Why is Endometriosis Painful?
Some patient’s with endometriosis have pain. The theory is that patients who have endometriosis that is infiltrative in nature can stimulate nociceptors directly and stimulate the inflammatory cascade causing pain. While pain is often associated with endometriosis, the exact reason why endometriosis is painful is not always talked about.
Infiltrative endometriosis is considered a noxious stimuli, an event that is or can be damaging to the tissues in the body. Physiatrist, Dr. Allyson Shrikhande, describes the tissue damage that occurs from endometriosis as a trauma to the body. It causes the nervous system to be in an excitable state and also starts an inflammatory cascade.
Anesthesiologist, Dr. Gerard DeGregoris, compares the direct invasion of very sensitive structures by endometriosis and the ensuing inflammatory response to getting hit with a hammer. When you get hit with a hammer, inflammation, a complex biological response of tissues to harmful stimuli, occurs in the form of heat, redness, swelling and an uncomfortable sensation. When a trauma occurs to tissues in the body, there is a direct stimulation of nerve fibers called nociceptors. When these nerve fibers are stimulated they transmit a pain impulse to the brain. Dr. DeGregoris explains that we developed these pain filled inflammatory responses so that we can be aware that tissue damage has occurred in order to try and protect our bodies from harm.
Types of Pain
Dr. DeGregoris explains how there are two types of pain associated with endometriosis, nociceptor pain and neuropathic pain. Nociceptor pain is caused by the direct damage of tissue from endometriosis. The sensations associated with this type of pain are usually sharp, aching or throbbing pains. Neuropathic pain is another type of pain that endometriosis patients often experience. This pain can occur even after excision of the disease, as neuropathic pain can last even after inflammation and the direct trauma to the body is gone. The sensations associated with neuropathic pain are heavy, stabbing or burning feelings.
How does Endometriosis Excision Help Pain?
Endometriosis excision surgery by an expert doctor is considered the gold standard of treatment for patients suffering from the disease. Excision works to remove the disease, or the noxious stimuli, from the body. Dr. Shrikhande works with many endometriosis patients in her practice in New York City, “I have seen patient’s pre and post operatively, after a proper excision treatment. A proper excision surgery gets rid of the noxious stimuli and stops the persistent inflammatory response.”
It should be noted that some patients are told that a hysterectomy can cure their endometriosis. If the uterus and ovaries are removed, but if endometrial implants are left in the pelvis, these noxious stimuli will continue to cause pain in patients.
Reasons for Pain Post Excision
Unfortunately, some patients who have endometriosis excision, with even the most expert surgeon, may still experience pain. This can be devastating and confusing to patients. While persistent disease and adhesions from surgery are possible causes for pain that should be explored, there are also many other reasons endometriosis patients may experience pain after complete excision.
Patients need to assess whether or not they could have other common co-current conditions that cause pain. Adenomyosis, interstitial cystitis and pudendal neuralgia are examples of conditions which can be found in endometriosis patients that often mimic endometriosis pain.
In her practice, Dr. Shrikhande sees how pelvic floor muscles are intimately involved with the suffering endometriosis patients endure. Dr. Shrikhande explains to patients how muscles contract in a linear pattern, similar to the pattern of a railroad track. When a patient has a trigger point, the pattern is no longer linear and is in disarray. A trigger point is a palpable taut band of muscle. When you touch the trigger point you get a twitch response and you also may get a referred pain pattern. Physiatrists work in conjunction with pelvic floor therapists to identify trigger points and which muscles in the pelvic floor are causing pain.
Dr. Sallie Sarrel is a pelvic floor therapist that focuses on pelvic pain, “The cause of pelvic pain is multi-faceted. Even after disease has been removed pain may remain.” Dr. Sarrel talks about studies that demonstrate how endometriosis causes higher tone throughout the pelvic floor. High tone increases the likelihood of painful spasms. She also addresses how the average diagnostic delay of 8-10 years warps the body and adversely impacts the way the pelvic floor functions. The body forms reactive adaptations to the inflammation, peritoneal insults, adhesions and constant pain signals caused by endometriosis. Dr. Sarrel has found in her practice that surgery alone cannot always fix these adaptions.
A diagnostic delay and a delay in having complete excision of endometriosis can transform the acute pain patients experience to chronic pain. Dr. DeGregoris explains that when inflammation goes from acute to chronic, prostaglandins tend to be overproduced by tissue and an up regulation of estrogen then maintains chronic inflammation and chronic pain. Dr. Shrikhande discusses how chronic pain can cause allodynia, a condition in which a stimuli that is not usually painful, becomes painful. Chronic pain can also cause hyperalgesia, a condition in which patients experience stimuli as extremely painful that most others find mildly painful. Once pain moves from acute to chronic, this pain state gets stored in the brain and becomes the patients new normal.
Treatment Options for Pain
An Anesthesiologist Perspective: Dr. DeGregoris uses different medications to help both the nociceptor pain and the neuropathic pain that endometriosis patients feel. Most doctors treat patients who present with painful periods with different hormonal treatments, as well as over the counter pain medicines. Anti-inflammatory NSAIDs block the conversion and liberation of prostaglandins. Working within 1-2 hours, NSAIDS are well absorbed, but too many can cause gastrointestinal issues. Naproxen is also well absorbed but is easier on the stomach. Acetaminophen is the safest pain medication for those patients who are trying to conceive.
Dr. DeGregoris also recommends pain agents such as Gabapentin and Lyrica which can help patients with neuropathic pain. Side effects of the medications can include dizziness, sedation, clouded-thinking and weight gain. Giving patients tricyclic anti-depressants, in a dosage far below what is used to treat depression, can also be effective for pain with the occasional side effects of sedation, dry mouth and confusion. SNRI (Cymbalta) was also designed primarily as anti-depressant but has been found to decrease the amount of pain impulses that make it up to the brain. One possible risk of SNRI’s is that this medication can cause serotonin syndrome. SSRI’s are another class of medications that are used primarily as anti-depressants, but are also effective in treating chronic pain.
Opioids are often seen as a controversial drug to treat pain. Dr. DeGregoris believes that if opiates are used with the guidance of a physician, they can be used safely. He believes they are ideal for postsurgical pain and episodic pain. He stresses that opioids are not ideal for long term relief because the more a patient takes them, the less pain relief she will get from them. When you take opioids chronically, your body becomes less receptive to their benefits. There are also significant side effects to these drugs such as respiratory depression, hormonal imbalance, opioid induced constipation and urinary retention. For some patients who are having worsening pain after opiates, or pain that does not improve, it is worth a try to decrease the dose to see if pain decreases or remains the same.
A Physiatrist Perspective: Dr. Shrikhande uses many different techniques to help endometriosis patients reduce their pain. She finds muscle relaxers (oral or suppository) helpful for patients. For patients with pelvic floor pain, Dr. Shrikhande starts with a suppository made of combined valium and baclofen. She also utilizes ultrasound guided trigger point injections such as Lidocaine. Topical medications made by compounding pharmacies can be quite beneficial to treat patients. Mixtures using Gabapentin or Lyrica, mixed with lidocaine or baclofen or even a NSAID’s are quite helpful for patients. For patients with vulvodynia, mixing compounds in olive oil reduces irritation.
Dr. Shrikhande not only utilizes medications, but encourages patients to engage in cognitive behavioral therapy, guided imagery, meditation and lifestyle modification to reduce pain and inflammation. She encourages patients to go to acupuncture to help desensitize the nervous system. She feels that learning the proper breathing technique can relieve the pressure and pain caused by tensions in the pelvic floor and may be the fastest way to help. Dr. Shrikhande works hand in hand with pelvic floor physical therapists to help patients with their lingering pain after surgery.
A Pelvic Floor Therapist Perspective: Dr. Sallie Sarrel states that “Pain is the sign that something in our bodies is wrong. When you have endometriosis, you have been sending that signal for so many years that your brain has gotten simply overwhelmed. You need to send a different signal and you need to use something to send a different signal. Pelvic Physical Therapy is one of the things that can mediate that pain signal.” She stresses that therapists need to have advanced and specialized training beyond doctoral education to evaluate and treat dysfunction of the pelvic floor muscles. Pelvic floor therapists should teach patients postural re-education, muscle relaxation, education for bowel and bladder issues, strengthening exercises and how to use the body to empower oneself over pain. Treatment may include deep tissue massage, internal or external, mobilization, joint manipulation, soft tissue mobilization, sensory, motor and sympathetic and parasympathetic nerve re-training.
The Cause and Cure for Pain
Endometriosis is a complex disease to treat. While endometriosis excision surgery is the gold standard of treatment and does relieve a significant amount of pain, sometimes pain still lingers. There seems to be many reasons why patients are in pain and an equal amount of possible solutions to reduce pain. Dr. Shrikhande concludes by saying, “Pain is so complex. When managing pain, it is really important to draw in a multispecialty group and work in collaboration. So many different factors are involved in a patient’s perception of pain. Regulation of stress, nutrition, diet and exercise all play a strong role in a patient’s quality of life and the perception of their pain.”
These lectures were presented at the annual Endometriosis Foundation of America Patient Awareness Day. For more lectures and more information about the work the EFA does and how to support it go to www.Endofound.org.