Myofascial pain syndrome, a term applied to a hyperirritable locus with muscle spasms or its associated fascia, is characterized by referred pain from a trigger point in a specific pattern, characteristic in each muscle. Among the patients, complaining of shoulder pain. We have found many patients with this syndrome. Since the pain is referred from most myofascial trigger points, patients with this syndrome are frequently overlooked and misdiagnosed. The pain is in a specific pattern, characteristic of each muscle and increases by stretching the affected muscle or when the muscle contracts against resistance. The patients complained of motion pain, but there was no contracture in most cases. Infiltration of local anesthetics in trigger point is a useful diagnosis. This disease must be differentiated without fail when in consultation with a patient who complains of shoulder pain. The purpose of this report is to discuss the symptoms, differential diagnosis and treatment of this syndrome which causes shoulder pain. Myofascial pain syndrome of the following muscles are discussed: M. infraspinalis, M. supraspinalis, M. teres major and minor, M. subscaularis. M. triceps (long head), M. biceps brachii and M. pectoralis major.
