Radiotherapy given to the head and neck areas can caused scarring effects in long term. So, it is of no surprise that patients can get "hardening" skin and muscles especially at the neck and jaw areas.
Hardening of the jaw areas caused trimus, a medical term describing the difficulty and inability to open the mouth fully. In a ordinary person, one can insert 3 fingers in a vertical position into the mouth. This equates to about 4-5cm of mouth opening. After radiotherapy, the temporo-mandibular joint that is the joint just underneath your ear level that acts to open the mouth can become stiff. This reduces the ability to open the mouth wide and in so doing, it can cause pain as well. The best way to stop this happening is doing periodical opening the mouth as wide as you can by inserting orange stick (ice cream stick ) into the mouth. One can put in about 10 stick stacked up together. Alternative is to use thick towel. Whatever you put into the mouth does not matter. You only need something for your front teeth to bite and grip and stretches the opening for the mouth. Chewing exercise in this case will help. Trimus can happen gradually and not immediately and hence it is good to practice some jaw and tongue exercises routinely. Come to our support group and we will show you how.
The other part of hardening is the neck muscles and patient complains of stiff neck and inability to turn in a full range of movements to look left and right. The only way to see right and left is to turn their whole body instead. Again, this can be prevented by doing routine neck exercises. The way to achieve this is to do the 6 range of movements of the neck - up and down, turn left and right and tilt left and right (ie tilt your ear to the left and right as compared to turning the neck). Try to turn until it is just a bit painful and use your hand to give it a bit more push actively to turn it more to overcome the resistance. Although this will generate a bit of initial pain, it will help to stretch the muscles more and this part is really the part that helps. As in any exercises, you need to feel a bit of muscle stress ie pain to get the benefit. But, do it in moderation. A little bit of pain and not severe pain.
The last thing you will need a a good moisturiser. The sweat gland is partially damaged by the radiotherapy is hence the skin will always tend to be more dry. Dry skin is not good and the skin feels hard. So, apply a generous amount of moisturiser - aqueous cream equivalent with Aloe Vera, Vitamin E, paraffin based are some examples. But, make sure the cream is free from perfume or only lightly scented as perfume is not good for radiotherapy damaged skin. Use it twice a day if possible.
All this will help you get a normal skin and minimized the hardening of jaw and neck muscles. Remember that prevention is better than treatment. Get it into routine so that you will never get this problem. If problem has already developed, a physiotherapist will be able to help.