Electroacupuncture for chronic stroke has been used in stroke rehabilitation in China from ancient times. Results from recent clinical studies, however, have been conflicting. Some past studies have demonstrated the effectiveness of acupuncture treatment in stroke rehabilitation [1-7]. Other studies reported different findings [8-11]. For instance, a recent meta-analysis of past clinical trials in the literature concluded that acupuncture had no additional effect on motor recovery but did have a positive effect on disability . The discrepancy in the literature on the effects of acupuncture treatment in stroke rehabilitation may be partially due to the broadly defined objectives used in past studies. For instance, motor functional recovery after stroke is a motor relearning process. The improvement in motor learning is dependent on the amount of practice . The cortical plasticity that accompanies motor recovery after a brain lesion has been shown to depend strongly on training and repetitive practice [14-17]. Acupuncture treatment alone, usually applied while resting, may not bring direct benefits to motor functional recovery.
The effect of acupuncture in stroke rehabilitation may be better demonstrated when a subgroup of people with a specific type of stroke impairment is the target . Existing clinical data, empirical studies, and anecdotal evidence have suggested that acupuncture may release spasticity in individuals after stroke [19-24]. Recent studies indicated that muscle spasticity occurs in only a portion of stroke survivors [25-27]. Acupuncture treatment may be used in this subgroup of stroke survivors to reduce muscle spasticity and probably further improve motor function if used in combination with a motor training program. Muscle weakness is common and has been shown to be a more disabling factor in stroke survivors than spasticity [28-30]. Some past studies have reported a positive effect of strengthening exercises in stroke rehabilitation [31-33]. A combination of acupuncture treatment and strength training may be a better treatment option for stroke survivors with both muscle weakness and spasticity. The question is whether or not acupuncture treatment can result in additional benefit to individuals’ motor function when combined with a strength training program.
The purpose of this study was to assess the effect of combined acupuncture and strength training treatment (AS) in a group of chronic stroke survivors based on clinical and quantitative measurements of motor function.
All subjects participated in a crossover design of two types of treatment: AS and strength training treatment (S) alone. Each treatment lasted for a total of 6 weeks, with two treatment sessions a week on two different days. The order of the two treatments was randomly assigned. The AS phase consisted of 40 minutes of electroacupuncture treatment and 30 minutes of strengthening exercises. The S phase included only the strengthening exercises.
The electroacupuncture protocol was similar to a previous study  with some modification, including two more acupressure points and a different stimulation frequency; these modifications were based primarily on the personal experience of a member of the research team who is also a licensed acupuncturist. The areas of skin selected for needling were cleaned with 75 percent alcohol. The needles were single-use, disposable steel acupuncture needles (Seirin, OMS Medical Supplies Inc; Braintree, Massachusetts), with a diameter of 0.2 mm and a length of 60 mm. The needles were inserted into the following acupressure points on the subject’s hemiparetic arm: (1) Hegu (large intestine [LI] 4), (2) Houxi (small intestine [SI] 3), (3) Waiguan (triple warmer [TW] 5), (4) Quchi (LI 11), (5) Shousanli (LI 10), and (6) Jianyu (LI 15) (Figure 1). During insertion, the needles were inserted perpendicularly into all six acupuncture points, forming a 90× angle with the skin surface. The depth of needle insertion was approximately 10 mm for LI 11 and TW 5 and 15 mm for all other acupuncture points. After insertion of needles into the tissue, alternating current was passed between the two nearest needles (LI 4 with SI 3, TW 5 with LI 11, and LI 10 with LI 15) with a commercial electroacupuncture device (model ITO-4107, OMS Medical Supplies Inc; Braintree, Massachusetts). Current pulses were set at 2 Hz. The intensity of the current was increased to the point where the patient reported the needling reaction and then it was reduced slightly to an unpleasant but tolerable intensity. The “needling reaction” is the characteristic response of a subject to acupuncture needle insertion and manipulation. The subject reports an acute, strongly aversive sensation that is restricted to the site of needle insertion. After a period of 5 to 10 minutes, when the subject had become sensitized to the stimulus, we increased it slightly and then maintained the current at that level for 30 minutes. We used electroacupuncture rather than manual acupuncture in this study to ensure that all the needle stimuli were handled in the same manner.
Spasticity measurement data from two of our subjects were excluded from data analysis because of technical problems encountered during data acquisition. The data analysis of spasticity reported here came from the remaining eight subjects. The VASRT values showed a significant (p < 0.05) change from 0.0092 ± 0.0068 to 0.0068 ± 0.0057 after the AS phase (all data presented as mean ± standard deviation unless otherwise noted). The changes in VASRT values before and after the S phase were not significant (p = 0.24), with a small decrease in mean values from 0.0067 ± 0.0057 to 0.0058 ± 0.0033. A previous report included more details on the changes in spasticity . The mean wrist extension ROM values are presented in Figure 2. The baseline value was the mean of the first measurements of all subjects. The pre-AS and post-AS were the means of measurements of all subjects before and after the combined treatment. The pre-S and post-S were the means of measurements of all subjects before and after the strengthening treatment alone. No significant difference was noted between baseline (17.0× ± 19.2×) and pre-AS (20.2× ± 19.8×), but post-AS (36.5× ± 30.6×) was significantly different from baseline and pre-AS (p < 0.05). No significant difference was noted between pre-S (27.0× ± 29.1×) and post-S (28.7× ± 27.1×) but both were significantly different from baseline (p < 0.05). Only two subjects had observable active extensional motion in the index finger of the affected upper limb. The mean change in the extension ROM for these two subjects was 30× after the combined treatment and 0× after the strength training alone.
In conclusion, Electroacupuncture for chronic stroke in this current study showed a significant decrease in muscle spasticity and increases in active ROM of the wrist joint and FM upper-limb motor scores after a combined acupuncture treatment and strengthening exercise intervention. The strengthening alone did not show any beneficial effect on the same subjects. It is premature to draw any firm conclusion given the limitations of this pilot study. It is, however, reasonable to state that the results of the current study indicate a hope that acupuncture treatment may improve motor function if combined with a motor training program in chronic stroke survivors with moderate or severe muscle spasticity.