Since how long is your armpit and shoulder blade pain?
Is there any specific point of tenderness?
Is there any redness or warmth or lump?
Do you have pain in neck and tingling numbness in arm?
Any significant past medical or surgical illness?
Your arm pit pain and shoulder blade pain can be due to two possibilities;
1) Pinched nerve in the neck; causing radiculopathy symptoms. These symptoms comes off and on (waxing-waning) and can be of varying intensity. Physical therapy, chiropractic manipulation, acupuncture, deep electrotherapy (iontophoresis, phonophoresis), mild massage, local analgesic creams and anti-inflammatory analgesics are beneficial.
2) Myofascial trigger points; This can be associated with degenerative disc disease in neck causing pinched nerves. Trigger points may develop after an initial injury to muscle fibers. This injury may be a noticeable traumatic event or repetitive microtrauma to the muscles. The trigger point causes pain and stress in the muscle or muscle fiber. Myofascial trigger point is a hyperirritable spot, usually within a taut band of skeletal muscle or in the muscle fascia which is painful on compression. The treatment is almost above as following;
1) passive stretching of the affected muscle after application of sprayed vapocoolant
2) physical therapy
3) deep electrotherapy; iontophoresis, phonophoresis, short wave diathermy, electrical stimulation
4) local analgesic patch / ointment / spray
5) anti-inflammatory analgesics; Ibuprofen (Motrin / Advil)
6) ischemic compression therapy; pressure on the points
8) steroid shots
Please feel free for your follow up questions.