The non-healing skin ulcer
Separating vascular, inflammatory, malignant, neuropathic and infectious ulcers.
Updated: 2026-09-13
Written for clinicians and medical students
This section is a teaching reference for doctors, residents and medical students. It is not patient guidance and not a substitute for clinical examination, and it must not be used for self treatment.
Pattern and causes
| Pattern | Consider |
|---|---|
| Gaiter area, shallow, oedema and pigmentation | Venous ulcer |
| Distal, punched-out, cool foot, reduced pulses | Arterial ulcer |
| Pressure point with sensory loss | Neuropathic or pressure ulcer |
| Rapidly progressive, very painful, undermined violaceous edge | Pyoderma gangrenosum |
| Rolled, everted, indurated or exuberant edge | Skin cancer or malignant transformation |
| Travel, immunosuppression, unusual drainage or exposure | Deep fungal, mycobacterial or parasitic infection |
Safe work-up
- Assess perfusion before compression. Record pulses and ankle-brachial pressure index when appropriate, recognising that calcified vessels can make results unreliable [1].
- Biopsy an atypical or non-healing ulcer from the active edge and include sufficient depth. Send separate tissue for culture when infection is considered [2].
- Avoid debridement of suspected pyoderma gangrenosum until specialist review because pathergy can worsen disease [2].