Dry Needling is a technique that uses a very thin needle that is pushed through the skin to stimulate a trigger point  with the goal of releasing/inactivating the trigger point and relieve pain. 
Trigger points are distinct spots in taut bands  of skeletal muscle that are easily irritated. Pain from a trigger point can be local or can refer in a pattern.  Many people wonder what the difference is between acupuncture and dry needling. The difference is in the history and it’s intended effects:
Traditional Chinese medicine birthed traditional acupuncture. Traditional acupuncture treats an energy in your body called Qi, focuses on restoring the flow of Qi, and includes concepts of yin/yang.  
Dry needling originated from Western medical acupuncture which relies heavily on evidence-based science like anatomy, physiology, and pathology.  Dry needling is used to treat musculoskeletal pain, including myofascial trigger point pain. 
Why was treatment done?
While trigger points don’t have a single factor for their pesky origin, they usually arise from muscle overuse (i.e., poor posture or repetitive motion), trauma (i.e., an acute injury to the muscle), or psychological stressors (i.e., lack of sleep, depression, anxiety). 
Dry needling takes advantage of mechanical pressure which essentially causes the collagen fibers to become polarized. When the collagen fibers become polarized, they cannot hold structure  ; so, tissue remodeling is triggered.  In short, the goals of dry needling are to reduce pain, inactivate trigger points and restore function.
Benefits of dry needling include: controlling pain  , reducing muscle tension   , increased range of motion, remodeling tissue  to function better and relaxing the patient  .
Since dry needling carries a low risk,  many patients do not experience any side effects following a dry needling session. Side effects with dry needling are most often mild. Dry needling side effects include:
Increase in pain. There is some discomfort with dry needling but it is short-lived. Since the needles being used are very small gauge, there is minimal pain with needle insertion. The twitch response may feel like a cramp in the muscle and lasts up to 30 seconds. Soreness post dry needling can last 24 to 48 hours and will usually self-resolve.
Bleeding or Bruising. occurs at the needle insertion point and affects approximately 10% of patients. Patients taking blood thinners or with blood vessel problems tend to experience it more.
Fainting. is likely due to being dehydrated, patients that haven’t eaten before their appointment, or low blood pressure.
Fatigue or Tiredness. is part of the healing process and usually is an indication treatment is working.
Skin Reactions. are due to an allergic reaction to the metal the needle is made with. It can be identified by small red spots on the skin.
Adverse reactions to dry needling are rare, but include:
Pneumothorax. or a collapsed lung is caused by improper needle insertion over the lung field
Nerve injury. Neurapraxia is when the myelin sheath is damaged. Typically, will resolve within a few weeks or months. 
Axonotmesis is when the nerve itself has been damaged, prognosis is dependent upon the area and ranges from good to poor. 
Dry Needling isn’t for everyone. Your doctor might caution against dry needling if:
history of seizures that were induced with medical procedures
How you prepare
No special preparations are usually needed for dry needling therapy.
Food and medications
You don’t need to restrict your diet or avoid particular activities in preparation for dry needling, but it is important to eat before.
Clothing and personal items
Wear loose, comfortable clothing.
What to expect/How is the treatments administered?
Trigger points are located through examination and by feeling the muscles to locate the area of pain.
Depending on the area being treated, patients are either sitting or lying down. Needles are inserted to various depths depending on where the trigger point is located.
Filiform needles are used during dry needling. Filiform needles are so thin, patient’s often do not feel them being inserted.
There may be mild discomfort when the needle activates the twitch response that feels like a mild ache.
Needles may be manipulated in a variety of ways including but not limited to: a gentle in and out technique, a twisting technique or the needles may be attached to a TENS unit.
Typically, needles are left in place for up to 20 minutes before they are painlessly removed.
Before the procedure
During the initial visit, your chiropractor will ask questions about your problem and do an exam. The goals of the evaluation include:
Diagnosis of the problem
Identify anything that would be a contraindication to care
Your chiropractor may also recommend additional tests such as X-rays or an MRI. Specific tests/procedures you may undergo include:
Range of motion testing
Imaging studies such as x-ray
A general health exam
After the exam, your chiropractor will give you a diagnosis, discuss treatment options, answer any questions you may have, or refer you out to another healthcare provider. The initial visit is the longest due to the need for examination. Subsequent visits are much shorter.
How you prepare
There is no special preparation needed before a chiropractic adjustment; however, attire can be important. While you can be treated in a variety of different clothing styles, there are some general guidelines. If you are getting soft tissue work done, the area of treatment should be easily accessible. General tips for what to wear include: Clothes that are loose fitting, Sneakers or flats, thin/stretchy fabric (leggings, yoga pants), sweatpants, gym shorts, shorts or pants. If possible, try to avoid wearing: tight clothing, dresses or skirts, high heels, pantyhose or shape-wear, work boots, jewelry, a suit jacket or tie, tight belts, layered, bulky or delicate clothing. After your first few visits, you will get an idea of good attire. You will have to fill out intake paperwork and you’ll need to schedule an evaluation.
What to expect/How is the treatments administered?
During cold laser therapy, the practitioner applies a laser device that outputs different wavelengths  and energy levels of light directly to the problematic area. The cells in the area absorb the light and energy and promotes healing.
Treatment in one region takes about 5-15 minutes.
After a treatment
After dry needling, mild soreness in the area treated is normal. There can be immediate soreness, or it can develop the next day. Patients may also feel tired, or sleepy, this is also a normal response and typically lasts a few hours. To ease pain and soreness after dry needling, patients should Increase water intake and apply ice to the area as needed. Patients should be able to return to normal activities immediately after dry needling.
Contact the office or your doctor if you:
Have shortness of breath or a dry persistent cough following dry needling.
Results/treatment success rates
Research suggests dry needling works better than sham (fake) needling  as well as effectiveness being confirmed many studies including 2 systematic reviews.
 A 2005 review of randomized controlled trials concluded that dry needling may provide relief for low back pain. 
Many patients have improved mobility and decreased pain immediately; however, typically, it takes 2-3 dry needling sessions before results are seen.
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