The intercostobrachial nerve (ICBN) is connected to the brachial plexus and innervates the axilla, medial arm and anterior chest wall. The brachial plexus is a group of nerves that originate in the neck and whose basic function is to move the arms. (plexus definition: a network of nerves or vessels in the body. an intricate network or web-like formation.)
It is well known that many breast cancer survivors have problems with mobility, strength and sensation in the arm of the affected side. Today, we are going to talk about the specific complaint of tingling, numbness, pain and loss of sensation in the armpit and the inner arm. Here is an image, lifted from the pdf whose link is in the references section, that illustrates perfectly the areas of skin that are innervated by the ICBN.
Intercostobrachial neuralgia, also known as Post-mastectomy Pain Syndrome (PMPS) is estimated to occur in about 33% of breast cancer survivors. I can’t find reference to whether these are 5-year remissions, or longer or shorter intervals, but 33% seems to be the agreed upon figure, and this is for PMPS that persists for longer than three months after the breast surgery. There are other nerves involved in PMPS, but it appears that the the ICBN is the main nerve affected in most cases. Thus, some people say it is more correct to refer to Intercostobrachial neuralgia. However, as that doesn’t exactly roll off the tongue, let’s stick to PMPS and try not to think about PMS (ouch!).
Surgery in the axilla is usually to remove lymph nodes, and these are deep to the ICBN. Here is an image of the technique that is used to remove lymph nodes. I lifted it from the medscape article that is cited in the references section. Radiation therapy (RT) tends to damage nerve tissue and promote the formation of fibrosis, is also a cause of the PMPS.
Here is a wonderfully concise description of the surgical reasons for PMPS:
“The most commonly cited theory of chronic postoperative pain in breast cancer patients is the intentional sacrificing of the intercostobrachial nerves. These sensory nerves exit through the muscles of the chest wall, and provide sensation predominantly to the shoulder and upper arm. Because these nerves usually run through the packet of lymph nodes in the armpit, they are commonly cut by the surgeon in the process of removing the lymph nodes.” (http://www.cancersupportivecare.com/surgerypain.html)
I tried to understand what a “lymph node packet” might be, as this isn’t a term that we use in MLD speak. I think that it is a surgical term for the bundle of lymph nodes that is excised. [An article unrelated to PMPS and ICBN contained this phrase “We prospectively assessed 61 pelvic lymph node dissection specimens (packets) in 14 consecutive patients undergoing radical cystectomy.” ]
As usual, when we use yoga therapy for breast cancer rehabilitation, we must respect limitations. Firstly, PMPS won’t be cured by practising yoga. But, it can be helped. Secondly, there is variability in the extent and severity of pain and impairment to range of motion. So, adopt a personalised approach and be patient. Use simple, slow movements with breath synchronisation to achieve optimum results. If you are a yoga teacher, you probably believe in prana. I certainly do, and no matter how scientific the tone of my posts, I will absolutely vouch for the healing effects of good prana circulation. So, when teaching, keep your students focused on the practice, not on the results. Also, use your own healing energy and direct it towards them. Wish them well. Ask for guidance and the blessing of whatever guiding energy you believe in.
Here are a few suggestions for sequences that you can integrate into your own practice and bring some flexibility and mobility to the chest and inner arm region. Note that all sequences mobilise the brachial plexus in general.