Gluteal Research Articles

Application of an artificial intelligence-based tool in [18F]FDG PET/CT for the assessment of bone marrow involvement in multiple myeloma

Purpose[18F]FDG PET/CT is an imaging modality of high performance in multiple myeloma (MM). Nevertheless, the inter-observer reproducibility in PET/CT scan interpretation may be hampered by the different patterns of bone marrow (BM) infiltration in the disease. Although many approaches have been recently developed to address the issue of standardization, none can yet be considered a standard method in the interpretation of PET/CT. We herein aim to validate a novel three-dimensional deep learning-based tool on PET/CT images for automated assessment of the intensity of BM metabolism in MM patients.Materials and methodsWhole-body [18F]FDG PET/CT scans of 35 consecutive, previously untreated MM patients were studied. All patients were investigated in the context of an open-label, multicenter, randomized, active-controlled, phase 3 trial (GMMG-HD7). Qualitative (visual) analysis classified the PET/CT scans into three groups based on the presence and number of focal [18F]FDG-avid lesions as well as the degree of diffuse [18F]FDG uptake in the BM. The proposed automated method for BM metabolism assessment is based on an initial CT-based segmentation of the skeleton, its transfer to the SUV PET images, the subsequent application of different SUV thresholds, and refinement of the resulting regions using postprocessing. In the present analysis, six different SUV thresholds (Approaches 1–6) were applied for the definition of pathological tracer uptake in the skeleton [Approach 1: liver SUVmedian × 1.1 (axial skeleton), gluteal muscles SUVmedian × 4 (extremities). Approach 2: liver SUVmedian × 1.5 (axial skeleton), gluteal muscles SUVmedian × 4 (extremities). Approach 3: liver SUVmedian × 2 (axial skeleton), gluteal muscles SUVmedian × 4 (extremities). Approach 4: ≥ 2.5. Approach 5: ≥ 2.5 (axial skeleton), ≥ 2.0 (extremities). Approach 6: SUVmax liver]. Using the resulting masks, subsequent calculations of the whole-body metabolic tumor volume (MTV) and total lesion glycolysis (TLG) in each patient were performed. A correlation analysis was performed between the automated PET values and the results of the visual PET/CT analysis as well as the histopathological, cytogenetical, and clinical data of the patients.ResultsBM segmentation and calculation of MTV and TLG after the application of the deep learning tool were feasible in all patients. A significant positive correlation (p < 0.05) was observed between the results of the visual analysis of the PET/CT scans for the three patient groups and the MTV and TLG values after the employment of all six [18F]FDG uptake thresholds. In addition, there were significant differences between the three patient groups with regard to their MTV and TLG values for all applied thresholds of pathological tracer uptake. Furthermore, we could demonstrate a significant, moderate, positive correlation of BM plasma cell infiltration and plasma levels of β2-microglobulin with the automated quantitative PET/CT parameters MTV and TLG after utilization of Approaches 1, 2, 4, and 5.ConclusionsThe automated, volumetric, whole-body PET/CT assessment of the BM metabolic activity in MM is feasible with the herein applied method and correlates with clinically relevant parameters in the disease. This methodology offers a potentially reliable tool in the direction of optimization and standardization of PET/CT interpretation in MM. Based on the present promising findings, the deep learning-based approach will be further evaluated in future prospective studies with larger patient cohorts.

Magnetic resonance imaging findings of the lower limb muscles in anti-mitochondrial M2 antibody-positive myositis

Anti-mitochondrial M2 antibody (AMA-M2)-positive myositis is an idiopathic inflammatory myopathy (IIM). Of all patients with myositis, 2.5–19.5% have AMA-M2 antibodies. However, the detailed distribution of muscles affected in AMA-positive myositis is unknown. Therefore, we examined lower muscle magnetic resonance imaging (MRI) findings of patients with AMA-positive myositis. Among the 63 patients with IIM at our institute, 5 (7.9%) were positive for AMA-M2 antibodies. However, one was also positive for anti-Jo1 antibodies; therefore, four patients were finally participated in this study. All patients had high-intensity MRI signals in the proximal muscles, including the gluteus maximus and iliopsoas muscles, and in the thigh muscles, including the vastus lateralis, vastus medialis, adductor magnus, and semimembranosus muscles. Lower leg muscles were relatively spared. Fascial edema was observed in all patients and was also present in the lower leg muscles. Subcutaneous edema was observed, particularly in the proximal portion of the lower limbs. In AMA-positive myositis, proximal muscles, including the gluteus maximus, vastus lateralis, adductor magnus, and the semimembranosus, were markedly affected, while the lower leg muscles were relatively preserved. Additionally, fascial edema was evident even in lower leg muscles. Therefore, muscle MRI can be a useful diagnostic aid for AMA-positive myositis.

Lower extremity muscle volume in females with patellofemoral pain and its relationships to hip and knee torque: A cross-sectional study

ObjectivesCompare lower extremity muscle volume in females with patellofemoral pain (PFP) to a cohort of pain-free females and investigate the relationship between thigh and hip muscle volume and torque. DesignCross-sectional. ParticipantsTwenty-one females, 13 with PFP and 8 pain-free controls. Main outcome measuresWe quantified normalized lower extremity muscle volume (cm3/kg*m) via magnetic resonance imaging and isometric hip and thigh torque (Nm/kg) via a multimodal dynamometer. ResultsVersus pain-free individuals, females with PFP had smaller muscle volume of the anterior hip (P < 0.019; d = 0.97–2.42), deep external rotators (P < 0.006; d = 1.0–3.93), hamstrings (P < 0.009; d = 1.09–2.12), rectus femoris (P < 0.001; d = 1.79), and vastus intermedius (P < 0.001; d = 1.88). There was no difference in muscle volume of the gluteus maximus (P = 0.311; d = 0.22), gluteus medius (P = 0.087; d = 0.87), vastus lateralis (P = 0.22; d = 0.39), and vastus medialis (P = 0.47; d = 0.04). Gluteus maximus volume was moderately correlated to hip abduction torque (r = 0.60; P = 0.03). Vasti muscles and semitendinosus volume were moderately correlated to knee extension (r = 0.57–0.69; P < 0.05) and flexion (r = 0.66; P = 0.01) torque, respectively. ConclusionFemales with PFP present with lesser thigh and hip muscle volumes, with variability in volumetric profiles across participants. Lower extremity knee extension and hip abduction strength are moderately associated with the vasti and gluteus maximus muscle volume, respectively.

A comprehensive study of skeletal muscle imaging in FHL1-related reducing body myopathy.

FHL1-related reducing body myopathy is an ultra-rare, X-linked dominant myopathy. In this cross-sectional study, we characterize skeletal muscle ultrasound, muscle MRI, and cardiac MRI findings in FHL1-related reducing body myopathy patients. Seventeen patients (11 male, mean age 35.4, range 12-76 years) from nine independent families with FHL1-related reducing body myopathy underwent clinical evaluation, muscle ultrasound (n = 11/17), and lower extremity muscle MRI (n = 14/17), including Dixon MRI (n = 6/17). Muscle ultrasound echogenicity was graded using a modified Heckmatt scale. T1 and STIR axial images of the lower extremity muscles were evaluated for pattern and distribution of abnormalities. Quantitative analysis of intramuscular fat fraction was performed using the Dixon MRI images. Cardiac studies included electrocardiogram (n = 15/17), echocardiogram (n = 17/17), and cardiac MRI (n = 6/17). Cardiac muscle function, T1 maps, T2-weighted black blood images, and late gadolinium enhancement patterns were analyzed. Muscle ultrasound showed a distinct pattern of increased echointensity in skeletal muscles with a nonuniform, multifocal, and "geographical" distribution, selectively involving the deeper fascicles of muscles such as biceps and tibialis anterior. Lower extremity muscle MRI showed relative sparing of gluteus maximus, rectus femoris, gracilis, and lateral gastrocnemius muscles and an asymmetric and multifocal, "geographical" pattern of T1 hyperintensity within affected muscles. Cardiac studies revealed mild and nonspecific abnormalities on electrocardiogram and echocardiogram with unremarkable cardiac MRI studies. Skeletal muscle ultrasound and muscle MRI reflect the multifocal aggregate formation in muscle in FHL1-related reducing body myopathy and are practical and informative tools that can aid in diagnosis and monitoring of disease progression.

The effect of mobile learning on safe ventrogluteal site injections: an interventional study

ABSTRACT&#x0D; Purpose: This study investigated whether a mobile learning program helped nurses give safer injections into the ventrogluteal site.&#x0D; Method: This interventional study was conducted between 20.08.2020 and 30.10.2020. The sample consisted of 34 nurses working at the adult units of a university hospital in a big city in Turkey. The study was approved by an ethics committee. Permission was obtained from the hospital. Informed consent was obtained from participants. Data were collected using a personal information form (pretest), the Ventrogluteal Area Knowledge Form (VAKF) (pretest and posttest), and the Training Effectiveness Evaluation Form (posttest). Participants watched an animation on their mobile phones for a week (intervention). The data were analyzed using the independent samples t-test and McNemar's test.&#x0D; Findings: Participants had a mean pretest and posttest VAKF score of 12.82±3.80 and 16.97±2.84, respectively (p&lt;0.05). After the intervention, most participants said "yes" to the statement, “The ventrogluteal site includes the gluteus medius and gluteus minimus muscles” (91.2%) (p&lt;0.05).&#x0D; Conclusion: The intervention helped nurses develop the cognitive skills necessary to administer safe injections into the ventrogluteal site.&#x0D; Implications for Nursing Practice: Mobile learning methods help nurses learn how to administer safe injections into the ventrogluteal site

Simulated Increase in Monoarticular Hip Muscle Strength Reduces the First Peak of Knee Compression Forces During Walking.

Reducing compressive knee contact forces (KCF) during walking could slow the progression and reduce symptoms of knee osteoarthritis. A previous study has shown that compensating for the hip flexion/extension moment could reduce the KCF peak occurring during early stance (KCFp1). Therefore, this study aimed to identify if monoarticular hip muscle could allow this compensation while considering different walking strategies. Gait trials from 24 healthy participants were used to make musculoskeletal models, and five load-cases were examined: (I) Normal, (II) with an applied external moment compensating for 100% of the hip flexion/extension moment, and (III-V) three conditions with isolated/combined 30% increase of peak isometric strength of gluteus medius and maximus. Knee contact forces, hip muscle forces, and joint moments were computed. A cluster analysis of the Normal condition was performed with hip and knee flexion/extension moment during KCFp1 as input to examine the influence of different walking strategies. The cluster analysis revealed two groups having significantly different hip and knee moments in early-stance (p < 0.01). The reduction in KCFp1 from the Normal condition, although present in both groups, was greater for the group with the highest hip and lowest knee flexion/extension moments for all conditions tested (II: -21.82 ± 8.71% versus -6.03 ± 6.68%, III: -3.21 ± 1.09% versus -1.59 ± 0.96%, IV: -3.00 ± 0.89% versus -1.76 ± 1.04%, V: -6.12 ± 1.69 versus -3.09 ± 1.95%). This reduction in KCFp1 occurred through a shift in force developed by the hamstrings during walking (biarticular) to the gluteus medius and maximus (monoarticular), whose isometric strength was increased. The differences between the groups suggest that this reduction depends on the walking strategy.

Automated Segmentation of Sacral Chordoma and Surrounding Muscles Using Deep Learning Ensemble

The manual segmentation of organ structures in radiation oncology treatment planning is a time-consuming and highly skilled task, particularly when treating rare tumors like sacral chordomas. This study evaluates the performance of automated deep learning (DL) models in accurately segmenting the gross tumor volume (GTV) and surrounding muscle structures of sacral chordomas. An expert radiation oncologist contoured 5 muscle structures (gluteus maximus, gluteus medius, gluteus minimus, paraspinal, piriformis) and sacral chordoma GTV on computed tomography images from 48 patients. We trained 6 DL auto-segmentation models based on 3-dimensional U-Net and residual 3-dimensional U-Net architectures. We then implemented an average and an optimally weighted average ensemble to improve prediction performance. We evaluated algorithms with the average and standard deviation of the volumetric Dice similarity coefficient, surface Dice similarity coefficient with 2- and 3-mm thresholds, and average symmetric surface distance. One independent expert radiation oncologist assessed the clinical viability of the DL contours and determined the necessary amount of editing before they could be used in clinical practice. Quantitatively, the ensembles performed the best across all structures. The optimal ensemble (volumetric Dice similarity coefficient, average symmetric surface distance) was (85.5 ± 6.4, 2.6 ± 0.8; GTV), (94.4 ± 1.5, 1.0 ± 0.4; gluteus maximus), (92.6 ± 0.9, 0.9 ± 0.1; gluteus medius), (85.0 ± 2.7, 1.1 ± 0.3; gluteus minimus), (92.1 ± 1.5, 0.8 ± 0.2; paraspinal), and (78.3 ± 5.7, 1.5 ± 0.6; piriformis). The qualitative evaluation suggested that the best model could reduce the total muscle and tumor delineation time to a 19-minute average. Our methodology produces expert-level muscle and sacral chordoma tumor segmentation using DL and ensemble modeling. It can substantially augment the streamlining and accuracy of treatment planning and represents a critical step toward automated delineation of the clinical target volume in sarcoma and other disease sites.

The effects of laminectomy surgery on pain, functional disability, sensitization and active trigger points in subjects with lumbar disc herniation

Objectives. To evaluate the effects of laminectomy surgery on pain, functional disability, sensitization and active trigger points in subjects with lumbar disc herniation.Methods. This study was a prospective pre‑post single group study. Seventy‑one patients (42 male and 29 female) have been enrolled in the research with an age range of 20–60 (48 ± 13.41). During 48 hours before surgery, patients were examined by a physiotherapist. Pain intensity were measured by visual analogue scale, disability by oswestry index (Persian version) and sensitivity level using pressure algometer. Three month after laminectomy, the patients were re‑examined for mentioned outcomes again.Results. The majority of the patients (23 cases, 32.4 %) revealed 3 active trigger points of the muscles before surgery. 60 subjects (84.5 %) experienced a gradual onset of leg pain without a trauma history. Lumbar multifidus (74.9 %), medial gastrocnemius (73.2 %), soleus (70.4) gluteus medius (62 %) were the most involved muscles with trigger points before laminectomy. On the other hand, after laminectomy medial gastrocnemius (54.9 %), lateral gastrocnemius (53.5 %), soleus (50.7 %), multifidus (39.4 %) and quadratus lumborum (39.4 %) were the most involved muscles with trigger points. The existence of trigger points in longissimus thoracis (p = 0.04), quadratus lumborum (p = 0.001), gluteus maximus (p = 0.04) and tibialis anterior (p = 0.02) were decreased significantly after laminectomy. Pain, disability and pain pressure threshold revealed significant differences before and after surgery.Discussion. The pattern of active trigger points of muscles was different before and after surgery. Multifidus and gastrocnemius were the most prevalent muscles with myofascial pain syndrome before and after surgery respectively.Conclusion. The present study revealed that pain, disability, number and prevalence of trigger points decreased after lumbar laminectomy. Nevertheless, pressure pain threshold of trigger points increased after surgery. The pattern of active trigger points of muscles was different before and after surgery. Multifidus and gastrocnemius were the most prevalent muscles with myofascial pain syndrome before and after surgery respectively. In fact, current results showed that active trigger points should be considered before and after laminectomy surgery

Deep Learning-Based Fully Automated Segmentation of Regional Muscle Volume and Spatial Intermuscular Fat Using CT

Rationale and ObjectivesWe aim to develop a CT-based deep learning (DL) system for fully automatic segmentation of regional muscle volume and measurement of the spatial intermuscular fat distribution of the gluteus maximus muscle. Materials and MethodsA total of 472 subjects were enrolled and randomly assigned to one of three groups: a training set, test set 1, and test set 2. For each subject in the training set and test set 1, we selected six slices of the CT images as the region of interest for manual segmentation by a radiologist. For each subject in test set 2, we selected all slices of the gluteus maximus muscle on the CT images for manual segmentation. The DL system was constructed using Attention U-Net and the Otsu binary thresholding method to segment the muscle and measure the fat fraction of the gluteus maximus muscle. The segmentation results of the DL system were evaluated using the Dice similarity coefficient (DSC), Hausdorff distance (HD), and the average surface distance (ASD) as metrics. Intraclass correlation coefficients (ICCs) and Bland-Altman plots were used to assess agreement in the measurements of fat fraction between the radiologist and the DL system. ResultsThe DL system showed good segmentation performance on the two test sets, with DSCs of 0.930 and 0.873, respectively. The fat fraction of the gluteus maximus muscle measured by the DL system was in agreement with the radiologist (ICC=0.748). ConclusionThe proposed DL system showed accurate, fully automated segmentation performance and good agreement with the radiologist at fat fraction evaluation, and can be further used for muscle evaluation.

Muscle ultrasound in patients with late-onset Pompe disease identified by newborn screening

ImportanceImplementation of newborn screening (NBS) in the United States now detects infants with late-onset Pompe disease (LOPD), a lysosomal storage disease characterized by slowly progressive muscle weakness, and detailed clinical evaluation has identified early muscle weakness. Biomarkers may be uninformative; thus, non-invasive imaging is needed to assess early LOPD muscle changes. Muscle ultrasound (US) measuring echointensity (EI) is a non-invasive measure of muscle health. ObjectiveIn this study, we aimed to evaluate if EI can identify characteristic patterns of muscle involvement in LOPD patients identified by NBS. Design/settingProspective, cross-sectional, single time point study. SettingOne-center study. ParticipantsWe examined 20 infants with NBS-identified LOPD (ages 5–20 months). All had standardized physical therapy assessments. ExposuresCreatine Kinase (CK) and Urine Hexose Tetrasaccharide (Glc4) were obtained. Muscle US of deltoid, biceps brachii, forearm flexors, thoracic paraspinals, gluteus maximus, quadriceps, tibialis anterior and medial gastrocnemius was performed. Main outcomes and measuresMean EI was calculated for all involved muscle groups. Quantitative EI Sum Scores were calculated as total EI divided by number of muscle groups assessed. We performed a comprehensive literature review to compare our results to previous LOPD muscle ultrasound studies. ResultsSix of 20 participants had elevated CK and 15 had ≥50% of the most common concerning kinematic physical findings; with normal urine Glc4 in all except one. Based upon muscle EI, the most affected muscles were quadriceps and medial gastrocnemius, with notable elevated EI in thoracic paraspinals. Biceps brachii was the most frequently affected upper extremity muscle. EI sum scores correlated moderately with increasing CK. Statistically significant positive correlation was found between posterior pelvic tilt in sitting and EI of gluteus maximus. Sonographic pattern of muscle involvement was similar to previous studies assessing older patients with LOPD. Conclusions and relevanceIn this study, muscle EI was elevated most often in the quadriceps, tibialis anterior, medial gastrocnemius, thoracic paraspinals, and biceps brachii. Involved muscles generally fit the profile of physical and muscle ultrasound/MRI exam findings in LOPD patients. Muscle ultrasound is recommended for rapid, focused muscle assessment in LOPD, especially those identified via NBS. Future studies should focus on this pattern of ultrasonographic abnormality and changes over time.

Investigation of Maximum Voluntary Contraction Activity during Robotic Gait

The purpose of this study is to investigate healthy people’s and patients’ lower extremity muscle activities during robotic gait using kinesiology analysis. Initially, muscle signals were taken from 6 paraplegic patients such as spinal cord injury (SCI) and stroke patients, 2 hemiplegic patients and 4 healthy persons. Then, signals were analyzed by using signal processing techniques such as filtering, rectifying, Root Mean Square (RMS) and also by calculating the Max Voluntary Contraction (MVC). As a result, it was seen that hip muscles such as the Gluteus Maximus (GMA), Gluteus Medius (GM) and Iliopsoas (ILP) had lower MVC values in the hemiplegic patients than those of the SCI patients and the healthy persons. Additionally, when the signals that were obtained were analyzed, it was found that the activity of the Medial Gastrocnemius (MG) muscle could be used in determination of movement path and movement intention. Moreover, the EMG results of gait motion may be helpful in applying accurate amplitude and frequency stimulation in epidural stimulation (ES) therapy.

Effect of the Aerobic and Resistance Training on Follistatin-Like 1 and Leukemia Inhibitory Factor Muscle Gene Expression in Rats Fed With a High-Fat Diet

Background: Follistatin-like 1 (FSTL-1) and leukemia inhibitory factor (LIF) are two myokines that are affected by overweight and have inflammatory and damaging effects. Considering that exercise reduces excess weight, this study aimed to evaluate the effect of aerobic and resistance training on FSTL-1 and LIF muscle gene expression in rats fed with a high-fat diet. Materials and Methods: In this experimental study, 32 rats were randomly divided into healthy control, obese control, obese+aerobic exercise, and obese+resistance exercise groups. The training was performed for 4 weeks at aerobic moderate intensity (50-65% VO2max). For resistance training, rats were also trained to climb the ladder (height 110 cm, slope 80%, and the distance between the bars of the ladder 2 cm), which is based on the determination of one repetition maximum. A high-fat diet was prepared with 40% fat, 13% protein, and 47% carbohydrates and continued until the rats reached the obesity range. The tissue sample was taken from the gluteus muscle. Results: The expression of FSTL-1 and LIF in the obese control group increased significantly compared to the healthy control group (P=0.044 and P=0.039, respectively). The expression of FSTL-1 and LIF in the resistance training group significantly decreased in comparison to the obese control group (P=0.049 and P=0.046, respectively). There was no significant difference between the aerobic exercise group and the obese control group (P=0.053 and P=0.059, respectively). However, a significant difference was observed between aerobic and resistance training groups in terms of FSTL-1 (P=0.042). Conclusion: Resistance exercise seems to have a greater and better effect on FSTL-1 and LIF in the muscles of obese samples compared to aerobic exercise.

The use of nonnormalized surface EMG and feature inputs for LSTM-based powered ankle prosthesis control algorithm development.

Advancements in instrumentation support improved powered ankle prostheses hardware development. However, control algorithms have limitations regarding number and type of sensors utilized and achieving autonomous adaptation, which is key to a natural ambulation. Surface electromyogram (sEMG) sensors are promising. With a minimized number of sEMG inputs an economic control algorithm can be developed, whereas limiting the use of lower leg muscles will provide a practical algorithm for both ankle disarticulation and transtibial amputation. To determine appropriate sensor combinations, a systematic assessment of the predictive success of variations of multiple sEMG inputs in estimating ankle position and moment has to conducted. More importantly, tackling the use of nonnormalized sEMG data in such algorithm development to overcome processing complexities in real-time is essential, but lacking. We used healthy population level walking data to (1) develop sagittal ankle position and moment predicting algorithms using nonnormalized sEMG, and (2) rank all muscle combinations based on success to determine economic and practical algorithms. Eight lower extremity muscles were studied as sEMG inputs to a long-short-term memory (LSTM) neural network architecture: tibialis anterior (TA), soleus (SO), medial gastrocnemius (MG), peroneus longus (PL), rectus femoris (RF), vastus medialis (VM), biceps femoris (BF) and gluteus maximus (GMax). Five features extracted from nonnormalized sEMG amplitudes were used: integrated EMG (IEMG), mean absolute value (MAV), Willison amplitude (WAMP), root mean square (RMS) and waveform length (WL). Muscle and feature combination variations were ranked using Pearson's correlation coefficient (r > 0.90 indicates successful correlations), the root-mean-square error and one-dimensional statistical parametric mapping between the original data and LSTM response. The results showed that IEMG+WL yields the best feature combination performance. The best performing variation was MG + RF + VM (rposition = 0.9099 and rmoment = 0.9707) whereas, PL (rposition = 0.9001, rmoment = 0.9703) and GMax+VM (rposition = 0.9010, rmoment = 0.9718) were distinguished as the economic and practical variations, respectively. The study established for the first time the use of nonnormalized sEMG in control algorithm development for level walking.

Gluteus maximus transfer for wound closure and treatment of abductor deficiency: a single-plastic surgeon series.

Due to the increasing number of total hip arthroplasties (THA), the number and complexity of revision procedures are also on the rise. For complex cases such as periprosthetic joint infections with soft tissue compromise or for abductor muscle deficiencies, one of the treatment options is a gluteus maximus flap (GMF) that covers dead space and can help restore the failed abductor mechanism. The purpose of this study is to investigate the outcomes of a single-plastic surgeon's series of GMF procedures. This retrospective review reports on 57 patients (mean follow-up 39.2months) undergoing GMF transfers for abductor insufficiency on native hip (N = 16), for abductor insufficiency in aseptic revision THA (rTHA) (N = 16), for soft tissue defects in aseptic rTHA (N = 8) and for soft tissue defects in septic rTHA (N = 17) by a single plastic surgeon over a 10-year period. Revision-free survival and complication rates were assessed and risk factors were analyzed with Cox-regression analysis. The reoperation-free survival rate of GMF for abductor insufficiency in native hips was 100%. GMF procedures for soft tissue defects in septic rTHA had the lowest cumulative revision-free survival (34.3%) and highest reinfection rates (53.9%). More than three prior surgeries (HR = 2.9, p = 0.020), presence of infection (HR = 3.2, p = 0.010) and resistant organisms (HR = 3.1, p = 0.022) significantly increased the risk of revision. GMF is a viable option for addressing abductor insufficiency in native hip joints. However, high revision and complication rates are reported for GMF in septic rTHA. This study highlights the need to clarify the circumstances for which the flap reconstruction will be indicated.

Women with low back pain do not show a pattern in the lumbopelvic muscle activation sequence that differentiates from women without low back pain

BackgroundOne of the causes of low back pain can be directly related to mechanical stability. Stability is the result of coordinated muscle patterns. One of the clinical tests used to assess the pattern of muscle activation is the hip extension test in the prone position, which is considered a reliable test to evaluate lumbopelvic stability. The aim of this study was to investigate whether there is a difference in the time of activation of these muscles between women with and without chronic low back pain. MethodIt is a cross-sectional study carried out with 28 women, 17 women without low back pain and 11 with pain complaints. The electromyographic signals from the spinal erector muscles, gluteus maximus and biceps femoris were collected during the performance of 3 repetitions of the tests. ResultsA total of 22 different sequences were found, 14 in the group without low back pain (NLBPG) and 16 in the group with low back pain (LBPG). Only 8 sequences were common in both groups. Muscle activation sequences were also compared between repetitions, the number of different sequences increased at each repetition and the accumulated percentage corresponding to the second most prevalent sequence decreased. ConclusionNo significant differences were found in onset values between groups. The results demonstrate that there is no pattern in the activation sequence of these muscles and we can understand that pelvic stabilization seems to depend on individual strategies.

Effects of Gluteus Maximus Muscle Activity and Pelvic Width on Dynamic Frontal Plane Hip Joint Stiffness During Gait in Healthy Young Women.

Excessive hip adduction and internal rotation are abnormal movements that may lead to the onset and progression of patellofemoral pain. Previous studies have reported that lower dynamic frontal plane hip joint stiffness in the gait of women is associated with the magnitude of hip adduction and internal rotation angles. However, the factors contributing to the lack of dynamic frontal plane hip joint stiffness in the gait of young women are unclear. This study aims to investigate the factors affecting dynamic frontal plane hip joint stiffness during the weight-acceptance phase of the gait of healthy young women. Cross-sectional study. This study included 30 healthy women between the ages of 18 and 30years. The pelvic width/femur length ratio was calculated by dividing the pelvic width by the femur length. Data on hip kinematics and kinetics and activation of the gluteus maximus and medius, tensor fasciae latae, and adductor longus muscles during gait were collected using a motion capture system, force plates, and surface electromyography. Stepwise multiple regression analysis was conducted to determine the extent to which each independent factor affected dynamic frontal plane hip joint stiffness. In healthy young women, decreased dynamic frontal plane hip joint stiffness was associated with decreased muscle activity of the gluteus maximus during the gait, as well as greater pelvic width/femur length ratio. Women with a relatively great pelvic width relative to femur length may have more difficulty in producing dynamic frontal plane hip joint stiffness. However, increasing the muscle activity of the gluteus maximus may contribute to increased dynamic frontal plane hip joint stiffness.

Three Episodes of Presumed Culture-Negative Septic Arthritis Following Intramuscular Antipsychotic Injections: A Case Report.

We present a male patient of low socioeconomic status and Māori ethnicity who experienced 3 episodes of presumed culture-negative septic arthritis of the native hip between ages 43 and 52 years. Each episode occurred within 3 weeks of intramuscular antipsychotic injection into the ipsilateral gluteal muscles. The right hip was involved in 2 presentations and the left hip in 1 presentation. No coexisting infection or underlying immune suppression was identified, and at follow-up 2 years after the last episode, he has no sequelae of septic arthritis. This report describes 3 episodes of presumed culture-negative septic arthritis after intramuscular antipsychotic injection.

Acute Effects of Dry Needling on Lower Limb Muscle Strength in CrossFit Athletes with Latent Trigger Points: A Randomized Triple-Blinded Pilot Clinical Trial

Study purpose. The purpose of this study was to evaluate the acute effect of deep dry needling (DP) on lower-limb muscle strength-related variables in CrossTraining recreational athletes with latent trigger point (TrP). Materials and methods. A total of 19 healthy CrossFit®-trained males (27.8 [4.7] years; 79.8 [10.4] kg; 1.76 [0.07] cm) with myofascial TrP in quadriceps, gluteus or gastrocnemius muscles completed this repeated-measures triple-blind pilot clinical trial. Participants were randomly allocated into either experimental (EG, n = 10) or Sham (SG, n = 9) groups. After allocation, the assessment of lower-limb muscle power (squat jump [SJ] and countermovement jump [CMJ]) and maximal isometric hip abduction and quadriceps strength were measured at baseline and after 48 hours of the intervention. Results. The results are expressed as Δ (SD) [95% CI]; unbiased Cohen’s d [dunb, 95% CI]). DN has been shown to reduce the presence of muscle TrP. The maximal isometric hip abduction strength had a moderate-to-high significant increase in the EG (left: 21.5 (16.9) [9.42, 33.57]; 0.55 [0.19, 0.99], right: 20.3 (16.2) [8.70, 31.89]; 0.74 [0.25, 1.35]); however, the Sham group only showed significant improvement in the left hip abductor muscles 15.77 (15.37) [3.96, 27.59]; 0.57 [0.11, 1.12]) with no significant changes in the right side. Conclusions. The acute reduction of myofascial TrP was observed with the application of DN but had no significant effect on maximal isometric strength or jump height compared to the Sham group. Results of this pilot clinical trial can be used to commission future research.

Breast Cancer Metastatic to Gluteus Maximus: A Case Report

Breast cancer rarely metastasizes to skeletal muscle. Moreover, skeletal muscle is a rare site of metastasis for any type of cancer. In this study, we report an unexpected finding of an enlarged mass in the gluteus maximus of an asymptomatic patient with a distant history of breast cancer. The mass was observed during computed tomography evaluation in preparation for a non-oncologic procedure. Biopsy and pathological investigation confirmed breast cancer metastasis. An increased awareness of rare metastatic sites is important so that such lesions are critically evaluated during early imaging examination.

Can gluteal muscle activation discriminate functional performance in moderately trained women? - A cross-sectional study

ABSTRACT This study verified whether the level of gluteal activation during a controlled maximum voluntary contraction may discriminate functional performance in women. Forty-five moderately trained women were assigned to two groups based on the level of gluteal muscle activation on maximum voluntary isometric contraction (MVIC) tests in the dominant limb: higher gluteal activation (HG—n = 22) and lower gluteal activation (LG—n = 22), considering different situations: a) level of activation of the gluteus medius muscle (GMed), b) level of activation of the gluteus maximus muscle (GMax), and c) level of combined activation of the GMed and GMax muscles. The cut-off values for the allocation of participants to groups in each situation were established as a function of the median values of each data set. Functional performance was assessed using the shuttle run, triple hop test, and six-metre timed hop test (STHT). The level of significance was set at 5%. Cohen’s d index was included to estimate the magnitude of existing differences. The HG showed significantly shorter times than the LG on STHT performance (p-values ranging from 0.03–0.04), with a moderate effect (Cohen’s d = 0.60–0.68) in all situations. The level of gluteal activation could discriminate STHT performance in women.