Following brain injury, pain symptoms may be associated with a range of medical 
conditions, including the following:
- Inflammatory complications following brain injury or associated treatments:
- Pressure related skin irritation or skin breakdown or skin infections.
- Other infections (e.g. urinary tract or catheter related infection; respiratory tract infections).
- Peptic ulceration due to associated stress response.
- Visceral pain i.e. intra-thoracic or intra-abdominal:
- Associated intra-abdominal or intra-thoracic injury.
- Visceral muscle dysfunction arising from immobility or autonomic dysfunction (e.g urine retention; detrusor instability or constipation leading to faecal loading or bowel obstruction).
- Coincidental unrelated causes (e.g. myocardial infarction).
- Pre-existing or unrelated pain patterns (e.g. pre-existing arthritis).