Back Pain Can Arise From an Injury, Sensitization, or Both

Source: Shutterstock/Roman Kosolapov

Two women in the emergency room sit across from each other, their eyes red and welling with tears. Watching the minute hand of the clock slowly tick by, they eagerly await their turn to be seen.

That morning, Linda had lifted a heavy box and, as she turned to put it down, felt a searing pain ignite in her back. The pain shot down her leg like it had been set on fire. The flames pulsed, each one burning more intensely than the last. The pain was unbearable.

Meanwhile, Nicole awoke with low back spasms and a fiery sensation enveloping her leg. Her spine muscles seized with a ferocity that made it hard to take a full breath. She had been struggling with back and leg pain for over a year now, but today was the worst. She couldn’t endure it any longer.

Same Pain, Different Problems

Linda and Nicole both have lower back pain with sciatic-like symptoms, but the source of their pain is different. Linda’s back pain stems from a herniated disc, while Nicole’s pain is from sensitization, also called “nociplastic pain.”

Nociplastic pain arises from abnormal pain processing in the brain and nerves. Nerves become more sensitive and reactive to stimuli exaggerating pain signals to the brain. Lifting a bag of groceries feels like moving a cement block.

Herniated disc. Linda experienced a herniated disc, which, in turn, irritated a nerve. Her injury responded well to the standard treatment of physical therapy and a steroid injection. She took nerve pain medication (gabapentin) for about six months. By nine months, the disc healed and, because the nerves were no longer getting the pain signal, Linda’s symptoms resolved.

Nerve sensitization. Nicole’s back pain arose from nerve sensitization. Her symptoms had slowly worsened over the past year. She developed pain hypersensitivity where simple, everyday movements—like getting up from the couch and walking to the kitchen—had become increasingly uncomfortable.

Her symptoms also spread. Instead of pain in a small area of her back, she felt it across her back, down her thighs, and along her entire left leg. Nicole experienced other symptoms, too, like difficulty sleeping at night, fatigue, and brain fog. She missed a lot of work because of the pain. Some days, Nicole couldn’t function.

She did not respond to standard treatments. Nicole had no benefit from physical therapy or a steroid injection.

Here are two people with similar symptoms, with varied responses to treatment because the source of their pain differed. Linda had a structural cause, a herniated disc. It caused swelling. The pain fibers signaled. The steroid reduced the swelling, which reduced the firing of the pain signal. The nerve calmed down over time. The body healed the structural issue over the next nine months.

Nicole, however, had disordered pain processing from nerve sensitization. There was no swelling irritating the nerve. Instead, Nicole’s disordered pain processing kept telling her brain she was hurt. Although an injury may have started the pain, it was no longer the factor perpetuating it. Over the past year, the pain source had shifted—from an injury to the nervous system. Sensitization maintained the pain after the injury had healed.

Since the source of Linda and Nicole’s pain was different, their treatment was different. Linda did well with standard treatments focused on injury-related inflammation because she had an injury, a herniated disc. Nicole did not respond to standard treatments because the pain was no longer from the disc or nerve, but from abnormal pain processing in the brain. The correct target for her treatment was the nervous system.

You don’t put a cast on a paralyzed arm from a stroke because the cause of the injury isn’t in the arm; it’s in the brain. The problem is deeper, in the nervous system. The same is true when treating sensitization. I expand on this further in my book, Sunbreak: Healing the Pain No One Can Explain.

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Nociplastic pain can occur by itself or as a mixed pain state where there is injury pain and sensitization pain. For example, with chronic back pain, discomfort can arise from the injury area (herniated back disc) and sensitization. Sensitization amplifies the pain signal that is already present. The difficulty is the two pain sources overlap into one set of symptoms. The three possible pain scenarios are:

1. Back pain from an injury with no sensitization, meaning the nerves have not become sensitized; this situation will respond well to standard treatments. This was the case with Linda.

2. Back pain from an injury and sensitization; in this case, there will be a partial response to standard treatments. This is a “mixed pain state.”

3. Back pain with predominant sensitization, where most of the symptoms stem from sensitization; there is minimal response to standard treatments. This was the case with Nicole.

Standard treatments don’t work when the pain comes predominantly from sensitization because the dysfunction has shifted to the nervous system. The more sensitization drives the symptoms, the less responsive they are to standard treatments, including spine procedures.

Procedures not only fail to help with nerve sensitization, but may worsen the pain. If nerves are hypersensitive, the last thing you want to do is take a scalpel to the area and make more pain inputs that will be amplified and sent to the brain!

With chronic back pain, you must treat the correct source of the symptoms.