Differential Diagnosis for Sharp Pain under Old Scars

Single Most Likely Diagnosis

• Neuroma formation: This is a common cause of sharp pain under old scars. Neuromas are benign growths of nerve tissue that can develop at the site of a scar, leading to pain, numbness, or tingling.

Other Likely Diagnoses

• Scar tissue pain: Sharp pain can occur due to the formation of scar tissue under the skin, which can be tender and painful.
• Adhesions: Adhesions are bands of fibrous tissue that can form between organs or between an organ and the abdominal wall, leading to sharp pain under old scars.
• Keloid or hypertrophic scarring: These types of scars can be painful and may cause sharp pain, especially if they are large or in a sensitive area.

Do Not Miss Diagnoses

• Infection or abscess: Although less likely, an infection or abscess under an old scar can cause sharp pain and would require prompt medical attention to prevent serious complications.
• Malignant transformation: In rare cases, a scar can be a site for malignant transformation, such as the development of a scar-related squamous cell carcinoma or basal cell carcinoma.
• Hernia: An incisional hernia can occur through an old scar, leading to sharp pain and potentially serious complications if not treated.

Rare Diagnoses

• Epileptic seizure focus: In some cases, a scar can be a focus for epileptic seizures, especially if the scar is located near the brain.
• Complex regional pain syndrome (CRPS): This is a rare condition characterized by chronic pain, inflammation, and sensitivity in one limb after an injury or trauma, which can include sharp pain under old scars.
• Neurofibroma: A neurofibroma is a rare type of tumor that can develop under an old scar, leading to sharp pain and other symptoms.