Differential Diagnosis for Pain at Old Fracture Site
Single Most Likely Diagnosis
- Nonunion or Malunion of Fracture: This is the most likely diagnosis as it can cause chronic pain and discomfort, especially with activities that increase blood flow or put stress on the affected area, such as showering. The warm water from the shower may increase blood flow to the area, exacerbating the pain.
Other Likely Diagnoses
- Hardware Failure (e.g., loose screws or plates): If the patient has had internal fixation, hardware failure can cause pain at the fracture site. Showering may not directly cause the pain, but increased activity or movement during showering could exacerbate it.
- Osteoarthritis: Especially if the fracture involved a joint, osteoarthritis could develop over time, leading to pain in the affected area. The pain might be more noticeable during activities like showering due to increased movement or weight-bearing.
- Stress Fracture: Although less common at an old fracture site, a new stress fracture could occur, especially if the patient has resumed activity without proper rehabilitation or has underlying conditions like osteoporosis.
Do Not Miss Diagnoses
- Osteomyelitis (Bone Infection): This is a critical diagnosis not to miss, as it can lead to severe consequences if left untreated. While less common, an old fracture site could potentially become infected, leading to chronic pain. Showering might increase blood flow, potentially exacerbating the pain, but this diagnosis requires immediate medical attention.
- Bone Tumor: Although rare, a bone tumor (benign or malignant) could develop at the site of an old fracture. This would be a critical diagnosis to consider, especially if the pain is persistent, worsening, or accompanied by other systemic symptoms.
Rare Diagnoses
- Complex Regional Pain Syndrome (CRPS): This is a rare condition characterized by chronic pain, inflammation, and hypersensitivity following an injury, such as a fracture. While it's less common, CRPS could cause significant pain at the fracture site, potentially worsened by activities like showering.
- Avascular Necrosis: If the fracture affected the blood supply to the bone, avascular necrosis could occur, leading to bone death and chronic pain. This condition is more common in certain types of fractures (e.g., hip fractures) but could be considered in the differential diagnosis for pain at an old fracture site.