Subdural Hematoma: This is the most likely diagnosis due to the patient's age and the mechanism of injury. Elderly patients are more prone to subdural hematomas due to the increased space between the brain and the skull, which allows for more movement of the brain and subsequent bleeding from bridging veins.

Concussion: A concussion is a common injury after a fall, especially in the elderly. It can present with symptoms such as confusion, disorientation, and memory loss.
Cerebral Contusion: A cerebral contusion can occur when the brain is directly injured by the skull, leading to bruising and swelling of the brain tissue.
Skull Fracture: A skull fracture is possible, especially if the patient fell from a significant height or hit a hard surface.

Epidural Hematoma: Although less common than subdural hematoma, an epidural hematoma is a medical emergency that requires prompt diagnosis and treatment. It is characterized by a collection of blood between the skull and the dura mater.
Subarachnoid Hemorrhage: This is a life-threatening condition that occurs when there is bleeding into the space surrounding the brain. It can be caused by trauma and requires immediate medical attention.
Cervical Spine Injury: The cervical spine is vulnerable to injury during a fall, and missing a cervical spine fracture or dislocation can have devastating consequences.

Traumatic Arteriovenous Fistula: This is a rare condition where a connection forms between an artery and a vein due to trauma, leading to abnormal blood flow.
Traumatic Pseudoaneurysm: A pseudoaneurysm is a rare complication of head trauma, where a blood vessel is injured, leading to the formation of a false aneurysm.
Diffuse Axonal Injury: This is a rare but severe type of brain injury that occurs when the brain is severely shaken or rotated, causing damage to the axons.