This study was supported by a grant from the animal center of Chang Bing Show Chwan Memorial Hospital, Changhua, Taiwan. The authors would like to thank Show Chwan Memorial Hospital IRCAD TAIWAN for their invaluable support and assistance throughout this research project.

All procedures involving animal subjects were approved by the Institutional Animal Care and Use Committee (IACUC) of the Chang Bing Show Chwan Memorial Hospital, Changhua, Taiwan (111031) on October 2022 (Figure 1).
1. Preparation of animals
<ol>
	<li>Purchase 48 maleSprague-Dawley (SD) rats (age: 8-10 weeks, weight: 250-300 g).</li>
	<li>House rats individually in ventilated cages at 24 &#177; 2 &#176;C and a 12-h dark and light cycle.</li>
	<l...

Improving FSN Therapy in the Rat Model&amp;#58; Minimizing Discomfort and Maximizing Efficiency

This study observes the effect of FSN treatment on neuropathic pain in rat CCI models. This study presents a protocol for SFI and electrophysiological testing to evaluate the therapeutic effects after FSN or TENS treatment. Additionally, it illustrates how to evaluate the functional recovery of the injured nerve using noninvasive behavioral tests and physiological measurements. Results showed that the FSN treatment after CCI-induced sciatic nerve pain showed significantly better improvement in all prognostic indicators t...

Neuropathic pain, defined as pain caused by nerve damage, is estimated to affect 6.9%-10% of the world&#39;s population, and the reported lifetime prevalence is 49%-70%1,2. It is also considered to be one of the most difficult pain syndromes to manage. The use of pharmacological agents to manage neuropathic pain has yielded limited success as commonly prescribed pain medications like non-steroidal anti-inflammatory drugs and opioids have shown little efficacy in relieving this type of pain3,4. There is therefore a great need to explore new treatment options, especially non-pharmacological treatments. Acupuncture, as a non-pharmacological intervention, potentially alleviate neuropathic pain by exerting analgesic effects on the somatosensory system. Both clinical and preclinical studies have indicated that acupuncture is effective in relieving neuropathic pain symptoms without significant side effects5,6,7. However, the central mechanism of acupuncture treatment for pain relief in neuropathic pain remains to be further investigated.
In recent years, Fu&#39;s subcutaneous needling (FSN) has gained popularity for treating pain-related neurological disorders8. FSN originated from traditional Chinese acupuncture and was first described by traditional Chinese physician Zhonghua Fu in 19969,10. While originating from traditional acupuncture, FSN differs significantly in its techniques and theories from meridian-based acupuncture, yin and yang principles, and acupuncture point concepts. FSN places greater emphasis on neurophysiological and anatomical approaches to effectively address myofascial pain11. FSN therapy is applied in clinical practice to address various painful muscular disorders, targeting the connective tissues closely associated with the muscles, particularly focusing on the treatment of tightened muscles (TMs)12. As a complementary therapy for pain relief, there is also clinical evidence that FSN is effective in treating soft tissue injuries in addition to providing rapid pain management and significant improvement in soft tissue spasms13,14. FSN therapy involves specific techniques tailored to address the underlying myofascial trigger points (MTrPs) associated with the condition. The FSN needle insertion position is carefully chosen based on the location of these trigger points, allowing precise targeting of affected areas. During the procedure, the FSN needle is inserted into the subcutaneous layer, where it is intentionally stopped to optimize therapeutic effects. A distinctive technique known as the swaying movement is then employed, involving a gentle oscillating motion of the needle to stimulate the tissues and promote the therapeutic responses10. The development of MTrPs is associated with the energy crisis theory, which explains that factors such as chronic muscle overload, excessive exercise, improper exertional postures, muscle atrophy, and degeneration can contribute to the onset of muscle tissue ischemia and hypoxia. This oxygen and energy deficiency within the muscle tissue is believed to play a key role in the formation of MTrPs15,16. Previous animal studies have found that FSN treatment for chronic pain in rats improves the morphological structure and function of mitochondria in TMs to some extent, validating the potential of FSN therapy to promote the recovery of damaged nerves and muscles17.
Sciatica has been classified as neuropathic pain18. The origin of neuropathic pain is thought to lie anywhere between the motor endplate and the outer fibrous layer of the muscle, involving the microvascular system and neurotransmitters at the cellular level. Loss of muscle innervation and apoptosis of innervated nerve cells occurs when nerve damage occurs19, leading to pain-related gait in the affected limb. Additionally, chronic compression or irritation of the nerve can lead to a variety of changes in the way of nerve functions, which can further exacerbate the symptoms of sciatica20. However, the complexity of the nervous system makes it difficult to replicate it in vitro, thus necessitating the use of animal models for such studies. In the investigation of neuropathic pain disorders, model organisms are commonly employed, involving various methods of direct peripheral nerve injury, such as sciatic nerve ligature, transection, or compression21,22. The chronic constriction injury (CCI) model in Sprague-Dawley rats has been used to induce neuropathic pain. This model replicates the pain induced by nerve injury observed in humans through surgical constriction of a peripheral nerve, mimicking the compression or entrapment seen in conditions such as nerve compression syndromes and peripheral neuropathies.
In this study, we evaluated the analgesic effects of FSN therapy and low-frequency electrotherapy (transcutaneous electrical nerve stimulator, TENS) in rats with chronic constriction injury and neuropathic pain. As anesthesia slows or blocks nerve impulses and affects synaptic transmission and neuronal function23, animals cannot be anesthetized under all needling procedures and swaying movements. Therefore, an appropriate needle technique is required to reduce discomfort in rats. The steps for establishing a rat CCI model, the way the rats were treated with FSN combined swaying movement without anesthesia, feasible animal behavioral pattern tests, and electrophysiological investigations are described in detail.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Forceps</td>
			<td>World Precision Instruments</td>
			<td>14098</td>
			<td></td>
		</tr>
		<tr>
			<td>Fu&#8217;s subcutaneous needling</td>
			<td>Nanjing Paifu Medical Science and Technology Co.&#160;</td>
			<td></td>
			<td>FSN needles are designed for single use. The FSN needle is made up of three parts: a solid steel needle core (bottom), a soft casing pipe (middle), and a protecting sheath (top).</td>
		</tr>
		<tr>
			<td>Medelec Synergy electromyography</td>
			<td>Oxford Instrument Medical Ltd.</td>
			<td>034W003&#160;</td>
			<td>Electromyogram (EMG) are used to help in the diagnosis and management of disorders such as neuropathies. Contains a portable two-channel electromyography/nerve conduction velocity system.</td>
		</tr>
		<tr>
			<td>Normal saline (0.9%) 20 mL</td>
			<td>Taiwan Biotech Co.,Ltd.</td>
			<td>4711916010323</td>
			<td>Lot: 1TKB2022</td>
		</tr>
		<tr>
			<td>POLYSORB 4-0 VIOLET 30&#34; CV-25</td>
			<td>UNITED STATES SURGICAL, A DIVISION OF TYCO HEALTHC</td>
			<td>GL-181</td>
			<td></td>
		</tr>
		<tr>
			<td>Retractor</td>
			<td>COOPERSURGICAL, INC.(USA)</td>
			<td>3311-8G</td>
			<td></td>
		</tr>
		<tr>
			<td>Rompun</td>
			<td>Elanco Animal Health Korea Co. Ltd.</td>
			<td>27668</td>
			<td></td>
		</tr>
		<tr>
			<td>SCISSORS CVD 90MM</td>
			<td>BBRUAN</td>
			<td>XG-LBB-BC101R</td>
			<td></td>
		</tr>
		<tr>
			<td>Transcutaneous Electrical Nerve Stimulation</td>
			<td>Well-Life Healthcare Co.</td>
			<td>Model Number 2205A</td>
			<td>Digital unit which offers TENS. Supplied complete with patient leads, self-adhesive electrodes, 3 AAA batteries and instructions in a soft carry bag. Interval ON time 1&#8211;30 s. Interval OFF time 1&#8211;30 s.</td>
		</tr>
		<tr>
			<td>Zoletil&#160;</td>
			<td>VIRRBAC</td>
			<td>8V8HA</td>
			<td></td>
		</tr>
	</tbody>
</table>

efficacy of fu's subcutaneous needling on sciatic nerve pain: behavioral and electrophysiological changes in a chronic constriction injury rat model

Fu&#39;s subcutaneous needling (FSN), an invented acupuncture technique from traditional Chinese medicine, is used worldwide for pain relief. However, the mechanisms of action are still not fully understood. During FSN treatment, the FSN needle is inserted and retained in the subcutaneous tissues for a long duration with a swaying movement. However, challenges arise from maintaining a posture while manipulating FSN in animal models (e.g., rats) for researchers. Uncomfortable treatment can lead to fear and resistance to FSN needles, increasing the risk of injury and may even affect research data. Anesthesia may also affect the study results too. Hence, there is a need for strategies in FSN therapy on animals that minimize injury during the intervention. This study employs a chronic constriction injury model in Sprague-Dawley rats to induce neuropathic pain. This model replicates the pain induced by nerve injury observed in humans through surgical constriction of a peripheral nerve, mimicking the compression or entrapment seen in conditions such as nerve compression syndromes and peripheral neuropathies. We introduce an appropriate manipulation for easily inserting an FSN needle into the subcutaneous layer of the animal&#39;s body, including needle insertion and direction, needle retention, and swaying movement. Minimizing the rat&#39;s discomfort prevents the rat from being tense, which causes the muscle to contract and hinder the entry of the needle and improves the study efficiency.

Author Spotlight: Unveiling the Therapeutic Effects of FSN Treatment &amp;#8211; Bridging Research and Clinical Applications in Neuropathic Pain

Efficacy of Fu's Subcutaneous Needling on Sciatic Nerve Pain: Behavioral and Electrophysiological Changes in a Chronic Constriction Injury Rat Model

Footprints and determination of the SFI 
We examined the development of SFI in the CCI alone, CCI+FSN, and CCI+TENS groups (Figure 7). After 4 sessions of FSN and TENS treatments on day 7 for CCI surgery, the SFI in the CCI+FSN (-15.85 &#177; 3.46) and CCI+TENS (-29.58 &#177; 9.19) groups improved significantly compared to the CCI alone group (-87.40 &#177; 14.22). The improvement was significant in the CCI+FSN group compared to the CCI+TENS group&#160;(<strong class="x...

Watch this Scientific Journal Video about Efficacy of Fu's Subcutaneous Needling on Sciatic Nerve Pain: Behavioral and Electrophysiological Changes in a Chronic Constriction Injury Rat Model at JoVE.c

We present a protocol for using Fu's subcutaneous needling in a chronic constriction injury model to induce sciatic nerve pain in rats.

Fu&#39;s subcutaneous needling (FSN), an invented acupuncture technique from traditional Chinese medicine, is used worldwide for pain relief. However, the ...

efficacy-fu-s-subcutaneous-needling-on-sciatic-nerve-pain-behavioral