Citations
To compare the effectiveness of extracorporeal shock wave therapy (ESWT) and trigger point injection (TPI) for the treatment of myofascial pain syndrome in the quadratus lumborum.
In a retrospective study at our institute, 30 patients with myofascial pain syndrome in the quadratus lumborum were assigned to ESWT or TPI groups. We assessed ESWT and TPI treatment according to their affects on pain relief and disability improvement. The outcome measures for the pain assessment were a visual analogue scale score and pain pressure threshold. The outcome measures for the disability assessment were Oswestry Disability Index, Roles and Maudsley, and Quebec Back Pain Disability Scale scores.
Both groups demonstrated statistically significant improvements in pain and disability measures after treatment. However, in comparing the treatments, we found ESWT to be more effective than TPI for pain relief. There were no statistically significant differences between the groups with respect to disability.
Compared to TPI, ESWT showed superior results for pain relief. Thus, we consider ESWT as an effective treatment for myofascial pain syndrome in the quadratus lumborum.
Citations
To report the characteristics of myofascial trigger points (MTrPs) in the infraspinatus muscle and evaluate the therapeutic effect of trigger-point injections.
Medical records of 297 patients (221 women; age, 53.9±11.3 years) with MTrPs in the infraspinatus muscle were reviewed retrospectively. Because there were 83 patients with MTrPs in both infraspinatus muscles, the characteristics of total 380 infraspinatus muscles with MTrPs (214 one side, 83 both sides) were investigated. Specific characteristics collected included chief complaint area, referred pain pattern, the number of local twitch responses, and distribution of MTrPs in the muscle. For statistical analysis, the paired t-test was used to compare a visual analogue scale (VAS) before and 2 weeks after the first injection.
The most common chief complaint area of MTrPs in the infraspinatus muscle was the scapular area. The most common pattern of referred pain was the anterolateral aspect of the arm (above the elbow). Active MTrPs were multiple rather than single in the infraspinatus muscle. MTrPs were frequently in the center of the muscle. Trigger-point injection of the infraspinatus muscle significantly decreased the pain intensity. Mean VAS score decreased significantly after the first injection compared to the baseline (7.11 vs. 3.74; p<0.001).
Characteristics of MTrPs and the therapeutic effects of trigger-point injections of the infraspinatus muscle were assessed. These findings could provide clinicians with useful information in diagnosing and treating myofascial pain syndrome of the infraspinatus muscle.
Citations
To investigate the comparative treatment effects of ultrasound-guided pulsed radiofrequency treatment (UG-PRF) in the gastrocnemius interfascial space and ultrasound-guided interfascial injection (UG-INJ) on myofascial pain syndrome.
Forty consecutive patients with myofascial pain syndrome of the gastrocnemius were enrolled and were allocated to one of the two groups. Twenty patients were treated by UG-PRF delivered to the gastrocnemius interfascial space (UG-PRF group) and the other 20 patients were treated by interfascial injection (UG-INJ group). The primary outcome measure was the numeric rating score (NRS) for pain on pressing the tender point in the gastrocnemius, and the secondary outcome measure was health-related quality of life as determined by the Short Form-36 questionnaire (SF-36). NRSs were obtained at the first visit, immediately after treatment, and at 2 and 4 weeks post-treatment, and physical component summary scores (PCS) and mental component summary scores (MCS) of the SF-36 questionnaire were measured at the first visit and at 4 weeks post-treatment.
Immediately after treatments, mean NRS in the UG-PRF group was significantly higher than that in the UG-INJ group (p<0.0001). However, at 2 and 4 weeks post-treatment, the mean NRS was significantly lower in the UG-PRF group (both p<0.0001). Similarly, at 4 weeks post-treatment, mean PCS and MCS were significantly higher in the UG-PRF group (p<0.0001 and p=0.002, respectively).
Based on these results, the authors conclude that ultrasound-guided gastrocnemius interfascial PRF provides an attractive treatment for myofascial pain syndrome of the gastrocnemius.
Citations
To assess head posture using cervical spine X-rays to find out whether forward head posture is related to myofascial pain syndrome (MPS) in neck and shoulder.
Eighty-eight participants who were diagnosed with MPS in neck and shoulder were evaluated in this study. Four parameters (distance among head, cervical spines, and shoulder, and cervical angle) were measured from lateral view of cervical spine X-ray. The location and number of trigger points in the neck and shoulder and symptom duration were evaluated for each patient.
Both horizontal distances between C1 vertebral body and C7 spinous process and between the earhole and C7 vertebral body were negatively correlated with cervical angle reflecting cervical lordosis (p<0.05). Younger patients had significantly (p<0.05) less cervical angle with more forward head posture. There was no relationship between MPS (presence, location, and number of trigger points) and radiologic assessments (distance parameters and the cervical angle).
Forward head posture and reduced cervical lordosis were seen more in younger patients with spontaneous neck pain. However, these abnormalities did not correlate with the location or the number of MPS. Further studies are needed to delineate the mechanism of neck pain in patients with forward head posture.
Citations
To determine overall handgrip strength (HGS), we assessed the short-term change of HGS after trigger point injection (TPI) in women with muscular pain in the upper extremities by comparison with established pain scales.
The study enrolled 50 female patients (FMS with MPS group: 29 patients with combined fibromyalgia [FMS] and myofascial pain syndrome [MPS]; MPS group: 21 patients with MPS) who presented with muscular pain in the upper extremities at Konyang University Hospital. In addition, a total of 9 healthy women (control group) were prospectively enrolled in the study. We surveyed the three groups using the following established pain scales: the Fibromyalgia Impact Questionnaire (FIQ), the 36-Item Short Form Health Survey (SF-36), and the Short Form McGill Pain Questionnaire (MPQ). HGS was measured in both hands of study participants using a handgrip dynamometer. We performed TPI (0.5% lidocaine, total 10 mL, injected at the pain site of upper extremities). After 20 minutes, we remeasured the patient's HGS and MPQ score.
ANOVA analysis was conducted among groups. Based on Tukey multiple comparison test, the majority of FIQ and SF-36 subscales, total FIQ and SF-36 scores, MPQ and HGS were significantly different between FMS with MPS and the other groups. There was no statistically significant difference between MPS and control groups. Higher HGS was positively associated with enhanced physical function, negatively associated with total FIQ and MPQ scores, and positively associated with the total SF-36 score calculated using Spearman correlation. Post-TPI MPQ decreased and HGS increased. In patient groups, a negative correlation was found between MPQ and HGS.
The HGS test might potentially be a complementary tool in assessing the short-term treatment effects of women with muscular pain in the upper extremities.
Citations
To investigate an appropriate depth of needle insertion during trigger point injection into the rhomboid major muscle.
Sixty-two patients who visited our department with shoulder or upper back pain participated in this study. The distance between the skin and the rhomboid major muscle (SM) and the distance between the skin and rib (SB) were measured using ultrasonography. The subjects were divided into 3 groups according to BMI: BMI less than 23 kg/m2 (underweight or normal group); 23 kg/m2 or more to less than 25 kg/m2 (overweight group); and 25 kg/m2 or more (obese group). The mean±standard deviation (SD) of SM and SB of each group were calculated. A range between mean+1 SD of SM and the mean-1 SD of SB was defined as a safe margin.
The underweight or normal group's SM, SB, and the safe margin were 1.2±0.2, 2.1±0.4, and 1.4 to 1.7 cm, respectively. The overweight group's SM and SB were 1.4±0.2 and 2.4±0.9 cm, respectively. The safe margin could not be calculated for this group. The obese group's SM, SB, and the safe margin were 1.8±0.3, 2.7±0.5, and 2.1 to 2.2 cm, respectively.
This study will help us to set the standard depth of safe needle insertion into the rhomboid major muscle in an effective manner without causing any complications.
Citations
To investigate the effects of trigger point injection with or without ischemic compression in treatment of myofascial trigger points in the upper trapezius muscle.
Sixty patients with active myofascial trigger points in upper trapezius muscle were randomly divided into three groups: group 1 (n=20) received only trigger point injections, group 2 (n=20) received trigger point injections with 30 seconds of ischemic compression, and group 3 (n=20) received trigger point injections with 60 seconds of ischemic compression. The visual analogue scale, pressure pain threshold, and range of motion of the neck were assessed before treatment, immediately after treatment, and 1 week after treatment. Korean Neck Disability Indexes were assessed before treatment and 1 week after treatment.
We found a significant improvement in all assessment parameters (p<0.05) in all groups. But, receiving trigger point injections with ischemic compression group showed significant improvement as compared with the receiving only trigger point injections group. And no significant differences between receiving 30 seconds of ischemic compression group and 60 seconds of ischemic compression group.
This study demonstrated the effectiveness of ischemic compression for myofascial trigger point. Trigger point injections combined with ischemic compression shows better effects on treatment of myofascial trigger points in the upper trapezius muscle than the only trigger point injections therapy. But the duration of ischemic compression did not affect treatment of myofascial trigger point.
Citations
To investigate the effect of extracorporeal shock wave therapy (ESWT) on myofascial pain syndrome (MPS).
Thirty patients with MPS in trapezius muscle were randomly divided into two groups, ESWT group (n=15), and trigger point injections (TPI)+transcutaneous electrical nerve stimulation (TENS) group (n=15). For a total of 3 weeks, ESWT was undertaken with 1,500 pulse each time at one week interval totaling 4,500 pulse, TPI for once a week totaling three times and TENS for five times a week totaling three weeks.
The changes in pain threshold (lb/cm2) showed the values of 6.86±1.35 before first therapy, 11.43±0.27 after first therapy, and 12.57±0.72 after third therapy, while TPI+TENS group showed the values of 6.20±1.92 before first therapy, 8.80±0.48 after first therapy, and 9.60±2.19 after third therapy, and the changes between the groups were significantly different (p=0.045). The changes in visual analog scale were estimated to be 6.86±0.90 before first therapy, 2.86±0.90 after first therapy, and 1.86±0.69 after third therapy in case of ESWT group, whereas the figures were estimated to be 7.20±1.30 before first therapy, 4.60±0.55 after first therapy, and 2.80±0.84 after third therapy in case of TPI+TENS group, and the changes between the groups were significantly different (p=0.010). The changes in McGill pain questionnaire (p=0.816) and pain rating scale (p=0.644) between the groups were not significantly different. The changes in neck ROM were also not significantly different between the groups (p>0.05).
The ESWT in patients with MPS in trapezius muscle are as effective as TPI and TENS for the purpose of pain relief and improving cervical range of motion.
Citations
Objective: The diagnosis of myofascial pain syndrome (MPS) is commonly made by Simons' clinical diagnostic criteria which is mainly based on patients' complaints, so it is difficult to distinguish from malingering. The purpose of this study is to evaluate local twitch response by needling (LTR) as an objective diagnostic criterion of MPS.
Method: Forty four industrial designers complaining of regional pain in neck, shoulder, or upper arm were examined by a physiatrist. If trigger point was detected, local twitch response by needling was confirmed and than severity was measured by 4 grades. Sensitivity, specificity, and positive predictive value of local twitch response was calculated with diagnosis made by Simons' clinical diagnostic criteria. Correlation between grade of local twitch response and sum of clinical features in Simons' criteria was also evaluated.
Results: Local twitch response by needling was corresponding with the diagnosis of MPS by Simons' criteria (sensitivity 100%, specificity 96.7%, positive predictive value 93.3%), and the severity of local twitch response was significantly associated with sum of clinical features in Simons' criteria (Spearman correlation 0.950; p=0.048)
Conclusion: Local twitch response by needling is an important and objective diagnostic criterion of MPS.
Objective: The purpose of this study is to evaluate the effects of cold air application on the pressure threshold of myofascial trigger points.
Method: The 60 patients with myofascial trigger points in unilateral infraspinatus muscle were divided into 3 groups with equal number and cold air was applied using CRAis (Kyung-won Century, Korea) for 1, 3 and 5 minutes. We examined the changes of pressure threshold in myofascial trigger points before, immediately after and 30 minutes after cold air application. Also we examined the changes of pressure threshold of contralateral infraspinatus muscles.
Results: 1) The pressure threshold of trigger point in infraspinatus muscle were increased immediately and 30 minutes after the cold air application as assessed by the pressure algometer (p<0.05).
2) There was no significant correlations in the changes of pressure threshold among 3 groups after the cold air application (p>0.05).
3) There was no significant correlations among the age, the body mass index and the changes of pressure threshold in myofascial trigger points (p>0.05).
Conclusion: We conclude that the cold air application is a effective method for treatment of myofascial trigger points.
Myofascial trigger point(TP) is characterized as an impaired energy metabolism. We hypothesized that the use of dextrose as an energy supplement for TP injection would be more effective than saline or lidocaine. Sixty four typical myofascial pain patients were treated with TP injections. Among them 23 were injected with 5% dextrose water(D/W Group), 20 with normal saline (N/S Group), and 21 with 0.5% lidocaine (Lidocaine Group). Visual analogue scale(VAS) and pressure threshold algometer(kg/cm2) were used as measuring tools before, immediately after, and 7 days after the injection therapies. Mean VAS scores were 6.78 before, 5.19 immediately after, and 3.39 seven days after the injections, and the treatment effects were greater after the second and third injections. Mean differences of pressure threshold were 0.37 before and immediately after injections, and 0.42 before and 7 days after injections. Significant elevation of threshold was noted after the second and third injections. Mean VAS were not significantly different in three groups before and immediately after injections. But after 7 days, only D/W Group showed significantly lower score of 2.39, compared to 3.85 in N/S Group and 4.05 in Lidocaine Group(P<0.01). Mean pressure threshold before and immediately after injections was not different in each group. After seven days D/W Group also showed significantly higher value of 2.49, compared to 1.91 in N/S Group and 2.07 in Lidocaine Group(P<0.05). We have concluded that 5% dextrose water would be the preferable choice for TP injection.
Objective: The purpose of this study is to evaluate the effects of a self-stretching exercise on the pressure threshold of myofascial trigger point.
Method: We examined the changes of pressure threshold in 66 patients with myofascial trigger points before and after a self-stretching exercise of shoulder girdle and also tested the visual analogue scale (VAS) of the subjective pain intensity. The self-stretching exercise of shoulder girdle includes a stretching exercise of four muscles in shoulder girdle simultaneously, including upper trapezius, levator scapulae, infraspinatus, rhomboideus major and minor, which is followed by 1) a sitting position, relaxed, 2) lateral bending of neck to contralateral side, 3) forward and downward stretching of ipsilateral arm with protrusion of scapula and internal rotation of arm maximally to the contralateral foot. Each stretching motion is maintained for 30 seconds.
Results: The results of the patients experiencing unilateral or bilateral myofascial neck and shoulder pain showed that the pressure threshold of trigger point increased in response to the self-stretching exercise as assessed by a pressure algometer. Also visual analogue scale (VAS) decreased in response to the self-stretching exercise.
Conclusion: We conclude that the self-stretching exercise of shoulder girdle is an effective method for the simultaneous stretching of upper trapezius, levator scapulae, infraspinatus, rhomboideus major and minor.
Treatment of the trigger points(TrP) is the most important thing for management of myofascial pain syndrome(MPS). The most effective treatment of TrP is local injection with various types of drug or dry needling, but the effectiveness of each drug was not the same by each investigator. The purposes of this study are to evaluate diagnostic value of Digital Infrared Thermographic Imaging(DITI) for trigger points and therapeutic effects of lidocaine and normal saline by DITI. This study included 15 patients who have TrP on upper trapezius muscles as a patient group and 10 normal adults as a control group. 2 cc of 2% Lidocaine was injected to the TrP of upper trapezius muscles in a patient group and to one side of upper trapezius muscles in a control group. One week after the first injection, 2 cc of normal saline was injected by the same method in a patient group. DITI was taken sequentially, preinjection(Pre), immediately after injection(P0), 15(P15), 30(P30), 60(P60) minutes and 24 hours(P24h) after injection. The parameters, temperature difference(ԤT) of both sides, changes of ԤT(ԤdT), visual analogue scale(VAS) were recorded at each point. It was considered abnormal, when the ԤT was above 0.6oC. The patient group was subdivided as Group I(hot spot), Group II(cold spot) and Group III(no difference) according to preinjection thermographic findings of TrP. The results were as follows: 1) ԤT of control group was within 0.52oC(95% confidence interval), 2) the numbers were 9 in Group I, 3 in Group II and 3 in Group III, and the sensitivity and specificity of hot spots for MPS were 81.8% and 57.1%, respectively, 3) ԤT was more reduced after lidocaine- than normal saline-injection, 4) VAS was more reduced after lidocaine- than normal saline-injection, especially in Group I and II. It is concluded that DITI can be used as one of the diagnostic tools for TrP and lidocaine is more effective than normal saline for the treatment of TrP.
Since the myofascial trigger point(MFTrP) has been described fifty years ago, its underlying pathophysiology has been remained unclear. The diagnosis also depends on the characteristic pain, tenderness and physical findings, which is very subjective. In recent years, some physicians investigated the objective findings of MFTrP, using the pressure algo meter and thermography. We investigated the electromyographic findings of MFTrP to evaluate the clinical usefulness of local twitch response(LTR) and sympathetic skin response(SSR), and to evaluate the electrophysiologic characteristics of MFTrP.
21 patients, diagnosed as myofascial trigger point syndrome on upper trapezius and so on, were evaluated for the triggering pain with visual analog scale(VAS), pressure threshold(THpr) using pressure algometer(Dolorimeter), LTR with concentric needle electrode and SSR on the palm. There was a significant negative correlation between VAS and THpr, but no significant correlation with electromyographic findings of LTR. Thus LTR could support the existence of MFTrP electrod iagnostically, but, could not explain the clinically correlated severity of MFTrP. There were only 3 patients showing abnormal SSR, who were all complaining the sympathetic symptoms on the affected arm with reffered pain. Even though referred pain to arm and hand existed, SSR was normal because suggested autonomic dysfunction of MFTrP is localized mechanism.
Among the 13 patients underwent the trigger point block, 8 patients who showed no residual LTR immediate after MFTrP block, had a great symptomatic improvement of MFTrP in a week, but 5 patients who showed the residual LTR did not. Regardless of complaint of pain and soreness immediate after block, loss of LTR would be predicted as a good treatment result.
In some cases, spontaneous EMG activity exist within the 3-4mm sized focus of MFTrP, although the taut band of MFTrP is 3-4cm length and depth. But this focus of MFTrP is a electrophysiologic changes within a muscle, not a structural changes seen by ultrasonography.
Postherpetic neuralgia(PHN) is a common complication of herpes zoster and one of most common intractable conditions in pain clinics. The PHN is defined solely by the persistence of pain after the herpes zoster. There has been no known pathophysiology for the PHN and the role of scars, local muscles, tendons and ligaments has not been addressed.
The characteristics, duration, and location of the referred pain were evaluated along with the electromyographic(EMG) examination of involved muscles. Then treatment was given under the concept of a myofascial pain syndrome till the pain was completely resolved. Most of the patients with acute or chronic pain were relieved from the pain.
This study revealed a practical and important new concept on herpes zoster related pains. In some cases of herpes zoster, acute herpes zoster seems to be an initiating factor to form an acute trigger point in the muscles of the related area. And uncomplicated trigger points neglected in an acute stage become chronic intractable problems, when they were neglected.
In conclusion, myofascial pain syndrome should be taken into account when a postherpetic neuralgia is diagnosed. The recognition of this possible relationship between PHN and myofascial pain syndrome and an early proper care can greatly reduce the suffering of patents from chronic pain.