If your lower back pain is muscle-related, your doctor may suggest a trigger point injection. Myofascial trigger points are felt to be hyper-irritable foci (points) in muscles and fascia (connective tissue) associated with taut muscle bands. Trigger points are diagnosed by palpation (ie, feel) and produce a local twitch response and a referred pain pattern distal to the site of muscle irritability.
The trigger point injection should be carried out under antiseptic technique. There is little evidence to support any beneficial effect of adding corticosteroid to the injection. In fact, a saline injection can as effective as a local anesthetic. However, for patient comfort and to assist in deciding upon therapeutic efficacy, injecting a local anesthetic such as lidocaine and/or mepivacaine is acceptable.
