Fibromyalgia (FM) is a chronic condition characterized by widespread pain across the body, often accompanied by fatigue, sleep problems, and cognitive difficulties. Many people living with this pain experience localized, intensely tender spots that feel like hardened lumps in their muscles, commonly referred to as “muscle knots.” This leads to misunderstanding about whether FM is the direct cause of these localized areas of tightness. Clarifying the nature of these knots requires distinguishing FM from a separate, but highly related, pain disorder.
Defining Myofascial Trigger Points
The term “muscle knot” is the common name for a Myofascial Trigger Point (MTrP), a hyper-irritable spot located within a taut band of skeletal muscle. These manifestations of muscle contraction are palpable, feeling like a rope or nodule distinctly different from the surrounding tissue. MTrPs are not merely sore spots; when compressed, they elicit local tenderness or a characteristic referred pain that radiates to a distant, predictable area of the body.
Clinicians differentiate between two main types of trigger points based on their behavior. An active trigger point causes spontaneous pain and tenderness, often reproducing the patient’s familiar discomfort. In contrast, a latent trigger point does not cause pain unless pressed, though it restricts the muscle’s range of motion and causes weakness. Latent points can become active when the muscle is stressed or overused.
Fibromyalgia Versus Myofascial Pain Syndrome
Fibromyalgia does not directly generate myofascial trigger points; instead, these knots are the hallmark of Myofascial Pain Syndrome (MPS). FM is a disorder of pain processing centered in the nervous system, leading to heightened sensitivity to pain signals, known as central sensitization. The chronic pain in FM is widespread, affecting both sides of the body above and below the waist, and is often accompanied by non-muscular symptoms like irritable bowel syndrome and cognitive issues.
The localized tender spots historically used to aid in FM diagnosis are called “tender points.” These are areas of tenderness near joints but do not present as a palpable, taut band in the muscle. Tender points are simply areas of generalized tenderness, whereas trigger points are structural abnormalities within the muscle fibers. The pain associated with MPS is regional, localized to a specific area or quadrant of the body, such as the neck, shoulder, or lower back.
The confusion arises because FM and MPS frequently occur together; nearly a quarter of chronic myofascial pain patients also meet the criteria for FM. This high rate of comorbidity means a person diagnosed with FM may also have MPS, making it challenging to determine the exact source of their pain. In these overlapping cases, the muscle knots are a symptom of the co-existing MPS, not the core FM diagnosis. Treating the knots addresses the regional MPS component but will not resolve the systemic, widespread pain amplification associated with FM.
Targeted Relief for Muscle Knots
Because muscle knots are a physical manifestation of MPS, treatment focuses on localized interventions aimed at relaxing the affected muscle fibers.
Invasive Procedures
Invasive procedures like dry needling involve inserting a fine needle directly into the trigger point to elicit a local twitch response, which helps break up muscle tension. Trigger Point Injections (TPIs) are another localized approach, using a numbing agent like lidocaine or a steroid to interrupt the cycle of pain and contraction within the knot.
Non-Pharmacological Therapies
Non-pharmacological therapies are highly effective for managing the regional pain caused by MTrPs. Manual therapies, such as massage and specialized pressure release techniques, apply sustained pressure to the taut bands to relax the contracted muscle fibers. Physical therapists may incorporate gentle stretching and postural training to improve muscle function and reduce the likelihood of trigger point formation.
Applying heat therapy, such as a hot pack or a warm bath, helps relax tight muscles and relieve pain associated with the knots. Over-the-counter topical analgesics offer temporary, localized relief to the painful area. Although these targeted treatments relieve the specific pain and limited range of motion caused by the muscle knots, they do not alter the underlying central sensitization or the widespread body pain that defines fibromyalgia.