Pain

Osteoarthritis: Understanding Risk Factors & Effective Management

According to the World Health Organization as of 2019, 528 million people world wide were living with osteoarthritis, a more than one hundred percent increase since 1990. Osteoarthritis is the most common type of arthritis, affecting primarily the knees, hips, hands and spine. In this post I will write about the risk factors for developing osteoarthritis, both the ones you can’t do anything about and the things you can do to reduce your risk of developing osteoarthritis. Since osteoarthritis is so common, I will also write about the best way to manage osteoarthritis if you already have it.

Risk factors you can’t modify

Age

73% of people with osteoarthritis are over 55. The risk of osteoarthritis increases with increasing age. According to data from the CDC, osteoarthritis occurs in 3.6% in adults ages 18–34 to 53.9% in those age 75 and older.

Gender

The CDC estimates that about 1 in 4 women have been diagnosed with osteoarthritis, compared to about 1 in 5 men. The percentage of women with osteoarthritis increases after menopause. For example, among people aged 40–49, about 10% of women and 7% of men have knee osteoarthritis, but between the ages of 60–69, that prevalence rises to 35% in women and 19% in men.

Genetics

There is no gene for osteoarthritis. The genetic risk of osteoarthritis is the result of many genes, each contributing only a small amount of risk. The total genetic contribution to osteoarthritis is about 30%. In other words a little less than a third of cases of osteoarthritis are due to genetic factors.

History of joint trauma or injury

Any injury to a joint or a fracture involving a joint increases the risk of post traumatic osteoarthritis. For example the incidence of arthritis of the knee after ACL tears is as high as 60%.

Risk factors you can modify

Obesity

Maintaining the lowest weight that is practical for you reduces your risk of developing osteoarthritis of the hip and knee. Obesity markedly increased the risk of developing osteoarthritis and also serves as a multiplier for other risk factors.

Sedentary Lifestyle

Aerobic exercise and strength training decrease the risk of developing osteoarthritis. The best practice is to follow CDC recommendations: 150 minutes per week of moderate exercise such as brisk walking or 75 minutes of vigorous exercise such as running or cycling. Strength training twice a week.

Smoking

Smoking causes inflammation and double the risk of getting osteoarthritis. It is best to never start smoking. If you smoke, stopping smoking decreases your risk, although not as much as if you never smoked

Avoiding Certain Occupations and Sports

Occupations that involve long standing, bending and heavy lifting increase the risk of osteoarthritis, especially of the knees. They include workers in construction, firefighting, agriculture, fisheries, forestry, and mining. In a case-control study, men who worked for 11–30 years in building and construction work had a 3.7 fold greater risk of developing knee osteoarthritis.

Certain sports such as American football, soccer, competitive wrestling and competitive weight lifting are also associated with increased risk of osteoarthritis of the knee and ankle. There is conflicting evidence about long distance running. Some studies show increased risk, but one study showed that marathon runners have decreased risk of developing osteoarthritis.

How to manage osteoarthritis of the knee

Weight loss

If you are significantly overweight or obese then weight loss will decrease stress on the knee thereby reducing pain and slowing the progression of the arthritis.

Exercise

Aerobic exercise helps pain from knee arthritis. The best exercise is walking or swimming or water aerobics. Strengthening exercises for the quadriceps muscle are also helpful. Here is a link to a good description of quad strengthening exercises: Knee Arthritis Exercises. Physical Therapy can also be helpful and can provide equipment like braces or heel wedges that can also reduce pain. There is also some evidence that tai chi reduces knee pain from knee arthritis. If you smoke, stopping smoking can reduce inflammation and therefore pain.

Medicines

The first medicines to try with the least potential for side effects are topical medicines that you rub on the knee. The most effective ones are diclofenac and capsaicin. Both of these are available over the counter. Topical lidocaine patches can help temporarily, but don’t last as long as the other two.

Oral medicines that are the most effective are NSAIDs like naproxen or ibuprofen in combination with acetominophen (Tylenol). Long term use of oral NSAIDS can occasionally cause bleeding ulcers or kidney damage. If you are taking NSAIDs long term, these need to be monitored by your doctor.

Alternative treatments like glucosamine, ginger and S-adenosylmethionine (SAM-e) seem to help some people and are safe long term. Chondroitin has not been shown to reduce pain.

Joint Injections

Steroid injections in the knee can give temporary relief. This can last for months. These are generally safe every 3 months for up to a year. These injections are easy to administer and can be done by most family physicians without need for referral. Over time, as arthritis worsens they tend to not work as well. Multiple steroid injections have been shown to worsen arthritis, so fewer injections are better.

Cartilage injections have shown no difference from placebo in controlled trials. Some people get some benefit, but this may well be a placebo effect.

Surgery

The only surgery shown to be effective is total or partial knee replacement. Arthroscopic knee surgery to “clean out the joint” has been shown to have no more than placebo effect.

How to manage osteoarthritis of the hip

Exercise

All of the aerobic exercise options for knee osteoarthritis also work for osteoarthritis of the hip, but water exercise or cycling is better than walking. Avoiding certain activities that stress the hip such as stair climbing, or active sports like tennis can reduce pain. Tai chi can also be helpful for hip osteoarthritis. Canes or walkers can be helpful, but need to be prescribed by a physical therapist who can decide on the best appliance and show how to use it properly.

Medicines

Topical medicines do not work as well for osteoarthritis of the hip as well as they do for the knee. Oral medicines are the same as medicines for osteoarthritis of the knee.

Joint Injections

Steroid injections of the hip can be helpful but have to be done using ultrasound or x-ray to make sure the needle is in the hip joint. They are much more difficult than steroid injections of the knee.

Surgery

Hip replacement is the only surgical option. It tends to be less painful post operatively than knee replacement and requires less rehabilitation by physical therapy.

How to manage osteoarthritis of the hands

Home management

Home management includes periodic resting of the hands when doing repetitive activities such as typing. Heat also helps. A warm compress or paraffin wax hand bath can soothe affected joints.

Some adaptations of daily activities may be helpful. Here are some suggestions from Arthritis Health by Veritas:

  • Wear coats and shirts with zippers instead of buttons
  • Use long zipper pulls which are also larger than regular zipper pulls and therefore easier to grasp. Specialized zipper pulls are made with looper cloth or nylon and allow the user to stick a finger through and pull down.
  • Choose lightweight cooking and gardening tools that are easier to lift and hold
  • Buy slip on shoes to avoid having to tie shoelaces

Occupational therapy can provide hand exercises as well as splints and other home aids.

Medicines

Topical medicines also work well for hand and wrist osteoarthritis. The other medicines for knee osteoarthritis also can be helpful.

Joint Injections

Steroid injections can be very helpful, but are somewhat more difficult to do than knee injections. Hand or wrist steroid injections are usually done by an orthopedist or rheumatologist.

Surgery

Surgery for hand osteoarthritis is not done very often and when done usually involves fusion of a joint to relieve severe pain.

Management of Osteoarthritis of the spine

Osteoarthritis can happen in any part of the spine, but osteoarthritis in the lumbar spine is the most common. The symptoms are back pain, and if a nerve root is compressed, then the pain can radiate down one leg (or one arm if the arthritis is in the cervical spine). Treatment depends somewhat on the symptoms, but like other forms of osteoarthritis non-medication treatment includes exercise, weight loss, tai chi, and physical therapy. Acupuncture helps some people. TENS units sometimes help as well. If you smoke, stopping smoking decreases inflammation and therefore pain.

Medicines

The same topical and oral medicines for knee arthritis also help for spinal osteoarthritis.

Injections

Epidural (just outside the spinal cord sack) injections can be helpful and when they work can last for months or even years. They have to be given by a pain management specialist under x-ray guidance.

Surgery

There are several kinds of spinal surgery. If the spinal osteoarthritis is severe enough to cause pressure on the spinal cord, then part of the vertebrae compressing the spinal cord are removed and the vertebrae are fused. If just the opening between the vertebrae is pressing on a nerve, then that opening is enlarged to take pressure off the nerve root. Surgery can also involve fusion of vertebrae at one or several levels to decrease pain. This kind of fusion surgery is not always successful long term and should be avoided if possible.

Bottom Line

Osteoarthritis is the most common form of arthritis and prevalence increases with age. Over half of people over 75 have osteoarthritis. Women are more commonly affected than men, especially after menopause. Thirty per cent of osteoarthritis is genetic and the rest due to other risk factors including previous joint trauma, obesity, smoking, sedentary lifestyle, certain occupations and certain sports. Avoiding obesity altogether or losing weight if you are overweight, regular aerobic exercise as well as strength training twice a week and stopping smoking if you smoke all decrease your risk of developing osteoarthritis. For those who have osteoarthritis Non-medication treatments should be tried first. Surgery is a last resort when other methods have failed.

Palliative Care and Hospice: What Families Need to Know

Despite all our activities to reduce our population risk of disease and death, illness, suffering and death eventually come to all of us. This post is about what resources you can draw on when illness and suffering happen to your loved ones. The terms palliative care and hospice are often misunderstood. Hopefully after reading this post you will be clear about what these terms mean and how you can use services that provide either or both palliative care and hospice to reduce suffering in your loved ones who have serious illness or are approaching the end of their lives.

Palliative Care

Many people think of palliative care as end of life care. That is a misconception. Palliative care aims to reduce suffering in anyone who has a serious illness, even if they are likely to recover. Palliative care specialists are available in most hospitals and in some areas will do home visits. Palliative care can improve quality of life and can help patients understand their choices for medical treatment. Palliative care services may be helpful to any older person having a lot of general discomfort and disability very late in life. People receiving palliative care can continue other treatments such as chemotherapy for cancer, surgery, or any other potentially curative treatment.

Palliative Care Team

There is usually a palliative care team made up of one or more palliative care specialist doctors and may also include nurses, nutritionists, social workers, chaplains and physical therapists.

Palliative Care Example

Mrs S.is a 75 year old woman who lives alone. She has recently been diagnosed with ovarian cancer. She has a good chance of cure with chemotherapy and she has decided to agree to chemotherapy. Her doctor recommends palliative care during her chemotherapy to help her with pain, fatigue, loss of appetite. The nutritionist on the team helps her find foods that she can eat and monitors her weight. The palliative care specialist helps with medicines to manage her pain to keep it at a tolerable level. The social worker on the team helps find volunteers to do her grocery shopping when she is too tired to go herself. The physical therapist on the team helps her with balance and does a home assessment to decrease her risk of falling. The chaplain on the team calls her periodically and visits as needed to help her deal with the emotional pain of her illness.

Palliative Care Resources

Here is a link to a website that lets you put in your address to find palliative care resources in your area: Palliative Care Provider Directory.

Hospice

Hospice provides comfort care at the end of life. It is available if a physician certifies that death is likely to occur within 6 months. Hospice services make the end of life much more comfortable for almost all patients. Unfortunately many people do not access hospice services until days before death. More than half of Medicare patients who are eligible for hospice received hospice care less than 30 days before they died. One fourth of these die within a week of beginning hospice.

There are many reasons why families tend to delay seeking hospice benefits. Here is a link to an excellent website that discusses reasons why families delay and that also describes how hospice helps people nearing the end of their lives: Why Family Members Wait Too Long to Call Hospice.

Hospice Benefits

Hospice covers all medicines needed for comfort including pain medicines. Hospice also covers certain medicines for chronic disease like blood pressure and diabetes medicines, since stopping these could increase patient discomfort. Hospice also covers hospitalizations for certain acute illnesses or injuries where hospitalization is necessary for patient comfort. Hospice is almost always delivered by a team that may include a physician, nurse, hospice aide, social worker, volunteer, chaplain, and bereavement specialist. 

Hospice Eligibility

People who are undergoing curative care are eligible for palliative care, but not hospice. People who have a projected life span of 6 months or less are eligible for hospice. If a person lives longer than 6 months, that does not mean hospice benefits are terminated. If the person still has a projected lifespan of 6 months, hospice benefits continue no matter how long they actually live. If the prognosis improves to the point that the projected lifespan is more than 6 months, then that person is no longer eligible for hospice. If the prognosis worsens again, then hospice benefits are available again. For Medicare, at least, hospice benefits are never exhausted, no matter how many times a person goes on and off hospice.

For people who do not have Medicare, private insurance usually pays for hospice care. Medicaid also pays for hospice care.

Who delivers hospice care?

In rural areas there may be only one hospice provider, but in most areas of the country there are several different agencies that provide hospice care. Although they all have to provide the same basic services, there are differences between providers that make a difference to hospice patients and their families. Your doctor may recommend a hospice provider, but there are some important questions to ask the hospice provider. Here is a link to the Hospice Foundation of America website that gives advice about how to choose a hospice provider and what questions to ask: How to Choose a Hospice Provider.

Hospice Example

A 93 year old man living with his daughter has gotten progressively more frail and with mild dementia. He cannot perform activities of daily living such as toileting, bathing and dressing. His doctor certifies that he is likely to die within the next 6 months, so he qualifies for hospice care. Because of the excellent care he gets from hospice, his condition improves and hospice care is discontinued. He also has congestive heart failure, and over time this gets much worse. He again qualifies for hospice, and the same agency takes care of him again until his death about 8 months later at age 94.

Bottom Line

Palliative care and hospice are not the same thing. Palliative care focuses on comfort for people with serious diseases even when those diseases are curable. Hospice care is end of life care and is a Medicare benefit. It is available for people who have a probability (not certainty) of dying within 6 months. Both palliative care and hospice are seriously underused by people who could benefit from them.

The Power of the Unconscious Mind: How to Access it for Healing and Improving Health

I’m going to spend some time in this post writing about the neuroanatomy and function of the conscious and unconscious mind. Hopefully I will be able to clear up some common misconceptions about both. I will then write about the amazing power of the unconscious to facilitate healing from both physical and psychological injuries as well as to decrease pain from dental and surgical procedures. Finally I will write about how to use self hypnosis techniques to access the power of the unconscious.

The Conscious Mind

We intuitively feel that our conscious mind makes up the largest part of who we are. Through our 5 senses we feel that we observe the real world, that is, what we see, hear, touch, smell and taste is out there in the world just the way we perceive it. That is an illusion, however. We perceive what is important for our survival. We see only a small part of the electromagnetic spectrum. We cannot see ultraviolet, for example, but bees can. We hear sounds of only certain frequencies. Dogs can hear ultrasonic frequencies, and dogs’ sense of smell is thousands of times better than ours. We do not directly sense the world. Information from our sense organs is extensively processed in the brain. We sense only a representation of the outer and inner world that our brains create. Furthermore a vast amount of sensory information is coming from our environment, both internal and external, being processed by our sense organs, and we become conscious of only a tiny part of that input. Our conscious minds can process about 50 bits of information per second. If that sounds like a lot, remember that internet download speeds are measured in millions of bits per second. The parts of your brain and spinal cord that are below the level of consciousness process about 11 million bits of information per second!

Carl Jung once described the conscious mind as like a cork floating on the sea of the unconscious. Modern neuroscientists have shown that his analogy was very accurate.

An example may make this point better. As you are reading this blog, you are seeing the letters and words upright. What is actually happening is the light and dark pattern of this sentence is focused by the lenses of your eyes into upside down two dimensional images on your retinas. A great deal of processing goes on in your brain so that what you actually perceive is right side up, has color and is three dimensional. All of that processing is below the level of consciousness. Furthermore, the high resolution part of your retinas, called the fovea can see only a small area at a time. Your eyes are constantly scanning back and fourth and up and down seeing only a tiny bit at a time and yet you perceive your visual world as whole. Finally your ability to read sentences and extract meaning rather than seeing individual letters and/or words is a learned pattern that has become automatic. Most of the process of reading is therefore done below the level of consciousness.

The Unconscious Mind

As you can see from the section above, the vast majority of the processing our brains do is below the level of consciousness. The unconscious mind controls our heart rate, our blood pressure, our breathing, our bowel function and all the things that are are necessary for our survival that we don’t have to think about to make them happen. The unconscious also contains all of our of automatic skills, such as playing the piano, riding a bicycle, or playing tennis. It is the source of stored memories, fantasies and dreams. It takes over patterns that we have learned over time to simplify our lives. Many of these patterns are necessary and helpful, such as brushing our teeth. Some patterns are not so helpful, such as phobias, anxiety and fear, or unhealthful habits such as smoking, excessive drinking or compulsive drug use.

All of these things are patterns of connections in the brain. We used to think that brain connections once made could not be changed, but scientists have since found out that not only can brain connections be changed, but they are constantly changing. This is called neuroplasticity. It is normal to grow new brain cells and to change their connections.

Can we change unhealthy patterns in the unconscious mind?

The short answer is yes! While the unconscious mind is generally not accessible to the conscious mind (that’s why it’s called the unconscious, after all), there are ways to influence the unconscious mind and to change unhealthy connections.

Altered States

The state of mind that we are in most of the time is called the waking state. Our conscious mind is controlling our actions (well sort of). There are other states of mind, often referred to as altered states or trance states. These are familiar to all of us. A perfect example is watching a movie or a television show. We get so wrapped up in the story that we lose awareness of all of our other surroundings. Sometimes people talk to us while we are paying rapt attention and we don’t even hear them. Reading a really good book creates the same altered state. Have you ever been driving somewhere and suddenly found yourself having arrived at your destination, but you don’t remember any of the details of the trip? Another altered state of consciousness or trance. If the word trance bothers you, think about the word entranced. We all know what that means. These altered states or trances are no different.

It turns out that once we get the conscious mind out of the way (entranced) the unconscious mind becomes accessible to change. The spontaneous trance states like television watching or driving while in a trance don’t change any connections, but it is possible to intentionally go into a trance state and purposefully change connections in the unconscious mind.

Hypnosis

Many people find this word scary, but all it means is going into a trance state (which we do spontaneously all of the time) and changing some connections in the unconscious mind. That can happen accidentally and accidental changes are often not healthy ones.

So all hypnosis is really self hypnosis. Some people, called hypnotists, become very good at helping us enter trance states and facilitate positive changes in connections in the unconscious mind. Good hypnotists, however are few and far between. Most people who advertise themselves as hypnotists are not very good. A few people respond to them and they say the rest can’t be hypnotized. They blame their incompetence on the people they are trying to help!

You don’t have to find a skilled hypnotist in order to make positive changes in the connections of the unconscious mind. There are tried and true techniques that allow you to purposefully enter a trance state and make all sorts of positive changes in the unconscious. Furthermore you can activate pathways in the brain and spinal cord that release endorphins and norepinephrine that eliminate or markedly reduce pain. You can use these techniques at the dentist or for medical procedures that would normally cause pain.

Self Hypnosis

There are three things you need to do before each self hypnosis session.

  1. Decide how long your self hypnosis session will last. Twenty to thirty minutes is plenty.
  2. Decide what change you want to make. You can say it out loud or just think it. The change needs to be positive. The unconscious is very literal and it does not understand “not.” If you frame your change as “I’m not going to smoke anymore” The unconscious will take that as a command to keep smoking. A positive wording might be “I will just do things that improve my health.” Once you have framed a positive change, your unconscious mind will take over once you are in a trance. You don’t have to, nor should you repeat the instructions for change while you are in a trance.
  3. State out loud or in your mind how you want to feel after the session. It will either be “I will feel rested and refreshed” or “I will be tired and ready for sleep.” If you are doing your session just before bedtime you would say “I will be tired and ready for sleep.” Any other time of day you would likely want to feel rested and refreshed.

Induction of Trance

Going into a trance on purpose is called an induction. There are many ways of inducing trance, but I’m going to give you two very simple ones. You can try them both and see which one you like better. The first one was invented by Mike Mandel, a Canadian hypnotist. The second one has been around a long time and no one knows who invented it.

Incremental Eye Closure Induction

Find a quiet place where you are unlikely to be interrupted. Be sure to silence your phone. Sit in a comfortable chair and pick something to look at above your eye level. As you stare at whatever you have chosen, start paying attention to your breathing. With each out breath let your eyelids close a tiny bit. You will find yourself progressively relaxing, and by the time your eyelids close completely you will be in a trance. The trance will continue to deepen for a while with each out breath. You don’t need to do anything at this point except enjoy feeling relaxed and comfortable. Your unconscious mind will take care of the rest and you will find yourself returning to your waking state after the length of time you specified. You will feel great, rested and refreshed or tired and ready to go to sleep depending on which state you specified beforehand.

Instant Eye Closure Induction

Same instructions as above about a quiet place and a comfortable chair. As you inhale deeply, roll your eyes up as high as you can. As you exhale, close your eyelids with your eyes still rolled up, let your head drop forward and completely relax. You will instantly be in a trance. Your trance will deepen with each out breath. Once again, simply enjoy feeling so relaxed and let your thoughts go wherever they will. Your subconscious will bring you back to your waking state at whatever time you specified before the induction.

Practice

I would suggest that you do this self hypnosis exercise for at least 20 minutes a day (More is okay too). You will find with practice that it gets easier and quicker to induce a deep trance. Either eye closure method works as what’s called an anchor. As you practice you will find eventually that simply closing your eyes induces a trance. If you have to have any procedure that usually causes pain, you can give your unconscious mind instructions to feel relaxed and comfortable during the procedure and then put yourself in a trance during the procedure.

Bottom Line

Our conscious minds can only process 50 bits per second while our unconscious minds can process 11 million bits per second. The vast majority of mental processing takes place below the conscious level. Unhealthy connections in the unconscious mind take place by accident when we are in spontaneous trance states. It is possible to remove unhealthy connections and create new healthy connections by self hypnosis techniques. These technique can also diminish or eliminate pain from dental and/or medical procedures. Regular practice creates “anchors” that produce trance very quickly.

Chronic Pain

Chronic pain extends beyond the healing of the injury that may have triggered it. It is defined as pain that lasts more than 6 months. Unlike acute pain, it serves no useful warning function. Chronic pain is not just acute pain that lasts longer, but involves different areas of the brain and spinal cord. One in five people in the US and Europe and one out of three people in China suffer from chronic pain. Disability from chronic pain, particularly chronic back pain costs society about 600 billion dollars a year, which is double the cost of cancer, heart disease and diabetes.

Although research has increased our knowledge of the mechanisms of chronic pain, there is still no effective treatment. Opioids, which work well for acute pain and pain at the end of life, do not work very well for chronic pain. Although they might provide some temporary relief, in the long run they make the pain worse. Opioid overdose has become one of the leading causes of death in the US.

In this post I will talk about the latest research about the mechanisms of chronic pain. Although we don’t have good treatments to reduce chronic pain, there are some interventions that reduce suffering from chronic pain and I will talk about those as well.

Types of Chronic Pain

Chronic pain can be divided into several types:

  • Chronic Primary Pain. This kind of pain is not related to injury. It includes things like fibromyalgia and myofascial pain syndrome.
  • Chronic Cancer Related Pain. Certain cancers can cause chronic pain even when the cancer is in remission
  • Chronic Post Surgical or Posttraumatic Pain. This kind of chronic pain starts with an injury or surgery as acute pain that transforms into chronic pain
  • Chronic Neuropathic Pain. This kind of chronic pain results from injury to the nerves or spinal cord.
  • Chronic Secondary Headache or Orofacial Pain. All of the secondary chronic pain conditions have a specific cause that starts the chronic pain. Fixing the cause, if it can be fixed, may not fix the pain.
  • Chronic Secondary Visceral Pain
  • Chronic Secondary Musculoskeletal Pain

Even though there are different types of chronic pain and different parts of the body where chronic pain is experienced, the mechanisms and pathways in the nervous system for chronic pain are the same. Chronic pain leads to actual structural changes in the brain and spinal cord.

Central Sensitization

Chronic pain starts with sensitization of the pain pathways in the spinal cord. This appears to be caused by inflammation in the nerve cells of the pain pathways. They start to respond with pain signals to any input from the skin nerves and often they just fire off on their own. The inflammation in the spinal cord is caused by chemicals called cytokines. Different people release different cytokines and some are more prone to cause chronic pain than others. That means that some people are genetically more likely to develop chronic pain. Not only a person’s genetic makeup, but which genes are expressed or inhibited also effect the genetic susceptibility to chronic pain. These are called epigenetic changes and these can be affected by a person’s life experience. People who have experienced trauma in childhood, called Adverse Childhood Events are also epigenetically more likely to develop sensitization of pain pathways and thus chronic pain.

The sensitization also spreads to structures in the brain, particularly in the medial pathway that goes to the emotional centers in the brain (see my previous post Pain to review the thee pain pathways in the central nervous system). These changes are associated with actual loss of nerve cells in those emotional centers.

Descending Pain inhibitory pathway in chronic pain

A meta-analysis of 92 studies of people with chronic pain showed that the lateral and the medial pain pathways were still active, but the descending pain inhibitory pathway was not. This suggests that at least part of chronic pain may be due to a deficiency in the descending pain suppression pathway. This may be particularly true for primary chronic pain syndromes like fibromyalgia and myofascial pain syndrome.

Chronic Pain as learning and memory

Pain is intimately connected with memory. From an evolutionary perspective it was important for animals to remember the conditions that led to pain so that they could avoid those conditions in the future. It appears that memory is part of what maintains chronic pain. The medial pain pathway, the pathway that goes to the emotional part of the brain also goes to the temporal lobes where memories are created. There is some evidence that chronic pain may be (a reward driven) maladaptive learning process analogous to the memory of traumatic events that cause PTSD.

The Microbiome

The billions of bacteria in our GI tracts are intimately involved in our health. They produce signal molecules that regulate inflammation and sensitization of the central nervous system. These signal molecules modulate brain activity directly. The composition of the microbiome may well be related to the development of chronic pain. This fascinating idea is the subject of much ongoing research.

Suffering

Suffering is defined as an anguishing experience, severely affecting a person at a psychophysical and existential level. People who suffer may experience fear, anger, frustration, anxiety and depression. It is important to remember that pain and suffering are different, have different pathways and go to different structures in the brain.

Catastrophizing

  • Tendency to magnify the threat of pain
  • Feeling helpless
  • Ruminating about pain

Catastrophizing can be caused by chronic pain, but people who tend to catastrophize about other things in life are more likely to develop chronic pain. Catastrophizing magnifies the suffering from chronic pain.

Treatment of Chronic Pain

People with chronic pain often get on a specialist treadmill, hoping to find a cause and a cure for their chronic pain. While occasionally a cause can be found that eliminates the pain, that is the exception rather than the rule. At present there are no really effective treatments for chronic pain. There are treatments that decrease the intensity of the pain and particularly that decrease suffering from chronic pain. For most people, the quest to eliminate chronic pain is unfortunately a fool’s errand. The first step toward having a good life despite the chronic pain is often to give up hope for a cure. I will discuss current treatments and potential side effects below. I will start with pharmacological treatments (medicines) and then go over other kinds of treatment, which may actually be more safe and effective than medicines. I will describe the pathways affected by each treatment

Opiates

Opiates, like morphine and oxycodone work in all three pain pathways. They increase the descending pain inhibitory pathway and decrease transmission through the lateral and medial pathways. Unfortunately, there is good evidence that long term use of opiates in chronic pain increase sensitivity to pain an effect called hyperalgesia. This leads to increasing doses to get the same relief. Opiates stimulate reward centers in the brain and are thus very addictive. They also depress the respiratory centers in the brain. Overdoses of opiates cause death by stopping breathing altogether. Opiates are too dangerous to use for chronic pain, and over the long term make the pain worse.

Treatments that activate the descending pain inhibitory pathway

Serotonin and Noradrenalin Re-uptake Inhibitors

These are the most common antidepressants in use today. The one that seems to work best for chronic pain is duloxetine (trade name Cymbalta). These medicines work on the descending pain inhibitory pathway. They do not help everyone with chronic pain, but some people get significant relief.

NSAIDS

The most common NSAIDs like ibuprofen and naproxen work primarily by activating the descending inhibitory pathway. Other NSAIDS that are called selective COX2 inhibitors work primarily in other pathways.

Exercise Therapy

Certain types of exercise, particularly Tai Chi, Baduanjin (a form of Chinese qigong) and stationary cycling activate the descending pain inhibitory pathway.

Acupuncture

Acupuncture blocks pain by activating the descending pain inhibitory system. This has been shown in both animal and human studies.

Brain Stimulation

This can be done non-invasively using a helmet that uses magnetic stimulation, or in intractable neuropathic pain it is sometimes done by electrodes implanted on the motor cortex. This activates the descending pain inhibitory pathway. Obviously implantation of electrodes in the brain is invasive and it does not alway give lasting relief.

Treatments that modulate the medial (suffering) pathway

Pain Killers

Acetaminophen (Tylenol) works primarily on the medial pathway. The same is true for specific Cox2 inhibitor NSAIDS such as celecoxib (Celebrex) and the injectable parecoxib. These NSAIDs also work on the lateral pathway.

Oxytocin

There is some evidence that an oxytocin nasal spray directly modulates the medial pathway. Clinical trials are underway to see if it helps chronic pain.

Mindfulness Meditation

There is increasing evidence that mindfulness meditation relieves suffering from chronic pain by directly affecting the medial pathway. It reduces or eliminates catastrophizing, which as I noted above magnifies suffering. There is also some evidence that meditation affects the lateral pathway as well, and sometimes (but not always) reduces the intensity of the pain. This approach was pioneered by Jon Kabat-Zinn in his Mindfulness Based Stress Reduction clinic in Worcester, Massachusetts. This approach is described in a very approachable way in his book, Full Catastrophe Living.

Treatments that modulate the lateral pathway

Aspirin

Aspirin at a 1000 mg dose modulates the lateral pathway, thus reducing the intensity of chronic pain

Gabapentin

Gabapentin, which was originally developed as a seizure medicine also reduces chronic pain via the lateral pathway to the somatosensory cortex. It does not work for everyone, and has some addiction potential.

Yoga

There is good evidence that yoga decreases the intensity of chronic pain by modulating the lateral pathway to the somatosensory cortex.

Acupuncture

It turns out that people with chronic pain get a double benefit from acupuncture. Acupuncture modulates the lateral pathway as well as the medial pathway.

Brain and spinal cord stimulation

These are invasive methods that are only used in the most intractable cases. They don’t always work.

The Bottom Line

Chronic pain is a different animal from acute pain. Sometimes acute pain transforms to chronic pain, but chronic pain can also occur without any preceding injury. It affects different parts of the brain than acute pain, primarily the emotional and learning centers in the brain. Chronic pain may be a reward driven maladaptive learning process. There are no effective treatments to eliminate chronic pain, but it is possible to reduce suffering from chronic pain and sometimes decrease the intensity. Although medicines are sometimes somewhat helpful, they all have troublesome side effects. Non-medicine treatments like exercise therapy, acupuncture, mindfulness meditation and yoga have minimal to no side effects and can reduce suffering from chronic pain and sometimes decrease the intensity of the pain as well.

Further Reading

An excellent book written in non-technical language is The Song of Our Scars. It was written by a cardiologist who experienced severe chronic back pain.

Most of the information in this post came from an excellent review article: The Anatomy of Pain and Suffering in the Brain and its Clinical Implications. It is very technical and not for the faint hearted but for those of you with a science background, it is definitely worth reading.

Pain

The experience of pain is essential to humans. We live in a dangerous world and there are lots of things that can hurt us or kill us. The experience of pain warns our body-mind that damage is about to occur (or is occurring) and we immediately withdraw from whatever is causing the pain if we can. Almost all of this occurs at an unconscious level although there is definitely a conscious component to pain also. When we are injured pain forces us to rest the injured part until healing takes place. Once we have healed from the injury the pain goes away. It usually only lasts a few weeks at most.

People who can’t feel pain

To understand how important pain is to our survival, it is helpful to look at what happens when people are insensitive to pain. There is a rare condition called congenital insensitivity to pain. People who have this condition are able to feel touch normally, but are not able to feel pain at all. They sustain multiple injuries and rarely live past the age of 25. People with diabetes sometimes develop numbness in the feet and hands, called diabetic peripheral neuropathy. They are thus unable to feel pain in their feet. This leads to injuries and/or infections that they do not notice. It is common for diabetics with peripheral neuropathy to have amputations of toes or even feet because they can’t feel pain. Leprosy causes damage to skin nerves thus causing inability to feel pain. All of the deformities of leprosy are caused by injuries that are not painful to people with leprosy because their skin nerves are damaged.

Acute Pain

The kind of pain that both helps to keep us from being injured and helps us heal is called acute pain. There is another kind of pain that does not help us at all called chronic pain. More about chronic pain in the next post.

Pain Receptors

Humans (as well as other mammals) have four kinds of special pain receptors (nociceptors) in the skin. They only respond to damaging or potentially damaging input. There are mechanical nociceptors, which respond to pinching or pressure. There are temperature nociceptors that only respond to excessive heat. There are other temperature nocireceptors that only respond to excessive cold. Finally there are chemo nociceptors that respond only to damaging or potentially damaging chemicals.

There are also pain receptors in the intestines and the internal organs, mostly in the covering of those organs (called the peritoneum in the abdomen and the pleura in the lungs). These are much more difficult to study and not much is known about them other than that they are there and cause pain that is not very well localized.

Pain Pathways

There are three main pathways for pain in the nervous system:

  • Lateral pathway. This pathway goes from the nociceptors through a structure called the thalamus and then directly to the somatosensory cortex. The somatosensory cortex is located in the side of the brain called the parietal area and contains a map of the whole body. Sensations on the right side of the body connect to the left somatosensory cortex and sensations on the left side of the body connect to the right somatosensory cortex. This reverse order is because all the motor and sensory nerves from the spinal cord cross in the lower part of the brain called the brainstem and connect to the opposite side of the brain. The lateral pain pathway tells us exactly where the pain is coming from , how intense it is, and also the character of the pain (stabbing, pinching, hot, cold, etc).
  • Medial pathway. This pathway goes from the nociceptors to the thalamus and then to a part of the brain called the limbic system. This is the pathway to the emotion center of the brain. Pain thus causes an emotional response and lets us know how unpleasant the pain is. This pathway is where suffering starts to happen.
  • Inhibitory pathway. This pathway goes from a structure called the amygdala in the brain down to the spinal cord and blocks some of the pain from the other two pathways. This pathway works by releasing endorphins that attach to our opioid receptors. That is why synthetic opioids like morphine help relieve acute pain. They don’t work very well for chronic pain, as we shall see later.

Because of these three different pathways it is possible to feel pain without suffering and to experience suffering without pain. When these three pathways are balanced, we feel acute pain when we should, we find the experience unpleasant, and the pain goes away when we don’t need it anymore. When they are unbalanced, we can experience chronic pain, that is pain that persists beyond when it useful to the body-mind.

Pain and Memory

The experience of severe pain is also perceived in the hippocampus, which is in the temporal lobes of the brain and where memories are created and sent to other areas of the brain for storage. Pain creates instant and strong memories, so that humans and other animals can avoid situations that led to the pain. If you touch the metal handle of a hot frying pan, the memory of that pain ensures that you will use a hot pad from then on!

Bottom Line

Pain is essential to our survival as a species. As a result we and other animals have developed special sensors (nociceptors) that detect input that could damage our bodies or are damaging our bodies. There are two pathways through which the nociceptors send their messages to the brain, the lateral and the medial pathways. The lateral pathway goes to the sensorimotor cortex and allows us to feel the location, intensity and character of the pain. The medial pathway connects to our emotions and lets us know how unpleasant the pain is. That pathway is also where suffering occurs. The descending inhibitory pathway reduces our experience of pain both when getting away is the priority (think soldiers with war wounds who don’t feel pain until later) or when we have healed and don’t need the pain anymore. Chronic pain happens when these three pathways are out of balance. More on chronic pain in the next post.