Ta Shen Kuan

Dry needling to a key Myofascial trigger point may reduce the irritability of satellite MTrPs

Hsieh Y-L, Kao M-J, Kuan T-S, Chen S-M, Chen J-T, Hong C-Z: Dry needling to a key myofascial trigger point may reduce the irritability of satellite myofascial trigger points. Am J Phys Med Rehabil 2007;86:397–403. Objective:To investigate the changes in pressure pain threshold of the secondary (satellite) myofascial trigger points (MTrPs) after dry needling of a primary (key) active MTrP. Design:Single blinded within-subject design, with the same subjects serving as their own controls (randomized). Fourteen patients with bilateral shoulder pain and active MTrPs in bilateral infraspinatus muscles were involved. An MTrP in the infraspinatus muscle on a randomly selected side was dry needled, and the MTrP on the contralateral side was not (control). Shoulder pain intensity, range of motion (ROM) of shoulder internal rotation, and pressure pain threshold of the MTrPs in the infraspinatus, anterior deltoid, and extensor carpi radialis longus muscles were measured in both sides before and immediately after dry needling. Results:Both active and passive ROM of shoulder internal rotation, and the pressure pain threshold of MTrPs on the treated side, were significantly increased (P < 0.01), and the pain intensity of the treated shoulder was significantly reduced (P < 0.001) after dry needling. However, there were no significant changes in all parameters in the control (untreated) side. Percent changes in the data after needling were also analyzed. For every parameter, the percent change was significantly higher in the treated side than in the control side. Conclusions:This study provides evidence that dry needle–evoked inactivation of a primary (key) MTrP inhibits the activity in satellite MTrPs situated in its zone of pain referral. This supports the concept that activity in a primary MTrP leads to the development of activity in satellite MTrPs and the suggested spinal cord mechanism responsible for this phenomenon.

Hemiplegic gait of stroke patients: The effect of using a cane

OBJECTIVE To assess the effects of cane use on the hemiplegic gait of stroke patients, focusing on the temporal, spatial, and kinematic variables. DESIGN Case-control study comparing the effect of walking with and without a cane using a six-camera computerized motion analysis system. SETTING Stroke clinic of a tertiary care hospital. PARTICIPANTS Fifteen ambulatory stroke patients were analyzed, including 10 men and 5 women (mean age, 56.9 years; mean time since stroke, 9.8 weeks). Nine age-matched healthy elderly subjects were recruited as a control group. RESULTS Stroke patients walking with a cane showed significantly increased stride period, stride length, and affected side step length, as well as decreased cadence and step width (p < .05) in comparison with those who walked without a cane. There were no significant differences in the gait phases and the five gait events of hemiplegic gait walking with or without a cane. Cane use thus may have more effect on spatial variables than on temporal variables. The affected-side kinematics of hemiplegic gait with a cane showed increased pelvic obliquity, hip abduction, and ankle eversion during terminal stance phase; increased hip extension, knee extension, and ankle plantar-flexion during preswing phase; and increased hip adduction, knee flexion, and ankle dorsiflexion during swing phase as compared with hemiplegic gait without a cane. A cane thus improved the hemiplegic gait by assisting the affected limb to smoothly shift the center of body mass toward the sound limb and to enhance push off during preswing phase. It also improved circumduction gait during swing phase. CONCLUSION Stroke patients walking with a cane demonstrated more normal spatial variables and joint motion than did those without a cane.

The immediate effectiveness of electrical nerve stimulation and electrical muscle stimulation on myofascial trigger points

This study is designed to investigate the immediate effectiveness of electrotherapy on myofascial trigger points of upper trapezius muscle. Sixty patients (25 males and 35 females) who had myofascial trigger points in one side of the upper trapezius muscles were studied. The involved upper trapezius muscles were treated with three different methods according to a random assignment: group A muscles (n = 18) were given placebo treatment (control group); group B muscles (n = 20) were treated with electrical nerve stimulation (ENS) therapy; and group C muscles (n = 22) were given electrical muscle stimulation (EMS) therapy. The effectiveness of treatment was assessed by conducting three measurements on each muscle before and immediately after treatment: subjective pain intensity [(PI) with a visual analog scale], pressure pain threshold [(PT) with algometry], and range of motion [(ROM) with a goniometer] of upper trapezius muscle (lateral bending of cervical spine to the opposite side). When the effectiveness of treatment was compared with that of the placebo group (group A), there was significant improvement in PI and PT in group B (P < 0.01) but not in group C (P > 0.05). The improvement of ROM was significantly more in group C (P < 0.01) as compared with that in group A or group B. When each group was divided into two additional subgroups based on the initial PI, it was found that ENS could reduce PI and increase PT significantly (P < 0.05), but did not significantly (P > 0.05) improve ROM, as compared with the placebo group for both subgroups. EMS could significantly (P < 0.05) improve ROM, but not PT, better than the placebo groups, for either subgroup. It could reduce PI significantly more (P < 0.05) than placebo controls only for the subgroup with mild to moderate pain, but not with severe pain. For pain relief, ENS was significantly better (P < 0.05) than EMS; but for the improvement of ROM, EMS was significantly better (P < 0.05) than ENS. It is concluded that ENS is more effective for immediate relief of myofascial trigger point pain than EMS, and EMS has a better effect on immediate release of muscle tightness than ENS.

Correlating factors and clinical significance of flexible flatfoot in preschool children

To elucidate the correlating factors and clinical significance of flexible flatfoot (FF) in preschool children of Taiwan, a cross-sectional study was conducted in a research laboratory equipped with a gait analysis facility. Altogether, 377 preschool children (201 boys, 176 girls), ranging in age from 2 to 6 years, were enrolled in this investigation. The results show that age, height, weight, foot progression angle, occurrence of physical knock-knee, and joint laxity score correlate with FF. Children with FF, compared with children without, performed physical tasks poorly and walked slowly, as determined by gait parameters. The FF should not simply be regarded as a problem of static alignment of the ankle and foot complex, but may be the consequence of a dynamic functional change of the lower extremity. Better understanding of the correlating factors and the clinical relevance of FF may prove helpful in deciding on the most appropriate treatment for a particular patient.

Inhibitory effect of dry needling on the spontaneous electrical activity recorded from myofascial trigger spots of rabbit skeletal muscle.

Chen JT, Chung KC, Hou CR, Kuan CR, Chen SM, Hong CZ: Inhibitory effect of dry needling on the spontaneous electrical activity recorded from myofascial trigger spots of rabbit skeletal muscle. Am J Phys Med Rehabil 2000;80:729–735. Objective: Dry needling of myofascial trigger points can relieve myofascial pain if local twitch responses are elicited during needling. Spontaneous electrical activity (SEA) recorded from an active locus in a myofascial trigger point region has been used to assess the myofascial trigger point sensitivity. This study was to investigate the effect of dry needling on SEA. Design: Nine adult New Zealand rabbits were studied. Dry needling with rapid insertion into multiple sites within the myofascial trigger spot region was performed to the biceps femoris muscle to elicit sufficient local twitch responses. Very slow needle insertion with minimal local twitch response elicitation was conducted to the other biceps femoris muscle for the control study. SEA was recorded from 15 different active loci of the myofascial trigger spot before and immediately after treatment for both sides. The raw data of 1-sec SEA were rectified and integrated to calculate the average integrated value of SEA. Results: Seven of nine rabbits demonstrated significantly lower normalized average integrated value of SEA in the treatment side compared with the control side (P < 0.05). The results of two-way analysis of variance show that the mean of the normalized average integrated value of SEA in the treatment group (0.565 ± 0.113) is significantly (P < 0.05) lower than that of the control (0.983 ± 0.121). Conclusions: Dry needling of the myofascial trigger spot is effective in diminishing SEA if local twitch responses are elicited. The local twitch response elicitation, other than trauma effects of needling, seems to be the primary inhibitory factor on SEA during dry needling.

Remote effects of dry needling on the irritability of the myofascial trigger point in the upper trapezius muscle.

Tsai C-T, Hsieh L-F, Kuan T-S, Kao MJ, Chou L-W, Hong C-Z: Remote effects of dry needling on the irritability of the myofascial trigger point in the upper trapezius muscle. Objective:To investigate the remote effect of dry needling on the irritability of a myofascial trigger point in the upper trapezius muscle. Design:Thirty-five patients with active myofascial trigger points in upper trapezius muscles were randomly divided into two groups: 18 patients in the control group received sham needling, and 17 patients in the dry-needling group received dry needling into the myofascial trigger point in the extensor carpi radialis longus muscle. The subjective pain intensity, pressure pain threshold, and range of motion of the neck were assessed before and immediately after the treatment. Results:Immediately after dry needling in the experimental group, the mean pain intensity was significantly reduced, but the mean pressure threshold and the mean range of motion of cervical spine were significantly increased. There were significantly larger changes in all three parameters of measurement in the dry-needling group than that in the control group. Conclusions:This study demonstrated the remote effectiveness of dry needling. Dry needling of a distal myofascial trigger point can provide a remote effect to reduce the irritability of a proximal myofascial trigger point.

Phentolamine effect on the spontaneous electrical activity of active loci in a myofascial trigger spot of rabbit skeletal muscle

OBJECTIVE To investigate the effect of phentolamine, a sympathetic blocking agent, on the spontaneous electrical activity (SEA) recorded from a locus of a myofascial trigger spot (MTrS), equivalent to a human trigger point, in rabbit skeletal muscle. DESIGN Randomized control trial. SETTING A university medical laboratory. PATIENTS OR OTHER PARTICIPANTS Nine adult New Zealand rabbits. INTERVENTION In the experimental group phentolamine mesylate (1mg/kg) was injected into the external iliac artery, followed by flushing with normal saline. The control group was treated with normal saline instead of phentolamine using the same procedure. MAIN OUTCOME MEASURES SEA was recorded from multiple active loci of MTrSs in the biceps femoris muscle: initially SEA in the same locus was recorded before and immediately after phentolamine (or normal saline) injection; then SEA was recorded from 25 different active loci. The mean of the average integrated signal (AIS) of SEA was analyzed, comparing the effects of phentolamine and normal saline on SEA. RESULTS In the same active locus, the AIS of SEA showed statistically a linear decay with time after phentolamine injection, with a correlation coefficient of .56 at p < .05. However, no statistical relationship could be derived for the control group data with time by using regression analysis, probably because of large variations among the rabbits and movement artifacts during the experiment. In 25 different loci in the phentolamine group, the mean of the AIS of SEA (7.92 microV) was significantly lower than that of the control group (9.89 microV) at p < .05. CONCLUSIONS The results support the hypothesis that the autonomic nervous system is involved in the pathogenesis of myofascial trigger points. The application of the AIS as an evaluation index seems to be feasible in the quantitative measurement of SEA.

Performance of static standing balance in children with spastic diplegic cerebral palsy under altered sensory environments

Seven children with spastic diplegic cerebral palsy and 14 age- and gender-matched nondisabled children participated in the present study for an investigation and comparison of their static standing balance under altered sensory environments. The type of visual input (full, occluded, or sway referenced vision) and the type of somatosensory input (fixed or compliant foot support) were varied factorially to give six sensory environments. Each participant was tested barefooted for 30 s under all six conditions. A force platform collected the ground reaction force, from which standing balance was calculated as the sway area of the center of pressure. The results showed that when somatosensory information was reliable (fixed foot support), there was no significant difference in stance stability between the children with spastic diplegic cerebral palsy and their matched controls, and both types of children were equally affected by the type of visual input. However, when somatosensory information was unreliable (compliant foot support), the difference in stance stability between the children with spastic diplegic cerebral palsy and their matched controls was significantly greater when the visual input was deprived (occluded) or unreliable (sway referenced) than when it was reliable. These results suggest that the children with spastic diplegic cerebral palsy may have difficulties in resolving intersensory conflicts for maintenance of standing balance, or the demands of motor control in sensory conflict conditions outweigh the motor ability of children with spastic diplegic cerebral palsy.

The myofascial trigger point region: correlation between the degree of irritability and the prevalence of endplate noise.

Kuan T-S, Hsieh Y-L, Chen S-M, Chen J-T, Yen W-C, Hong C-Z: The myofascial trigger point region: correlation between the degree of irritability and the prevalence of endplate noise. Am J Phys Med Rehabil 2007;86:183–189. Objective: This study was designed to investigate the correlation between the irritability of the myofascial trigger point (MTrP) and the prevalence of endplate noise (EPN) in the MTrP region of human skeletal muscle. Design: Twenty normal subjects with latent MTrPs and 12 patients with active MTrPs in the upper trapezius muscles were recruited for this study. The patients reported the subjective pain intensity of the active MTrP (0–10). The MTrP and an adjacent non-MTrP site were confirmed and marked for the measurement of pressure pain threshold (with a pressure algometer) and the prevalence of EPN (with electromyographic recordings). Results: The prevalence of EPN in the MTrP regions was significantly higher (P < 0.01) in the active MTrPs than in the latent ones. However, no EPN could be found in the non-MTrP region near either the active or the latent MTrPs. The pain intensity and the pressure pain threshold were highly correlated with the prevalence of EPN in the MTrP region (r = 0.742 and −0.716, respectively). Conclusions: The irritability of an MTrP is highly correlated with the prevalence of EPN in the MTrP region of the upper trapezius muscle. The assessment of EPN prevalence in an MTrP region may be applied to evaluate the irritability of that MTrP.

Referred pain elicited by palpation and by needling of myofascial trigger points: A comparison

OBJECTIVE To investigate the occurrence of referred pain (ReP) elicited by palpation (Pal-ReP) or by needle injection (Inj-ReP) of myofascial trigger point (MTrP), and to assess the correlated factors, including the pain intensity of an active MTrP and the occurrence of local twitch response (LTR). DESIGN Correlational study. PATIENTS Ninety-five patients who were treated with MTrP injections. INTERVENTION MTrP injections. MAIN OUTCOME MEASURE Pain intensity of MTrP and occurrence of Pal-ReP, Inj-ReP, and LTR. RESULTS Both Pal-ReP and Inj-ReP were elicited in 53.9% of MTrPs, Inj-ReP, but not Pal-ReP, was elicited in 33.7% of MTrPs. Both Pal-ReP and Inj-ReP were unobtainable in 12.3% of MTrPs. The occurrence of ReP was significantly correlated to the pain intensity of active MTrP and the occurrence of LTR. CONCLUSION ReP could be elicited more frequently by needling than by palpation. The frequency of occurrence in ReP mainly depends on pain intensity of an active MTrP.