Dry Needling & Western Acupuncture

What is Dry Needling?

D

ry needling is a broad term used to differentiate “non-injection” needling from the practice of “injection needling” which utilises a hyperdermic syringe and usually involves the injection of an agent such as saline, local anaesthetic or corticosteroid into the tissue or specific anatomical structures. In contrast to this, dry needling utilises a solid, filament needle, as is used in the practice of acupuncture, and relies on the stimulation of specific reactions in the target tissue for its therapeutic effect.

The term dry needling is also used to differentiate the use of needling in a western physiological paradigm from the use of needling in an oriental paradigm which is referred to as acupuncture.

Why Dry Needle!?

Whilst we practice a number of different forms of Dry Needling, the easiest to explain is perhaps Trigger Point Dry Needling (TDN). When an injury occurs from repetitive use or acute trauma, inflammation will be produced from the damaged tissues. The damaged tissues will also go into a protective tension state or contracture to guard against further damage from utilizing the injured tissue. This contracture and inflammation inhibit microcirculation which limits both the oxygen rich blood reaching the injury and the waste products leaving the injury. The injury site becomes hypoxic (decreased in oxygen) which stimulates the body to produce fibroblasts, a cell that produces fibrosis or scar tissue. This fibrosis and scarring builds up around the muscles and tissues limiting the tissues ability to fully function (lengthen/shorten) and can also cause compression and irritation of nerves (such as carpal tunnel syndrome) – all of which inevitably lead to biomechanical disturbances in gait and function.

TDN uses a small, solid filament needle which is inserted in a contracted painful knotted muscle to create a local twitch reflex which is both diagnostic and therapeutic as it is the first step in breaking the pain cycle as research shows this will decrease muscle contraction, reduce chemical irritation, improve flexibility and decrease pain. When a needle is inserted into muscle it will also produce a controlled lesion and will cut between three to fifteen thousand individual muscle fibers. The body considers the needle as a foreign invader and will activate the immune system as a response. The cut muscle fibers also produce an inflammatory reaction that your body will respond to not just locally but all over the body to reduce inflammation systemically.

Mechanical Effects

  • Dry Needling may mechanically disrupt a dysfunctional motor end plate
  • Needling results in a Local Twitch Response (LTR)
  • The LTR results in an alteration to muscle fiber length as well as having an inhibitory effect on antagonistic muscles

Neurophysiological Effects

  • Baldry (2001) suggests that dry needling techniques stimulate A-nerve fibers (group III) for as long as 72 hours post needling
  • Prolonged stimulation of the sensory afferent A-fibers may activate the enkephalinergic inhibitory dorsal horn interneurons, which implies that dry needling causes opioid mediated pain suppression
  • Another possible mechanism of dry needling is the activation of descending inhibitory systems which would block noxious stimulus into the dorsal horn
  • The LTR may also utilize the excessive ACh in the tissue which previously was triggering increased firing of localized fibers

Chemical Effects

  • Studies by Shah and colleagues (2001) demonstrated increased levels of various chemicals at sensitized motor end plates such as: Bradykinin, Substance P and CGRP (regulator of Calcium and Phosphate balance). These chemicals were reduced immediately post a LTR.
  • CGRP enhances the release of ACh from nerve terminals, which results in increased ACh receptors at the neuromuscular junction
  • Needle penetration will cause micro-trauma and micro bleeding (localized inflammation) and hence the introduction of PDGF into the area to help promote healing

How Effective Is It?

Its just a tool. How good is a spanner at fixing a car? Depends on the problem and the technician using it. Dry Needling is a useful adjunct to physiologically stimulate healing or break the viscious cycles of overload. But if problems have been long standing sometimes direct mechanical treatment of a tissue is needed to break long term thickened fibrotic tissue or scarring. That is why we suggest Dry Needling is administered as part of a package of treatment, where other variables can be addressed at the same time for a result that can be greater than the sum of its individual treatment constituents.