You may be worried about muscle knots if you’re experiencing muscle pain, tenderness, or stiffness. An MRI scan can detect signs that suggest muscle knots are present, making your treatment more specific and effective. We’ll guide you through how an MRI scan works to identify damage caused by muscle knots and how it can be used on different areas of the body.
What are Muscle Knots?
Muscle knots, or myofascial trigger points (MTrPs), are a common source of musculoskeletal pain. They are tight and sensitive spots within your muscles that cause pain or discomfort. They happen when the muscle fibers become tense and contract. If the fibers stay contracted, it creates stiff, rope-like bands in the muscle.
Muscle knots can cause aches and pains in specific areas of your body, like the shoulders, neck, or back. They may feel swollen, tight, or bumpy, and they can also be sore to the touch. You may even notice inflammation at the site of the muscle knot.
While clinicians aren’t always exactly sure what causes muscle knots to appear in the first place, we do know that physical activity and tense muscles can make them worse. We also know that stress, poor posture, repetitive movements, and certain underlying medical conditions can also play a part by causing muscle fatigue and tension. Research has also found (2024) that certain proteins can cause muscle knots by contracting the muscles more. So they can be caused by physical, chemical, and psychological factors.
Will Muscle Knots Show on an MRI?
Magnetic resonance imaging (MRI) is well known for offering detailed pictures of soft tissue, making it one of the best ways to look at muscle injuries. However, while MRI will allow your clinician to identify swelling caused by the knot, it can’t always show the knots themselves. What it can do, though, is show the damage to the surrounding muscles and tissues as a result of the knot.
MRI results for muscle knots may show certain areas of the muscle around the knot's location that appear as hazy or cloudy areas. These areas are irregular in shape and brighter than the surrounding tissue due to swelling and inflammation caused by the knot itself. You may also notice areas where fluid has accumulated, which will result from an inflammatory response. This will also appear brighter compared to the surrounding tissue.
Muscle Knots MRI for Different Body Parts
MRI can detect changes in different muscles around the body, which may indicate the presence of knots. Here’s a rundown of which muscles may be affected in different parts of the body.
Back and Lumbar Region
MRI is useful for detecting the presence of knots in the muscles near the spine, which can often be linked to lower back pain.
Neck and Shoulders
The upper trapezius and sternocleidomastoid are two important muscles in the neck and shoulder region, and both can develop muscle knots. One study (2019) has also found that MRI can identify changes in the upper trapezius of migraine patients, suggesting a link between the knots and headaches. It can also help visualize the effects of muscle knots on joint function and stability, which is crucial for managing conditions like rotator cuff injuries.
Hips
MRI can identify issues such as tendonitis or joint problems in the hip flexors, hip abductors, and glutes. As well as showing damage and inflammation from muscle knots, it can help rule out other causes, narrowing your diagnosis to help you get better treatment.
Legs
The leg muscles, including the hamstrings, quadriceps, and calf muscles, can all be vulnerable to developing knots. An MRI can monitor blood flow to these muscles, identify any disruptions that may be caused by knots, and look for signs of inflammation and swelling.
Forearms and Hands
MRI is very effective at looking at swelling, fat buildup, and scarring in the muscles of the arms and hands, which can happen if muscle knots are present.
Diagnosing Muscle Knots
Your clinician will take a systematic approach to diagnosing muscle knots, starting with a complete medical history, physical examination, and other tests before you get to the stage of having an MRI.
Medical History
Your clinician will ask about your medical history and symptoms, including how long you’ve been experiencing discomfort or pain and any activities that make it better or worse. They’ll ask you about your physical activity, the kind of work you do, and any injuries or medical conditions you may have. This will help them to identify potential causes of any muscle knots.
Physical Exam
Your doctor will assess your posture, gait, and movement patterns. They may look for physical signs of inflammation or swelling in the affected area and rule out joint pain or pinched nerves with a physical examination.
Muscle Palpation
Palpation means using hands to feel and examine an area of the body. Your clinician will apply pressure to the affected areas of your body so they can identify areas of tightness, swelling, or tenderness. This technique can often pinpoint muscle knots because they may feel like nodules or lumps under the skin.
Trigger Point Identification
Once your doctor has identified a possible muscle knot, they will use pressure on areas around it to identify trigger points. For example, pressure in the shoulders may trigger pain or discomfort to flare up in the neck or head area.
Range of Motion Test
Your clinician will ask you to perform simple movements to check how flexible and mobile your muscles are and to see if muscle knots impact or limit your range of motion. This will help them identify the right treatment options for you.
Referred Pain Check
Similar to the trigger point check, a doctor will use pressure on different muscles to see if pain shows up elsewhere in the body (referred pain), which is quite common in people with muscle knots. This helps them differentiate between different conditions that may be causing chronic pain.
MRI
Your doctor may recommend having an MRI scan if other forms of treatment aren’t helping or if they suspect another underlying condition is causing you pain and discomfort. While MRI doesn’t show muscle knots directly, it can highlight changes in the muscle tissue, like swelling or fat buildup, that might suggest the presence of knots. It can also help to rule out other problems, like tears or structural issues, that could be causing your symptoms.
Why an MRI Scan is a Good Option
An MRI scan is a valuable medical imaging technique for diagnosing muscle knots because it provides a detailed view of your body’s soft tissues, including your muscles and the surrounding structures. MRI can help identify any underlying issues, such as inflammation or damage, contributing to the muscle knots.
By revealing the depth and nature of the problem, an MRI allows for a more precise diagnosis, ensuring that your treatment plan is tailored specifically to your needs. This approach can help avoid unnecessary invasive procedures and generic treatments, leading to more effective management of your condition.
How an MRI Scan Detects Muscle Knots
MRI scans use strong magnetic fields and radio waves to produce detailed 3D images of muscles and other soft tissues. The magnets first align water molecules within your body and then use radio waves to disturb this alignment. As the molecules realign, they emit signals that the MRI machine detects, and a computer translates them into a highly detailed picture. It will continue to do this slice by slice until a clear and sharp image of your muscles, including areas where muscle knots may be present.
Find an MRI Scan for Muscle Knots
Dealing with muscle knots can be painful and frustrating, but an MRI can help you get the right treatment—whether that’s rehabilitation through physiotherapy, medication, or injections. If you’re not sure whether an MRI is the right scan for you, our expert clinician consultations will help you figure out the next steps so you can regain your mobility and relieve discomfort.
What are the Treatment Options for Muscle Knots?
When dealing with muscle knots, a range of effective treatment options can help alleviate pain and restore mobility.
Physical Therapy
Physical therapy can help relieve pain and restore mobility through specific exercises and hands-on techniques. You’ll have a personalized exercise plan that includes strengthening moves to improve your flexibility and reduce muscle tension.
Massage Therapy
Massage therapy can be very effective at relieving tension and increasing muscle relaxation. Deep tissue massage can help break down tight spots and boost blood flow, which can get rid of muscle knots.
Trigger Point Release
This involves applying pressure to specific areas in the muscle to relieve pain and tension. You can do it by hand or use massage tools like foam rollers or massage balls.
Stretching Exercises
Stretching exercises are important in managing muscle knots by improving flexibility and reducing stiffness. Regular stretching also boosts blood flow to the muscles, aiding recovery and lowering the chances of developing future knots.
Heat Therapy
Often recommended before stretching to make the movements more effective, heat therapy involves using heating pads or warm baths to relax and loosen the muscles, relieve pain, and boost blood circulation.
Cold Therapy
Cold therapy can help constrict blood vessels, reduce inflammation and swelling in affected areas, and offer temporary pain relief. It’s often recommended after intense physical activity to reduce muscle tension.
Dry Needling
This technique involves inserting thin needles into trigger points to stimulate a ‘twitch response,’ which can help release muscle tension. Research (2023) has shown that dry needling can reduce pain and improve function in people with myofascial pain syndrome. However, it should be carried out by a trained physical therapist or practitioner.
Trigger Point Injections
This treatment involves injecting anesthetics or corticosteroids directly into muscle knots. It can offer quick pain relief and help reduce inflammation, especially for stubborn muscle knots that haven't improved with other treatments.
Nonsteroidal Anti-inflammatory Drugs (NSAIDs)
NSAIDs, such as ibuprofen, can relieve pain temporarily and reduce inflammation related to muscle knots. But it’s important not to use them long-term or as your only form of treatment.
Electrical Stimulation (TENS)
Transcutaneous electrical nerve stimulation (TENS) is a non-invasive treatment that uses electrical impulses to help relieve pain. It can reduce muscle tension and increase feelings of relaxation, making it a helpful option for managing muscle knots.
Ultrasound Therapy
Ultrasound therapy uses sound waves to help heal tissues and reduce pain. By improving blood flow to the affected muscles, this technique can also speed up the healing process, so it’s often used alongside physical therapy.
Sources
Evans, V, et al. (2021). Potential Role of MRI Imaging for Myofascial Pain: A Scoping Review for the Clinicians and Theoretical Considerations. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8166277/
How to Treat and Prevent Muscle Knots. 2023. https://www.healthline.com/health/muscle-knots
Liu, L, et al. (2024). Platelet-derived Growth Factor Receptor-α Induces Contraction Knots and Inflammatory Pain–like Behavior in a Rat Model of Myofascial Trigger Points. https://pubs.asahq.org/anesthesiology/article/doi/10.1097/ALN.0000000000005167/141761/Platelet-derived-Growth-Factor-Receptor-Induces
Loosen Up Those Muscle Knots: Here’s How To Get Rid of Them. (2024). https://health.clevelandclinic.org/what-are-muscle-knots-and-how-do-i-get-rid-of-them
Margalef, R, et al. (2019). Experimental myofascial trigger point creation in rodents. https://journals.physiology.org/doi/full/10.1152/japplphysiol.00248.2018
Monclus, P, et al. (2023). Shock waves as treatment of mouse myofascial trigger points. https://onlinelibrary.wiley.com/doi/10.1111/papr.13237
Sollmann, N, et al. (2019). Quantitative magnetic resonance imaging of the upper trapezius muscles – assessment of myofascial trigger points in patients with migraine. https://thejournalofheadacheandpain.biomedcentral.com/articles/10.1186/s10194-019-0960-9
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