Whiplash is a cervical strain injury that results from the forceful and rapid back and forth movement of the neck. As explained by the Mayo Clinic, the most common cause of whiplash is a rear-end auto accident.
The Mechanics of Whiplash
The average adult head weighs 10 to 11 pounds. In a rear-end collision, the hit car suddenly moves forward. The occupant’s body initially remains stationary and is pressed into the seat as it is moving forward. But the unrestrained head does not, causing the head to whip back and down, stretching the muscles and the ligaments of the neck. After hitting head restraint, the head then snaps forward. The occupant’s body’s forward motion is then stopped by the shoulder seatbelt, but the head keeps moving forward, again stretching the muscles and ligaments of the neck. All of this occurs within less than a second and so quickly the occupant may not even notice the initial backward motion. The Harvard Medical School notes that even a relatively low speed rear-end collision between a car traveling 10 mph and a stationary car can briefly put 9 Gs of force on a person’s neck. Whiplash results when the muscles and ligaments in the neck stretch and tear trying to hold the vertebrae together against this whipping motion.
Whiplash symptoms usually appear within 24 hours of a collision, but may not appear for a few days or weeks. Symptoms of whiplash include:
- neck pain and stiffness
- loss of range of motion in the neck
- headaches, usually starting at the base of the skull
- pain in the shoulder or between the shoulder blades
- pain, tingling or numbness in the arm and/or hand
- difficulty concentrating or remembering
The duration of whiplash symptoms can vary greatly. Many individuals will recover within 6 weeks to 3 months. But if the whiplash is severe, or the injured person is older, has preexisting problems with neck pain, arthritis, or headaches, or has had whiplash before, the symptoms can last much longer. Whiplash becomes chronic when it lasts six months or longer.