What are Myofascial Trigger Points?
Myofascial Trigger Points (MTP’s) are small areas of over contracted muscle tissue, which result in shortening of the affected muscle and reduced range of motion in the muscle. This can result in lameness, pain or altered body posture and can lead to other muscles overworking and becoming sore. MTP’s are often intensely painful when gentle pressure is applied or the affected muscle is stretched.
How do they occur?
MTP’s can occur after a sudden over stretching injury to a muscle such as a fall in the park, or from chronic, repetitive types of exercise where the same muscles are used over and over again. They can also occur after a major accident or trauma, secondary to surgery or secondary to arthritic pain (ie the animal alters its’ gait and then overuses a muscle). Elderly patients with hip arthritis often have trigger points in their front legs due to shifting their body position forward to take pressure off sore joints.
How do we diagnose them?
MTP’s are often diagnosed when other causes of lameness such as arthritis and bone problems are ruled out, but MTP’s may also coexist with other diagnosed conditions causing lameness. In humans, they have been shown to cause chronic low-grade pain and depression. Females tend to be more susceptible to them as a general rule in the human literature, possibly due to the hormonal influences on muscle tone.
If lameness persists, and has not responded well to pain relief and x/rays have not shown any abnormalities, a Myofascial Trigger Point may be the cause.
Diagnosis of MTP’s is made upon a detailed gait exam, made from a distance to locate abnormalities in the movement and posture, and muscle function testing. Range of motion examinations, which look like stretches, are performed to test muscle function.
The MTP’s can usually be located in muscles by careful palpation. They are often intensely painful to palpate (even gently) and can result in animals vocalising, twitching, turning to look at the vet, or trying to bite the vet or push the hand away from the affected area. Very stoic animals may only show minimal reaction to palpation of MTP’s
How are they treated?
A gentle form of massage can help to relax the myofascial trigger point. It is often a little uncomfortable for the patient when the point is initially massaged. Releasing the muscle causes endorphins (the body’s own natural pain killers) to be released in the brain so as the treatment progresses it becomes less uncomfortable. All four legs and the back are usually examined as postural changes in one muscle can cause overload injuries to other muscles. Occasionally, acupuncture needles are used to release particularly painful points.
Physiotherapy at home is an important adjunct to treatment in the veterinary surgery. This involves using heat bags, massage and stretching.
The massage and stretches will be explained in detail by the veterinarian, but if you have trouble remembering what to do, please contact the clinic for a refresher course. Too much massage or too hard a massage can be just as detrimental to recovery as not enough. Over stretching the muscle can result in the trigger point reforming.
Exercise will be restricted to on lead exercise initially, and gradually increased over time. A good rule of thumb is that your pet should come back after exercise looking exactly the same as they did when they started (ie no lameness or altered body position). In some patients, this may only be 5 minutes of gentle lead walking. Repetitive movements and excessive exercise (such as the 3 hour walk/run) are to be avoided at all costs, until your vet can incorporate these into the rehabilitation process.