Why We Feel Pain and Why It Can Last So Long
Third in a series
Maybe it’s just a persistent annoyance, or maybe it keeps you awake at night or even keeps you confined to the house, unable to work or do the things you enjoy.
Long-lasting (chronic) pain affects one in five U.S. adults. For almost half of them, about 8% of adults, pain limits everyday life or work.
In many cases, it starts with an injury, but never goes away. Or the cause may be a slow wear and tear of muscle, bone and joints with age.
In the last two decades, U.S. doctors trying to provide relief to their patients prescribed more and more opioid medications. Newer versions were marketed as safe, but millions of Americans became addicted. Some continued to suffer even when taking high doses.
Now Einstein, like most other healthcare systems, has swung toward other treatments for newly acquired pain as doctors also work with patients to reduce their use of opioids for chronic pain. There are many other treatments that help people to manage or even eliminate pain without opioids.
However, it may take time, patience and several different approaches to improve pain that has been around for a while (chronic pain). If you have lingering pain, it’s important to better understand how pain works in the body.
What Is Pain?
So, what is pain, and why is it sometimes so hard to get rid of?
Here’s a brief explanation, based in part on the work of pain expert Lorimer Moseley, of the University of South Australia.
Biologically speaking, the purpose of pain is to alert the body to danger. “You need pain,” says Leonard Kamen, DO, a physiatrist at MossRehab who specializes in rehabilitation and pain management. “It’s part of our defense network that helps protect us from injury and threat.”
Let’s say you’re walking barefoot, and you step on something hard – the pain gets your attention, and you pull your foot away.
Behind that seemingly instantaneous response lies a complicated series of signals that takes place between your foot and your brain and spinal cord.
“So where is pain?” Dr. Kamen says. “Is it in your foot? No, it’s transmitted through an intricate network in the brain, nervous and emotional systems of the body.”
Why is this an important thing to know about chronic pain? Because it shows that pain – all pain – in a sense is “in your head,” namely the brain. It depends on the brain’s ability to analyze and interpret stimuli from your environment to determine the level of threat to your body.
Why Can Pain Last After an Injury Heals?
When all goes well, the pain response protects you from danger. But the brain can sometimes make errors, causing pain when the danger has passed or doesn’t exist.
Let’s go back to your barefoot walk. When you step on something hard, here’s a simplified version of what happens:
- Nerve endings in the skin send signals to the brain and spinal cord alerting them that your foot has been touched.
- The spinal cord sends signals to the brain saying something possibly dangerous has touched your foot.
- The brain evaluates the danger level based on the new information plus your previous experiences.
- The brain decides there’s some danger and so sends signals back to your foot, causing pain.
But every bit of pain you experience changes how the brain evaluates the danger, and how much pain the brain generates as a warning. In essence, the body gets better at producing pain. And so you may have the same or increased pain in a body part, even if the original injury has healed.
This phenomenon is called sensitization, and it’s often the cause of chronic pain.
“Sensitization reflects the memory of prior pain in our brain and nervous system,” Dr. Kamen explains. “It’s often triggered by stress or anticipation of pain from a previous experience.”
The pain is real, even though whatever triggers it – moving a certain way or being touched lightly – may present no danger to your body.
Where Do Opioids Fit In?
People may take opioids because of pain after surgery, or from an injury. Prescription opioids include hydrocodone or oxycodone, which are often combined with other pain medications, as in Vicodin and Percocet. Doctors may prescribe these medications to help people through the healing process.
Some people may end up with a prescription for opioids because other medications, such as acetaminophen (Tylenol) or ibuprofen (Advil, Motrin) don’t take their pain away.
Most of those taking opioids stop after a few days or weeks, as prescribed by their doctors. Opioids can cause drowsiness and other side effects, such as constipation. Although many people have used them safely, opioids also can lead to addiction, overdose and death.
For others, stopping is harder. People may ask their doctors for larger and larger doses – and still have pain. How can this happen?
- People can develop tolerance to opioids, so that their original doses no longer have the same effect.
- Sensitization can make pain feel more intense.
Research has found that long-term use of opioids is barely more effective than a placebo for reducing pain.
What Are the Alternatives to Opioids?
Because pain is a complex process, involving the bones, joints, muscles, other tissues, nerves, spinal cord and brain, many people with chronic pain benefit from a multi-pronged approach. At Einstein, doctors and other health professionals use many of the treatments below to treat short-term or long-term pain.
Research has found these therapies to be helpful, separately or in combination.
Physical therapy – Movement is extremely important for strengthening muscles and other tissues that support the body. Physical therapists work with people who are injured or in pain to gradually help them recover using exercises, massage, heat, cold and other techniques.
Injections – Pain specialists can inject numbing agents and steroids into the area around a joint, specific nerves or the epidural space of the spinal cord to reduce inflammation and pain. The effects of these treatments typically last several months – in some cases longer – and allow a person to participate in physical therapy and other longer-term solutions.
Procedures – Some conditions may be helped by minor procedures. One type of procedure burns away tissue that is causing the pain signals. Other procedures implant devices that stimulate certain nerves or pump medications to block pain signals. These treatments can provide longer-term results than injections.
Other medications – Much long-term pain is caused by either sensitization or an injured or compressed nerve. For this reason, taking medications that act on the brain and nervous system can allow people to taper off and even stop taking opioids while relieving pain. Examples include certain anti-seizure medications and antidepressants.
Alternative treatments – Medical marijuana is one alternative option for Einstein patients dealing with chronic pain.
Medication-assisted treatment – Medications such as buprenorphine, naltrexone and methadone are used to treat potentially life-threatening addictions to opioids and allow people to recover and avoid overdose.
You can learn more about these treatments in other articles of this series.
Finally, a healthy lifestyle – including exercise, stress management, weight loss and healthy eating habits – contributes to overall health and can reduce strains on the body that cause pain or make it worse.