Myofascial pain syndrome

Myofascial pain syndrome (MPS), also known as chronic myofascial pain (CMP), is a syndrome characterized by chronic pain in multiple myofascial trigger points ("knots") and fascial (connective tissue) constrictions. It can appear in any body part. Symptoms of a myofascial trigger point include: focal point tenderness, reproduction of pain upon trigger point palpation, hardening of the muscle upon trigger point palpation, pseudo-weakness of the involved muscle, referred pain, and limited range of motion following approximately 5 seconds of sustained trigger point pressure.

The cause is believed to be muscle tension or spasms within the affected musculature. Diagnosis is based on the symptoms and possible sleep studies.

Treatment may include pain medication, physical therapy, mouth guards, and occasionally benzodiazepine. It is a relatively common cause of temporomandibular pain.