TRIGGER POINT INJECTIONS
injection (TPI) is used to treat extremely painful areas of muscle.
Normal muscle contracts and relaxes when it is active. A trigger
point is a knot or tight, ropy band of muscle that forms when muscle
fails to relax. The knot often can be felt under the skin and may twitch
involuntarily when touched (called a jump sign).
point can trap or irritate surrounding nerves and cause referred pain
pain felt in another part of the body. Scar tissue, loss of range of
motion, and weakness may develop over time.
TPI is used
to alleviate myofascial pain syndrome (chronic pain involving tissue
that surrounds muscle) that does not respond to other treatment,
although there is some debate over its effectiveness. Many muscle
groups, especially those in the arms, legs, lower back, and neck, are
treated by this method. TPI also can be used to treat
specialists such as an orthopedist, physiatrist, pain specialist, or
neurologist can administer TPI. Injections are given in the physician's
office and takes approximately 30 minutes. Before performing TPI, the
physician may give the patient a nerve block to prevent pain from needle
needle is inserted into the trigger point and a local anesthetic (e.g.,
lidocaine, procaine) with or without a corticosteroid is injected.
Injection of medication inactivates the trigger point and thus
alleviates pain. Sustained relief usually is achieved with a brief
course of treatment. The injection may cause a twitch or pain that lasts
a few seconds to a few minutes.
the anesthetic may last about an hour and a bruise may form at the
injection site. Pain can be relieved by alternately applying moist heat
and ice for a day or two. In most cases, stretching exercises and
physical therapy are performed following TPI.
should contact the physician if redness or swelling develops. There is
some risk for puncturing a lung or the membrane that surrounds the lung
(called the pleura), when a muscle near the ribcage receives a trigger