-ray, and history of gout or diabetes, immediately obtain MRI of the foot to rule out occult fracture, osteomyelitis, or soft tissue pathology, while simultaneously initiating treatment based on the most likely diagnosis from clinical examination. 1

Immediate Diagnostic Approach

Clinical Examination Priorities

For diabetic patients, urgently assess for infection signs including erythema, warmth, purulent drainage, fluctuance, or systemic symptoms (fever, tachycardia), as these indicate potentially limb-threatening infection requiring surgical consultation within 2-4 hours. 1, 2

• Examine for crepitus or tissue gas, which indicates necrotizing fasciitis requiring emergency surgery. 2
• Perform probe-to-bone test at any wound base—if bone is palpable with a sterile probe, osteomyelitis is highly likely. 2
• Palpate pedal pulses and assess for critical limb ischemia; absent or diminished pulses require urgent vascular surgery consultation within 24 hours. 1, 2

For gout presentation, look for acute onset (hours to days), severe pain disproportionate to examination, erythema, warmth, and exquisite tenderness over the first metatarsophalangeal joint or other joints. 1

Advanced Imaging Selection

MRI foot without IV contrast is the most appropriate next imaging study after negative radiographs for persistent foot pain, with 93% sensitivity for detecting occult pathology including fractures, osteomyelitis, Morton's neuroma, and soft tissue injuries. 1, 3

• MRI demonstrates occult fractures in the calcaneus, metatarsals, navicular, cuboid, and cuneiform bones that are radiographically invisible. 1
• For suspected osteomyelitis in diabetic patients, MRI shows bone marrow edema and can differentiate infection from Charcot arthropathy. 1
• Ultrasound is an acceptable alternative for plantar fasciitis, Morton's neuroma, or sesamoiditis when MRI is unavailable, offering dynamic assessment and direct clinical correlation. 1

Management Based on Diagnosis

If Diabetic Foot Infection is Present

Obtain urgent surgical consultation immediately for any diabetic patient with moderate to severe infection, deep abscess, extensive gangrene, necrotizing infection, or compartment syndrome. 1, 2

• Initiate broad-spectrum parenteral antibiotics with piperacillin-tazobactam as the preferred empiric regimen for severe infections, or vancomycin plus ceftazidime when MRSA is suspected. 2
• Early surgery within 24-48 hours combined with antibiotics results in lower major amputation rates and higher wound healing rates compared to delayed intervention. 1, 2
• Obtain tissue specimens for culture after debridement during surgery (not swabs) to guide antibiotic therapy. 2
• Continue antibiotics for 2-4 weeks depending on adequacy of debridement, but stop when infection resolves, not when the wound heals. 2

If Gout is Suspected

Initiate colchicine 1.2 mg (two 0.6 mg tablets) immediately, followed by 0.6 mg one hour later for acute gout flare treatment. 4

• For patients with severe renal impairment (CrCl <30 mL/min) or on dialysis, reduce to a single 0.6 mg dose and do not repeat more than once every two weeks. 4
• For patients with severe hepatic impairment, use the standard dose but do not repeat the treatment course more than once every two weeks. 4
• Avoid NSAIDs in older adults with renal impairment or cardiovascular disease. 1
• Consider local corticosteroid injection for insertional Achilles tendonitis or bursitis, but never inject near the Achilles tendon itself. 1

If Occult Fracture is Found

Great toe fractures require a short leg walking boot or cast with toe plate for 2-3 weeks, followed by a rigid-sole shoe for an additional 3-4 weeks, due to the critical role of the great toe in weight-bearing. 5, 6

• Metatarsal shaft fractures are managed with a short leg walking boot or hard-soled shoe for 3-6 weeks with progressive weight-bearing as tolerated. 7, 5
• Fifth metatarsal base fractures require specific management: tuberosity avulsions can use a compressive dressing then walking boot for 2 weeks, while Jones fractures (metaphyseal-diaphyseal junction) require 6-8 weeks in a non-weight-bearing cast due to high nonunion risk. 7, 5
• Sesamoid fractures of the great toe are treated with a short leg walking boot for 4-6 weeks; consider surgical referral if conservative treatment fails after 3 months. 6

If Soft Tissue Pathology is Identified

For plantar fasciitis, initiate stretching exercises, heel lifts or orthoses, NSAIDs, and activity modification; consider immobilization cast if no improvement after 2-3 months. 1

For Morton's neuroma (intermetatarsal pain), begin with NSAIDs and orthotic devices; if conservative measures fail, proceed to corticosteroid injection with triamcinolone acetonide placed beside (not into) the neuroma. 3

For sesamoiditis, use a short leg walking boot, metatarsal pad, and NSAIDs for 4-6 weeks. 1

Critical Pitfalls to Avoid

• Never delay surgical consultation in diabetic patients with signs of deep infection, fluctuance, or systemic symptoms—prolonged antibiotic therapy alone increases major amputation risk. 1, 2
• Never continue antibiotics for the entire duration the wound remains open; stop when infection resolves clinically. 2
• Never assume normal radiographs exclude fracture in patients with persistent severe pain—up to 24 occult fractures were found on ultrasound in 268 patients with negative X-rays. 1
• Never inject corticosteroids directly into or near the Achilles tendon due to rupture risk. 1
• Never treat great toe fractures casually—they require more aggressive immobilization than lesser toe fractures due to their weight-bearing function. 5, 6

Diabetic-Specific Preventive Measures

All diabetic patients require comprehensive foot care education including daily inspection, water temperature below 37°C for washing, never walking barefoot, and immediate reporting of any blisters or wounds. 1

• Ensure appropriate footwear with 1-2 cm longer internal length than the foot and width equal to the metatarsophalangeal joint width, evaluated in standing position at end of day. 1
• Refer for regular podiatric care to manage calluses, nail pathology, and foot deformities before ulceration develops. 1