This is very likelihood to be myofascial trigger point. 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. As the stress increases, the muscles become fatigued and more susceptible to activation of additional trigger points. When predisposing factors combine with a triggering stress event, activation of a trigger point occurs. 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 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
The arm pit sebaceous cyst is unlikely to be related to it.
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