Effects of Trigger Point Dry Needling on Strength Measurements and Activation Levels of the Gluteus Medius: A Quasi-Experimental Randomized Control Study.

Background: Latent trigger points have been identified as a source of impaired muscle function giving rise to a reduction in force production and alterations in muscle activation patterns and movement efficiency. There is limited investigation into the effectiveness of a treatment in reducing these clinical manifestations. Purpose: To investigate whether the application of trigger point dry needling (TDN) to latent trigger points within the gluteus medius musculature affected strength measurements and muscle activation levels immediately following intervention. Design: Quasi experimental, single group, pretest-posttest, randomized control study. Methods: A control and an intervention side were randomly assigned for each participant (N = 39). Hand held dynamometer (HHD) force measurements and raw surface electromyography (sEMG) amplitude readings were recorded during maximal volitional isometric contractions of the gluteus medius in two separate positions before and after application of TDN. Comparison of within and between group data were conducted. Results: A statistically significant interaction between time (pre-TDN to post-TDN) and groups (intervention side and control side), p < 0.001 was found for HHD measurements in both positions. Post hoc analysis revealed a statistically significant difference (p < 0.001) for all comparisons in the side lying neutral (SL0) position, while statistically significant differences (p < 0.001) were found for pre and post-TDN measurements within intervention side as well as between the intervention and control side for post-TDN measurements in the side lying internal rotation (SLIR) position. For sEMG amplitude measurements, statistically significant differences were found only in the SL0 position for within group comparisons on the intervention side (p = 0.009) and for between group comparisons for post-TDN measurements (p = 0.002). Conclusion: Application of TDN to latent trigger points within the gluteus medius can significantly increase gluteus muscle force production immediately following intervention while reducing the level of muscle activation required during contraction. Level of Evidence: Level 2.

Hip abduction machine is better than free weights to target the gluteus medius while minimizing tensor fascia latae activation.

INTRODUCTION: Changes in the lower extremities' biomechanics are associated with gluteus medius (GMed) weakness and increased tensor fascia latae (TFL) activation. OBJECTIVE: To determine which exercises produce greater GMed activity while minimizing TFL activation during the concentric and eccentric phases of three single-joint strengthening exercises. DESIGN: Controlled laboratory study. SETTING: Laboratory. PARTICIPANTS: Eleven males (age: 29.18 ± 4.51 years; body mass: 84.01 ± 14.48 kg; height: 1.74 ± 0.07 m; body fat: 16.34 ± 3.33%). MAIN OUTCOME MEASURES: GMed and TFL activation and activation ratio while performing ten maximal repetitions of three exercises: side-lying hip abduction (SLHA); clamshell (CLAM) and hip abductor machine (HAM). RESULTS: GMed activation was greater than TFL in all exercises in both concentric and eccentric phases. There were no differences in GMed activation between the three exercises in both phases. TFL activation was greater in SLHA compared to HAM and CLAM during both phases. In both concentric and eccentric phases, GMed:TFL ratio was greater in HAM compared to CLAM and SLHA. CONCLUSIONS: GMed had increased activation compared to TFL in all analyzed exercises. Considering GMed:TFL ratio, if the goal is to preferentially activate GMed while minimizing TFL activation, the hip abductor machine seems to be the best exercise.

The Effect of Gluteus Medius Dry Needling on Pain and Physical Function of Non-athlete women with Unilateral Patellofemoral Pain Syndrome: A Double-Blind Randomized Clinical Trial.

BACKGROUND: One of the most common knee problems is patellofemoral pain syndrome (PFPS). It is of great importance to pay attention to the muscles of the hip area in people with PFPS, especially to the presence of trigger points within the gluteus medius (GM). Accordingly, using therapeutic interventions to eliminate trigger points is required. Therefore, the aim of the present study was to evaluate the effect of GM active trigger point dry needling (TrP-DN) on pain and physical function of non-athlete women with unilateral PFPS. METHODS: 29 young non-athlete women aged between 17 and 40 years old with unilateral PFPS were randomly divided into two groups of experimental (n = 15) and control (n = 14) through the simple and convenience sampling method. Both groups received conventional physiotherapy twice a week up to 6 sessions. The experimental group also received GM active TrP-DN once a week for 3 sessions in addition to the conventional physiotherapy. Pain intensity and physical function of women with PFPS were measured in both groups in three stages of before, immediately after and one week after performing the treatment sessions. FINDINGS: The six-session physiotherapy treatment led to a significant reduction in pain intensity as well as an improvement in physical function in both groups (p < 0.001). In addition, the intergroup comparison showed a significant improvement in physical function of the experimental group after one week from the GM active TrP-DN, compared to the control group (p = 0.048). CONCLUSION: The present study indicated that conventional physiotherapy with or without GM active TrP-DN can reduce pain and improve physical function in non-athlete women with unilateral PFPS. This study also revealed that conventional physiotherapy combined with dry needling can lead to further reduction in pain and a greater improvement in physical function of this group of patients.

The relationship between gluteus medius latent trigger point and muscle strength in healthy subjects.

INTRODUCTION: We hypothesized that latent MTrPs might decrease gluteus medius muscle strength in healthy individuals. This study aimed to investigate the relationship between latent MTrPs and gluteus medius muscle strength in a group of healthy adults. METHODS: Forty-eight healthy men were included in the study. Trigger point examination for the gluteus medius was performed bilaterally. Subjects with one or more trigger points on the dominant side and those without any trigger point were assigned to two groups. Muscle strength for the gluteus medius was assessed with a manual muscle tester using the "break test" technique on both sides. For statistical analysis, the independent sample t-test was used to compare the intergroup differences. RESULTS: The latent MTrP group demonstrated lower abduction muscle strength in the dominant gluteus medius. Moreover, the latent MTrP group showed higher abduction muscle strength in the non-dominant gluteus medius (p < 0.05). Intergroup comparison revealed that gluteus medius abduction muscle strength on the dominant side was higher in the non-latent MTrP group (p < 0.05). CONCLUSION: Latent MTrP may cause joint movement limitation, overload by affecting motor activation patterns and reciprocal inhibition mechanisms. Outcomes of the current study revealed that gluteus medius abduction strength values below 9.7 kg could be associated with latent MTrP with high sensitivity and low specificity. It is imperative to note that the latent MTrP of gluteus medius muscle, which has a critical role in the lumbopelvic junction, should not be ignored in clinical practice, and treatment should be applied when detected.

Simultaneous ice and transcutaneous electrical nerve stimulation decrease anterior knee pain during running but do not affect running kinematics or associated muscle inhibition.

BACKGROUND: Runners often experience anterior knee pain and this pain is associated with altered running neuromechanics. The purpose of this study was to examine potential therapeutic benefits (reduced pain and restored running neuromechanics) of simultaneously applied ice and transcutaneous electrical nerve stimulation on experimentally-induced anterior knee pain. METHODS: Nineteen healthy subjects completed a sham and treatment data collection session. For both sessions, hypertonic saline was infused into the infrapatellar fat pad for approximately 80 min to induce experimental anterior knee pain. Perceived pain levels were measured every two minutes and running neuromechanics were recorded at four time points: pre-pain, pain before treatment, pain immediately post-treatment, and pain 20 min post-treatment. FINDINGS: The saline infusion significantly increased perceived knee pain from 0 to 2.8 cm. The ice/transcutaneous electrical nerve stimulation treatment significantly reduced perceived knee pain by 35%, six minutes after the treatment initiation. Perceived knee pain remained reduced until eight minutes after the treatment termination. The knee pain significantly decreased peak gluteus medius, vastus lateralis, and vastus medialis activation during running, each by an average of 17% plus/minus 6%; however, none of these decreases were resolved via the therapeutic treatment. Neither the knee pain nor the therapeutic treatment significantly affected peak gluteus maximus activation or peak hip adduction angle. INTERPRETATION: The experimental pain model effectively produced anterior knee pain and decreased muscle activation during running. The simultaneous ice/transcutaneous electrical nerve stimulation treatment effectively decreased anterior knee pain, but did not restore running neuromechanics that were altered due to the pain.

Effects of real-time visual biofeedback of pelvic movement on electromyographic activity of hip muscles and lateral pelvic tilt during unilateral weight-bearing and side-lying hip abduction exercises.

Although neutral pelvic alignment is important for hip abduction exercises, studies exploring objectively monitored pelvic alignment on the gluteus medius (Gmed) muscle activity during hip abduction exercises, especially under weight-bearing (WB) conditions, are limited. Therefore, we examined the effects of real-time visual biofeedback (RVBF) of pelvic movement on electromyographic (EMG) activity of hip muscles and lateral pelvic tilt during unilateral WB and side-lying hip abductions. Fifteen male participants performed unilateral WB and side-lying hip abduction exercises with and without RVBF. Under the RVBF condition, participants monitored pelvic movements in real time during hip abduction exercises. EMG activity of Gmed and quadratus lumborum (QL) as well as lateral pelvic tilt angle were recorded during each hip abduction exercise. Gmed EMG activity increased, while lateral pelvic tilt decreased during both hip abduction exercises with RVBF (p < 0.05). Additionally, the changes in Gmed activity, the Gmed/QL activity ratio, and the lateral pelvic tilt angle under RVBF were greater during unilateral WB hip abduction than during side-lying hip abduction (p < 0.05). These results suggest that RVBF of pelvic movement could be useful to strengthen Gmed and prevent compensatory lateral pelvic movement during hip abduction exercises, especially in the unilateral WB position.

Surgical treatment of middle cluneal nerve entrapment neuropathy: technical note.

OBJECTIVE The etiology of low-back pain (LBP) is heterogeneous and is unknown in some patients with chronic pain. Superior cluneal nerve entrapment has been proposed as a causative factor, and some patients suffer severe symptoms. The middle cluneal nerve (MCN) is also implicated in the elicitation of LBP, and its clinical course and etiology remain unclear. The authors report the preliminary outcomes of a less invasive microsurgical release procedure to address MCN entrapment (MCN-E). METHODS The authors enrolled 11 patients (13 sites) with intractable LBP judged to be due to MCN-E. The group included 3 men and 8 women ranging in age from 52 to 86 years. Microscopic MCN neurolysis was performed under local anesthesia with the patient in the prone position. Postoperatively, all patients were allowed to walk freely with no restrictions. The mean follow-up period was 10.5 months. LBP severity was evaluated on the numerical rating scale (NRS) and by the Japanese Orthopaedic Association (JOA) and the Roland-Morris Disability Questionnaire (RDQ) scores. RESULTS All patients suffered buttock pain, and 9 also had leg symptoms. The symptoms were aggravated by standing, lumbar flexion, rolling over, prolonged sitting, and especially by walking. The numbers of nerve branches addressed during MCN neurolysis were 1 in 9 patients, 2 in 1 patient, and 3 in 1 patient. One patient required reoperation due to insufficient decompression originally. There were no local or systemic complications during or after surgery. Postoperatively, the symptoms of all patients improved statistically significantly; the mean NRS score fell from 7.0 to 1.4, the mean RDQ from 10.8 to 1.4, and the mean JOA score rose from 13.7 to 23.6. CONCLUSIONS Less invasive MCN neurolysis performed under local anesthesia is useful for LBP caused by MCN-E. In patients with intractable LBP, MCN-E should be considered.

A porcine gluteus medius muscle genome-wide transcriptome analysis: dietary effects of omega-6 and omega-3 fatty acids on biological mechanisms.

BACKGROUND: The level of omega-6 and omega-3 polyunsaturated fatty acids can affect many cellular systems and function via nuclear receptors or the bioactive lipid regulation of gene expression. The objective of this study was to investigate changes in the muscle transcriptome and the biological functions regulated by increased consumption of omega-3 and omega-6 fatty acids in the pig gluteus medius muscle. RESULTS: The transcriptome of the gluteus medius muscle was studied for pigs subjected to either a control diet or a diet supplemented with linseed and rapeseed oil to increase polyunsaturated fatty acid content. Next-generation sequencing (NGS) was used to generate the muscle tissue transcriptome database pointing differentially expressed genes (DEG). Comparative expression analyses identified 749 genes significantly differing at least in the twofold of change between two groups of animals fed with divergent level of omega-3 and omega-6 fatty acids. The expression of 219 genes was upregulated, and the expression of 530 genes was downregulated in the group of pigs supplemented with omega-3 and omega-6 fatty acids in relation to control group pigs. Results of RNA-seq indicated a role of fatty acid in the regulation of the expression of genes which are essential for muscle tissue development and functioning. Functional analysis revealed that the identified genes were important for a number of biological processes including inflammatory response, signaling, lipid metabolism, and homeostasis. CONCLUSIONS: Summarizing, obtained results provide strong evidence that omega-6 and omega-3 fatty acids regulate fundamental metabolic processes in muscle tissue development and functioning.