Recurring Painful Plantar Lesion: Diagnosis and Management
For a painful plantar lesion recurring over 10 years, the most likely diagnosis is a plantar wart (verruca plantaris) or plantar fibromatosis, and initial management should begin with plain radiographs to rule out underlying bone pathology, followed by topical keratolytic therapy for warts or surgical consultation for fibromatosis if conservative measures fail.
Initial Diagnostic Approach
Start with plain foot radiographs as the first imaging study to evaluate for any underlying osseous abnormalities, stress fractures, or bone lesions that could explain the chronic recurring nature 1. Radiography is the appropriate initial imaging modality for chronic foot pain of unknown etiology and can identify structural problems beneath the lesion 1.
Key Clinical Features to Assess
- Location and characteristics: Plantar lesions beneath osseous prominences (especially metatarsal heads) suggest hyperkeratotic disorders or warts 2
- Pain pattern: Pain with direct pressure suggests a wart or callus, while pain radiating or burning suggests nerve involvement 3
- Lesion appearance: Hyperkeratotic nodular lesions may indicate verruca plantaris, while firm nodules in the plantar fascia suggest fibromatosis 4, 5
- History of trauma or increased activity: Important to rule out stress fracture or bone marrow lesions 6
Most Likely Diagnoses for 10-Year Recurring Plantar Lesion
1. Plantar Wart (Verruca Plantaris)
This is the most common recurring painful plantar lesion. Warts are hyperkeratotic lesions that develop beneath osseous prominences and cause substantial disability during gait 2.
Treatment algorithm:
- First-line: Topical salicylic acid 6-30% for removal of excessive keratin 7, 8
- Second-line: Combination therapy with cantharidin 1%/podophyllum resin 5%/salicylic acid 30% 8
- Refractory cases: Referral to podiatric surgeon if no improvement after 6-8 weeks 9, 3
2. Plantar Fibromatosis
This benign hyperproliferative lesion of the plantar fascia has a 60% overall recurrence rate after surgery 4. It presents as firm nodules in the plantar fascia and can cause chronic pain 4, 5.
Treatment algorithm:
- Conservative first: Only operate when highly symptomatic and conservative measures fail 4
- Surgical options if needed: Total plantar fasciectomy has the lowest recurrence rate (25%) compared to local excision (100% recurrence) 4
- Consider adjunctive radiotherapy: May reduce recurrence rates when combined with surgery 4
3. Bone Marrow Lesion with Chronic Fasciitis
If the lesion is associated with persistent plantar fascia pain and previous treatments have failed, MRI should be obtained to identify bone marrow lesions at the fascia origin 6.
Advanced Imaging When Radiographs Are Normal
If plain radiographs are negative but pain persists, proceed with MRI without contrast 1. MRI has excellent sensitivity for:
- Soft tissue pathology including fibromatosis 10
- Bone marrow lesions 6
- Nerve compression if tarsal tunnel syndrome is suspected 10
Conservative Management Protocol
Initial 6-8 Week Trial
- Activity modification: Reduce weight-bearing activities that reproduce symptoms 9, 10
- NSAIDs: Oral ibuprofen or naproxen for pain and inflammation 9, 10
- Proper footwear: Shoes with adequate cushioning and arch support to redistribute plantar pressure 1, 9
- Orthotic devices: Custom or over-the-counter arch supports to reduce pressure on the lesion 9, 10
- Topical keratolytics: If hyperkeratotic lesion, apply salicylic acid 6% 7
Common Pitfall to Avoid
Do not inject corticosteroids near the plantar fascia or Achilles tendon due to risk of rupture 9, 3, 10. If injection is considered, it should only be in the tarsal tunnel area and performed by an experienced clinician 10.
When to Refer to Podiatric Surgery
Refer after 6-8 weeks of appropriate conservative treatment without improvement 9, 3, 10. Surgical consultation is also indicated for:
- Suspected plantar fibromatosis requiring excision 4
- Bone marrow lesions identified on MRI that may benefit from subchondroplasty 6
- Recurrent warts unresponsive to topical therapy 7
Red Flags Requiring Immediate Evaluation
- Constant pain at rest: May indicate infection, tumor, or severe nerve compression 9
- Progressive numbness or burning: Suggests tarsal tunnel syndrome or other neurologic pathology 3, 10
- Rapid swelling or erythema: Could indicate infection requiring urgent assessment 1
- Bilateral symptoms with joint pain elsewhere: Consider inflammatory arthropathy 3
For diabetic patients specifically, any plantar lesion requires comprehensive foot evaluation including monofilament testing, vascular assessment, and aggressive wound care to prevent ulceration and infection 1.