Blocking Inflammation After Surgery May Prolong Pain, Study Finds
A new study challenges conventional wisdom, suggesting that suppressing inflammation following surgery or injury could actually increase pain and delay recovery. Researchers found that allowing the body’s natural inflammatory response to run its course led to quicker pain resolution and overall healing.
The long-held belief in the medical community has been that reducing inflammation immediately after an injury would minimize pain. However, this recent investigation, published in the Journal of Pain Research, indicates the opposite may be true.
“The idea was that blocking inflammation would reduce pain overall,” explained a senior author of the study, an associate professor in the physiology department and the neuroscience program at Michigan State University. “Instead, blocking inflammation increased pain in the long run. It was an unexpected result.”
The research team utilized a mouse model to examine postoperative pain, comparing outcomes with and without activity of TNF-α (tumor necrosis factor alpha), a key immune signaling molecule. By inhibiting TNF-α – a process that promotes inflammation – and simulating surgery with a small incision, they anticipated a reduction in pain. Surprisingly, the mice experienced prolonged discomfort.
“It prevented the body from turning off the pain normally,” the researcher stated. Initial skepticism led to repeated experiments conducted by multiple lab members, employing three distinct methods to inhibit TNF-α, including the FDA-approved drug Etanercept. The consistent results confirmed the initial findings.
While the vast majority – 90% – of patients experience normal pain resolution after procedures ranging from tooth extractions to hip replacements, approximately 10% develop chronic postsurgical pain. This persistent pain is notoriously difficult to treat, often resistant to medication, and can endure for years. Considering that over 40 million Americans undergo surgery annually, this translates to an estimated 4 million individuals developing chronic postsurgical pain each year. The study suggests that the body’s ability to utilize TNF-α in response to surgical incisions is a critical determinant of whether pain resolves or becomes chronic.
Does this mean individuals should discontinue using over-the-counter anti-inflammatories like ibuprofen? Not necessarily. The body’s inflammatory response is a complex interplay of numerous molecules involved in pain and healing.
“We don’t have a good understanding of what is doing what, so the key will be to identify which molecules are contributing to pain and which are contributing to the resolution of pain,” the researcher said. “The goal is to target the bad and keep the good ones.”
The study specifically focuses on the impact of blocking TNF-α after surgery. The researcher clarified that there are still scenarios where inhibiting TNF-α may be beneficial, such as improving mobility by reducing inflammation in the joints for autoimmune diseases like rheumatoid arthritis.
“Inflammation is not necessarily a bad thing,” the researcher emphasized. “Yes, it hurts, but it’s also working on the inside to promote the resolution of that pain. The idea in the medical field that when you have an injury, you should absolutely block the inflammation right away might not always be the best strategy.”
Looking ahead, the researcher expressed optimism about the future of pain management. “Yeah, I do think so,” they said, when asked if it will one day be possible to block pain while still allowing the healing benefits of inflammation. “If not, I would do a different job.”
Source: Michigan State University.
