Whiplash-associated disorders (WAD) refer to a range of symptoms—including neck pain, stiffness, headaches, dizziness, and reduced mobility—that arise from a hyperextension-flexion injury of the cervical spine. This commonly occurs due to sudden acceleration and deceleration forces, most often seen in motor vehicle collisions. Research suggests that up to 50% of the 3 million Americans who develop WAD each year will continue to experience persistent pain and disability for months or even years post-injury. In order to reduce the risk of chronic WAD and its accompanying impact on the individual and society in general, several studies in the last decade have sought to identify why some patients recover and others don’t. It appears one piece to this puzzle may be what happens within the injured muscles.

In a July 2023 study, researchers recruited 97 adults who visited an emergency room following a motor vehicle collision that did not result in hospitalization. The research team monitored the participants for the following year with the aid of magnetic resonance imaging (MRI), functional examinations, and patient outcome questionnaires. The study found that individuals with greater fat infiltration in their neck muscles had a higher likelihood of developing moderate-to-severe chronic WAD symptoms, including persistent neck pain and disability. While this does not establish causation, it suggests that muscle degeneration may play a role in long-term recovery outcomes.

When muscles become underused or damaged, they atrophy (shrink), and as a compensatory process, the body gradually replaces lost muscle fibers with fat and fibrotic tissue. The deep neck muscles, which are important for maintaining balance and spinal stability, are particularly susceptible to injury during a whiplash event. If these muscles become injured, the superficial muscles used to consciously move the head and neck will be forced to take on these added functions. In the short term, this may not be a problem but over time, the deep muscles can weaken and atrophy allowing fat infiltration to occur.

This finding supports the importance of early chiropractic intervention and staying active to reduce the risk of WAD progressing to a chronic condition. Chiropractic care for WAD typically includes spinal mobilization, myofascial release, and neuromuscular retraining to improve joint mobility and restore proper muscle function. Additionally, chiropractors encourage patients to gradually return to normal activities within pain tolerances, avoiding excessive restriction of movement to help maintain muscle function, prevent stiffness, and promote recovery while minimizing the risk of re-injury.