Reference values and reliability for lumbopelvic strength and endurance in asymptomatic subjects

Effectiveness of motor control exercise, aerobic walking, and muscle strengthening programs in improving outcomes in a subgroup of population with chronic low back pain positive for central sensitization: a study protocol for a randomized controlled trial

BACKGROUND

The role of pain sensitivity in the development and maintenance of chronic pain states, impaired executive functioning, and patient recovery is being investigated. Conditioned pain modulation (CPM) is widely used to measure musculoskeletal pain associated with central sensitization (CS). Despite the recommendations of many reviews and clinical practice guidelines that exercise programs reduce pain and disability, the overall confidence in these results is considered "critically low." The "active ingredient" of exercise programs and the dominant factor influencing CPM remain largely unknown. The objectives of this trial are to determine: • If different exercises cause different results on the CPM in a subgroup of people with chronic low back pain (CLBP) who are labeled as having CS pain, • If a program of exercise interventions for 12 weeks would alter executive functioning, quality of life (QoL), disability, and pain in persons with CLBP. • The relationship between patient characteristics, executive functions, CPM, and QoL METHODS: The trial is a randomized, controlled, multi-center study with four experimental groups and one healthy control group. Both the researchers and the people in the study will be blinded to the results. This paper describes the protocol for a trial examining the effects of 12-week individualized, twice-weekly exercise sessions lasting 30 to 60 min in persons with CLBP, who are positive for CS. Participants will be randomized to receive either patient education with motor control exercises (MCE), superficial strengthening (SS), aerobic exercises (AE), or patient education alone. Another group comprised of healthy volunteers will serve as controls. The primary outcomes are changes in CPM outcomes as measured by the cold pressor test (CPT). The secondary objectives are to evaluate executive functioning, pain, disability, quality of life, and spine muscle strength. The outcomes will be measured at 3 months and at a 6-month follow-up.

DISCUSSION

The outcomes of the study will help in gaining more information and evidence about exercise-induced analgesia from the perspective of CPM. Measuring exercise outcomes will aid in scientifically prescribing exercise prescriptions in people with CLBP. The study outcomes will also assist in identifying the characteristics of individuals who will respond or respond indifferently to exercises. Investigating the relationship between the study's various outcomes could provide information for future trials.

TRIAL REGISTRATION

Clinical Trials Registry of India (CTRI) identifier: CTRI/2022/03/041143. Registered on 16 March 2022.

Physical Performance and Mobility Tests Using Telehealth: A Feasibility Study With Athletes

CONTEXT

Physical performance tests (PPTs) and mobility tests have been widely used in sports rehabilitation. However, the feasibility of PPTs and mobility tests via telehealth is unknown.

OBJECTIVES

To verify the feasibility of PPTs and mobility tests to assess athletes via telehealth.

DESIGN

This is a feasibility study.

PARTICIPANTS

Athletes enrolled in a sports team or club for at least 2 years and with previous enrollment in a competitive league were recruited through advertisements on social media. The athletes included in this study (mean age = 25.9 y, from different sports) performed a battery of PPTs and mobility tests for the lower-extremity or upper-extremity and trunk, according to their sport modality.

MAIN OUTCOME MEASURE

The feasibility was assessed with recruitment, success, and dropout rates. In addition, athletes' perceptions of easiness, satisfaction, and safety during the lower-extremity or upper-extremity and trunk PPTs and mobility tests were assessed.

RESULTS

Seventy-three athletes were included, between January and April 2021: 41 were allocated to the lower-extremity and 32 to the upper-extremity and trunk PPTs and mobility test, according to their sports modality. The overall dropout rate was 20.55%; >89% of the athletes agreed that the PPTs and mobility tests via telehealth were easy to perform, >78% were satisfied, and >75% felt safe during the assessments.

CONCLUSION

This study indicated that these 2 batteries of performance and mobility tests via telehealth are feasible to assess the lower and upper-extremities, and the trunk of athletes, considering the adherence, athletes' perception of easiness, satisfaction, and safety.

Association of trunk and lower limb factors with shoulder complaints and sport performance in overhead athletes: A systematic review including GRADE recommendations and meta-analysis

OBJECTIVE

To identify the association of trunk and lower limb factors with shoulder complaints and sport performance in overhead athletes.

METHODS

Search performed at PubMed/Medline, Embase, CINAHL, LILACS, Cochrane, Web of Science and SPORTDiscus for observational studies. Methodological quality and strength of the evidence was assessed with the Newcastle-Ottawa Scale and GRADE. Meta-analysis and effects sizes analysis were calculated when possible.

RESULTS

Sixty-five studies were included. Low to very-low evidence suggests no association of trunk/lower limb strength, endurance, power, jump or balance with shoulder complaints and/or throwing performance. Athletes with shoulder complaints performed worse in trunk stability and endurance tests (mean difference: -6.83 (95%CI: -8.78, -4.88)). Athletes with high throwing performance presented better results in CMJ, horizontal jump, power measures and knee extension strength. For swimmers, there was no association of trunk/lower limb endurance with shoulder complaints (moderate evidence) and no association of balance and swimming performance (low evidence). Better trunk/lower limb strength, power and vertical jumps measures were associated with better swimming performance.

CONCLUSIONS

In methodologically similar studies, some trunk/lower limb outcomes are associated with shoulder complaint or sport/swimming performance. Results should be considered with caution and future studies should use better methodologies.

Patellofemoral pain over time: Protocol for a prospective, longitudinal study investigating physical and non-physical features

Background

This is a protocol for a prospective longitudinal study that aims to investigate: (1) group-by-time changes over a minimum of 15 months follow-up in patellofemoral pain (PFP) symptoms, biomechanical, muscle function, pain processing, and psychological features; (2) the extent to which changes in biomechanical, muscle function, pain processing, and psychological features are associated with changes in self-reported pain, physical performance measures, self-reported function, health-related quality of life (HRQOL), and physical activity level.

Methods

Individuals with PFP (n = 144) and control individuals (n = 85) without PFP were assessed at baseline. Outcomes assessed included: 3D kinematics and kinetics during single leg squat, step-down and single leg hop; maximal torque and rate of torque development of hip abductors and knee extensors/flexors; force steadiness of hip abductors and knee extensors; anterior and lateral trunk endurance; pressure pain thresholds at the center of patella and contralateral shoulder; kinesiophobia (Tampa Scale for Kinesiophobia); pain catastrophizing (Pain Catastrophizing Scale); worst self-reported pain (Visual Analogue Scale); physical performance measures (Single Leg Hop Test and Forward Step-Down Test); self-reported function (Anterior Knee Pain Scale); HRQOL (Medical Outcome Short-Form 36), and physical activity level (Baecke's Questionnaire). Follow-up assessments will be identical to the baseline and will be performed after a minimum of 15 months. Generalized linear mixed model (GLMM) will be used to investigate group-by-time differences. Linear regression models will be used to determine the extent to which changes in biomechanical, muscle function, pain processing, and psychological features are associated with changes in self-reported pain, physical performance measures, self-reported function, HRQOL, and physical activity level.

Discussion

Physical and non-physical features have been previously associated with PFP. However, the present study will be the first to investigate their integrated evolution as part of the natural history of PFP and its progression. In doing so, we will be able to determine their behavior in the long-term, as well as how they prospectively associate with each other and with clinical outcomes. Ultimately, this will provide a greater understanding of predictors of long-term outcome and possible targets for interventions.

Association between endurance of the trunk extensor muscles and balance performance in community-dwelling older adults: a cross-sectional analysis

Background/Aims

Previous research has disregarded the performance of the extensor muscle group of the trunk in balance control. The main purpose of this exploratory study was to assess the association between balance performance and endurance of the trunk extensor muscles in older adults, considering possible co-factors such as age and body mass index.

Methods

A correlational and predictive cross-sectional study was conducted with 61 community dwelling older adults (women n=45) with a mean age of 71 years (± standard deviation 6 years), and a mean body mass index of 28.1 kg/m2 (± standard deviation ± 4.7 kg/m2). The Berg Balance Scale was used to assess balance performance and Trunk Extensor Endurance Test to assess muscle endurance. Spearman's correlation coefficients (ρ) and single and multiple regression analyses were performed. Statistical significance was set at 0.05.

Results

The largest correlations were found between the Berg Balance Scale score and Trunk Extensor Endurance Test (ρ=0.41, P=0.001) and body mass index (ρ=−0.36, P=0.005). Muscle endurance alone predicted ~10% of the Berg Balance Scale score (R2=0.10, P=0.015). When combined with body mass index, it accounted for ~19% (R2=0.19, P=0.002). Adding the remaining variable (age) to the previous model increased the prediction by ~3% (R2=0.22, P=0.002).

Conclusions

Muscle endurance and body mass index significantly predicted (~19%) balance performance in older adults. Because these are modifiable factors, they should be routinely included in the screening of balance performance in older adults and addressed accordingly in preventive or rehabilitation programmes.

Altered muscle strength and flexibility among a subgroup of women with chronic nonspecific low back pain: Cross-sectional case-control study

OBJECTIVE

To compare muscle strength and flexibility among a subgroup of women with extension-related chronic nonspecific low back pain (CNLBP) with healthy controls.

METHODS

In this case-control study, 32 subjects with and without extension-related CNLBP were tested (n = 16 in each group). Gluteal, abdominal, paravertebral, and hamstring strength, along with hip flexor flexibility and hamstring flexibility were compared between groups. Data were analyzed using the Mann-Whitney test (p < .007).

RESULTS

The CNLBP subgroup displayed significantly lower strength of all muscles analyzed (p < .007), with the exception of gluteus medius. The flexibility of the hip flexors and hamstrings were not significantly reduced among the women with CNLBP (p > .007).

DISCUSSION

The present study showed that alterations in muscle strength, but not flexibility, partly consistent with those previously hypothesized but not objectively reported, were present among a subgroup of women with extension-related CNLBP. These results may have implications for the selection of therapeutic exercises among this subgroup of people with CNLBP.

What is Known About Muscle Strength Reference Values for Adults Measured by Hand-Held Dynamometry: A Scoping Review

•

Existing literature regarding handheld dynamometer (HHD) strength reference values is scarce.

•

The current literature includes gaps relating to strength units used and well-described protocols.

•

There is a critical need to develop HHD reference values in adults.

•

Considering the increased availability of high quality HHD, this issue is urgent.

Objective

Data Sources

Study Selection

Data Extraction

Data Synthesis

Conclusion

Trunk muscle endurance in individuals with and without patellofemoral pain: Sex differences and correlations with performance tests

OBJECTIVES

To compare trunk muscle endurance among females and males with and without patellofemoral pain (PFP), and to investigate the correlations between trunk muscle endurance and performance of the single leg hop test (SLHT) and forward step-down test (FSDT).

DESIGN

Cross-sectional.

SETTING

Laboratory-based study.

PARTICIPANTS

110 females and 38 males with PFP, 61 females and 31males without PFP.

MAIN OUTCOME MEASURES

Anterior and lateral trunk muscle endurance were assessed with the prone and bilateral side-bridge tests, respectively. Performance during the SLHT and FSDT was also assessed.

RESULTS

Lower anterior and lateral trunk muscle endurance were identified in females (p < .001; d = -0.74 to -0.86), but not in males (p ≥ .806; d = -0.04 to 0.05) with PFP as compared to sex-matched controls. Moderate to large, positive correlations between anterior and lateral trunk muscle endurance with performance in the SLHT and FSDT were identified in females (r = .27 to .50; p < .004) and males (r = 0.27 to 0.59; p < .031) with PFP and females without PFP (r = 0.26 to 0.40; p < .044).

CONCLUSION

Our findings highlight that assessing trunk muscle endurance is advised in females with PFP. Trunk muscle endurance of individuals with PFP may have a role in the performance of hopping and stepping down tasks.

Association between core stability and physical function, functional performance in patients with systemic sclerosis

OBJECTIVE

To investigate the association of core stability with physical function and functional performance in patients with systemic sclerosis (SSc).

METHODS

Forty patients who met the American College of Rheumatology / European League Against Rheumatism 2013 classification criteria for SSc were included in the cross-sectional study. For evaluation of core stability, trunk muscle endurance and trunk muscle strength were assessed. Trunk extensor and trunk flexor endurance tests were used for assessment of trunk muscle endurance. Trunk muscle strength was measured with a hand-held dynamometer and modified sit-up test. To measure physical function the Health Assessment Questionnaire Disability Index (HAQ-DI) and to measure functional performance 6-minute walking test (6MWT) and sit-to-stand test (STS) were used.

RESULTS

Patients with SSc had lower mean trunk extensor and flexor endurance test times (49.87 ± 30.81 and 32.17 ± 15.42 seconds, respectively), modified sit-up test repetition (17.42 ± 7.81) and trunk extensor and flexor muscle strength (7.48 ± 2.29 kg and 6.20 ± 1.68 kg, respectively) when compared to the reference values in healthy individuals. All measurements were used to evaluate core stability associated with HAQ-DI score, 6DMWT walking distance and STS test duration (all P < .05).

CONCLUSION

Patients with SSc have markedly reduced core stability and this negatively affects the physical function and functional performance. Therefore, this study highlights the importance of trunk muscle in patients with SSc. We suggest that not only upper-lower extremity muscles, but also trunk muscle strength and endurance should be measured and core stability exercises can be added to the training programs to maintain and/or improve physical functions and functional performance in SSc patients.

Trunk muscular endurance, lumbar spine mobility and hip flexibility in sailors with and without low back pain

Abstract Introduction: Low back pain is one of the most common injuries in sailors. Findings in the literature indicate that poor trunk endurance, flexibility and muscle strength are common in individuals with low back pain (LBP). Objective: Analyze trunk muscle endurance, lumbar spine mobility and hip flexibility in windsurfers with and without low back pain. Method: Sailors of both sexes with at least three years’ experience in the sport answered the Nordic Musculoskeletal Questionnaire and were submitted to Schober’s test, the passive straight leg raise (PSLR), the modified Thomas test, and isometric endurance assessment of the flexor, extensor and lateral flexor muscles of the torso. The sailors were divided into two groups (with and without LBP) and compared using the Student’s t-test or Mann Whitney U test. Results: Participants were 22 national-level sailors, 11 with low back pain (LBP) and 11 without (NLBP). The LBP group obtained longer holding times for the trunk extensors (p=0.028) and a greater difference in endurance between the right and left sides for lateral trunk muscles (p=0.030). Both groups obtained results below normative values in most of the tests performed. Conclusion: Sailors with low back pain exhibited greater trunk extensor endurance and a larger imbalance between lateral trunk muscles when compared to those with no LBP. Spinal mobility and hip flexibility were similar between groups.

Comparison of Hip and Lumbopelvic Performance Between Chronic Low Back Pain Patients Suited for the Functional Optimization Approach and Healthy Controls

STUDY DESIGN

Cross-sectional study.

OBJECTIVE

We explored the differences between chronic low back pain (CLBP) patients suited for the functional optimization approach and healthy controls in isometric hip-strength and lumbar-endurance tests and determined classificatory cutoff values for strength and endurance tests and ratios.

SUMMARY OF BACKGROUND DATA

To optimize the treatment effect for CLBP, some approaches have classified patients into homogeneous subgroups matched to specific treatments. We evaluated CLBP patients suited for the functional optimization approach, who seek care because they experience symptoms during activities with high physical demands, although they are relatively asymptomatic.

METHODS

Three hundred fifty subjects (healthy controls, 170; CLBP patients, 180) were stratified by age (18-40 and 41-65 yrs), sex, and physical activity level. The CLBP patients had an Oswestry Disability Index score < 20% and a Numeric Pain Rating Scale score < 3. The subjects underwent hip abductor, extensor, and flexor isometric strength tests; a deep abdominal function test; and lateral/frontal bridge and lumbar flexor/extensor endurance tests.

RESULTS

Relative to the healthy controls, the CLBP patients showed significantly (P > 0.05) higher strength scores in the hip flexor and deep abdominal function tests but lower endurance in the lateral and frontal bridge and lumbar flexor and extensor tests. The cutoff values of the lumbar flexor test and the lumbar flexor/extensor, lateral bridge/lumbar flexor, frontal bridge/lumbar flexor, and hip extensor/flexor test ratios showed acceptable accuracy (AUC = 0.84, 0.82, 0.79, 0.75, and 0.73, respectively).

CONCLUSION

In lumbopelvic and hip-performance tests, CLBP patients suited for the functional optimization approach showed differences from healthy controls. These patients could be discriminated from healthy controls on the basis of accurate cutoff values for strength and endurance tests and ratios, which should be considered in treatment decision-making when patients need to return to activities with higher physical demands.

LEVEL OF EVIDENCE

2.

Evaluation of Postural Stability and Transverse Abdominal Muscle Activity in Overweight Post-Stroke Patients: A Prospective, Observational Study

PURPOSE

Post-stroke hemiparesis has a significant impact on postural stability. The transversus abdominis (TrA) muscle contributes to the stability of the spine. The aim was to assess both the postural stability and the activity of the TrA muscle in overweight post-stroke patients.

METHODS

A group of 56 participants (61.12 ± 11.5 years) was divided into the study group (n=28 post-stroke patients, 63.7 ± 10.9 years) and control group (n= 23 healthy participants (58.5 ± 12.2 years). The Berg Balance Scale (BBS) and the Timed Up and Go Test (TUG) were used to evaluate postural stability and risk of falls. The Pressure Bio-Feedback Stabilizer (PBFS) device was used to assess functional stability.

RESULTS

Stroke had a significantly negative effect on the BBS (p < 0.001) and TUG (p = 0.001). The older age negatively affected the BBS (p = 0.001), TUG (p = 0.017), and the TrA muscle activity (p = 0.017). Higher values of body mass index (BMI) negatively affected the BBS (p = 0.028), however there were no changes of TUG results (p = 0.141), and the TrA muscle activity (p = 0.808). Also, BBS and TUG results were not associated with TrA muscle activity (p = 0.541 and p = 0.411, respectively). The results of the BBS, TUG, and PBFS did not differ according to gender (p < 0.05). Time from stroke negatively affected the TUG (p = 0.001), but had no effect on the TrA muscle activity (p < 0.05). The side of hemiparesis did not affect the postural stability (p < 0.05).

CONCLUSION

The consequences of a stroke have an essential negative effect on postural stability. Factors such as age, gender, time from stroke, and the side of the hemiparesis have not negatively affected postural stability in overweight post-stroke patients.

Reliability of two functional clinical tests to evaluate trunk and lumbopelvic neuromuscular control and proprioception in a healthy population

OBJECTIVES

The need to accurately assess trunk and lumbopelvic proprioception and neuromuscular control is widely accepted. However, based on current literature, there is a lack of reliable clinical tests to evaluate these aspects in clinical practice. The objective of this study is to investigate intra- and inter-tester reliability of the lateral step down test and the lumbopelvic position-reposition test in a healthy population.

METHODS

Protocol and scoring methods were developed for the lateral step down test and lumbopelvic position-reposition test, used to assess trunk and lumbopelvic neuromuscular control and proprioception respectively. Each test was performed once by thirty participants and video analysis for test scoring was performed. Three items on the lateral step down test were scored to evaluate neuromuscular control and, four items on the lumbopelvic position-reposition test were scored to evaluate proprioception. Aggregate scores for each test were calculated based on the separate item scores. Intraclass correlation coefficients and linear weighted kappa coefficients were determined for intra- and inter-tester reliability.

RESULTS

Based on the aggregate score, excellent intra- and inter-tester reliability (ICC (2,1)=0.73-0.88) was found for both tests. Moderate/almost perfect intra-and inter-tester agreement (K=0.62-0.91) was found for the separate items of the lateral step down test and fair/substantial agreement (K=0.25-0.76) for the items of the lumbopelvic position-reposition test.

CONCLUSION

Current testing protocol and scoring method for the lateral step down test is reliable. Adjustments for the scoring method of the lumbopelvic position-reposition test are warranted to improve reliability.