Dry needling is a form of myofascial trigger point (MTrP) therapy, involving a sterile acupuncture needle being briefly inserted into a previously identified hyperirritable spot within a muscle (a trigger point). The aim of MTrP needling is to reduce tension within muscle fibres by stimulating oxygenation of the taut muscle fibres, improving blood circulation, and reducing inflammation using the pinprick action of the needle.
There are two forms of dry needling; intramuscular stimulation (IMS) and superficial dry needling (SDN). IMS is where the needle is inserted directly into the MTrP, triggering a contraction of the muscle fibres, called a local twitch response (LTR). Stimulating a LTR has been shown to reduce pain-inducing substances within the muscle, stimulate muscle regeneration and remodelling, and enhance the release of fascia-related adhesions. SDN is where the needle is inserted 3-4mm above the MTrP, causing a reflex analgesic mechanism via the brain and spinal cord.
Some, if any, post-treatment pain or discomfort is normal to experience 24-48 hours following dry needling, however, the expected improvement in symptoms has been reported to be between 30-50% following a single treatment session.