Lower Limb Muscle Groups Research Articles

Wearable Surface Deformation Myography (sDMG) System for Recognition of Locomotion Modes.

This study designs a wearable sensing system for locomotion mode recognition using lower-limb skin surface curvature deformation caused by the morphological changes of musculotendinous complexes and soft tissues. Flexible bending sensors are embedded into stretch pants, enabling curvature deformations of specific skin segments above lower-limb muscle groups to be captured in a noncontact manner. To evaluate the performance of this system, we conducted experiments on eight able-bodied subjects completing seven common locomotive activities, including walking, running, ramp ascending/descending, stair ascending/descending, and standing. The system measured seven channels of deformation signals from two cross-sections on the shank and the thigh. The collected signals were distinguishable across different locomotion modes and exhibited consistency when monitoring steps. Using selected time-domain features and a linear discriminant analysis (LDA) classifier enabled the proposed system to continuously recognize locomotion modes with an average accuracy of 96.5%. Furthermore, the system maintains recognition performance with 95.7% accuracy even after removing and reapplying the sensors. Finally, we conducted comparison experiments to analyze how window length, feature selection, and the number of channels affect recognition performance, providing insights for optimization. We believe that this novel signal platform holds great potential as a valuable supplementary tool in wearable human motion detection, enriching the information diversity for motion analysis, and enabling new possibilities for further advancements and applications in fields including biomedical engineering, textiles, and computer graphics.

Investigating the association between intralimb strength ratio, interlimb strength and range of motion asymmetry index, and functional limitations with fall incidence among older adults: protocol for a prospective cohort study

The present study aims to identify the intralimb strength ratio, interlimb strength and range of motion asymmetry index in elderly individuals and then investigate the association between these asymmetry indices...

Isometric muscle torque in Chilean children and adolescents evaluated by manual maintenance dynamometry: a reliability study

to determine the reliability of hand-held dynamometry to obtain the maximal isometric torque of upper and lower limb muscle groups in Chilean children and adolescents. Crosssectional study. Seventy-two participants aged between 7 and 15 years were selected from a school in Talca. Maximal isometric torque was recorded in 15 muscle groups of upper and lower limbs through hand-held dynamometry. Intra- and inter-rater evaluation was used, applying the intraclass correlation coefficient (ICC) to determine the reliability of the tests and Bland-Altman plots to evaluate concordance. The results demonstrated good to excellent inter-rater reliability (ICC = 0.850.98) and intra-rater reliability (ICC = 0.87-0.98). Only two groups, hip extensors and abductors, showed good inter-rater reliability (ICC = 0.85 and ICC = 0.88, respectively); and one group, the ankle dorsiflexors, showed good intra-rater reliability (ICC = 0.87). 100% of the tests presented at least 95.8% inter- and intra-rater agreement on the Bland-Altman plots. The evaluation of isometric muscle torque using hand-held dynamometry is a reliable procedure for use in different growth periods.

Case Report : Physiotherapy management of maternal obstetric palsy in a Nigerian teaching hospital

Introduction Maternal obstetric palsy is a rare nerve injury to all or part of the lumbosacral plexus with signs and symptoms becoming evident during labour or after childbirth. Motor and sensory involvement affect dermatomes and lower limb muscle group(s). Physiotherapy is indicated for the clinical presentations of maternal obstetric palsy, but research in this area is limited. The purpose of this case report was to highlight the application of physiotherapy in the management of the clinical presentations of maternal obstetric palsy. Clinical description A 38-year-old female patient presented with severe pain (verbal pain rating scale [VPRS]: 10/10), intermittent muscle spasm, loss of sensation, weakness of lower limb muscle groups (Oxford Muscle Grading [OMG]: ≤2/5) and loss of lower limb function after childbirth following prolonged obstructed labour. The patient was diagnosed with maternal obstetric palsy after detailed history and physical examinations. Interventions and outcomes Transcutaneous electrical muscle stimulation and muscle strengthening exercises were administered immediately post-delivery. Duration of treatment was eight weeks. The patient’s pain stopped (VPRS= 0/10), muscle spasm reduced, with improved muscle strength (OMG≥ 4/5) and lower limb function. Conclusion Early physiotherapy reduced pain intensity and muscle spasm, and increased muscle strength and function in a patient with maternal obstetric palsy.

An alternative EMG normalization method: Heterogeneous recurrence quantification analysis of isometric maximum voluntary contraction movements

This study presents an alternative method of normalizing Surface Electromyography (EMG) signals, which provide valuable insights into the musculoskeletal properties of the human body. Traditional normalization through the peak maximum voluntary contraction (MVC) method may result in variable outcomes due to its dependence on pre-processing steps such as smoothing and window length. To address this issue, the study standardizes the EMG pre-processing steps by using non-linear techniques, namely recurrence quantification analysis (RQA) and heterogeneous RQA (HRQA). RQA, specifically HRQA, functions as EMG feature extractors to explore the nonlinear dynamical system and state space trajectories of chaotic EMG signals. Principal component analysis (PCA) and kernel PCA (KPCA) were further applied to the RQA and HRQA results to obtain data with more information. The results show that the first principal components (PC1 and KPC1) of HRQA have a very strong relationship with peak MVC (ρ > |0.90|, p < 0.001), indicating their potential compared to the traditional EMG normalization technique for lower limb muscle groups. Additionally, the study investigated the dynamic differences among isometric MVC movements in lower limb muscle groups and found that the RQA and HRQA methods indicated a greater separation for detecting these differences compared to peak MVC. This study offers a valuable method for assessing the musculoskeletal characteristics of individuals who may have difficulty with activities like walking or providing maximum force during EMG data collection, such as those suffering from Parkinson's disease or walking disabilities. This enhances our understanding of their musculoskeletal properties.

Characteristics of Skeletal Muscle Strength in Subjects With Interstitial Lung Disease

ObjectivesTo investigate muscle strength and the prevalence of muscle weakness in adults with interstitial lung diseases (ILDs) compared to healthy subjects. DesignCross-sectional (description of clinical features). SettingPublic referral center (University Hospital). ParticipantsOne hundred and twelve adults with ILD (n=48, 60±10yr, 68% female) and healthy counterparts (control group, n=64, 57±10yr, 58% female) (N=112). InterventionNot applicable. Main Outcome Measure(s)Muscle strength and prevalence of muscle weakness in adults with ILD. Muscle strength was assessed via maximal isometric voluntary contraction of dominant upper and lower limb muscle groups. Data from the control group were used to generate reference equations. Muscle weakness was defined as a muscle strength value below the lower limit of normal calculated using data from the control group. Data were expressed as mean ± SD or median [interquartile range] according to the data distribution. ResultsCompared to the control group, adults with ILD had lower muscle strength for all muscle groups assessed (values presented as %predicted: pectoralis major 75[57-86]%; quadriceps 72[58-87]%; latissimus dorsi 76[57-103]%; deltoid 74[64-98]%; biceps brachii 78[64-91]%; triceps brachii 84[62-101]%; P≤.001 for all). Prevalence of muscle weakness in people with ILD was 40% for pectoralis major, 25% for latissimus dorsi, 16% for triceps brachii, 20% for biceps brachii, 27% for deltoid and 46% for quadriceps. ConclusionsAdults with ILD present a generalised reduction in peripheral Muscle strength, ranging between 20% to 46% of people depending on the muscle group assessed. and it was more prevalent in lower limb muscles.

The correlation between pregnancy-related low back pain and physical fitness evaluated by an index system of maternal physical fitness test.

To investigate incidence of pregnancy-related low back pain (LBP), evaluate physical fitness objectively during pregnancy and analyze the correlation between LBP and physical fitness of pregnant women, 180 pregnant women including 101 in mid-gestation (14-28 gestational weeks) and 79 in late-gestation (28-37 gestational weeks) were recruited and self-reported their LBP. The aerobic ability such as cardiorespiratory fitness and anaerobic ability including strength, endurance, speed, flexibility, and balance were evaluated by a novel materal physical fitness test system. The correlation between LBP and each component in physical fitness test system was analyzed in SPSS. As the results, 135 out of 180 participants (75% of total) had pregnancy-related LBP. Physical fitness of participants in late-gestation was significantly weaker including weaker back strength (p<0.05), less resistance band pullbacks in 30s (p<0.01), less stretching in sit-and-reach test (p<0.001), shorter duration in left legged blind balance test (p<0.05) and weaker bird dog balance(p<0.05) than those in mid-gestation. Correlation analysis indicated that LBP was negatively associated with standing heel raises in 20s (p<0.01) and standing glute kickbacks in 30s (left p<0.01, right p<0.05). Thus, it is concluded that LBP is in high prevalence throughout the entire pregnant course. The pregnant women are prone to have weakened strength of core muscle groups and poorer flexibility and balance along the pregnancy. In addition, their LBP was negatively correlated to strength of back muscle groups of lower limbs.

Establishment of regression-based normative isometric strength values for major lower limb muscle groups in persons with multiple sclerosis

Limb weakness is a major impairment that affects mobility in persons with multiple sclerosis (PwMS). Specifically, lower limb (LL) weakness can greatly affect gait and balance, while increasing fall risk and decreasing quality of life. Numerous studies have compared LL strength of PwMS to healthy controls, however none have objectively measured strength in all major LL joints (hip, knee, and ankle) in a large number of PwMS. Additionally, while discrete normative values exist for knee extensors in PwMS, there has yet to be regression-based normative isometric strength values for all major LL muscle groups. Therefore, this study aimed to develop gender-specific regression-based normative prediction equations, with 95% confidence intervals, for maximal isometric peak torque of major LL muscles in PwMS. A secondary aim was to characterize the prevalence of LL weakness in PwMS, defined as ≥ 2 SD below values reported for healthy individuals. A convenience sample of 175 (women: n=135) PwMS participated in a prospective, cross-sectional study where isometric peak torque of hip flexors, extensors, and abductors, knee flexors and extensors, and ankle plantarflexors and dorsiflexors were measured using the Biodex System 4 Pro-Dynamometer®. Demographics (age, height, and weight) and disease characteristics (disease duration and disability) were collected. Performances were separated for each muscle group into strongest limb and weakest limb. For each gender, regression-based equations were generated for the LL muscle groups by limb with age, height, weight, disability, and disease duration as the covariates. Descriptive statistics were used to examine the frequency of LL weakness by gender and disability level. For comparison purposes, age-stratified (<30, 30-39, 40-49, 50-59, 60-69, >70 years) and disability-stratified (mild, moderate, and severe ambulant) discrete peak torque values were also generated for each gender. Regression-based normative data are presented for men and women, accounting for age, height, weight, disability, and disease duration. Men were significantly stronger (P < 0.001) than women for all LL, with the men's models accounting for a greater percent of muscle strength variation than women's models for all muscle groups, except for hip extension. Disability was inversely related to strength in all of the models. LL weakness was prevalent in hip flexion (m: 47.5%; w: 63.0%) and extension (m: 92.5%; w: 88.1%), knee extension (m: 30.0%; w: 33.3%) and flexion (m: 25.0%; w: 34.8%), and ankle plantarflexion (m: 15.0%; w: 10.4%) and dorsiflexion (m: 100.0%; w: 96.3%). PwMS with mild disability had a high prevalence of ankle dorsiflexion (94.9-100.0%) and hip extension (81.4-90.0%) weakness. This study is the first to provide regression-based normative data of bilateral strength in all major LL muscle groups and clinically useful prevalence data on the occurrence of weakness in these muscles. Of note, PwMS had a high prevalence of ankle dorsiflexion and hip extension weakness even when they were only mildly disabled. These findings can help guide the direction of future interventions and treatments to improve muscle function in PwMS.

Impaired lower limb muscle mass, quality and function in end stage liver disease: A cross-sectional study.

What is the central question of this study? To what extent does musculoskeletal impairment occur (i.e., muscle mass, quality and function) in patients with end stage liver disease (ESLD) by comparison to a healthy age/sex-matched control group? What is the main finding and its importance? Muscle mass, quality and function are impaired in patients with ESLD (compared to age/sex matched controls). Importantly, greater impairments were seen in lower limb compared to arm and trunk muscle groups. These findings may suggest that there should be greater consideration of muscle health in functionally relevant lower limb muscle groups. Sarcopenia is associated with reduced quality of life and increased mortality in patients with end stage liver disease (ESLD). Historically, sarcopenia identification in ESLD utilised L3 skeletal muscle index (SMI). There are few data on muscle quality and function within lower limb muscle groups with high functional relevance. The aim of this prospective case-control study was to evaluate the quadriceps muscle in patients with ESLD. Muscle mass and quality were evaluated using MRI (quadriceps anatomical cross sectional area (ACSA), quadriceps volume index, L3 SMI, quadriceps intermuscular adipose tissue (IMAT)), mid-arm muscle circumference (MAMC) and ultrasonography (vastus lateralis (VL) thickness and quadriceps ACSA). Muscle strength/function was assessed by handgrip strength, peak quadriceps isokinetic torque and chair rise time. Thirty-nine patients with ESLD (55 years, 61% male, 48% alcoholic related liver disease (ArLD), 71% Child-Pugh B/C) and 18 age/sex-matched healthy control participants (HC) were studied. Quadriceps mass was significantly reduced in ESLD versus HC (-17%), but L3 SMI and MAMC were unchanged. Quadriceps IMAT percentage was increased in ESLD (+103%). Handgrip strength (-15%), peak isokinetic torque (-29%), and chair rise time (+56%) were impaired in ESLD. Ultrasound measures of VL thickness (r=0.56, r=0.57, r=0.42) and quadriceps ACSA (r=0.98, r=0.86, r=0.67) correlated to MRI quadriceps ACSA, quadriceps volume and L3 SMI, respectively. Quadriceps muscle mass, quality, and function were impaired in patients with ESLD, whereas conventional assessments of muscle (L3 SMI and MAMC) highlighted no differences between ESLD and HC. Full evaluation of lower limb muscle health is essential in ESLD in order to accurately assess sarcopenia and target future interventions.

Functional tests in women with patellofemoral pain: Which tests make a difference in physical therapy evaluation

BackgroundPatellofemoral pain (PFP) is characterized by anterior knee, which intensifies during functional activities that require the eccentric action of the quadriceps muscle, specially. In ths way, quantitatively measurable functional tests that simulate these activities should be included in the physical therapy evaluation. ObjectiveTo identify which functional tests are most indicated for the evaluation of women with PFD. MethodThis study evaluated 100 young women (50 with PFP), during the execution of the following functional performance tests: Triple hop, Vertical Jump, Single leg squat, Step Down, YBalance tests, Lunge test and running. Dynamic valgus was also assessed in the tests. The isometric muscle strength of the following muscle groups: hip abductors, extensors and lateral rotators, knee extensors, evertors, and plantar flexors were evaluated. Functional Perception were evaluated by Anterior Knee Pain Scale and Activities of Daily Living Scale. ResultsPFP group showed lower performance during the Y-Balance, triple hop, vertical jump tests and running. Was observed an increase in dynamic valgus during Triple Hop, Vertical Jump tests and running in PFP group, besides a poorer perception of function. For all lower limb muscle groups, the PFP group showed a reduction in peak isometric force. ConclusionThe YBalance, triple hop, vertical jump tests, and running should be included in the physical therapy evaluation, in addition to aspects of lower limb muscle strength.

Reliability of the Modified Ashworth Scale After Stroke for 13 Muscle Groups

ObjectiveTo evaluate the reliability of the protocol for administration of the Modified Ashworth Scale (MAS) for all commonly affected muscle groups after stroke. DesignA repeated-measures design was used in administration of MAS for 13 muscle groups on 2 assessment days. Intrarater reliability and interrater reliability (between 3 raters) was assessed. SettingInpatient rehabilitation. Participants30 patients, 1-19 months after stroke (age 55.1±13.5 years; N=30). InterventionsNot applicable. Main Outcome MeasureIntra- and interrater reliability of the muscle tone assessment protocol with MAS for 7 upper and 6 lower limb muscle groups compiled from previous studies; 1 modified and 4 originally described. The weighted kappa was calculated. ResultsThe most and the least frequently assigned MAS grades were 0 and 4, respectively. Agreement was the highest for grade 0 (49% within raters, 32% between raters). Intrarater reliability was good to excellent for upper limb (κ=0.71-0.94) and moderate to excellent for lower limb (κ=0.55-0.97) muscles. Interrater reliability was poor to good for upper limb (κ=0.25-0.66) and moderate for lower limb (κ=0.41-0.54) muscles. ConclusionsThe intrarater reliability of MAS was moderate for the hip flexors. The reliability results for the other 4 muscles studied anew after stroke were similar to the predetermined ones. The better intrarater reliability results confirmed previous findings. Because of the low interrater reliability, caution is needed in interpreting the results when reassessment is not possible by the same examiner. A well-described protocol for administering the MAS may lead to its standardization.

Effects of daily static stretch training over 6 weeks on maximal strength, muscle thickness, contraction properties, and flexibility.

Static stretch training (SST) with long stretching durations seems to be sufficient to increase flexibility, maximum strength (MSt) and muscle thickness (MTh). However, changes in contraction properties and effects on muscle damage remain unclear. Consequently, the objective of the study was to investigate the effects of a 6-week self-performed SST on MSt, MTh, contractile properties, flexibility, and acute response of creatine kinase (CK) 3 days after SST. Forty-four participants were divided into a control (CG, n = 22) and an intervention group (IG, n = 22), who performed a daily SST for 5 min for the lower limb muscle group. While isometric MSt was measured in leg press, MTh was examined via sonography and flexibility by functional tests. Muscle stiffness and contraction time were measured by tensiomyography on the rectus femoris. Additionally, capillary blood samples were taken in the pretest and in the first 3 days after starting SST to measure CK. A significant increase was found for MSt (p < 0.001, η 2 = 0.195) and flexibility in all functional tests (p < 0.001, η 2 > 0.310). Scheffé post hoc test did not show significant differences between the rectus femoris muscle inter- and intragroup comparisons for MTh nor for muscle stiffness and contraction time (p > 0.05, η 2 < 0.100). Moreover, CK was not significantly different between IG and CG with p > 0.05, η 2 = 0.032. In conclusion, the increase in MSt cannot be exclusively explained by muscular hypertrophy or the increased CK-related repair mechanism after acute stretching. Rather, neuronal adaptations have to be considered. Furthermore, daily 5-min SST over 6 weeks does not seem sufficient to change muscle stiffness or contraction time. Increases in flexibility tests could be attributed to a stretch-induced change in the muscle-tendon complex.

Normalization of EMG Signals: Optimal MVC Positions for the Lower Limb Muscle Groups in Healthy Subjects

Normalization of EMG Signals: Optimal MVC Positions for the Lower Limb Muscle Groups in Healthy Subjects

ASSESSMENT OF LOWER LIMB MUSCLE STRENGTH IN ATHLETES BY USING HAND-HELD DYNAMOMETER: A RELIABILITY STUDY

Background and Aims: Muscle strength is the key area to measure the functional status of an individual. Different tools and techniques has been used to detect strength differences and deficits. Hand- held dynamometer is one of the most affordable and handy tools used for this purpose. This study was designed to determine intra-rater reliability of hand- held dynamometer to measure muscle strength in different muscle groups of lower extremity of young athletes. It will further explore the reliability of hand- held dynamometer. Methodology: In this cross- sectional study young players of squash and badminton in the age group of 18-26 years were selected. The participants were recruited by non- probability convenience sampling technique. The strength of major muscle groups of lower limb was measured by a single male tester twice with gap through isometric make test of dynamometer. The intra-class correlation coefficient was then calculated for two readings of each muscle group by using SPSS version 21. Results: The intra- class correlation coefficient showed good to excellent reliability. The hip abductors, hip adductors, hip extensors of left side, knee flexors and knee extensors showed excellent reliability. Whereas, hip flexors, ankle plantar- flexors and dorsi-flexors of both sides showed excellent reliability at 95 % confidence interval. Conclusion: The isometric make test of dynamometer is a reliable tool for the objectification of strength of lower limb in young players participating in squash and badminton.

Reliability of Hand-Held Dynamometry for Measuring Force Production in People with Parkinson’s Disease

Purpose: People with Parkinson’s disease (PD) have impaired force production, which is associated with decreased mobility and falls risk. Reliable measurement of force production is important. Design: A repeated-measures, intra- and inter-rater reliability study was undertaken. Participants: 24 people with mild PD were measured by one or two raters. Outcome measures: Isometric force of the major upper and lower limb muscle groups was measured using hand-held dynamometry. Results: Fourteen participants were measured by the same rater on two occasions to determine intra-rater reliability. Ten participants were measured on two occasions by two different raters to determine inter-rater reliability. The intra-rater reliability of hand-held dynamometry was excellent in every muscle group, except the dorsiflexors. Intra-rater reliability was highest when measuring wrist extensors (ICC(2,1) = 0.98, 95% CI: 0.94 to 0.99) and lowest when measuring ankle dorsiflexors (ICC(2,1) = 0.87, 95% CI: 0.43 to 0.97). Inter-rater reliability was variable ranging from poor (wrist flexors: ICC(2,2) = -0.15, 95% CI: -1.14 to 0.60) to excellent (grip strength: ICC(2,2) = 0.97, 95% CI: 0.88 to 0.99). Conclusion: Hand-held dynamometry has good to excellent intra-rater reliability, but poor inter-rater reliability, for measuring force in the upper and lower limb in people with mild PD.

Associação entre medidas de força isocinética e desempenho funcional em pessoas idosas da comunidade

ABSTRACT Previous studies have shown an association between lower limb muscle strength and functional performance, but a dose-response relationship between the strength of each lower limb muscle group and performance in daily life activities in older adults has not been well established. Thus, this study aimed to investigate the association between isokinetic muscle strength of all eight major lower limb muscle groups and functional performance in community-dwelling older adults. The muscle strength of the plantar flexors and dorsiflexors of the ankle, flexors and extensors of the knee, and flexors, extensors, adductors, and abductors of the hip were evaluated using a Biodex System 4 Pro® isokinetic dynamometer. Functional performance was evaluated in 109 participants using the five-times sit-to-stand test (STS) and 4-meter usual walking speed (UWS). The multiple linear regression analyses showed that the hip abductors strength predicted 31.3% of the variability for UWS (p=0.011), and the knee extensors strength (p=0.015) predicted 31.6% of the variability for the STS. We conclude that hip abductors and knee extensors could be the key muscle groups involved in sit to stand and walking speed performance in older adults.

Acute Effect of Short Intensive Self-Myofascial Release on Jump Performance in Amateur Athletes: A Randomized Cross-Over Study.

Searching for effective methods to maximize physical performance that can be utilized during warm-ups is challenging in modern sports. This study aimed to investigate the effect of a short and intensive self-myofascial release (SI-SMR) on jumps in amateur, collegiate athletes. The study sample consists of 30 subjects with an average age of 21.8 years. The tests conducted included a squat jump (SJ), countermovement jump (CMJ), and drop jump (DJ). In the first week, half of the participants performed a standardized warm-up with additional short (15 s per lower limb muscle group) and intensive (20 reps/15 s) SMR and then performed jump tests. The other half performed a standard warm-up. The following week the groups switched interventions. The results revealed a tendency for all jump test parameters (height, force, and power), the reactive strength index, and stiffness to improve with SI-SMR, but the differences were small and insignificant. A dependent t-test for paired samples revealed that only SJ height improvement (+0.96 ± 2.63 cm) reached statistical significance (p = 0.04), but the small ES (ES = 0.14) could have attenuated this result. When a two-way mixed ANOVA was applied, the differences were insignificant. SI-SMR was ineffective in the direct improvement of jump performance. Although SI-SMR had no adverse effects, athletes should focus on specific preparations for sports competitions instead of using an SI-SMR protocol.

People with mild Parkinson's disease have impaired force production in upper limb muscles: A cross-sectional study.

There has been little examination of force production of the upper limb in people with Parkinson's disease (PD), despite its impact on activities of daily living and clear evidence that force production is significantly reduced in lower limb muscle groups. The aim of this study was to determine the force production of the major muscle groups of the upper limb in people with PD during the "on" phase after medication, compared with aged-matched neurologically-normal controls. A cross-sectional study was carried out. Thirty people with mild PD (Hoehn Yahr mean 1.1) and 24 age-matched neurologically-normal controls. Maximum isometric force production of the shoulder flexors, extensors, abductors, adductors, internal rotators and external rotators, elbow flexors and extensors, wrist flexors and extensors and hand grip using dynamometry. There was a significant impairment in force production in all upper limb muscle groups, compared with control participants, except in the wrist flexors. On average the deficit in force production was 22%, despite people with PD having mild disease, being physically active and being measured during the "on" phase of medication. The most severely affected muscle groups were the upper limb extensors. People with PD have a significant deficit in force production of the upper limb muscle groups compared with age-matched neurologically normal controls. Regular assessment of strength of the upper limb should be considered by clinicians and strengthening interventions could be implemented if a deficit is identified.

Reliability and validity of hand-held dynamometry for assessing lower limb muscle strength

BACKGROUND: Hand-held dynamometry (HHD) is used to assess muscle strength in various patient populations, but many variations in protocols exist. OBJECTIVE: First, to systematically develop a protocol of HHD for all lower limb muscle groups and evaluate intra-rater reliability; second, to validate HHD with fixed dynamometry for the knee flexor and extensor muscles. METHODS: Thirty healthy young adults (women: men – 15:15) participated in two testing sessions. HHD of 12 lower limb muscle groups was performed in both sessions, while fixed dynamometry of knee muscle groups was performed only in the second session. RESULTS: The intra-rater reliability of HHD was good for five muscle groups and excellent for seven muscle groups (ICC3, k= 0.80–0.96). The criterion validity of HHD ranged from very good to excellent for the knee flexors (r= 0.77–0.89) and from good to very good for the knee extensors (r= 0.65–0.78). However, peak moment values for the knee extensor muscles were underestimated by 32% (p&lt; 0.001). CONCLUSIONS: The proposed HHD protocol provides reliable and valid measurements of lower limb muscle isometric strength in healthy adults, which may also be used to test patients with mild muscle strength deficits. However, possible underestimation of absolute strength must be considered when interpreting the results of knee extensors or other large muscles.

Increase in Lower Limb Strength after Multimodal Pain Management in Patients with Low Back Pain.

Background and Objectives: The aim of the present study was to evaluate the efficacy of a multimodal pain therapy (MPM) regarding the objective parameter muscle strength of segment-dependent lower limb muscle groups before and after such a treatment. Materials and Methods: 52 patients with a history of low back pain and/or leg pain received standardized multimodal pain management. Strength of segment indicating lower limb muscles were assessed for each patient before and after ten days of treatment by handheld dynamometry. Results: Overall strength increased significantly from 23.6 kg ± 6.6 prior to treatment to 25.4 ± 7.3 after treatment, p ≤ 0.001. All muscle groups significantly increased in strength with exception of great toe extensors. Conclusions: Despite lower basic strength values at the beginning of treatment, all investigated muscle groups, except for the great toe extensors, showed a significant increase of overall strength after completion of the multimodal pain management concept. Increased overall strength could help with avoiding further need of medical care by supporting patients’ autonomy in daily life activities, as well as maintaining working abilities. Thus, our study is the first to show a significant positive influence on lower limb strength in patients with low back pain after a conservative MPM program.