Oregon-based Massage educator Whitney Lowe wrote on his blog that intervertebral discs can manage a high compressive load between the adjacent vertebrae.
“The idea many people have when they hear about a ‘blown-out disc’ is that some acute force caused a previously normal disc to rapidly protrude to one side as a result of the sudden force,” Lowe wrote. “In the lumbar region the blown-out disc is frequently suggested to result from lifting heavy loads and having sudden back pain.”
In fact, the lumbar spine at the L5 and S1 joint can sustain an average of about 4.4 kilonewtons (kN) (standard deviation 1.9 kN), or almost 1,000 pounds of compressive force, according to a 1989 study that examined 307 lumbar segments. That‘s about the weight of a touring motorcycle.
A 2007 study published in Spine showed that the cervical spine could withstand compressive forces of up to 2.4 kN, or about 540 pounds, among 22 subjects.
“If there is an acute disc herniation, it’s generally the last straw, occurring to a disc that was already protruding and seriously weakened,” Lowe wrote.
Some people who are diagnosed with a disc herniation does not always mean they have back or neck pain. A 2015 systematic review of 33 papers with a total of 3,110 subjects found a lack of pain associated with spine degeneration among a majority of the subjects.
“Disk degeneration prevalence ranged from 37% of asymptomatic individuals 20 years of age to 96% of those 80 years of age,” the authors wrote. About 30% of those in their twenties had a bulging disc compared to 84% among those in their eighties.
The researchers wrote that the degenerative changes on the spine and disc “may be part of normal aging and unassociated with low back pain.”
“The finding that 50% of asymptomatic individuals 30–39 years of age have disk degeneration, height loss, or bulging suggests that even in young adults, degenerative changes may be incidental and not causally related to presenting symptoms,” they concluded.
Another study from Japan that was published in Spine also found a similar pattern in the cervical spine among 1,211 adults between ages 20 and 70. These subjects show no symptoms of pain associated with cervical disc herniation. Even young, asymptomatic subjects in their twenties had a high rate of disc herniation (men 73%, women 78%).
“Commonly used expressions like the blown-out disc (or slipped disc; also erroneous because the disc doesn’t slip), often lead to inaccurate models of pathophysiology,” Lowe wrote. “As a result, treatment decisions may be based on these incorrect models and lead to poor outcomes. When you hear these types of phrases, make sure you understand the real underlying pathology and make treatment decisions based on accurate physiology.”
Nick Ng, BA
Nick Ng is the editor of Massage & Fitness Jounal and the managing editor for My Neighborhood News Network.
An alumni from San Diego State University with a bachelor’s degree in graphic communications, Nick had completed his massage therapy training at International Professional School of Bodywork in San Diego in 2014. In 2021, he earned an associate’s degree in journalism at Palomar College.
When he gets a chance, he enjoys weightlifting at the gym, salsa dancing, and exploring new areas in the Puget Sound area in Washington state.
