We get a lot of questions about Dry Needling and the next few blogs will address several theories that support the treatment. There is currently a good amount of medical literature supporting Dry Needling and this is great, but the theories behind Dry Needling are fascinating and interesting to discuss.
The 4 models are as following:
1. The Radiculopathy Model
2. The Trigger Point Model
3. The Spinal Segmental Sensitization and Pentad Model
4. The Central Model
Each of the next 4 blogs (including this one) will discuss one of these theories as it relates to Dry Needling. We hope this gives you a better understanding as to why Dry Needling works so well. We are aware that the models tend to use medical terminology and can be a little hard to follow, so we will try to explain things as we go to make the explanations easier to understand.
The Radiculopathy Model
This model, proposed by C.C. Gunn, states that the myofascial pain syndromes (MPS) are always the result of peripheral neuropathy. He defines peripheral neuropathy as ‘a condition that causes disordered function in the peripheral nerve’. (The peripheral nerve exists after the nerve leaves the spinal column). Gunn considers spondylosis, or bony/spur formation, as the most likely cause. He also discusses how the deep spinal tissues and muscles, such as the multifidi, can lead to disc compression or intervertebral foramina (hole where nerve comes out from spinal cord) compression and irritation. This irritation causes nerve irritation, and this causes neuropathy….thus supporting his model.
Simply stated, Gunn believes that Tender Points and Trigger Points in your body are a result of spinal nerve dysfunction and many times are not as a result of a problem at the local level. This model parallels a lot of what is taught to chiropractic students as the neurological system affects all functions of the body. Sensitized nerves lead to soft tissue compromise. After all, it’s the nerves that determine the health of your body and the nerves start at the spinal cord. Striated muscle, which accounts for 40 percent of our total body mass, is then adversely impacted by impaired neurological function, and this leads to tender, dysfunctional soft tissue.
Due to these facts, Gunn’s treatment is aimed at the musculo-tendinous (where muscle becomes tendon) junction, or the location of the muscle motor points, because this is where the muscle is most likely innervated by the nerves. So, he does treat the area where he identifies Tender Points/Trigger Points. In addition, the spinal level associated with this region must be treated as the small local nerves, which innervate the multifidi and other associated spinal structures, will have pathology that needs to be addressed. It is important to note that unless the proximal spinal level is treated (assuming there is dysfunction at the spinal level), the distal component will not resolve. To better understand this, it is important to point out that the nerves in the paraspinal muscles as well as at the associated distal locations are linked…this is why it is necessary to treat both.
Another important concept of the Gunn model is that relatively minor musculoskeletal injuries will not result in long lasting issues unless the associated nerve root is involved or otherwise damaged. With this concept, he again demonstrates that the spinal component controls what goes on distally.