Validity of the activPAL monitor to measure stepping activity and activity intensity: A systematic review

BACKGROUND

Accumulating step counts and engaging in moderate-to-vigorous intensity physical activity is positively associated with numerous health benefits. The activPAL is a thigh-worn monitor that is frequently used to measure physical activity.

RESEARCH QUESTION

Can the activPAL accurately measure stepping activity and identify physical activity intensity?

METHODS

We systematically reviewed validation studies examining the accuracy of activPAL physical activity outcomes relative to a criterion measure in adults (>18 years). Citations were not restricted to language or date of publication. Sources were searched up to May 16, 2021 and included Scopus, EMBASE, MEDLINE, CINAHL, and Academic Search Premier. The study was pre-registered in Prospero (ID# CRD42021248240). Study quality was determined using a modified Hagströmer Bowles checklist.

RESULTS

Thirty-nine studies (20 laboratory arms, 17 semi-structured arms, 11 uncontrolled protocol arms; 1272 total participants) met the inclusion criteria. Most studies demonstrated a high validity of the activPAL to measure steps across laboratory (12/15 arms), semi-structured (10/13 arms) and uncontrolled conditions (5/7 arms). Studies that demonstrated low validity were generally conducted in unhealthy populations, included slower walking speeds, and/or short walking distances. Few studies indicated that the activPAL accurately measured physical activity intensity across laboratory (0/6 arms), semi-structured (0/5 arms) and uncontrolled conditions (2/5 arms). Using the default settings, the activPAL overestimates light-intensity activity but underestimates moderate-to-vigorous intensity activity. The overall study quality was 11.5 ± 2.0 out of 19.

CONCLUSION

Despite heterogeneous methodological and statistical approaches, the included studies generally provide supporting evidence that the activPAL can accurately detect stepping activity but not physical activity intensity. Strategies that use alternative data processing methods have been developed to better characterize physical activity intensity, but all methods still underestimate vigorous-intensity activity.

Effects of workstation adjustment to reduce postural exposure and perceived discomfort among office workers - A cluster randomized controlled trial

This study aimed to evaluate the effects of workstation adjustment to reduce postural exposure and perceived discomfort among office workers in a cluster randomized controlled trial. Experimental (EG, n = 31) and control groups (CG, n = 30) were compared before (pre-intervention), immediately (post-intervention), and 3 months after (follow up) the intervention. EG received workstation adjustments and CG did not received the intervention. Postural exposure of head, upper back and upper arms was objectively measured by inclinometers. Overall level of perceived discomfort for the whole body was evaluated using a visual analogue scale (0-100 mm). EG showed a statistically significant reduction on the head (pre: 10.1°, SD 5.7°; post: 6.6°, SD 4.7°) and upper back flexion (pre: 15.4°, SD 10.7°; post: 10.4°, SD 8.4°) from pre to post-intervention. EG also showed a statistically significant reduction from pre (50.7°, SD 9.5°) to post-intervention (42.1°, SD 7.6°) and from pre to follow up (41.6°, SD 6.5°) on upper arm elevation. CG did not show any difference between evaluations. Perceived discomfort increased 7.2 (SD 2.0) mm in CG and decreased 22.1 (SD 2.2) mm in EG between pre and post intervention. The variation between pre intervention and follow up was 4.5 (SD 1.2) mm increase for the CG and 24.1 (SD 1.5) mm of reduction for the EG (P < 0.01). There was no significant difference for the post intervention and follow up for both groups (P > 0.05). The results show evidence of the workstation adjustment to reduce postural exposure and perceived discomfort among office workers.

Validity of the ActivPAL monitor to distinguish postures: A systematic review

BACKGROUND

Posture has been recently integrated into activity guidelines, advising people to limit their sedentary time and break up sedentary postures with standing/stepping as much as possible. The thigh-worn activPAL is a frequently used objective measure of posture, but its validity has only been investigated by individual studies and has not been systematically reviewed.

RESEARCH QUESTION

Can the activPAL accurately characterize different postures?

METHODS

A rigorous systematic review protocol was conducted, including multiple study screeners and determiners of study quality. To be included, validation studies had to examine the accuracy of an activPAL posture outcome relative to a criterion measure (e.g., direct observation) in adults (>18 years). Citations were not restricted to language or date of publication. Sources were searched on May 16, 2021 and included Scopus, EMBASE, MEDLINE, CINAHL, and Academic Search Premier. The study was pre-registered in Prospero (ID# CRD42021248240). Study quality was determined using a modified Hagströmer Bowles checklist. The results are presented narratively.

RESULTS

Twenty-four studies (18 semi-structured laboratory arms, 8 uncontrolled protocol arms; 476 participants) met the inclusion criteria. Some studies (5/24) incorporated dual-monitor (trunk: 4/5; shin: 1/5) configurations. While heterogenous statistical procedures were implemented, most studies (n = 22/24) demonstrated a high validity (e.g., percent agreement >90%, no fixed bias, etc.) of the activPAL to measure sedentary and/or upright postures across semi-structured (17/18 arms) and uncontrolled study designs (7/8 arms). Specific experimental protocol factors (i.e., seat height, fidgeting, non-direct observation criterion comparator) likely explain the divergent reports that observed valid versus invalid findings. The study quality was 11.3 (standard deviation: 2.3) out of 19.

CONCLUSION

Despite heterogeneous methodological and statistical approaches, the included studies generally provide supporting evidence that the activPAL can accurately distinguish between sedentary and standing postures. Multiple activPAL monitor configurations (e.g., thigh and torso) are needed to better characterize sitting versus lying postures.

Associations between physical function and device-based measures of physical activity and sedentary behavior patterns in older adults: moving beyond moderate-to-vigorous intensity physical activity

Background

Research supports that moderate-to-vigorous intensity physical activity (MVPA) is key to prolonged health and function. Among older adults, substantial changes to MVPA may be infeasible, thus a growing literature suggests a shift in focus to whole-day activity patterns.

Methods

With data from 795 older adults aged 65–100 in the Adult Changes in Thought Activity Monitoring study, we used linear regression to estimate associations between ActiGraph and activPAL measured activity patterns – including light intensity physical activity, steps, standing, and sedentary behaviors – and physical function as measured by a short Performance-based Physical Function (sPPF) score (range 0–12), a composite score based on three standardized physical performance tasks: gait speed, timed chair stands, and grip strength. We examined whether relationships persisted when controlling for MVPA or differed across age, gender, or quartiles of MVPA.

Results

In models unadjusted for MVPA, a 1-standard deviation (SD) increment of daily sitting (1.9 h more), mean sitting bout duration (8 min longer average), or time spent in sedentary activity (1.6 h more) was associated with ~ 0.3–0.4 points lower mean sPPF score (all p < 0.05). A 1-SD increment in daily steps (~ 3500 more steps) was associated with ~ 0.5 points higher mean sPPF score (95% CI: 0.22 to 0.73). MVPA adjustment attenuated all relationships. The association between physical function and steps was strongest among adults aged 75+; associations of worse function with greater sedentary behavior were more pronounced in participants with the lowest levels of MVPA.

Conclusions

We found associations between function and activity metrics other than MVPA in key subgroups, findings that support research on broader activity patterns and may offer ideas regarding practical intervention opportunities for improving function in older adults.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02163-4.

Smartphone Inclinometry Is a Valid and Reliable Tool for Measuring Frontal Plane Tibial Alignment in Healthy and Osteoarthritic Knees

OBJECTIVE

Frontal plane knee alignment plays an integral role in tibiofemoral knee osteoarthritis development and progression. Accessible methods for obtaining direct or indirect measures of knee alignment may help inform clinical decision making when specialized equipment is unavailable. The present study evaluated the concurrent validity, as well as intersession (within-rater) and interrater (within-session) reliability of smartphone inclinometry for measuring static frontal plane tibial alignment-a known proxy of frontal plane knee alignment.

METHODS

Twenty healthy individuals and 38 patients with knee osteoarthritis were measured for frontal plane tibial alignment by a pair of raters using smartphone inclinometry, manual inclinometry, and 3-dimensional motion capture simultaneously. Healthy participants were measured on 2 separate days. Bland-Altman analysis, supplemented with intraclass correlation coefficient (ICC)(2,k), was used to assess concurrent validity. ICC(2,k), SEM, and minimum detectable change with 95% confidence limits (MDC95) were used to assess measurement reliability.

RESULTS

Compared against motion capture, smartphone inclinometry measured frontal plane tibial alignment with a mean difference of 0.7 and 1.1 degrees (biased toward varus) for healthy participants and participants with knee osteoarthritis, respectively (ICC[2,k] ≥ 0.87). Smartphone inclinometry measurements demonstrated adequate intersession (within-rater) relative (ICC[2,k] = 0.91) and absolute (SEM = 0.7 degrees; MDC95 = 1.8 degrees) reliability, which outperformed manual inclinometry (ICC[2,k] = 0.85; SEM = 1.0 degrees; MDC95 = 2.6 degrees). Interrater (within-session) reliability of smartphone inclinometry was acceptable in both cohorts (ICC[2,k] = 0.93; SEM = 0.4 degrees to 1.2 degrees; MDC95 = 1.2 degrees to 3.2 degrees).

CONCLUSION

Smartphone inclinometry is sufficiently valid and reliable for measuring frontal plane tibial alignment in healthy individuals and patients with medial tibiofemoral knee osteoarthritis.

IMPACT

Smartphones are readily accessible by clinicians and researchers. Our assessment of measurement validity and reliability supports the use of smartphone inclinometry as a clinically available tool to measure frontal plane tibial alignment without medical imaging or specialized equipment.

A cartridge-based turning specimen holder with wireless tilt angle measurement for magnetic induction mapping in the transmission electron microscope

Magnetic induction mapping in the transmission electron microscope using phase contrast techniques such as off-axis electron holography and differential phase contrast imaging often requires the separation of the magnetic contribution to the recorded signal from the electrostatic contribution. When using off-axis electron holography, one of the experimental approaches that can be used to achieve this separation is to evaluate half of the difference between phase shift images that have been recorded before and after turning the sample over. Here, we introduce a cartridge-based sample mounting system, which is based on an existing on-axis tomography specimen holder and can be used to turn a sample over inside the electron microscope, thereby avoiding the need to remove the holder from the microscope to turn the sample over manually. We present three cartridge designs, which are compatible with all pole piece designs and can be used to support conventional 3-mm-diameter sample grids, Si₃N₄-based membrane chips and needle-shaped specimens. We make use of a wireless inclinometer that has a precision of 0.1° to monitor the sample holder tilt angle independently of the microscope goniometer readout. We also highlight the need to remove geometrical image distortions when aligning pairs of phase shift images that have been recorded before and after turning the sample over. The capabilities of the cartridge-based specimen holder and the turning approach are demonstrated by using off-axis electron holography to record magnetic induction maps of lithographically-patterned soft magnetic Co elements, a focused ion beam milled hard magnetic Nd-Fe-B lamella and an array of four Fe₃O₄ nanocrystals.

Measuring upper arm elevation using an inertial measurement unit: An exploration of sensor fusion algorithms and gyroscope models

Many sensor fusion algorithms for analyzing human motion information collected with inertial measurement units have been reported in the scientific literature. Selecting which algorithm to use can be a challenge for ergonomists that may be unfamiliar with the strengths and limitations of the various options. In this paper, we describe fundamental differences among several algorithms, including differences in sensor fusion approach (e.g., complementary filter vs. Kalman Filter) and gyroscope error modeling (i.e., inclusion or exclusion of gyroscope bias). We then compare different sensor fusion algorithms considering the fundamentals discussed using laboratory-based measurements of upper arm elevation collected under three motion speeds. Results indicate peak displacement errors of <4.5° with a computationally efficient, non-proprietary complementary filter that did not account for gyroscope bias during each of the one-minute trials. Controlling for gyroscope bias reduced peak displacement errors to <3.0°. The complementary filters were comparable (<1° peak displacement difference) to the more complex Kalman filters.

Intra- and inter-rater reliability of thoracic spine mobility and posture assessments in subjects with thoracic spine pain

Background

The thoracic spine (TS) has been neglected in the study of the spine despite its essential role in the stability and posture of the entire spinal complex. Therefore, there is an inevitable need to investigate the reproducibility of different thoracic spinal posture measures used in subjects with TS pain.

Methods

Thirty-two subjects (16 females and 16 males, mean age 39 years) were evaluated by two physiotherapists on the same day to gauge inter-rater reliability and on two consecutive days to gauge intra-rater reliability. TS posture was assessed by observation, and thoracic spine mobility was measured by manual assessment of segmental flexion and extension mobility in a seated position. Additionally, posterior-to-anterior accessory mobility in a prone position was assessed manually. Moreover, cervicothoracic flexion in a seated position, thoracic posture, and thoracic flexion and extension mobility in a standing position were assessed with a tape measure, and flexion and extension mobility in a seated position and TS posture in seated and standing positions were measured with an inclinometer. The intraclass correlation coefficient (ICC), standard error of measurement (SEM), mean difference (MD), Bland-Altman (B&A) plot features and coefficient of repeatability (CR) were calculated.

Results

The mean and standard deviation (SD) of the duration of TS pain was 22 (SD 45) months, with the intensity of pain being rated at 27 (SD 21) mm on a visual analogue scale (VAS). Intra-rater reliability was very strong (ICC ≥ 0.80) for the evaluation of seated and standing upper TS posture, standing whole TS posture and seated lower TS posture with an inclinometer. Moreover, TS posture evaluation with a measuring tape, posture inspection in a seated position, and manual assessment of segmental extension were found to have very strong intra-rater reliability. Inter-rater reliability was very strong for inclinometer measurements of standing and seated upper TS posture as well as standing whole TS posture.

Conclusion

Intra-rater reliability was higher than inter-rater reliability in most of the evaluated measurements. Overall, posture measurements with an inclinometer were more reliable than mobility measurements with the same instrument. The manual assessments can be used reliably when same evaluator performs the examination.

Trial registration

Clinical Trials, NCT01884818. Registered 24 June 2013, https://clinicaltrials.gov/ct2/show/NCT01884818?cond=thoracic+spine&cntry=FI&rank=1

Assessment of anterior-posterior spinal curvatures in children suffering from hypopituitarism

BACKGROUND

Body posture may be disordered by vestibular dysfunction, neurological disorders, problems with the distribution of muscle tone, brain injuries, and other dysfunctions. Growth hormone deficiency (GHD) can lead to many disorders, particularly of the musculoskeletal system. During treatment with recombinant human growth hormone (rhGH), an increase in muscle mass and an improvement in bone structure can be observed in children suffering from hypopituitarism from GHD.

METHODS

The study involved 33 children suffering from hypopituitarism with GHD (9 girls and 24 boys), aged 10-14 years old. Measurements of the magnitude of their anterior-posterior spinal curvatures were made using an inclinometer. The children were examined at the medianus of the sacrum bone, the Th12-L1 intervertebral area, and the C7-Th1 intervertebral area. In order to characterize the anterior-posterior curvature of the spine, the results were compared with the general norms reported by Saunders. Statistical calculations were carried out using the statistical package Statistica 10 PL.

RESULTS

Lumbar lordosis angles were higher in the patients currently receiving growth hormone (GH) treatment than in those who had yet to receive it. There is a statistically significant positive correlation between the length of growth hormone treatment and the alpha angle. There are also statistically significant correlations between age at the beginning of growth hormone therapy and the angle of lordosis. Statistically significant correlations were also seen between age at the beginning of growth hormone therapy and the alpha angle.

CONCLUSIONS

Although there may be changes in posture at the beginning of rhGH treatment, the sooner growth hormone therapy begins, the better the body posture. The longer the growth hormone treatment, the better the posture, as expressed by the alpha angle in the sagittal plane.

Evaluating the use of an electronic inclinometer in correcting rotational disorders of the hip in children

BACKGROUND

Femoral derotation osteotomies are commonly performed to correct rotational disorders of the hip in children. Surgical correction is typically assessed visually with the use of a goniometer or osteotomy template, but these methods have been shown to be inaccurate. In this study, we aimed to determine the accuracy of an electronic inclinometer in performing derotation osteotomies of 2 different magnitudes in comparison to commonly used visual techniques.

METHODS

We performed derotation osteotomies of 15°and 30° in a synthetic femur model using a goniometer, triangle osteotomy template, and electronic inclinometer. The degree of derotation was assessed by computed tomography (CT) and measured by a musculoskeletal radiologist. Statistical analyses included descriptive statistics, as well as t-test, analysis of variance (ANOVA), and Fisher's exact test to determine differences between osteotomy techniques.

RESULTS

We performed 40 proximal femoral derotation osteotomies. The mean difference from the planned derotation was 5.9° for the goniometer technique, 3.8° for the osteotomy triangle technique, and 3.2° for the electronic inclinometer technique (p-value = 0.048). There was no difference between the techniques for 15° derotation osteotomies (p-value = 0.28); however, there was a trend towards significance for 30° derotation osteotomies (p-value = 0.07). Fewer osteotomies had a difference greater than 3° from the planned derotation using the electronic inclinometer technique (p-value = 0.04).

CONCLUSIONS

The accuracy of derotation osteotomies can be improved with the use of an electronic inclinometer. This technology has the potential to improve surgical technique, minimize surgical error, and possibly improve patient outcomes.

Awkward trunk postures and their relationship with low back pain in hospital nurses

BACKGROUND

Low back pain (LBP) is the most common work-related musculoskeletal problem among healthcare workers including nurses. Awkward trunk postures have been recognized as one common problem in this groupOBJECTIVE:The aims of this study were to: a) continuously assess trunk postures for an entire shift work in various hospital wards, and b) examine the relationship between the duration of exposure to awkward trunk postures and the occurrence of low back pain (LBP) among nurses.

METHODS

Eighty nurses from eight wards in a hospital participated in this cross-sectional study. The prevalence of LBP was determined using the revised Nordic Musculoskeletal Questionnaire. Full-shift work trunk posture exposure was measured using an inclinometer.

RESULTS

The prevalence of LBP among hospital nurses was 72%. The highest percentage of time spent in awkward postures in the sagittal plane (trunk flexion ≥45°) and in the frontal plane (lateral bend ≥20°) was recorded in the general (65.6% ± 12.2) and orthopedic (48.4% ± 7.4) wards, respectively. Logistic regression analyses showed that the duration of exposure to awkward trunk postures had a significant relationship with LBP (P < 0.05).

CONCLUSIONS

The results highlight the potential risks of nursing job in terms of frequent and extreme trunk awkward postures, which may lead to the development of LBP. The findings can help to develop guidelines regarding prioritizing ergonomic interventions to reduce the prevalence of LBP among hospital nurses.

A randomised cross over study to evaluate the performance of a novel ankle dorsiflexion measurement device for novice users

Background

The ankle joint is a common site of musculoskeletal pathology. Measurement of its functional range of motion is a primary indicator for rehabilitation outcomes in therapy settings. The present study was designed to assess reliability and validity of a new standardised method using a D-Flex device to assess ankle range of motion.

Methods

A cohort of 20 healthy volunteers were recruited to measure the weight-bearing ankle range of motion using three assessment tools, namely, a goniometer, inclinometer and the D-Flex measurement devices. Repeated measures were performed both between and within observers for each device over a 48 h period. Performance evaluation of each device and their reliability was assessed using intra-class correlation coefficients and Bland and Altman plots.

Results

Although significant correlations (p < 0.05) were observed between devices, there were large mean differences in ankle range of motion values ranging from 4.3°-15.7°. The D-flex produced the highest inter- and intra-rater reliability (ICCs 0.76–0.95), compared to values of 0.55–0.85 and 0.32–0.71 for the goniometer and inclinometer, respectively. The Bland and Altman plots revealed a low mean observer difference for the D-Flex (mean difference = 0.7°), with the vast majority of data coincident within the 95% confidence intervals. For both the goniometer and inclinometer mean differences were higher, with values of 3.1° and 5.7° respectively.

Conclusion

The results of the present study provide evidence to support the use of the D-Flex system as a valid, portable, and easy to use alternative to the weight-bearing lunge test when assessing ankle dorsiflexion ROM in healthy participants.

Can the use of an inclinometer improve the positioning of the acetabular component in total hip arthroplasty?

Aims

Accurate placement of the acetabular component is essential in total hip arthroplasty (THA). The purpose of this study was to determine if the ability to achieve inclination of the acetabular component within the 'safe-zone' of 30° to 50° could be improved with the use of an inclinometer.

Patients and Methods

We reviewed 167 primary THAs performed by a single surgeon over a period of 14 months. Procedures were performed at two institutions: an inpatient hospital, where an inclinometer was used (inclinometer group); and an ambulatory centre, where an inclinometer was not used as it could not be adequately sterilized (control group). We excluded 47 patients with a body mass index (BMI) of > 40 kg/m², age of > 68 years, or a surgical indication other than osteoarthritis whose treatment could not be undertaken in the ambulatory centre. There were thus 120 patients in the study, 68 in the inclinometer group and 52 in the control group. The inclination angles of the acetabular component were measured from de-identified plain radiographs by two blinded investigators who were not involved in the surgery. The effect of the use of the inclinometer on the inclination angle was determined using multivariate regression analysis.

Results

The mean inclination angle for the THAs in the inclinometer group was 42.9° (95% confidence interval (CI) 41.7° to 44.0°; range 29.0° to 63.8°) and 46.5° (95% CI 45.2° to 47.7°; range 32.8° to 63.2°) in the control group (p < 0.001). Regression analysis identified a 9.1% difference in inclination due to the use of an inclinometer (p < 0.001), and THAs performed without the inclinometer were three times more likely to result in inclination angles of > 50° (odds ratio (OR) 2.8, p = 0.036). The correlation coefficient for the interobserver reliability of the measurement of the two investigators was 0.95 (95% CI 0.93 to 0.97).

Conclusion

The use of a simple inclinometer resulted in a significant reduction in the number of outliers compared with a freehand technique. Cite this article: Bone Joint J 2018;100-B:862-6.

The inter- and intrarater reliability and agreement for field-based assessment of scapular control, shoulder range of motion, and shoulder isometric strength in elite adolescent athletes

OBJECTIVES

To investigate the intra- and interrater reliability and agreement for field-based assessment of scapular control, shoulder range of motion (ROM), and shoulder isometric strength in elite youth athletes.

DESIGN

Test-retest reliability and agreement study.

SETTING

Eight blinded raters (two for each assessment) assessed players on field during two testing sessions separated by one week.

PARTICIPANTS

162 elite youth handball players with or without a history of previous shoulder pain within the preceding six months.

MAIN OUTCOME MEASURES

Kappa (κ) and prevalence-adjusted bias-adjusted kappa (PABAK) coefficients for scapular control reliability, and 95% limits of agreement (LOA) for ROM and strength agreement.

RESULTS

Scapular control demonstrated substantial to almost perfect reliability (κ 0.67 to 0.84, PABAK from 0.68 to 0.88). Mean strength values ranged from 0.9 N/kg to 1.6 N/kg, and LOAs ranged from -0.7 N/kg to 0.8 N/kg. Rotational strength revealed additionally systematic bias between and within rater. No or acceptable systematic bias were evident for ROM and abduction strength measures. Mean values and LOAs for ROM ranged between 39.9° to 52.3°, and from -12.6° to 9.9°, respectively.

CONCLUSIONS

Scapular control and ROM can be assessed on the field with acceptable reliability. The threshold for reliable measurements of isometric strength using handheld-dynamometers is high.

Smartphone applications for the evaluation of pathologic shoulder range of motion and shoulder scores-a comparative study

Hypothesis and background

Accurate measurement of range of motion (ROM) is important in evaluating a pathologic shoulder and calculating shoulder scores. The aim of this study was to establish the reliability and validity of different smartphone applications (apps) in assessing pathologic shoulder ROM and to determine whether differences in recorded ROM measurements affect calculated shoulder scores. The authors hypothesized that there is no difference between shoulder ROM assessment methods and calculated shoulder scores.

Methods

In this nonrandomized controlled clinical trial, ROM of 75 participants with a history of shoulder disease (21 women, 54 men) was assessed using a smartphone inclinometer and virtual goniometer, a standard goniometer, and clinicians' visual estimation. Shoulder strength was assessed, and Constant-Murley (CM) and University of California–Los Angeles (UCLA) shoulder scores were calculated.

Results

Independent of diagnosis or operation, all cases (except for passive glenohumeral abduction of unstable shoulders) showed excellent intraclass correlation coefficients (>0.84). Interobserver reliability was excellent for all ROM measures (intraclass correlation coefficient > 0.97). All modalities had excellent agreement to values attained with the universal goniometer. There were no differences for the calculated CM or UCLA scores between the modalities employed to measure ROM.

Conclusions

A smartphone inclinometer or virtual goniometer is comparable to other clinical methods of measuring pathologic shoulder ROM. Clinicians can employ smartphone applications with confidence to measure shoulder ROM and to calculate UCLA and CM scores. The apps are also available to patients and may be a useful adjunct to physiotherapy, especially in cases of limited access to health care services.

Accuracy of angular displacements and velocities from inertial-based inclinometers

The objective of this study was to evaluate the accuracy of various sensor fusion algorithms for measuring upper arm elevation relative to gravity (i.e., angular displacement and velocity summary measures) across different motion speeds. Thirteen participants completed a cyclic, short duration, arm-intensive work task that involved transfering wooden dowels at three work rates (slow, medium, fast). Angular displacement and velocity measurements of upper arm elevation were simultaneously measured using an inertial measurement unit (IMU) and an optical motion capture (OMC) system. Results indicated that IMU-based inclinometer solutions can reduce root-mean-square errors in comparison to accelerometer-based inclination estimates by as much as 87%, depending on the work rate and sensor fusion approach applied. The findings suggest that IMU-based inclinometers can substantially improve inclinometer accuracy in comparison to traditional accelerometer-based inclinometers. Ergonomists may use the non-proprietary sensor fusion algorithms provided here to more accurately estimate upper arm elevation.

The smartphone inclinometer: A new tool to determine elbow range of motion?

BACKGROUND

There are easily accessible tools on smartphones (APP) for measuring elbow range of motion (ROM). The purpose of this study is to evaluate the validity of a particular APP in determining elbow ROM in comparison with the commonly used goniometer (GON), surgeon estimation of range (EST) and measurement on X-ray (XR).

METHODS

The study included 20 patients (40 elbows). Flexion, extension, pronation and supination were measured using three different methods: EST, GON and APP. Radiographic measurements were taken using the average humeral diaphysis axis and dorsal midthird of ulna in flexion and extension.

RESULTS

The accuracy of the three different methods has been compared to GON using statistical analysis (ANOVA and paired samples test). There was no statistically significant difference for XR flexion measurement (mean of 2.8° ± 1.5°). The APP overestimated flexion (mean of 6.4° ± 1.0°), and EST underestimated it (mean of - 7.9° ± 1.1°). For extension, the mean difference was 2.8° ± 0.7° for EST and - 26.8° ± 3.1° for XR. The APP method did not significantly differ from GON. Supination accuracy was greater with EST (2.7° ± 1.7°) than with APP (5.9° ± 1.9°). There was no difference for pronation measurement with both EST and APP.

CONCLUSIONS

This study is the first comparing four measurement techniques of elbow ROM. Our results showed that EST was only accurate for forearm rotation. The XR scored the best for flexion but is less reliable for extension. Surprisingly, compared to GON, APP did not correlate as we expected for flexion and supination, but the other methods were also inaccurate. We found APP to be very useful to measure complete arc of motion (difference between maximal flexion and maximal extension).

LEVEL OF EVIDENCE

III, Retrospective review of a prospective cohort of elbow fracture patients: Diagnostic Study.

Full shift assessment of back and head postures in overhead crane operators with and without symptoms

OBJECTIVES

Prolonged sitting with a flexed back and neck is recognized as being associated with an increased risk of neck and back pain disorders among overhead crane operators. The aim of this study was to compare back and head postures over a full shift of work between operators who experience back and neck pain, and healthy operators.

METHODS

In a first phase, the prevalence of musculoskeletal symptoms was assessed using the Nordic questionnaire among 120 crane operators. Based on first phase results, 17 operators with back/neck disorders were matched with 15 healthy operators based on age and selected to participate in the second phase of the study. Postures and movements were continuously measured over an 8 h shift using inclinometers.

RESULTS

The highest 12-month prevalence of musculoskeletal disorders was found in the lower back, neck and knees. Case and control groups differed significantly in back and head flexion angles at the 50th percentiles APDF (p < 0.05). There was also a significant difference in the time spent working in an extreme posture of the back and head between groups (p < 0.05).

CONCLUSIONS

This is the first study to document work postures assumed during a full work shift and to compare postures between symptomatic and healthy overhead crane operators. Physical exposure in case group operators was characterized by more awkward and extreme postures in the back and head. The results of this study demonstrate that effective prevention strategies directed towards musculoskeletal disorders are required that address awkward work postures for overhead crane operators.

Considerations when using the activPAL monitor in field-based research with adult populations

Research indicates that high levels of sedentary behavior (sitting or lying with low energy expenditure) are adversely associated with health. A key factor in improving our understanding of the impact of sedentary behavior (and patterns of sedentary time accumulation) on health is the use of objective measurement tools that collect date and time-stamped activity information. One such tool is the activPAL monitor. This thigh-worn device uses accelerometer-derived information about thigh position to determine the start and end of each period spent sitting/lying, standing, and stepping, as well as stepping speed, step counts, and postural transitions. The activPAL is increasingly being used within field-based research for its ability to measure sitting/lying via posture. We summarise key issues to consider when using the activPAL in physical activity and sedentary behavior field-based research with adult populations. It is intended that the findings and discussion points be informative for researchers who are currently using activPAL monitors or are intending to use them. Pre-data collection decisions, monitor preparation and distribution, data collection considerations, and manual and automated data processing possibilities are presented using examples from current literature and experiences from 2 research groups from the UK and Australia.

The concurrent validity and reliability of the Leg Motion system for measuring ankle dorsiflexion range of motion in older adults

Background

New reliable devices for range of motion (ROM) measures in older adults are necessary to improve knowledge about the functional capability in this population. Dorsiflexion ROM limitation is associated with ankle injuries, foot pain, lower limb disorders, loss of balance, gait control disorders and fall risk in older adults. The aim of the present study was to assess the validity and reliability of the Leg Motion device for measuring ankle dorsiflexion ROM in older adults.

Methods

Adescriptive repeated-measures study was designed to test the reliability of Leg Motion in thirty-three healthy elderly patients older than 65 years. The subjects had to meet the following inclusion and exclusion criteria in their medical records: older than 65 years; no lower extremity injury for at least one year prior to evaluation (meniscopathy, or fractures) and any chronic injuries (e.g., osteoarthritis); no previous hip, knee or ankle surgery; no neuropathic alterations and no cognitive conditions (e.g., Alzheimer’s disease or dementia). Participants were recruited through the person responsible for the physiotherapist area from a nursing center. The subjects were evaluated in two different sessions at the same time of day, and there was a break of two weeks between sessions. To test the validity of the Leg Motion system, the participants were measured in a weight-bearing lunge position using a classic goniometer with 1° increments, a smartphone with an inclinometer standard app (iPhone 5S^®) with 1° increments and a measuring tape that could measure 0.1 cm. All testing was performed while the patients were barefoot. The researcher had ten years of experience as a physiotherapist using goniometer, tape measure and inclinometer devices.

Results

Mean values and standard deviations were as follows: Leg Motion (right 5.15 ± 3.08; left 5.19 ± 2.98), tape measure (right 5.12 ± 3.08; left 5.12 ± 2.80), goniometer (right 45.87° ± 4.98; left 44.50° ± 5.54) and inclinometer app (right 46.53° ± 4.79; left 45.27° ± 5.19). The paired t-test showed no significant differences between the limbs or between the test and re-test values. The test re-test reliability results for Leg Motion were as follows: the standard error of the measurement ranged from 0.29 to 0.43 cm, the minimal detectable difference ranged from 0.79 to 1.19 cm, and the intraclass correlation coefficients (ICC) values ranged from 0.97 to 0.98.

Conclusions

The results of the present study indicated that the Leg Motion device is a valid, reliable, accessible and portable tool as an alternative to the classic weight-bearing lunge test for measuring ankle dorsiflexion ROM in older adults.

Accuracy of inclinometer functions of the activPAL and ActiGraph GT3X+: A focus on physical activity

PURPOSE

The purpose of the study was to examine the accuracy of inclinometer functions of the ActiGraph GT3X+ (AG) (worn on the waist and wrist) and the activPAL (AP) in assessing time spent sitting, standing, and stepping.

METHODS

A total of 62 adults (age: 18-40 yrs; male:37; female:25) wore three activity monitors (AG waist, and AG wrist, and AP) while completing 15 different types of activities. The 15 activities were classified into 3 different postures (sitting, standing, and stepping) based on the directly observed behaviors. Minutes estimated from the inclinometers of the three monitors were directly compared to those from direct observation (criterion method) using mean absolute percent error (MAPE) values, effect sizes (Cohen's D), and equivalence testing.

RESULTS

The AP was more accurate than the both waist- and wrist-worn AG in both sitting and standing activities, but the AG was more accurate than the AP in stepping activity when the stepping activity was determined with 0.7 step/s threshold. Equivalence testing indicated that the time measured by the waist-, wrist-worn AG, and AP showed significant equivalence to the time in the equivalence zone (90% confidence interval: 2.7 to 3.3min) for 6, 5, and 7 activities, respectively.

CONCLUSIONS

The AP was reasonably accurate for detecting sitting, standing, and stepping, and the AG was very accurate for classifying stepping when the stepping activity was determined by the formula created by 0.7 step/s threshold. It is expected that the result of the study would contribute to performing movement pattern analyses and health promotion research for classifying activities.

Comparison of three activity monitors for estimating sedentary time among children

Background

Time spent sedentary appears to be associated with several health outcomes in adults, but findings are inconsistent in children. Further, the assessment of sedentary time represents a major challenge. The objectives of the present study were to determine whether 1) ActiGraph GT3X+, ActivPAL and SenseWear Armband Pro3 (SWA) provide comparable estimates of sedentary time in 9–12-year-old children, 2) these devices are valid compared with direct observation, and 3) ActivPAL discriminates between sitting and standing behavior.

Methods

The sample was 67 children. Data were collected during three consecutive days in November 2012. To test the activity monitors in contexts related to physical and sedentary activities commonly performed by children, the children participated in sessions of activity while sitting (watching television, playing video games and tossing a ball while sitting) and standing (musical chairs, active video gaming and tossing a ball) while wearing three different activity monitors at the same time. All activity sessions were observed by two researchers. Differences between monitors were determined using Friedman’s two-way analysis of variance by rank order.

Results

Minutes of estimated sedentary time differed across device brands during combined sitting activities: SWA vs. ActiGraph GT3X+ (P = 0.048), SWA vs. ActivPAL, (P < 0.001) and ActiGraph GT3X+ vs. ActivPAL (P = 0.002). Out of 12 min in total of combined recorded sitting activity, SWA reported a median of 6 min (95 % Confidence Interval [CI] = 5.0, 7.0), ActiGraph GT3X+ 7 min (7.0, 8.0) and ActivPAL 10 min (8.6, 10.8) as sedentary time. ActivPAL recorded 3.7 (2.4, 4.0) minutes of the non-sitting activities ‘musical chairs’, 4.0 (4.0, 4.0) minutes in ‘standing ball toss’; and 4.0 (2.7, 4.0) minutes in ‘active video gaming’ as sitting time.

Conclusion

Recorded sedentary time varied among the monitors GT3X+, SWA and ActivPAL, and misclassification of standing activities as sitting activities were apparent for ActivPAL in certain activities.

Exploring the context of sedentary behaviour in older adults (what, where, why, when and with whom)

BACKGROUND

Older adults are the most sedentary segment of the population. Little information is available about the context of sedentary behaviour to inform guidelines and intervention. There is a dearth of information about when, where to intervene and which specific behaviours intervention should target. The aim of this exploratory study was to obtain objective information about what older adults do when sedentary, where and when they are sedentary and in what social context.

METHODS

The study was a cross-sectional data collection. Older adults (Mean age = 73.25, SD ± 5.48, median = 72, IQR = 11) volunteers wore activPAL monitors and a Vicon Revue timelapse camera between 1 and 7 days. Periods of sedentary behaviour were identified using the activPAL and the context extracted from the pictures taken during these periods. Analysis of context was conducted using the Sedentary Behaviour International Taxonomy classification system.

RESULTS

In total, 52 days from 36 participants were available for analysis. Participants spent 70.1 % of sedentary time at home, 56.9 % of sedentary time on their own and 46.8 % occurred in the afternoon. Seated social activities were infrequent (6.9 % of sedentary bouts) but prolonged (18 % of sedentary time). Participants appeared to frequently have vacant sitting time (41 % of non-screen sedentary time) and screen sitting was prevalent (36 % of total sedentary time).

CONCLUSIONS

This study provides valuable information to inform future interventions to reduce sedentary behaviour. Interventions should consider targeting the home environment and focus on the afternoon sitting time, though this needs confirmation in a larger study. Tackling social isolation may also be a target to reduce sedentary time.

Validity of GT3X and Actiheart to estimate sedentary time and breaks using ActivPAL as the reference in free-living conditions

Sedentary time, specifically sitting/reclining, is a risk factor for many non-communicable diseases and premature mortality. Inclinometers have been used as a valid measurement of sedentary time and its patterns; however, there is a lack of information regarding the validity of alternative accelerometry and heart rate methods. The validity of GT3X and Actiheart in estimating changes in daily sedentary time and breaks, during free-living settings, using ActivPAL as the reference was examined. A crossover randomized control trial of an intervention that aimed to reduce ∼3 h/day of sitting time included 10 overweight/obese adults (37-65 years). Participants had a total of 74 valid days for the three devices (29 controls; 45 interventions). For ActivPAL, sedentary time was measured directly based upon posture (sitting/reclining); Actiheart, the presumed MET cutpoint for sedentary time (<1.5 METs) based on accelerometry+heart rate; GT3X, the traditional <100countsmin(-1). A break in sedentary time was defined as when the participants were above the aforementioned cutoffs. GT3X overestimated and Actiheart underestimated sedentary time (bias=135min; bias=-156min, respectively) and both methods overestimated breaks in sedentary time (bias=78; bias=235 breaks, respectively). The GT3X method was in better agreement with the ActivPAL sedentary time (r2=0.70; concordance correlation coefficient (CCC)=0.56) than the Actiheart (r2=0.24; CCC=0.31). The present results highlight the magnitude of potential errors in estimating sedentary time and breaks from common alternative methods other than ActivPAL. Because misclassification errors from the commonly used surrogates are potentially large, this raises concern that alternative methods used in many epidemiological observations may have underestimated the true effects caused by too much sitting (ClinicalTrials.govID:NCT02007681).

Intra- and inter-examiner reliability of goniometer and inclinometer use in Craig's test

[Purpose] The purpose of this study was to determine the inter- and intra-examiner reliability of measurement methods for femoral anterversion during Craig’s test. [Subjects and Methods] The study included 37 healthy participants (20 males and 17 females). Two novice examiners (Department of Physical Therapy students at Silla University) used three different methods to measure the femoral anterversion during Craig’s test: a goniometer, a goniometer with a laser beam, and an inclinometer. [Results] The intra-examiner reliability was high for both examiners with all three measurement methods, with scores of 0.82, 0.86, and 0.73 for examiner 1 and 0.74, 0.78, and 0.72 for examiner 2 for the goniometer, goniometer with the laser beam, and inclinometer, respectively. The inter-examiner reliability during Craig’s test was below moderate for both the goniometer (0.25) and inclinometer (0.27) and moderate for the goniometer with the laser beam (0.62). [Conclusion] This study found that Craig’s test using a goniometer with a laser beam had high intra-examiner reliability and moderate inter-examiner reliability. Clinically, these findings may supplement existing measurement skills and reduce the difficulty of locating the goniometer axis during Craig’s test.

Work with prolonged arm elevation as a risk factor for shoulder pain: a longitudinal study among young adults

This prospective study aimed at examining if work with prolonged arm elevation predicts shoulder pain among 41 young adults in their first years of working life. Fifteen hairdressers, 15 electricians, 5 students and 6 with various work were followed over a 2.5-year period (2006/7-2009). Arm elevation was measured with inclinometers during a full working day at baseline. Shoulder pain was reported at baseline and twice in the follow-up period. Data were analyzed by generalized estimating equations (GEE-analysis), stratified by gender and adjusted for time, mechanical workload, work demand, physical activity, tobacco use and prior shoulder pain. Work with prolonged arm elevation with angles >60° and >90° were associated with shoulder pain among women. Even though the shoulder pain levels are low the study suggests work with arms elevated as an early work-related risk factor among women, and indicates the importance of early prevention strategies.

Validation and calibration of the activPAL™ for estimating METs and physical activity in 4-6 year olds

OBJECTIVES

Examine the predictive validity of the activPAL™ metabolic equivalents equation, develop an activPAL™ threshold value to define moderate-to vigorous-intensity physical activities, and examine the classification accuracy of the developed moderate-to vigorous-intensity physical activities threshold value in 4- to 6-year-old children.

DESIGN

A sample of forty 4- to 6-year-old children from the Illawarra region in New South Wales, Australia were included in data analysis.

METHODS

Participants completed a ∼ 150-min room calorimeter protocol involving age-appropriate sedentary behaviors, light-intensity physical activities and moderate-to vigorous-intensity physical activities. activPAL™ accelerometer counts were collected over 15s epochs. Energy expenditure measured by room calorimetry and direct observation were used as the criterion measure. Predicted metabolic equivalents were calculated using the activPAL™ metabolic equivalents equation (activPAL™ software version 5.8.0). Predictive validity was evaluated using dependent-samples t-tests. Participants were randomly allocated into two groups to develop and cross-validate an intensity threshold for moderate-to vigorous-intensity physical activities. Receiver operating characteristic curve analysis was used to determine moderate-to vigorous-intensity physical activities threshold. The classification accuracy of the developed threshold was cross-validated using sensitivity, specificity, and area under the receiver operating characteristic-curve.

RESULTS

The activPAL™ metabolic equivalents equation significantly overestimated metabolic equivalents during sedentary behaviors and significantly underestimated metabolic equivalents for light-intensity physical activities, moderate-to vigorous-intensity physical activities and total metabolic equivalents compared to measured metabolic equivalents (all P<0.001). The developed threshold of ≥1418 counts per 15s resulted in good classification accuracy for moderate-to vigorous-intensity physical activities.

CONCLUSION

The current activPAL™ metabolic equivalents equation requires further development before it can be used to accurately estimate metabolic equivalents in preschoolers. The developed threshold exhibited acceptable classification accuracy for moderate-to vigorous-intensity physical activities; however studies cross-validating this moderate-to vigorous-intensity physical activities threshold in free-living preschool-aged children are recommended.

The reliability and concurrent validity of measurements used to quantify lumbar spine mobility: an analysis of an iphone® application and gravity based inclinometry

PURPOSEAIM: This purpose of this study was to investigate the reliability, minimal detectable change (MDC), and concurrent validity of active spinal mobility measurements using a gravity-based bubble inclinometer and iPhone® application. MATERIALSMETHODS: Two investigators each used a bubble inclinometer and an iPhone® with inclinometer application to measure total thoracolumbo-pelvic flexion, isolated lumbar flexion, total thoracolumbo-pelvic extension, and thoracolumbar lateral flexion in 30 asymptomatic participants using a blinded repeated measures design.

RESULTS

The procedures used in this investigation for measuring spinal mobility yielded good intrarater and interrater reliability with Intraclass Correlation Coefficients (ICC) for bubble inclinometry ≥ 0.81 and the iPhone® ≥ 0.80. The MDC90 for the interrater analysis ranged from 4° to 9°. The concurrent validity between bubble inclinometry and the iPhone® application was good with ICC values of ≥ 0.86. The 95% level of agreement indicates that although these measuring instruments are equivalent individual differences of up to 18° may exist when using these devices interchangeably.

CONCLUSIONS

The bubble inclinometer and iPhone® possess good intrarater and interrater reliability as well as concurrent validity when strict measurement procedures are adhered to. This study provides preliminary evidence to suggest that smart phone applications may offer clinical utility comparable to inclinometry for quantifying spinal mobility. Clinicians should be aware of the potential disagreement when using these devices interchangeably.

LEVEL OF EVIDENCE

2b (Observational study of reliability).

Short-term effect of muscle energy technique on pain in individuals with non-specific lumbopelvic pain: a pilot study

Muscle energy technique (MET) is a form of manual therapy frequently used to correct lumbopelvic pain (LPP), herein the patient voluntarily contracts specific muscles against the resistance of the clinician. Studies on MET regarding magnitude and duration of effectiveness are limited. This study was a randomized controlled trial in which 20 subjects with self-reported LPP were randomized into two groups (MET or control) after magnitude of pain was determined. MET of the hamstrings and iliopsoas consisted of four 5-second hold/relax periods, while the control group received a sham treatment. Tests for current and worst pain, and pain with provocation were administered at baseline, immediately following intervention and 24 hours after intervention. Separate 2x3 ANOVAs were used to assess results as change scores. Visual analog score (VAS) for worst pain reported in the past 24 hours decreased for the MET group (4.3mm+/-19.9, p=.03) and increased for the sham (control) group (17.1mm+/-21.2, p=.03). Subjects receiving MET demonstrated a decrease in VAS worst pain over the past 24 hours, thereby suggesting that MET may be useful to decrease LPP over 24 hours.