15 Fu’s subcutaneous needling
Fu’s subcutaneous needling (FSN) is a therapeutic approach for musculoskeletal painful disorders that originated from traditional acupuncture. This procedure is performed by inserting a special trocar needle into the subcutaneous layer around the afflicted spot to achieve the desired effect (Figure 15.1).
The name FSN, or Fu Zhen (, in simplified Chinese; , in Traditional Chinese), has some profound implications. ‘Fu Zhen’ is the Chinese pronunciation for FSN. Fu is the surname of the inventor, who is also the first author of this chapter. In Chinese, ‘Fu, ’ means floating, and it could also mean superficial. ‘Zhen’ means acupuncture or needling. Therefore, in some English-language papers, FSN is also called Floating Acupuncture (Huang et al. 1998), Fu’s Acupuncture (Zhang 2004), Fu Needling (Xia & Huang 2004) and Floating Needling (Fu & Huang 1999). However, neither floating nor superficial are precise translations; the word subcutaneous is a better substitute in terms of demonstrating the manipulation features of FSN.
Although FSN originated from classic acupuncture, FSN’s manipulation and theory have nothing to do with the concepts of traditional acupuncture, such as meridians, acupoints, Yin-Yang, and Qi. Therefore, FSN is not some variety of acupuncture and should not be referred to as acupuncture. Figure 15.2 shows the FSN needle in a subcutaneous layer of a human cadaver.
Another approach, called intradermal needle therapy, is easily confused with FSN. The intradermal needle (Figure 15.3) is a type of short needle made of stainless steel wire, especially used for embedding in the skin (Cheng 1987) rather than in the subcutaneous layer.
The term ‘Fu’s subcutaneous needling’ was first mentioned in a 2005 article by Fu and Xu, in which they described the treatment method (Fu & Xu 2005), followed by several other research papers (Fu et al. 2006; Fu et al. 2007). FSN should be clearly distinguished dry needling, which involves the insertion of a fine single-use sterile needle into a trigger point (TrP) for the treatment of myofascial pain. Dry needling has been in use since the 1970s and differs from the use of needling from an Oriental paradigm (Baldry 1995, 2000, 2002, Chu 1995, Hsieh et al. 2007, Hong 2000, 2002, 2004, 2006, Simons 2004, 2008). TrP dry needling is based on a Western anatomical and neurophysiological paradigm and has been increasingly utilized in the Western world, especially in the US, UK, The Netherlands, Canada, Belgium, Norway, Australia, Switzerland, Ireland, Brazil, South Africa and Spain, among others (Dommerholt 2006). Unlike traditional acupuncture, dry needling does not consider ancient Chinese philosophy and traditional ideas. Traditional acupuncture is based on pre-scientific ideas, such as meridians, Qi (a kind of invisible energy) and Yin-Yang (Ellis et al. 1991, White & Ernst 2001, Kim 2004), whereas dry needling is entirely based on the recent understanding of scientific neurophysiology, anatomy, and pain sciences (Ghia et al. 1976, Melzack et al. 1977, Melzack 1981). The manipulation method used in acupuncture differs from that used in dry needling and is based on different theoretical foundations and principles.
Contemporary research and the emergence of dry needling have reduced the sense of mystique surrounding non-injection therapies for pain (Amaro 2008). Although acupuncture and dry needling have different theoretical bases, they are similar in some aspects:
Further, in trigger point dry needling the importance of the local twitch response is emphasized, which is a reaction during needling with some resemblance to the ‘De-Qi’ effect in acupuncture (Hong 1994). Chou et al. (2008, 2009) have modified the technique used in acupuncture into a procedure similar to Hong’s dry needling technique. Therefore, in a ‘broad sense’ acupuncture can be considered as one type of dry needling.
FSN borrowed some ideas from traditional acupuncture, but its essential features are different from those of traditional acupuncture. Acupuncture and FSN are based on different theories and different techniques and manipulations are employed with entirely different kinds of needles. Traditional acupuncture theory is mystical, even to Chinese doctors. FSN is a much easier approach, which does not consider the traditional theories. Compared with the current practice of dry needling, FSN has several unique features. There are at least two differences between FSN and dry needling. FSN needles are inserted into non-diseased areas and FSN is confined to subcutaneous layers, whereas dry needling inserts the needles into TrPs and often deep into the muscles.
De-Qi or Qi (Cheng 1987) is an acupuncture phenomenon that occurs during needle manipulation, experienced by the patient as a particular sensation, e.g. soreness, aching, numbness, or ‘needle grasp,’ or by the acupuncturist as a pulling sensation (Li, 199, Langevin et al. 2006, White et al. 2008). Traditionally, De-Qi must be achieved in the process of acupuncture regardless of the manipulation used; otherwise, the therapeutic results are poor (Cheng 1987). In every textbook on acupuncture in Chinese, the importance of De-Qi is always emphasized and reiterated and acupuncturists repeatedly highlight De-Qi. As a result, most Chinese patients believe in the adage, ‘no De-Qi, no effect.’ Sometimes, patients will be disappointed in the acupuncturist if they fail to acquire De-Qi, even though it may cause discomfort to the patient.
Acupuncturists and patients are not the only ones who consider De-Qi to be pivotal. Some scientists also believe that De-Qi plays an important role in acupuncture analgesia (Cao 2002, Park et al. 2002). Acupuncture needling may activate afferent fibers of peripheral nerves to elicit De-Qi, the signal of which ascends to the brain, activates the anti-nociceptive system, including certain brain nuclei, modulators (opioid peptides) and neurotransmitters, and through the descending inhibitory pathway results in analgesia (Cao 2002).
However, occasionally acupuncture does work without De-Qi and could fail even when the patients achieve strong De-Qi. Furthermore, many acupuncture substitutes, such as cupping, moxibustion, transcutaneous electrical nerve stimulation (TENS), and so on, do not elicit De-Qi, but they appear to be effective nevertheless (Chen & Yu 2003).
Therefore, De-Qi may be not as relevant as traditionally is often suggested. To prove the insignificance of De-Qi, the best method is to stimulate the tissue without obvious direction and then observe what will happen. The elicitation of De-Qi is related to the needling depth (Lin 1997). There are few free nerve endings and proprioceptive receptors in the subcutaneous layer, whereas free nerve endings are abundant in the epidermis and dermis. Proprioceptive receptors do exist in the muscular layer (Tortora 1989). Therefore, there should be no occurrence of De-Qi even if the subcutaneous layer is stimulated. Under such a condition, does the needling effect still exist? For an acupuncturist, it is easy to verify the existence of the needling effect, and this simple trial was one of several factors resulting in the discovery and development of FSN. One example of a form of acupuncture where achieving De-Qi has been shown to not be critical is wrist-ankle acupuncture.
Wrist-ankle acupuncture (WAA) (Jiang et al. 2006) is also called wrist-ankle needling (Song & Wang 1985). Dr Xinshu Zhang, a neurologist who has worked at the Second Military Medical University in Shanghai, developed WAA in 1972. WAA divides the whole body into 12 longitudinal regions, six for each half of the body (Figure 15.4).
There are 6 points 2 cun (about 50 mm) above the wrist joint corresponding to the 6 regions above the diaphragm, and there are 6 points 3 cun (about 75 mm) above the ankle joint corresponding to the other 6 regions (Figure 15.5). A cun is a measure of distance relative to a person’s body dimensions commonly used in traditional Chinese medicine. If a disorder occurs in one of the regions, the corresponding point should be chosen. Unlike conventional acupuncture, WAA inserts an acupuncture needle only superficially in the subcutaneous layer; some authors claim that WAA is effective in the treatment of pain with various origins (Zhu & Wang 1998). Needling superficially in WAA wrist or ankle points to treat distant disorders often has a good effect (Song & Wang 1985, Chu & Bai 1997) leading to the idea that needling close to the afflicted area could be at least as effective as needling in an area remote from that which is afflicted, and that needling closer may be preferable. These thoughts motivated the principle author to seek answers through clinical trials.
The Medical Classic of the Yellow Emperor (also known as The Yellow Emperor’s Canon on Internal Medicine or The Yellow Emperor’s Inner Classic), written thousands of years ago, is a fundamental book of Traditional Chinese Medicine. The book states that needling superficially and needling nearby are two characteristics of the ancient techniques for the treatment of painful problems. The principle author of this chapter learned from and was inspired by these techniques in the process of developing FSN. In The Medical Classic of the Yellow Emperor, there is a chapter entitled ‘Guanzhen,’ which records 26 special techniques. The 26 techniques are classified into three groups: a 9-technique group, a 12-technique group, and a 5-technique group.
The characteristic of superficial needling refers to quite a few techniques, such as MAO Ci in the 9-technique group, Zhizhen Ci and FU Ci in the 12-technique group, and Ban Ci in the 5-technique group. Among them, especially Zhizhen Ci resembles FSN. Hold up the skin with the thumb and index fingers of the left hand; insert the filiform needle into the skin; and then go forward toward the painful spot obliquely. Zhizhen Ci can be said to be a precursor to FSN without FSN needling and its swaying movement.
Needling nearby is often seen in the 26 techniques, such as Fen Ci in the 9-technique group, Hui Ci, Qi Ci, Yang Ci, Duan Ci, and Pangzhen Ci in the 12-technique group, and Baowen Ci, Guan Ci, and Hegu Ci in the 5-technique group.
Aside from the practicable techniques mentioned above, The Medical Classic of the Yellow Emperor also describes many systemic theories, such as meridians, acupoints, and Yin–Yang. Nevertheless, from then on, most ancient acupuncture texts adopted meridians, acupoints and other theories instead of practicable techniques as their main interests. The long-term neglect of more practicable techniques resulted in today’s acupuncturists having little knowledge about this valuable ancient technique, which really is a precursor to FSN.
Based on the above ideas and thoughts, Fu devoted himself to seeking a new and effective treatment strategy and finally developed FSN in 1996, while he worked at the First Military Medical University in Guangzhou, China. The university ran a TCM Clinic in Zengcheng, a city near Guangzhou. In the clinic, patients who were in significant pain were more numerous than the author could deal with, which encouraged him to find ways to relieve the painful problems much more efficiently and quicker.
Fu attempted to treat a patient with tennis elbow or lateral epicondylitis by needling the patient near the painful spot, which caused a positive response, and as such became the first successful case of FSN. From then on, a series of clinical trials were completed and positive results were commonly achieved. In the same year, Fu wrote a brief introduction to FSN, which was published in a Chinese health newspaper (Fu 1996).The following year Fu published his first research paper in Chinese in the Journal of Clinical Acupuncture and Moxibustion (Fu 1997).
Fu continued using FSN in his clinics and accumulated more and more evidence, which improved the technique and clinical efficacy of FSN. The initial focus was on developing the FSN needle and on increasing the indications of FSN.
In physics, scientific theories usually precede technologies. However, in traditional medicine, technologies or therapies often precede theories. Without any past experience to draw from or previous theories to follow, Fu had to develop FSN by trial and error. During FSN’s early months, he used a filiform acupuncture needle, but over time several factors changed his thinking:
FSN needs a period of retention, and the patients could not stay in any settled position for extended periods of time. The patients should be able to move their bodies and limbs during needle retention. With a stainless-steel filiform needle patients easily can get hurt.
Fu realized that certain changes had to be made to the FSN needle; however, the challenge he faced was how to determine what kind of needle would go through the skin quickly and stay beneath the skin safely.
Initially, a physical method was developed: a needle was invented using a new material. The material was solid at low temperatures, and became soft at high temperature. When not in use, the needle was stored in a refrigerator to keep it solid. When FSN was used, the needle would become soft after insertion due to the patient’s body temperature. The concept was acceptable, but the material used for the needle and the refrigerators were too expensive for most acupuncturists.
Next, a chemical method was considered. Fu tried to produce a biological hard needle made of a high-polymer material, such as absorbable catgut, which would dissolve subsequently by tissue fluids. A large amount of time and energy were devoted to finding such a material, but none was found.
Finally, Fu invented a trocar needle, which is still used at this time. The FSN needle consists of two parts: a solid stainless-steel needle and its soft casing tube. The former is hard enough to break through the skin quickly and to ensure that the FSN needle can be easily controlled; the latter is soft enough to remain beneath the skin without continuously sticking the patient.
To determine whether a particular disorder would be a suitable indication for FSN, an immediate effect would need to occur with FSN, which was later referred to as ‘the golden criterion’. Disorders or symptoms for which FSN did not get immediate results were not included into the indications for FSN. After the first successful case, Fu continued searching for other FSN indications, a process which occurred in roughly four stages.
In the early months, FSN was used mainly for the treatment of patients with painful problems in the extremities, such as epicondylitis, stenosing tenosynovitis of the styloid process of the radius, snapping finger, osteoarthritis of the knee, sprain and strain of ankle, among others. Due to limited experience with FSN in those early days, the success rate of the treatment of painful problems of the extremities was only about 40%. Therefore, FSN was not considered for the treatment of complex diseases or diagnoses of the trunk.
In the autumn of 1998, the primary author saw a patient who was suffering from severe neck pain and who had been treated unsuccessfully in the university hospital for nearly 1 month. A friend of the author requested his assistance and pleaded whether something could be done for the patient, who happened to be her father-in-law, before leaving in a couple of days. The author had no better option for treatment than FSN. Surprisingly, the neck pain was immediately relieved, after which the author started using FSN to treat patients with non-visceral painful diseases in the trunk, such as low back pain with or without sciatica, cervical syndrome, and mild ankylosing spondylitis.
FSN is performed superficially; hence, superficial illnesses such as soft tissue injuries were regarded as primary FSN indications. FSN was never expected to be used for the treatment of persons with visceral diseases, until an 80-year-old Chinese acupuncturist wrote the author that he had treated a patient with appendicitis using FSN. Although FSN may not always be suitable for the treatment of appendicitis for a variety of reasons, the letter implied that FSN may in fact be used in the treatment of persons with visceral diseases. From then on, FSN was used to treat individual with acute and chronic gastritis, cholecystitis, pain due to urinary calculus and painful menstruation, among others.
After the successful treatments of patients with visceral diseases, more confidence in FSN was gained. The primary author moved on to treat patients with painful head and face problems. The experiences convincingly showed that FSN is effective for the treatment of localized headaches and for painful problems of the face caused by temporomandibular pain and dysfunction and accessory sinusitis. FSN was mainly used to deal with painful problems where an immediate response could always be achieved. The question was raised whether FSN could effectively manage non-painful diseases. After many years of practice, it was found that FSN can also deal with non-painful problems. At present, several non-painful indications have been treated successfully, including chronic cough without sputum, onset of chronic asthma and localized numbness.
FSN needles, individually packaged and pre-sterilized with ethylene oxide gas, are designed for single use. The FSN needle is made up of three parts (Figure 15.7): a solid steel needle core (bottom), a soft casing tube (middle), and a protecting sheath (top).