Brachial Plexus Injury: This is a common injury in bike accidents, especially if the rider falls on their shoulder or outstretches their arm to break their fall. The brachial plexus is a network of nerves that originates in the spinal cord and controls muscle movements and sensation in the shoulder, elbow, wrist, and hand. Injury to this area can cause neurologic pain, numbness, and weakness in the shoulder and arm.

Rotator Cuff Injury: The rotator cuff is a group of muscles and tendons that surround the shoulder joint, keeping the head of the humerus (upper arm bone) firmly within the shallow socket of the shoulder. A bike accident can cause a fall onto the shoulder, leading to rotator cuff strain or tear, which may present with neurologic pain due to associated nerve irritation.
Clavicle Fracture: A fracture of the clavicle (collarbone) is common in bike accidents, especially if the rider falls onto their shoulder or outstretches their arm. While primarily a bony injury, a clavicle fracture can cause neurologic pain if the fracture fragments irritate nearby nerves.
Thoracic Outlet Syndrome: This condition involves compression, injury, or irritation of the nerves and/or blood vessels (arteries and veins) in the thoracic outlet area, which lies between your collarbone (clavicle) and first rib. A bike accident could exacerbate or precipitate this condition, leading to neurologic pain in the shoulder.

Spinal Cord Injury: Although less common, a spinal cord injury is a potentially devastating consequence of a bike accident. Any neurologic symptoms, including pain, numbness, or weakness in the shoulder or anywhere else, could indicate a spinal cord injury, which requires immediate medical attention.
Vascular Injury: Injury to the blood vessels in the shoulder or chest area can occur in severe bike accidents. Vascular injuries, such as an axillary artery injury, can present with neurologic pain due to ischemia (lack of blood flow) and must be identified and treated promptly to prevent serious complications.

Complex Regional Pain Syndrome (CRPS): This is a rare condition characterized by persistent burning pain and hypersensitivity after an injury. While not immediately life-threatening, CRPS can significantly affect quality of life and should be considered in cases of persistent, unexplained neurologic pain following a bike accident.
Neurogenic Thoracic Outlet Syndrome due to Rare Anatomical Variations: Some individuals may have anatomical variations that predispose them to neurogenic thoracic outlet syndrome, where the nerves are compressed. This could be exacerbated by a bike accident and is a rare but important consideration in the differential diagnosis.