To accurately diagnose Chronic Myofascial Pain (CMP), a thorough history and physical evaluation are essential. The history should include a detailed pain history, including when and how the pain started, the exact location of the pain, what it feels like, which treatment modalities have been attempted (and their results), and any history of trauma, overuse, or concurrent illness. The patient should point to the exact location of the pain, rate the pain on a scale of 0 to 10, and review what makes the pain better or worse.

Exam

A thorough physical examination should be performed, with a focus on the area of pain and discomfort. The physician should start by observing the patient's movements and posture, looking for poor posture, muscle strain, pain that increases guarding, and increased pain in other muscle groups. Trigger points cause muscle shortening with secondary weakness and decreased range of motion; therefore, a complete musculoskeletal exam with strength testing and relevant neurological assessment is essential. Tension and spasm in muscle groups should be assessed.

Identification

To make identification of trigger points easier, the patient should be as relaxed as possible. Trigger points can be felt by palpating the muscles; trigger points will consist of tender, hard (or ropy) knots or nodules surrounded by what feels like normal muscle tissue. Once a trigger point has been found, the local twitch response may be elicited as muscle or skin twitching¹. Next, the patient should be evaluated for referred pain. Knowledge of reference zones is essential to the diagnosis.