Therapeutic Efficacy Analysis of Balancing Yin-yang Manipulation for Post-stroke Upper Limb Spasticity

Cui Hua-feng,3,4, Gao Guo-qiang2, Wang Yan-li, Yu Xiao-hua3,4, Guo Li, Ren Shuo

1 Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Shandong 250014, China

2 Tengzhou Central People's Hospital, Shandong 277500, China

3 Shandong University of Traditional Chinese Medicine, Shandong 250355, China

4 Shan Qiu-hua's National Famous Traditional Chinese Medicine Doctors Inheritance Studio, Shandong 250014, China

CLINICAL STUDY

Therapeutic Efficacy Analysis of Balancing Yin-yang Manipulation for Post-stroke Upper Limb Spasticity

Cui Hua-feng1,3,4, Gao Guo-qiang2, Wang Yan-li1, Yu Xiao-hua3,4, Guo Li1, Ren Shuo1

1 Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Shandong 250014, China

2 Tengzhou Central People's Hospital, Shandong 277500, China

3 Shandong University of Traditional Chinese Medicine, Shandong 250355, China

4 Shan Qiu-hua's National Famous Traditional Chinese Medicine Doctors Inheritance Studio, Shandong 250014, China

Author:Cui Hua-feng, doctorate student, attending physician.

E-mail: cuihuafeng@139.com

Objective: To observe the effect of balancing yin-yang needling manipulation on post-stroke upper limb spasticity and changes of electromyography (EMG) after treatment.

Methods: A total of 60 eligible cases were randomly allocated into an observation group and a control group, 30 in each group. Based on routine medication, cases in the control group were treated with conventional needling manipulation, whereas cases in the observation group were treated with balancing yin-yang manipulation. After the courses of treatment were completed, the therapeutic efficacies were evaluated using modified Ashworth scale and clinical spasticity index (CSI), coupled with the integrated electromyography (IEMG) and root mean square (RMS) value of biceps in passive flexion of the elbow joint during isokinetic testing recorded with the surface EMG.

Results: The total effective rate in the observation group was 86.7%, versus 53.3% in the control group, showing a statistical significance (P＜0.05). After treatment, there was between-group statistical significance in severity of elbow spasticity (P＜0.05); there were intragroup (P＜0.01,P＜0.05) and inter-group (P＜0.05) statistical significances in CSI index; and there were intra-group (P＜0.01,P＜0.05) and inter-group (P＜0.01,P＜0.05) statistical significances in IEMG and RMS values.

Conclusion: Balancing yin-yang and conventional needling manipulations can both improve upper limb spasm and reduce CSI as well as IEMG and RMS values in stroke patients; however, balancing yin-yang manipulation is better than conventional manipulation in clinical effect.

Stroke; Cerebral Hemorrhage; Brain Infarction; Complications; Muscle Spasticity; Acupuncture Therapy

Increased muscle tone or spasticity of the affected limb is commonly seen in stroke patients, often manifesting as spasticity of the flexor muscles in the upper limb and extensor muscles in the lower limb. Spasticity affects patient’s daily living such as personal hygiene and clothes washing. Early-stage spasticity often results in abnormal motor pattern and delay recovery of the motor function. Late-stage spasticity often results in contracture and malformation of joints or even lifelong disability. As a result, it’s crucial to interrupt the hemiplegic spasticity for stroke recovery. In Chinese medicine, spasticity is explained as ‘disorders of Yang Heel Vessel manifesting as flaccidity of the yang side and spasm of the yin side; whereas disorders of the Yin Heel Vessel manifesting as flaccidity of the yin side and spasm of the yang side’. The treatment principle is therefore to harmonize and balance yin and yang. Based on this theory, balancing yin-yang manipulation works on points on the affected side to reduce muscle tone,improve the limb function and motor ability and thus form a normal motor pattern. We’ve treated post-stroke spasticity with balancing yin-yang needling manipulation over the past years. The results are now summarized as follows.

1 Clinical Materials

1.1 Diagnostic criteria

1.1.1 Diagnosis in Western medicine

This is based on the diagnostic criteria for cerebral infarction and hemorrhage in theKey Diagnostic Points for Cerebrovascular Diseasesthat revised at the 4th National Conference of Chinese Medical Association in 1995[1], coupled with CT scan or MRI examination.

Key diagnostic points for cerebral hemorrhage: sudden onset during physical exertion or emotional fluctuation, recurrent vomiting, headache and elevated blood pressure, rapid progression with complications of disturbance of consciousness, hemiplegia and other local focus symptom of nervous system; a history of hypertension; CT scan as the first recommended; lumbar puncture of cerebrospinal fluid often contains blood and increased pressure (no blood in approximately 20% patients).

Key diagnostic points for cerebral infarction: onset during a resting state; no notable headache or vomiting; a slow onset with gradual progression, often related to cerebral atherosclerosis, arteritis and blood diseases; clear consciousness or mild disturbance within 1-2 d of onset; signs and symptoms of internal carotid artery and/or vertebrobasilar artery system; CT scan or MRI examination as first recommended; lumbar puncture of cerebrospinal fluid does not contain blood.

1.1.2 Diagnostic criteria in Chinese medicine

This is based on theCriteria of Diagnosis and Therapeutic Effects of Diseases and Syndromes in Traditional Chinese Medicineissued by the State Administration of Traditional Chinese Medicine in 2012[2]. Major symptoms include hemiplegia, deviation of the mouth and tongue, tongue stiffness, numbness on one side of the body, mental confusion, loss of consciousness and drowsiness; a sudden onset with gradual progression; warning signs include dizziness, headache and limb numbness. Contributing factors include aging, debility, overexertion, smoking or drinking alcohol and intake of sweet fatty food. Inducing factors include anger, fatigue, excessive drinking and contraction of cold; required examinations include blood pressure, nervous system, cerebrospinal fluid, blood routine and eye ground. CT scan or MRI examination was recommended.

1.2 Inclusion criteria

Those who met the criteria of intracranial artery system cerebral infraction or hemorrhage and have duration of less than 8 weeks; II, III and V stage by Brunnstrom approach; muscle tone≥1 but ≤3 according to modified Ashworth scale; spasticity of flexor muscles in the upper limb; men or women aged between 30 and 65 years; having stable vital signs and good cognitive function; willing to participate in this trial and signed the informed consent.

1.3 Exclusion criteria

Those with deteriorated condition, new brain infarction or hemorrhage; recent epilepsy seizures that are poorly controlled; having complications of Parkinson’s disease or syndrome; having severe cardio-cerebrovascular diseases and life-threatening conditions involving the liver, kidney and blood systems; having mental disorders; and pregnant or breast-feeding women.

1.4 Statistical method

Analysis was performed with SPSS 17.0 version software. Measurement data that accord with positive distribution were expressed withDifferences between groups were tested with One-way analysis of variance. Intra-group differences were tested with Two-way analysis of variance. Ranked data were compared withRiditanalysis. Enumeration data were compared with the Chi-square test.

1.5 General data

The 60 eligible patients (some were outpatients, some were inpatients) in this study all presented with post-stroke spasticity. They were randomly allocated into an observation group and a control group, 30 in each group. There were no between-group statistical significances in gender, age, duration and spasticity severity (P＞0.05), indicating that the two groups were comparable (Table 1).

Table 1. Between-group comparison of general data

2 Treatment Methods

The patients were randomly allocated into two groups by the random number table. Speciallyassigned personnel kept the random allocation cards and distributed to eligible subjects. The subjects then received the treatment protocol on the card.

2.1 Observation group

Cases in the observation group were treated with balancing yin-yang manipulation.

Points of yin meridians: Jiquan (HT 1), Chize (LU 5) and Neiguan (PC 6).

Points of yang meridians: Jianyu (LI 15), Quchi (LI 11) and Hegu (LI 4).

Method: Jiquan (HT 1), Chize (LU 5) and Neiguan (PC 6) were punctured perpendicularly in sequence using filiform needles of 0.38 mm in diameter and 50 mm in length, followed by reducing manipulation by twirling (100 times/min) to enable the electric shock or soreness/distension sensation to radiate along the arm (do not cause a large-amplitude twitching of the arm) and remove the needles afterwards. Then points on yang meridians were punctured in the same way, followed by reinforcing manipulation by lifting, thrusting and twirling. The lifting-thrusting amplitude was 1-3 cm according to the muscle thickness and the frequency of twirling was 100 times/min. Jianyu (LI 15) and Quchi (LI 11) on the affected side were connected to HANS-100A pain management device, using a sparse-dense wave of 2 Hz/100 Hz and current intensity of 6 mA. The treatment was done once a day, and 6 times made up a course of treatment. There was a 1-day interval between two courses. The therapeutic efficacies were observed after two courses of treatment.

2.2 Control group

Cases in the control group were treated with conventional needling manipulation.

Points: Jianyu (LI 15), Quchi (LI 11), Waiguan (TE 5) and Hegu (LI 4).

Method: The patient was asked to take a supine position, extend the affected arm and turn the palm to the torso. The same filiform needles as used in the observation group were used to puncture the above points, followed by even reinforcing-reducing lifting, thrusting and twirling manipulation. The lifting and thrusting amplitude ranged 1 to 3 cm according the muscle thickness. The twirling frequency was 100 times/min. Jianyu (LI 15) and Quchi (LI 11) on the affected side were connected to the pain management device, using the same frequency, current intensity, stimulation duration and course of treatment as in the observation group.

3 Therapeutic Efficacy Observation

3.1 Observation indices

3.1.1 Modified Ashworth scale (MAS)[4]

The elbow joint spasticity was assessed before and after treatment using MAS. The spasticity was graded from 0 to 4 (plus a 1+) as follows.

Grade 0: No increase in muscle tone.

Grade 1: Slight increase in muscle tone, manifested by a catch and release or by minimal resistance at the end of the range of motion (ROM) when the affected part(s) is moved in flexion or in extension.

Grade 1+: Slight increase in muscle tone, manifested by a catch, followed by minimal resistance throughout the reminder (less than half) of the ROM.

Grade 2: More marked increase in muscle tone throughout most of the ROM, but affected part(s) easily moved.

Grade 3: Considerable increase in muscle tone, passive movement was difficult.

Grade 4: Affected part(s) rigid in flexion or extension.

3.1.2 Clinical spasticity index (CSI)[5]

The upper limb spasticity was assessed before and after treatment using CSI, including 3 items, namely, tendon jerk, muscle tone and clonus.

Tendon jerk (biceps): No response scores 0; weak response scores 1; normal response scores 2; hyperactive response scores 3; maximally hyperactive response scores 4.

Muscle tone (resistance to full range passive joint displacement): No resistance scores 0; reduced resistance scores 2; normal resistance scores 4; mildly increased resistance scores 6; maximally increased resistance scores 8.

Clonus (wrist or ankle): Clonus not elicited scores 1; 1-2 beats of clonus elicited scores 2; ＞2 beats of clonus elicited scores 3; ＞30 beats of clonus elicited scores 4.

The spasticity was evaluated according to global scores of the above three items: no spasticity scores 0-6; mild spasticity scores 7-9; moderate spasticity scores 10-12; and severe spasticity scores 13-16.

3.1.3 Integrated electromyography (IEMG) and root mean square (RMS) average value

The surface EMG was used for isokinetic testing and recording of IEMG and RMS average value ofbiceps during passive flexion of the elbow joint.

Examination: The patient was asked to sit on a chair, relax (relax with no subjective physical exertion) and conduct a 60°/s (angular velocity) passive movement of the elbow joint in an isokinetic testing system. The surface myoelectric activities of the biceps (during passive flexion) for the initial 6 times were measured for IEMG statistical analysis using the Infinite 3000 version software to obtain RMS average value. The range of elbow joint motion was 0-120°.

Since IEMG refers to the integral electric discharge of involved muscle activity in a given time, it’s, to some degree, positively correlated to muscle tone. As RMS refers to the root mean value of the surface electromyography amplitude, a bigger value indicates a bigger muscle tone.

3.2 Clinical efficacy evaluation

This is conducted on CSI according to theIntroduction to Four-level Weighted Scoring for Clinical Diagnosis and Efficacy Evaluation[6].

Reduction rate of integral difference (RRID)＝(Pretreatment score－Post-treatment score)÷Pretreatment score×100%.

Recovery: The RRID reached 100%.

Marked effect: The RRID ≥67%, but ＜100%.

Improvement: The RRID ≥33%, but ＜67%.

Failure: The RRID ＜33%.

3.3 Treatment results

3.3.1 Between-group comparison in clinical efficacy

The total effective rate in the observation group was 86.7%, versus 53.3% in the control group, showing a statistical significance (P＜0.05) and indicating a better effect in the observation group than that in the control group (Table 2).

Table 2. Between-group comparison in clinical efficacy (case)

3.3.2 Between-group comparison in elbow spasm

TheRiditanalysis showed intra-group statistical significances in elbow spasticity in both groups after treatment (P＜0.05), indicating that both methods can alleviate upper limb spasticity. The betweengroup statistical significance in elbow spasm (P＜0.05) indicates a better effect in the observation group in improving elbow spasticity (Table 3).

Table 3. Between-group comparison of elbow joint spasticity before and after treatment (case)

3.3.3 Between-group comparison in CSI score

After treatment, there were intra-group statistical significances in CSI scores (P＜0.01,P＜0.05), indicating that both methods can significantly reduce CSI score. The between-group statistical significance in CSI score (P＜0.05) indicates a better effect in the observation group than that in the control group (Table 4).

3.3.4 Between-group comparison in IEMG and RMS value of the affected biceps

After treatment, there were intra-group (P＜0.01,P＜0.05) and inter-group (P＜0.01) statistical significances in IEMG and RMS values of biceps in flexion of the affected elbow joint, indicating a more significant reduction of IEMG and RMS in the observation group than that in the control group (Table 5).

Table 4. Between-group comparison of CSI score (point)

Table 4. Between-group comparison of CSI score (point)

Note: Intra-group comparison before and after treatment, 1) P＜0.01, 2) P＜0.05; compared with the control group after treatment, 3) P＜0.05

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Table 5. Between-group comparison in EMG

Table 5. Between-group comparison in EMG

Note: Intra-group comparison before and after treatment, 1) P＜0.01, 2) P＜0.05; compared with the control group after treatment, 3) P＜0.05

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4 Discussion

Muscle spasm is one of the common sequelae of stroke. In Chinese medicine, it falls under the category of ‘pian ku(partial paralysis)’, ‘wind stroke’, and ‘tendon Bi-Impediment’. As for etiology and pathogenesis of muscle spasm, the 29th difficult issue in theNan Jing(Classic of Difficult Issues) states,‘Disorders of Yang Heel Vessel manifest as flaccidity of the yang side and spasm of the yin side; whereas disorders of Yin Heel Vessel manifest as flaccidity of the yin side and spasm of the yang side’. This indicates that post-stroke limb spasm results from yin-yang disorder. Contributing factors include obstruction of brain collaterals, disordered qi, blood, yin and yang and subsequent malnourishment of muscles and tendons. Consequently, the treatment principle of spasm is to harmonize yin and yang. Stroke patients often present spasm of flexor muscles in the upper limb (yang flaccid and yin spasm) and hyperextension of extensor muscles in the lower limb (yin flaccid and yang spasm). As a result, acupuncture treatment aims to supplement qi and blood, regulate meridians and balance yin and yang.

The concept of ‘spasticity’ was first proposed by a British scholar in 1980 on the basis of neurophysiology theory, who believes that spasticity is one component of the upper motor neuron (UMN) syndrome[7]in the form of a lesion, a velocitydependent increase in tonic stretch reflexes with exaggerated tendon jerks, resulting from hyperexcitability of the stretch reflex. In 1994, according to the nervous system control theory, some scholars broadened the definition of ‘spasticity’ as ‘a motor disorder characterized by a velocity dependent increase in tonic stretch reflexes that results from abnormal intra-spinal processing of primary afferent input’[8]. In 2005, according to biomechanics and motor control theory, some scholars proposed the new ‘biomechanical factor’, i.e., myogenic factor and held that spasticity is impaired sensory-motor control derived from upper motor neuron damage, manifested as intermittent or remaining nonvoluntary muscle activation[9]. At present, the 1980 definition was well accepted by scholars and neurophysiology textbooks in China. In addition, some scholars maintained that early-phase spasticity is mainly associated with reflex mediation and later-phase spasticity is more associated with myogenic factors (secondary changes of muscle fibers and partial repair nerve fibers)[10-11]. As a result, contracture and malformation of limbs often occur in later stage of stroke.

MAS is now commonly used for post-stroke spasticity evaluation. The spasticity was graded from 0 to 4, plus a 1+. However, the credibility of MAS is now challenged by more objective muscle tension meters. By an experiment on evaluating passive range of movement with biomechanical device and MAS, Kumar RT, et al concluded that biomechanical method is better than MAS in reliability and validity in differentiating spasticity severity[12]. Some scholars from abroad proposed that spasticity should be evaluated by EMG combined with biomechanical device: the EMG for spasticity due to nerve reflex and biomechanical device for myogenic spasticity (secondary changes of muscle fibers and collagen tissues). This can help us with a better understanding of spasticity mechanism, since spasticity varies in causative factors. They believe that MAS fails to differentiate myogenic spasticity from nerve reflex spasticity[13-15]. However, MAS is still the most common method for clinical spasticity measurement because it is safe, convenient, low-cost, and has acceptable reliability and validity. Through clinical studies and researches, some scholars found post-stroke spasticity may be beneficial. For patients with complete paralysis, mild spasm can prevent osteoporosis, muscular atrophy and help them to stand. However, severe spasticity can affect the patient's standing posture, motor morphology and gait[13-14]. Severe spasticity deserves more attention. To some scholars, higher degrees of spasticity (MAS≥3) are considered severe spasticity or disability spasticity byInternational Classification of Functioning, Disability & Health[15-16]. Post-stroke spasticity can be alleviated by numerous therapies such as surgery, injection, physical therapy and medication. The CSI[17-18]proposed by a Canadian scholar Levin MF, et al in 1990s containing tendon jerk, muscle tone and clonus can evaluate more items than MAS. However, just like MAS, CSI is also subjective and conducted by rehabilitation physicians or therapists, and thus susceptible to errors. At present, objective evaluation methods for post-stroke spasticity include neurophysiological and biomechanical methods. Following UMN damage, one can observe electro-physiological changes resulting from failure of the spinal cord to control the brain stem and brain and subsequent displacement of the intra-segmental motion and intermediate neuron[19]. EMG can objective assess spasticity, using IEMG and RMS for analysis of time domain. IEMG and RMS are, to some extent, positively correlated to muscle tone: a bigger value indicates a bigger muscle tone. In 1980s, scholars from abroad started to use biomechanical measurement (isokinetic device)[20]for quantitative evaluation on post-stroke spasticity. Since it is more objective, this method has been increasingly used in the past 20 years for quantitative evaluation and reference for other assessment methods[20]. This study used surface EMG to measureIEMG and RMS (isokinetic test): reduced IEMG and RMS indicate an alleviation of spasticity. This can compensate for MAS and CSI and is of great significance.

Chinese medicine holds that post-stroke spasticity is mainly caused by disorders of yin or yang meridians and subsequent imbalance of yin and yang sides (flaccid in one side and spasm in the other side). Consequently, points in yin and yang meridians were selected to harmonize and balance yin and yang. Since stroke is associated with all twelve regular meridians, points of these meridians were selected, coupled with needing points in yin and yang meridians to harmonize yin and yang[21-22]. In terms of anatomy in modern medicine, stroke manifests as hyperexcitability of extensor muscles in the lower limb and flexor muscles in the upper limb as well as inhibition of flexor muscles in the lower limb and extensor muscles in the upper limb, the treatment should therefore be aimed at inhibiting spastic muscles but activating weak muscles. In other words, the muscle tone balance can be restored by applying either reinforcing or reducing manipulation to points in yin or yang meridians[23].

Conflict of Interest

There was no potential conflict of interest.

Acknowledgments

This work was supported by Shandong Provincial Science & Technology Development Project for Traditional Chinese Medicine (No. 2013ZDZK-011); Leading Discipline Project of Acupuncture, Shandong University of Traditional Chinese Medicine Funded by the State Administration of Traditional Chinese Medicine.

Statement of Informed Consent

All of the patients signed the informed consent.

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Translator: Han Chou-ping

Received Date: August 10, 2014

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in both groups

conventional basic treatment such as medications for hypertension and coronary artery diseases; however, they were not allowed to take medications that may affect motor function and/or reduce muscle tone. Locations of points in both groups were based on theMeridians and Points[3].