Quadriceps Muscle Group Research Articles

Leg Muscle Strength After Lateral Interbody Fusion Surgery Recovers Over Time After Temporary Muscle Weakness.

Case-control study. The objective of this study was to reveal the changes of leg muscle strength after lateral interbody fusion (LIF). Muscle trauma and damage to intermuscular nerves due to dissection of the psoas are recognized perioperative complications of LIF. Although reduced leg strength is temporary in many cases, the underlying changes have not been studied in detail. Leg muscle strength was measured quantitatively before LIF surgery and 1 week, 2 weeks, 3 weeks, 4 weeks, 8 weeks, and 12 weeks after surgery (n=38). Reduced muscle strength was defined as <80% of the preoperative measurement. The psoas position (PP%) was calculated from axial T2-weighted magnetic resonance images and compared with the degree of psoas and quadriceps muscle strength reduction at 1 week after surgery on the approach side. Twenty cases that underwent a posterior lumbar approach (posterior group) acted as controls. The proportion of patients with reduced psoas muscle strength 1 week after LIF was 60.5% on the approach side and 39.5% on the healthy side, versus 30.0% in the posterior group. The corresponding results for the quadriceps were 34.2%, 39.5%, and 25.0%, respectively. All cases had strength improvement on the approach side by 12 weeks postsurgery in the psoas and by 4 weeks postsurgery for the quadriceps. Psoas muscle strength and quadriceps strength at 1 week after surgery were correlated (ρ=0.57, P<0.001). There was a low inverse correlation between PP% and quadriceps strength at 1 week (ρ=-0.31, P<0.001). Muscle strength declined in both the psoas and quadriceps muscle groups after LIF; however, the effect was temporary and strength recovered over time. Reduced postoperative quadriceps muscle strength may relate the position of the psoas muscle via increased irritation of the lumbar plexus during the splitting maneuver.

Muscular Preconditioning Using Phototherapy Improves the Physical Work Capacity of the Quadriceps when Applied between Repeated Bouts of Resistance Exercise

Preconditioning skeletal muscle with phototherapy is an experimental technique for producing resistance against muscular fatigue during and after strenuous exercise. This study examined the ergogenic effects of phototherapy when applied intermittently during passive recovery between repeated bouts of isokinetic quadriceps exercise. A triple-blind, repeated measures, placebocontrolled, cross-over design was used in this study to compare the effects of phototherapy on torque/work and power output of the knee extensors in 20 healthy individuals (10 men, 10 women). The exercise protocol consisted of four repeated bouts of isokinetic exercise. Each bout consisted of 30 continuous knee extension concentric contractions at an angular velocity of 75°/s with a 4min recovery interval between bouts. Subjects received active and sham phototherapy in random order during passive recovery between exercise bouts. Phototherapy was administered using a near-infrared laser to the quadriceps femoris muscle group at 10 J/cm2 (total dose of 1600-2400 J). Performance measures included normalized peak torque [Nm/ kg], average peak torque [Nm], total work [Nm], and average power [W]. During the second, third and fourth exercise bouts, subjects produced significantly more torque (normalized and average) and total work/average power output during the active phototherapy condition compared to the sham phototherapy condition. Phototherapy applied as a preconditioning treatment during passive recovery intervals between bouts high of intensity and high volume resistance exercise significantly attenuated fatigue and maintained muscular performance of the quadriceps femoris muscle group. Preconditioning skeletal muscle with phototherapy intermittently during recovery intervals with fatiguing exercise may be a beneficial, non-invasive and safe ergogenic aid for athletes that require high levels of muscular endurance.

Muscle group excision is an effective and safe surgical treatment for soft tissue sarcoma of thigh

Objective To evaluate the local recurrence rate, limb function and complications of soft tissue sarcoma of thigh after muscle group resection. Methods Between January 2009 and August 2016, twenty-threepatients who were diagnosed as soft tissue sarcoma for the first time in our hospital, receiving thigh quadriceps muscle group resection, adductor muscle group resection or posterior compartment of the thigh resection were incorporated into this study. Patients who had received surgery of this lesion before, suffered from recurrent soft tissue tumor, had tumor involved multiple muscle groups which could not be resected completely, had sciatic nerve or femoral artery or vein affected by tumor or had distal metastasis were excluded. This retrospective study consisted of 12 male and 11 female. The age ranged from 20-80 with the average of 52. All the patients received CT and MRI of thigh to figure out the size of tumor, the invaded extension of the lesion and the specific muscle group involved. Chest CT scan and ultrasound of bilateral inguinal lymph nodes were arranged to exclude the tumor metastases. After all these examinations were done, needle biopsy with the guidance of CT scan was performed for the pathological diagnosis. The pathology included undifferentiated pleomorphic sarcoma (7 cases), rhabdomyosarcoma (2 cases), primitive neurotodermal tumor (1 case), synovial sarcoma (1 case), leiomyosarcoma (3 cases), fibrosarcoma (5 cases) and liposarcoma (4 cases). Sixpatients received quadriceps muscle group resection, eightpatients received adductor muscle group resection and the other 9 patients received posterior compartment of the thigh resection. Patients with undifferentiated pleomorphic sarcoma, leiomyosarcoma, primitive neurotodermal tumor and synovial sarcoma received postoperative adjuvant chemotherapy. None of patients received radiotherapy. After surgery, drainage tube of negative pressure was placed until the volume of drainage was less than 50 ml within 24 h. The affected thigh was bound up tightly. Intravenous antibiotics were used for 3 days to prevent from postoperative infections. Patients received quadriceps muscle group resection stayed in the bed for 4 weeks. After that they could walk with the protection of orthosis with unbending position. Other patients got out of bed after 2 weeks. All the complications after surgery were recorded. Reexaminations were arranged in 3, 6, 12 and 24 months after surgery separately. After that, reexamination was arranged every half a year. Chest CT scan was used to detect lung metastasis and ultrasound or MRI was arranged for local recurrence. Lower limb function after surgery was evaluated by MSTS scores. Results All the surgeries of muscle group excision were successfully completed. The duration of surgery ranged 1.5-3.5 h with the average of 2.2 h. The bleeding volume during surgery ranged 100-1 100 mL with the average of 313 mL. The follow-up was a mean of 41 months (range, 17-108 months). None was lost to follow-up. The local recurrence rate was 4.3% (1/23). One patient with undifferentiated pleomorphic sarcoma had positive surgical margin, who received posterior compartment of the thigh resection. Local recurrence occurred 6 months after surgery. Then he received expanded resection. Six patients had distant metastases, five patients for lung metastases, one patient for lung and inguinal lymph node metastases. Of these, five patients had died and one lived with the metastasis. The median MSTS score was 26.3 points (range, 14-30 points). Specifically, the median musculoskeletal tumor society (MSTS) score was 28 points (range, 21-30 points) for 9 patients with posterior compartment of the thigh resection, twenty-nine points (range, 27-30 points) for 8 patients with adductor muscle group resection, and 20.3 points (range, 14-24 points) for 6 patients with quadriceps muscle group resection. Five patients had complications, including local recurrence (1 case), hematoma (2 cases) and cutaneous necrosis (2 cases), all of which were settled by reoperation. The rate of complication was 21.7%. Conclusion Muscle group resection is an effective surgical treatment for soft tissue sarcoma of thigh, which could reduce the risk of local recurrence, apart from quadriceps muscle group resection, the other two muscle group resections have limited impact on lower limb function, additionally, thigh muscle group resection is a safe procedure with few complications. Key words: Sarcoma; Pathology, surgical; Neoplasm recurrence, local; Treatment outcome

Mechanomyography-based muscle fatigue detection during electrically elicited cycling in patients with spinal cord injury.

Patients with spinal cord injury (SCI) benefit from muscle training with functional electrical stimulation (FES). For safety reasons and to optimize training outcome, the fatigue state of the target muscle must be monitored. Detection of muscle fatigue from mel frequency cepstral coefficient (MFCC) feature of mechanomyographic (MMG) signal using support vector machine (SVM) classifier is a promising new approach. Five individuals with SCI performed FES cycling exercises for 30min. MMG signals were recorded on the quadriceps muscle group (rectus femoris (RF), vastus lateralis (VL), vastus medialis (VM)) and categorized into non-fatigued and fatigued muscle contractions for the first and last 10min of the cycling session. For each subject, a total of 1800 contraction-related MMG signals were used to train the SVM classifier and another 300 signals were used for testing. The average classification accuracy (4-fold) of non-fatigued and fatigued state was 90.7% using MFCC feature, 74.5% using root mean square (RMS), and 88.8% with combined MFCC and RMS features. Inter-subject prediction accuracy suggested training and testing data to be based on a particular subject or large collection of subjects to improve fatigue prediction capacity. Graphical abstract ᅟ.

Soft Actuating Sit-to-Stand Trainer Seat

In this paper, we propose a novel type of soft robot for sit to stand (STS) training, which is made with soft bellow actuators. Analysis with five healthy human subjects revealed that there is a statistically significant decrease in the peak and mean muscle activation signal from three out of the four groups of lower limb muscle for STS transition, namely, tibialis anterior, hamstrings, and quadriceps. The peak muscle activation decreased most drastically on the quadriceps muscle group (0.726 ± 0.467 to 0.269 ± 0.334). As reduced muscle activation signal correlates to less muscular effort required by the users, the results show the effectiveness of the device in partially supporting the STS transition of the subject, which subsequently serves as an STS trainer device.

Anisotropic elastic properties of the fascia lata during muscle contraction at different intensities - a shear wave elastography study

Introduction: Deep fascia wraps skeletal muscles and shows site-dependent differences in morphological and mechanical properties (Findley et al 2015). The quadriceps femoris muscle group is one of the largest in the human body (Lieber 1992) and exerts strong forces when it contracts. Thus, a great magnitude of mechanical load would be imposed on the fascia lata during contraction. However, the behavior of the fascia lata during muscle contraction remains undetermined. The purpose of this study was to investigate the dependence of the fascia lata elasticity on contraction intensity during knee extension.

Damaged muscle fibers might masquerade as hybrid fibers - a cautionary note on immunophenotyping mouse muscle with mouse monoclonal antibodies.

We report that, labeling mouse muscle tissue, with mouse monoclonal antibodies specific to slow or fast myosin heavy chain (sMyHC and fMyHC, respectively), can lead to artefactual labeling of damaged muscle fibers, as hybrid fibers (sMyHC+ and fMyHC+). We demonstrate that, such erroneous immunophenotyping of muscle may be avoided, by performing colabeling or serialsection- labeling, to identify damaged fibers. The quadriceps femorismuscle group (QF) in 7-month-old, male, C57BL/6J mice had: 1.21±0.21%, 98.34±1.06%, 0.07±0.01%, and 0.53±0.85% fibers, that were, sMyHC+, fMyHC+, hybrid, and damaged, respectively. All fibers in the tibialis anterior muscle (TA) of 3-month-old, male, C57BL/6J mice were fMyHC+; and at 3 days after injurious eccentric contractions, there was no fiber-type shift, but ~ 18% fibers were damaged.

Exercise Programmes for Osteoarthritis with Different Localization.

Therapeutic exercises in osteoarthritis (OA) are therapeutic approach with proven efficacy. However, the different disease forms, the lack of established consensus and system for patient education limit the widespread use of therapeutic exercises in clinical practice. The mechanisms of action of therapeutic exercise in OA include the following components e.g. neuromuscular (improvement of proprioception, muscle strength and joint stability), intra-articular (prevention of cartilage degeneration, antiinflammatory effect, improvement of the quality of the joint fluid), periarticular, general health with reduction of cardiovascular risk and psychological components. The main exercises, which are used in OA patients, are stretching exercises, range of motion exercises, analytic exercises for muscle strengthening (isometric and isotonic) and aerobic exercises (walking, cycling, swimming, etc.). The recommended exercise programmes have to be individualized according to patient age, severity of OA and presence of concomitant diseases. The analytic exercises for improvement of muscle strength in hip OA aim to influence the abductors, adductors, flexors and extensors of the hip joint. In knee OA, the target muscle groups are thigh muscles (quadriceps muscle and posterior group of thigh muscles), calf muscles (triceps surae muscle) as well as muscles around the hip joint. There are no established programmes for therapeutic exercises regarding the intensity, frequency, the degree and the interval for increasing of joint load. No significant difference in the efficacy of group vs. individual exercise programmes has been observed. In OARSI recommendations (2010), it is underlined that aerobic exercises and those for muscle strength have a moderate efficacy in knee OA for pain relief e.g. ES (effect size) - 0.52 (for aerobic exercises) and 0.32 (for strengthening exercises). The ES for functional improvement is 0.46 for the aerobic exercises and 0.32 for the strengthening exercises. The data for the role of therapeutic exercises in hip OA are scarce. An effect on pain has been observed (ES-0.38) but without improvement of functional capacity. Therapeutic exercises have low to moderate complex efficacy in patients with OA. They should be an obligatory part in the therapeutic regimens of the patients, which requires close collaboration between rheumatologists, general practitioners and physiotherapists as well as establishment of system for patient education.

Immediate effect of Kinesio Tape on maximal muscle strength in vertical jump performance on healthy martial artists

Objective: to analyze the immediate effect of kinesio tape (KT) in vertical jump performance, applied from insertion to origin on the quadriceps muscle group.&#x0D; Methods: 14 martial artists (11 males and 3 females), All the participants jumped without KT and then jumped with KT, in both situations, they jumped three times and the best jump was saved for analysis. The selected jump test was Squat Jump, following the BOSCO Protocol, using the Axon Jump© platform model S.&#x0D; Results: The variables were time of flight (TF), height (H) and speed (S), they were measured by the Axon Jump© platform and the data was analyzed using SPSS 19© software. The best jump for all situations was analyzed on a T test, showing that all, but three subjects, had a decrease jump performance using KT.&#x0D; Conclusion: our results suggest that the application of KT can have an immediate effect on vertical jump performance, in this case a decrease effect when it’s applied from insertion to origin of the muscles.

Immediate effect of Kinesio Tape on maximal muscle strength in vertical jump performance on healthy martial artists

Objective: to analyze the immediate effect of kinesio tape (KT) in vertical jump performance, applied from insertion to origin on the quadriceps muscle group.&#x0D; Methods: 14 martial artists (11 males and 3 females), All the participants jumped without KT and then jumped with KT, in both situations, they jumped three times and the best jump was saved for analysis. The selected jump test was Squat Jump, following the BOSCO Protocol, using the Axon Jump© platform model S.&#x0D; Results: The variables were time of flight (TF), height (H) and speed (S), they were measured by the Axon Jump© platform and the data was analyzed using SPSS 19© software. The best jump for all situations was analyzed on a T test, showing that all, but three subjects, had a decrease jump performance using KT.&#x0D; Conclusion: our results suggest that the application of KT can have an immediate effect on vertical jump performance, in this case a decrease effect when it’s applied from insertion to origin of the muscles.

Duration Dependent Effect of Static Stretching on Quadriceps and Hamstring Muscle Force.

The aim of this study was to determine the acute effect of static stretching on hamstring and quadriceps muscles’ isokinetic strength when applied for various durations to elite athletes, to investigate the effect of different static stretching durations on isokinetic strength, and finally to determine the optimal stretching duration. Fifteen elite male athletes from two different sport branches (10 football and five basketball) participated in this study. Experimental protocol was designed as 17 repetitive static stretching exercises for hamstring and quadriceps muscle groups according to the indicated experimental protocols; ((A) 5 min jogging; (B) 5 min jogging followed by 15 s static stretching; (C) 5 min jogging followed by 30 s static stretching; (D) 5 min jogging, followed by static stretching for 45 s). Immediately after each protocol, an isokinetic strength test consisting of five repetitions at 60°/s speed and 20 repetitions at 180°/s speed was recorded for the right leg by the Isomed 2000 device. Friedman variance analysis test was employed for data analysis. According to the analyzes, it was observed that 5 min jogging and 15 s stretching exercises increased the isokinetic strength, whereas 30 and 45 s stretching exercises caused a decrease.

Predicting 1 Repetition Maximum Using Handheld Dynamometry

BackgroundIsometric assessment of muscular function using a handheld dynamometer (HHD) is frequently used in clinic environments. However, there is controversy in terms of the validity of isometric assessment to monitor changes in dynamic performance. One repetition maximum (1RM) is considered the gold standard for evaluating dynamic strength, though clinicians do not often use 1RM testing, preferring to be cautious with clients who have preexisting impairments. If strength testing using an HHD could be used to predict 1RM, this may have significant implications for the use of isometric testing to prescribe exercise in clinical environments. ObjectiveTo establish the relationship and agreement between 1RM and isometric strength scores measured using HHD for the biceps and quadriceps muscle groups and to determine if HHD measurements can be used to predict 1RM. DesignCriterion standard comparison. SettingTertiary institution gymnasium. ParticipantsConvenience sample of 50 healthy adults (26 women) aged 19-33 years (mean 23.38 ± 3.11 years). MethodsMuscle strength of the biceps and quadriceps muscle groups measured by 1RM and isometric maximal voluntary contraction measured using an HHD. Main Outcome MeasuresStatistical analysis of the relation between the measures of strength was established using Pearson correlation and a Bland-Altman plot. A linear regression analysis with included covariates (gender, age, resistance training history, and body mass index) was used to derive the prediction equations. ResultsA significant correlation was found between 1RM and HHD scores for the biceps (r = .83, P < .001) and quadriceps muscle groups (r = .82, P < .001). However, strength scores were not in agreement. Linear regression analysis found significance in predicting 1RM from all HHD scores (P < .001). Gender as a covariate significantly influenced the prediction of 1RM for the biceps (P = .005) and quadriceps (P = .003) muscle groups. ConclusionsThere is a significant relationship between 1RM and HHD measures of strength, and measures taken using an HHD can be used to predict 1RM in the biceps and quadriceps muscle groups. The use of an HHD may therefore provide a more accessible alternative to 1RM for muscle strength assessments. Further research is warranted to determine if results are applicable in clinical populations. Level of EvidenceNA

The Anatomy of the Articularis Genus Muscle and Its Relation to the Extensor Apparatus of the Knee.

Background:The anatomy of the articularis genus muscle has prompted speculation that it elevates the suprapatellar bursa during extension of the knee joint. However, its architectural parameters indicate that this muscle is not capable of generating enough force to fulfill this function. The purpose of the present study was to investigate the anatomy of the articularis genus, with special emphasis on its relationship with the adjacent vastus intermedius and vastus medialis muscles.Methods:The articularis genus muscle was investigated in 18 human cadaveric lower limbs with use of macrodissection techniques. All components of the quadriceps muscle group were traced from origin to insertion, and their affiliations were determined. Six limbs were cut transversely in the middle third of the thigh. The modes of origin and insertion of the articularis genus, its nerve supply, and its connections with the vastus intermedius and vastus medialis were studied.Results:The muscle bundles of the articularis genus were organized into 3 main layers: superficial, intermediate, and deep. The bundles of the superficial layer and, in 60% of the specimens, the bundles of the intermediate layer originated from both the vastus intermedius and the anterior and anterolateral surfaces of the femur. The bundles of the deep layer and, in 40% of the specimens, the bundles of the intermediate layer arose solely from the anterior surface of the femur. The distal insertion sites included different levels of the suprapatellar bursa and the joint capsule. A number of connections between the articularis genus and the vastus intermedius were found. While the vastus medialis inserted into the whole length of the vastus intermedius aponeurosis, it included muscle fibers of the articularis genus, building an intricate muscle system supplied by nerve branches of the same medial deep division of the femoral nerve.Conclusions:The articularis genus, vastus medialis, and vastus intermedius have a complex, interacting architecture, suggesting that the articularis genus most likely does not act as an independent muscle. With support of the vastus intermedius and vastus medialis, the articularis genus might be able to function as a retractor of the suprapatellar bursa. The finding of likely interplay between the articularis genus, vastus intermedius, and vastus medialis is supported by their concurrent innervation.Clinical Relevance:The association between the articularis genus, vastus medialis, and vastus intermedius may be more complex than previously believed, and this close anatomical connection could have functional implications for knee surgery. Dysfunction, scarring, or postoperative arthrofibrosis of the sophisticated interactive mechanism needs further investigation.

Radiographic measurement of the quadriceps angle in dogs.

The direction of the force of the quadriceps muscle group is expressed by the value of the quadriceps angle, between the long axis of the muscle rectus femoris and the patellar ligament. This value is often modified in dogs with patellar luxation, a common orthopaedic disease of the stifle joint in both small and large dogs. The aims of the present study were to give a reference value for the quadriceps angle in healthy small and medium-large breed dogs. The medical records of healthy dogs and their pelvic limb radiographs (2014–2016) were reviewed. The radiographs were then divided into two groups: Group A (small dogs <15 kg body weight) and Group B (medium-large dogs >15 kg). The quadriceps angle of each pelvic limb was assessed using a digital software program in order to compare values between the two groups. The radiographs of 160 dogs, 80 per group were studied along with the assessment of the 320 pelvic limbs. The median quadriceps angle values obtained were in contrast with the literature: in Group A, it was 18.3° and, in Group B, it was 8.7°; moreover, the quadriceps angle value for Group A was statistically higher than for Group B (p<0.0001). No significant difference was present between males and females, or between right and left hindlimbs. In Group B, the Labrador Retriever breed influenced the quadriceps angle (p = 0.0005). The outcome of this survey provides an objective parameter, or additional information, to explain the different quadriceps mechanisms of small and medium-large dogs. In future studies the QA range values assessed in the two size groups may be useful in defining the magnitude of the malalignment of the extensor mechanism in both healthy dogs and ones with patellar luxation.

Evaluation of Isokinetic Single-Leg Cycling as a Rehabilitation Exercise Following Anterior Cruciate Ligament Reconstruction Surgery

The anterior cruciate ligament (ACL) is one of the most commonly injured ligaments, with over 250,000 injuries per year in the United States. Previous studies have found that ACL-deficient individuals avoid use of the quadriceps in the injured limb as a means of limiting anterior movement of the tibia in the absence of a functioning ACL. From these results, a study was designed to investigate the effectiveness of isokinetic single-leg cycling in increasing quadriceps muscle recruitment and activation. Ten control and seven ACL-reconstructed subjects completed a series of 15 s cycling trials in isokinetic mode at 75 rpm, while kinematic, kinetic, and electromyographic data of the lower limbs were collected, with the trials including both double-leg and single-leg cycling. It was hypothesized that there would be an increase in quadriceps muscle activity, peak knee extensor moment, and knee joint power in single-leg cycling when compared to double-leg cycling. The results of the study suggest that single-leg cycling may be an effective exercise in increasing the strength of the quadriceps following anterior cruciate ligament reconstruction surgery. Although no significant changes occurred, the results indicate that, given a specific limb power, more muscle force will be generated from the quadriceps muscle group in single-leg cycling than double-leg cycling.

Exposure to microgravity for 30 days onboard Bion M1 caused muscle atrophy and impaired regeneration in murine femoral Quadriceps

Mechanical unloading in microgravity during spaceflight is known to cause muscular atrophy, changes in muscle fiber composition, gene expression, and reduction in regenerative muscle growth. Although some limited data exists for long-term effects of microgravity in human muscle, these processes have mostly been studied in rodents for short periods of time. Here we report on how long-term (30-day long) mechanical unloading in microgravity affects murine muscles of the femoral Quadriceps group. To conduct these studies we used muscle tissue from 6 microgravity mice, in comparison to habitat (7), and vivarium (14) ground control mice from the NASA Biospecimen Sharing Program conducted in collaboration with the Institute for Biomedical Problems of the Russian Academy of Sciences, during the Russian Bion M1 biosatellite mission in 2013. Muscle histomorphology from microgravity specimens showed signs of extensive atrophy and regenerative hypoplasia relative to ground controls. Specifically, we observed a two-fold decrease in the number of myonuclei, compared to vivarium and ground controls, and central location of myonuclei, low density of myofibers in the tissue, and of myofibrils within a fiber, as well as fragmentation and swelling of myofibers. Despite obvious atrophy, muscle regeneration nevertheless appeared to have continued after 30 days in microgravity as evidenced by thin and short newly formed myofibers. Many of them, however, showed evidence of apoptotic cells and myofibril degradation, suggesting that long-term unloading in microgravity may affect late stages of myofiber differentiation. Ground asynchronous and vivarium control animals demonstrated normal, well-developed tissue structure with sufficient blood and nerve supply and evidence of regenerative formation of new myofibers free of apoptotic nuclei. Regenerative activity of satellite cells in muscles was observed both in microgravity and ground control groups, using Pax7 and Myogenin immunolocalization, as well as Myogenin expression analysis. In addition, we have detected positive nuclear immunolocalization of c-Jun and c-Myc proteins indicating their sensitivity to changes in gravitational loading in a given model. In summary, long-term spaceflight in microgravity caused significant atrophy and degeneration of the femoral Quadriceps muscle group, and it may interfere with muscle regenerative processes by inducing apoptosis in newly-formed myofibrils during their differentiation phase.

Development of a bedside viable ultrasound protocol to quantify appendicular lean tissue mass.

BackgroundUltrasound is a non‐invasive and readily available tool that can be prospectively applied at the bedside to assess muscle mass in clinical settings. The four‐site protocol, which images two anatomical sites on each quadriceps, may be a viable bedside method, but its ability to predict musculature has not been compared against whole‐body reference methods. Our primary objectives were to (i) compare the four‐site protocol's ability to predict appendicular lean tissue mass from dual‐energy X‐ray absorptiometry; (ii) optimize the predictability of the four‐site protocol with additional anatomical muscle thicknesses and easily obtained covariates; and (iii) assess the ability of the optimized protocol to identify individuals with low lean tissue mass.MethodsThis observational cross‐sectional study recruited 96 university and community dwelling adults. Participants underwent ultrasound scans for assessment of muscle thickness and whole‐body dual‐energy X‐ray absorptiometry scans for assessment of appendicular lean tissue. Ultrasound protocols included (i) the nine‐site protocol, which images nine anterior and posterior muscle groups in supine and prone positions, and (ii) the four‐site protocol, which images two anterior sites on each quadriceps muscle group in a supine position.ResultsThe four‐site protocol was strongly associated (R 2 = 0.72) with appendicular lean tissue mass, but Bland–Altman analysis displayed wide limits of agreement (−5.67, 5.67 kg). Incorporating the anterior upper arm muscle thickness, and covariates age and sex, alongside the four‐site protocol, improved the association (R 2 = 0.91) with appendicular lean tissue and displayed narrower limits of agreement (−3.18, 3.18 kg). The optimized protocol demonstrated a strong ability to identify low lean tissue mass (area under the curve = 0.89).ConclusionsThe four‐site protocol can be improved with the addition of the anterior upper arm muscle thickness, sex, and age when predicting appendicular lean tissue mass. This optimized protocol can accurately identify low lean tissue mass, while still being easily applied at the bedside.

Differences in pressure pain threshold among men and women after foam rolling

BackgroundRehabilitation professionals often prescribe foam rolling as an intervention to augment other manual therapies or as a warm-up or recovery after athletic activity. Currently, there is a gap in the literature regarding how foam rolling effects the pressure pain threshold (PPT) among men and women. PurposeThe purpose of this study was to examine the immediate effects of a foam rolling intervention on the ipsilateral agonist, antagonist, and contralateral muscle group PPT among men and women. SettingUniversity kinesiology laboratory. ParticipantsTwenty healthy adults (M = 10, F = 10; mean age = 27.4 ± 8.5 years). Research designPre-test, post-test observational study. InterventionVideo-guided foam roll intervention on the left quadriceps group. Main outcome measuresIpsilateral quadriceps, ipsilateral hamstring, and contralateral quadriceps muscle PPT. ResultsWithin group comparison for men, revealed a statistically significant effect of time on PPT for the left quadriceps (p=<0.001), left hamstring (p = 0.001), and right quadriceps (p=<0.001). For women, there was a statistically significant effect of time on PPT for the left quadriceps (p = 0.001), left hamstring (p = 0.007), and right quadriceps (p=<0.001). No significant difference in PPT between men and women were found for the left quadriceps (p = 0.31), left hamstring (p = 0.13), and right quadriceps (p = 0.070) muscle groups. ConclusionsThese finding suggest that foam rolling can immediately reduce PPT in the ipsilateral agonist, antagonist, and contralateral muscle groups among men and women. Future investigations are needed to determine the long-term effects of foam rolling on PPT among sexes.

Anatomical Investigation of the Tensor Vastus Intermedius in the Quadriceps Muscle Group

Study ObjectivesThe aim of this study is to further investigate the presence of the tensor vastus intermedius (TVI) in a larger sample size of 80 thighs and also attempt to bring novel imaging techniques to the discussion.BackgroundUntil this year, the quadriceps muscle group has been described as containing four muscles, with few studies describing its deviation from this definition. Most recently, a study reported finding this additional muscle belly in all 26 cadaver dissections performed, which was then named TVI for its similarities to the tensor fascia lata (TFL) and its anatomical relationship to the vastus intermedius (VI) (Grob et al 2016).MethodsIn the preliminary dissections performed on 49 donor thighs we focused specifically on TVI presence, tendinous properties and nerve innervation. This current study includes 80 donor thighs and will include the previously stated focuses as well as the vascular supply of the TVI. Biostatistical analysis will also be used to find any correlation of TVI bilaterally or with known factors of the donor such as gender.ResultsAlong with the TVI muscle belly presence, there is variation among its tendinous contribution to the quadriceps tendon, which is classified based on the muscle it fuses with, vastus lateralus (VL), VI or both, or whether it is completely independent.ConclusionOur preliminary investigation showed TVI presence in 38% of cadaver thighs, which is also what we expect to find in the additional 80 thighs analyzed of the present study.

Does Roller Massage With a Foam Roll Change Pressure Pain Threshold of the Ipsilateral Lower Extremity Antagonist and Contralateral Muscle Groups? An Exploratory Study.

Foam rolling is a popular intervention used by allied health professionals and the general population. Current research suggests that foam rolling may have an effect on the ipsilateral antagonist muscle group and produce a cross-over effect in the muscles of the contralateral limb. The purpose of this study was to examine the acute effects of foam rolling to the left quadriceps on ipsilateral antagonist hamstrings and contralateral quadriceps muscle group pressure pain threshold (PPT). Through this research, we sought to gather data to further develop the methodology for future studies of this intervention. A pretest-posttest exploratory study. University kinesiology laboratory. 21 healthy adults (age = 27.52 ± 8.9y). Video-guided foam roll intervention on the left quadriceps musculature. Ipsilateral hamstring (antagonist) and contralateral quadriceps muscle PPT. A significant difference was found between pretest to posttest measures for the ipsilateral hamstrings (t[20] = -6.2, P < 0.001) and contralateral quadriceps (t[20] = -9.1, P < 0.001) suggesting an increase in PPT. These findings suggest that foam rolling of the quadriceps musculature may have an acute effect on the PPT of the ipsilateral hamstrings and contralateral quadriceps muscles. Clinicians should consider these results to be exploratory and future investigations examining this intervention on PPT is warranted.