Chronic pain requires multidisciplinary approach, patient commitment for effective treatment

Ms. Choi, a 65-year-old woman, has been experiencing severe chronic back pain. She has undergone various hospital tests but could not find a specific cause and diagnosis. Recently, the pain spread to both legs, causing her to suffer from insomnia and depression.

After visiting the Chronic Pain Clinic at Soon Chun Hyang University Hospital Bucheon, Choi received a medial branch nerve-blocking operation, and her pain improved.

Chronic pain is a condition in which pain caused by trauma or disease persists for more than three months, even after appropriate treatment, or becomes more severe. Because it is difficult to diagnose and treat because of various pain patterns and causes, the patient's willingness to treat and lifestyle improvement are the most critical factors in overcoming chronic pain.

“Pain like being on fire, feeling like electricity, and pain that tears the skin are symptoms that patients with chronic pain complain of,” said Professor Chung Moon-young of the Department of Neurosurgery at the hospital’s chronic pain clinic. “Chronic pain does not threaten life, but it is a condition that significantly reduces the quality of life beyond the discomfort of living. Therefore, it must be treated.”

The most common chronic pain conditions include chronic headaches, chronic low back pain, and complex regional pain syndrome.

Other conditions include post-spinal surgery pain, phantom limb pain, fibromyalgia, trigeminal neuralgia, and cancer pain.

“According to the Health Insurance Review and Assessment Service (HIRA), the number of ‘medial branch nerve block,’ which blocks nerve for patients with chronic low back pain, one of the typical chronic pain conditions, increased from about 100,000 cases in 2010 to 1.8 million in 2023. Chronic pain is expected to increase as life expectancy increases and disease management becomes more sophisticated due to social development,” Chung said.

The main symptom of chronic pain is paresthesia. Patients complain of sensory irritation in the absence of any stimulus. This sensation is not limited to the initial painful area. Still, it spreads to neighboring areas, changes sensory patterns, and even travels around the body. Gastrointestinal symptoms, including indigestion and vomiting, and psychiatric symptoms, including anxiety and depression, can also accompany it.

The most likely cause of chronic pain is considered to be “abnormalities in the sensory nervous system.” According to the 2018 International Classification of Diseases (ICD-11) revision, the abnormal perception of pain due to nervous system abnormalities is collectively called “chronic primary pain.” The main risk factors include personal predisposing factors, including female gender, advanced age, and a history of surgery; psychiatric factors, including depression and post-traumatic stress syndrome; and social factors, including physically hazardous jobs, lack of exercise, and substance abuse.

The diagnosis of chronic pain is based on a “diagnosis of exclusion” that eliminates the most likely diagnoses. In the case of chronic low back pain, imaging tests, including MRIs and CTs of the spine, are used to identify the source of the pain. These tests are followed by tests, including electromyography, and diagnostic procedures, including nerve blocks. If no clear lesion causes the pain after all these tests and procedures, the diagnosis is chronic pain.

The main treatment for chronic pain is medication. Over-the-counter painkillers are often ineffective, and tricyclic antidepressants or anticonvulsants, which modulate the activity of the pain transmission pathways in the brainstem, are used first. If the pain persists despite medication, a nerve block or an injection procedure may be performed.

If the symptoms do not improve after this, surgical treatment, such as nerve decompression or neurotomy of the offending nerve, may be considered. If the culprit nerve is unknown, a neurostimulator may be inserted into the spinal cord to deliver continuous electrical stimulation to control pain in a specific body area. If that doesn't work, a procedure called a nucleotomy may be performed to remove the nucleus accumbens, which is the final gateway for the brain to recognize pain.

To prevent chronic pain, it's important to lead a healthy lifestyle.

Avoiding overeating, drinking too much alcohol, and smoking, along with a healthy diet, regular exercise, and a healthy leisure lifestyle, can help. Aerobic exercise, including jogging or swimming, stretching exercises such as yoga to improve joint mobility, and strength training to strengthen muscles can help. Avoid simple sugars, including sugar and liquid sugars; eat foods high in unsaturated fatty acids, such as fish and legumes; consume vegetable fiber; and drink plenty of water.

“Chronic pain is a disease that requires multiple diagnoses and methods to get closer to a cure,” Professor Chung said. “That explains why it is not only the doctor's prescription, technique, and success of the surgery but also the patient's willingness to be treated.”

“Because it is difficult to find a clear pathology or cause of chronic pain, patients are often misunderstood as having a disease or mental illness. While pain can interfere with sleep and lead to depression or anxiety, it is a misconception that mental illness causes pain,” Chung said. “It's important to treat patients without misconceptions and prejudice, as this can be a barrier to further addressing pain.”