Validity and reliability of arm abduction angle measured on smartphone: a cross-sectional study

Reliability and validity of a method to measure trunk rotation angle from images using a camera and posture mirror

This study aimed to measure trunk rotation angle representations from images using a single camera combined with a posture mirror and to examine its reliability and validity. We applied a trunk rotation angle model using a tripod and markers simulating trunk rotation. We compared two methods of trunk rotation angle measurement: the conventional method from the superior aspect using a manual goniometer and a novel measurement method using images from a digital camera and a posture mirror. Measurement error was calculated as the average absolute error between the angle measured by the goniometer and that calculated from the camera and mirror image. The intraclass correlation coefficient (ICC 1, 1) and ICC (2, 1) were calculated as the intra-rater reliability and agreement between the measurement angles of the two methods, respectively. Systematic errors of the angles measured by the two methods were examined by a Bland‒Altman analysis. The mean (SD) of the mean absolute error was 1.17° (0.71°). ICC (1, 1) was 0.978, and ICC (2, 1) was 0.991. The Bland‒Altman analysis showed no systematic errors. The results suggest the validity and accuracy of our novel method to measure the angle of trunk rotation, which does not require high-cost equipment or a special environment.

The Validity and Reliability of a Smartphone Application for Measuring Wrist and Metacarpophalangeal Joint Motion

Background Accurate measurement of the range of motion (ROM) is crucial for guiding upper extremity rehabilitation. Inaccurate measurements can mislead clinicians and harm patient compliance. This study aimed to evaluate the validity and reliability of a smartphone application (Angulus) for measuring wrist and metacarpophalangeal (MCP) joint ROM. Methodology This study included 64 volunteers with no prior wrist injuries. The wrist flexion/extension, radial/ulnar deviation, and MCP joint flexion/extension ROM were assessed by an experienced physiotherapist (Assessor 1) using the Angulus and a standard two-arm goniometer. The validity of Angulus was evaluated by correlating it with the goniometer measurements using the Pearson correlation coefficient. For the reliability analysis, an inexperienced biomedical engineer (Assessor 2) performed the same measurements using Angulus twice in different sessions, in addition to Assessor 1. The intra-rater and inter-rater reliability were tested using the intraclass correlation coefficient. Results The mean age of the participants was 29.5 ± 8.2 years, with 62% being female. The validity of the Angulus app measurements was indicated by the adequate to excellent correlation between the Angulus and goniometer measurements (ranging from 0.44 to 0.81). The intra-rater reliability of the Angulus app was excellent for Assessor 1 (ranging from 0.76 to 0.90) and adequate to excellent for Assessor 2 (ranging from 0.71 to 0.88). The inter-rater reliability of Angulus was excellent (ranging from 0.91 to 0.96). Conclusions Angulus is a valid and reliable method to measure the wrist and MCP joint ROM.

Algorithmic assessment of shoulder function using smartphone video capture and machine learning

Tears within the stabilizing muscles of the shoulder, known as the rotator cuff (RC), are the most common cause of shoulder pain-often presenting in older patients and requiring expensive advanced imaging for diagnosis. Despite the high prevalence of RC tears within the elderly population, there is no previously published work examining shoulder kinematics using markerless motion capture in the context of shoulder injury. Here we show that a simple string pulling behavior task, where subjects pull a string using hand-over-hand motions, provides a reliable readout of shoulder mobility across animals and humans. We find that both mice and humans with RC tears exhibit decreased movement amplitude, prolonged movement time, and quantitative changes in waveform shape during string pulling task performance. In rodents, we further note the degradation of low dimensional, temporally coordinated movements after injury. Furthermore, a logistic regression model built on our biomarker ensemble succeeds in classifying human patients as having a RC tear with > 90% accuracy. Our results demonstrate how a combined framework bridging animal models, motion capture, convolutional neural networks, and algorithmic assessment of movement quality enables future research into the development of smartphone-based, at-home diagnostic tests for shoulder injury.

The concurrent validity and reliability of virtual reality to measure shoulder flexion and scaption range of motion

BACKGROUND

Shoulder pain commonly has a detrimental impact on patient's work and social activities. Although pain is the most common reason for seeking care, a reduction in shoulder range of motion (ROM) is another common impairment. ROM assessment is used as an evaluation tool and multiple methods are available to measure shoulder ROM. Virtual reality (VR) has been introduced into shoulder rehabilitation, mostly when exercise and ROM measurement is indicated. This study evaluated the concurrent validity and system reliability of active ROM measurements of VR for people with and without shoulder pain.

METHODS

Forty volunteers participated in this study. Virtual goniometry was used to assess active shoulder ROM. Participants performed flexion and scaption to six predetermined angles. Measurements from the VR goniometer and smartphone inclinometers were recorded simultaneously. To assess reliability, two identical test sequences were performed.

RESULTS

The concurrent validity ICCs were 0.93 for shoulder flexion and 0.94 for shoulder scaption. The VR goniometer application on average systematically overestimated the ROM compared to the smartphone inclinometer. The mean difference between goniometer values was -11.3 degrees for flexion and -10.9 for scaption. The system reliability was excellent with an overall ICC of 0.99 for the flexion movements and 0.99 for the scaption movements.

CONCLUSION

Although the VR system demonstrated excellent reliability, and high ICC's for concurrent validity, the large range between the lower and upper 95% CI limits suggests it lacks measurement precision. This suggests VR, as used in this study, should not be used interchangeably with other measurement tools. CONTRIBUTION OF THE PAPER.

The Intra- and Inter-Rater Reliability of a Variety of Testing Methods to Measure Shoulder Range of Motion, Hand-behind-Back and External Rotation Strength in Healthy Participants

This study determined the intra- and inter-rater reliability of various shoulder testing methods to measure flexion range of motion (ROM), hand-behind-back (HBB), and external rotation (ER) strength. Twenty-four healthy adults (mean age of 31.2 and standard deviation (SD) of 10.9 years) without shoulder or neck pathology were assessed by two examiners using standardised testing protocols to measure shoulder flexion with still photography, HBB with tape measure, and isometric ER strength in two abduction positions with a hand-held dynamometer (HHD) and novel stabilisation device. Intraclass correlation coefficient (ICC) established relative reliability. Standard error of measurement (SEM) and minimum detectable change (MDC) established absolute reliability. Differences between raters were visualised with Bland-Altman plots. A paired t-test assessed for differences between dominant and non-dominant sides. Still photography demonstrated good intra- and inter-rater reliability (ICCs 0.75-0.86). HBB with tape measure demonstrated excellent inter- and intra-rater reliability (ICCs 0.94-0.98). Isometric ER strength with HHD and a stabilisation device demonstrated excellent intra-rater and inter-rater reliability in 30° and 45° abduction (ICCs 0.96-0.98). HBB and isometric ER at 45° abduction differed significantly between dominant and non-dominant sides. Standardised shoulder ROM and strength tests provide good to excellent reliability. HBB with tape measure and isometric strength testing with HHD stabilisation are clinically acceptable.

Comparison of Shoulder Motion Measurements by Visual Estimate, Goniometer and Motion Capture

BACKGROUND

Brachial plexus birth injuries (BPBI) can result in lasting impairments of external rotation and cross-body adduction (CBA) that disrupt functional activities such as dressing, grooming, or throwing a ball. The purpose of this study was to compare the quantification of shoulder humerothoracic (HT) external rotation (ER), and glenohumeral (GH) CBA by 3 methods - physician visual estimate, goniometer measurement by an occupational therapist, and motion capture.

METHODS

Twenty-six patients with BPBI (average age of 9.9±3.2 y) participated in this study. Mallet scores and visual estimates of passive HT ER and GH CBA were recorded by a physician. The passive measures were repeated by an occupational therapist using a goniometer while motion capture measures were simultaneously collected. Active HT ER was also measured by motion capture. The passive measures were compared with analyses of variance with repeated measures, intraclass correlations, and Bland-Altman plots. External rotation Mallet scores determined by motion capture and by the physician were compared.

RESULTS

The measures of GH CBA were not statistically different and demonstrated good agreement, but substantial variation. For HT ER, all measures were significantly different and demonstrated poor agreement and substantial variation. When the joint angles measured by motion capture were used to determine the Mallet score, 79% of external rotation Mallet scores assigned by the physician were incorrectly categorized, with the physician always scoring the participant higher than predicted motion capture Mallet score.

CONCLUSIONS

Both GH CBA and HT ER measures demonstrated substantial variability between measurement types, but only HT ER joint angles were significantly different. In addition, more than three-quarters of external rotation Mallet scores were misclassified by the physician. Motion capture measurements offer the benefit of less susceptibility to patients' compensatory and/or out-of-plane movements and should be considered for clinical assessment of shoulder range of motion in children with BPBI. If motion capture is unavailable, the use of a goniometer provides more accurate clinical measures of shoulder motion than visual estimates and care should be taken to minimize and account for compensatory movement strategies.

LEVEL OF EVIDENCE

Level IV Case series.

Comparison of Motion Analysis Systems in Tracking Upper Body Movement of Myoelectric Bypass Prosthesis Users

Current literature lacks a comparative analysis of different motion capture systems for tracking upper limb (UL) movement as individuals perform standard tasks. To better understand the performance of various motion capture systems in quantifying UL movement in the prosthesis user population, this study compares joint angles derived from three systems that vary in cost and motion capture mechanisms: a marker-based system (Vicon), an inertial measurement unit system (Xsens), and a markerless system (Kinect). Ten healthy participants (5F/5M; 29.6 ± 7.1 years) were trained with a TouchBionic i-Limb Ultra myoelectric terminal device mounted on a bypass prosthetic device. Participants were simultaneously recorded with all systems as they performed standardized tasks. Root mean square error and bias values for degrees of freedom in the right elbow, shoulder, neck, and torso were calculated. The IMU system yielded more accurate kinematics for shoulder, neck, and torso angles while the markerless system performed better for the elbow angles. By evaluating the ability of each system to capture kinematic changes of simulated upper limb prosthesis users during a variety of standardized tasks, this study provides insight into the advantages and limitations of using different motion capture technologies for upper limb functional assessment.

The Reliability of the Microsoft Kinect and Ambulatory Sensor-Based Motion Tracking Devices to Measure Shoulder Range-of-Motion: A Systematic Review and Meta-Analysis

Advancements in motion sensing technology can potentially allow clinicians to make more accurate range-of-motion (ROM) measurements and informed decisions regarding patient management. The aim of this study was to systematically review and appraise the literature on the reliability of the Kinect, inertial sensors, smartphone applications and digital inclinometers/goniometers to measure shoulder ROM. Eleven databases were screened (MEDLINE, EMBASE, EMCARE, CINAHL, SPORTSDiscus, Compendex, IEEE Xplore, Web of Science, Proquest Science and Technology, Scopus, and PubMed). The methodological quality of the studies was assessed using the consensus-based standards for the selection of health Measurement Instruments (COSMIN) checklist. Reliability assessment used intra-class correlation coefficients (ICCs) and the criteria from Swinkels et al. (2005). Thirty-two studies were included. A total of 24 studies scored "adequate" and 2 scored "very good" for the reliability standards. Only one study scored "very good" and just over half of the studies (18/32) scored "adequate" for the measurement error standards. Good intra-rater reliability (ICC > 0.85) and inter-rater reliability (ICC > 0.80) was demonstrated with the Kinect, smartphone applications and digital inclinometers. Overall, the Kinect and ambulatory sensor-based human motion tracking devices demonstrate moderate-good levels of intra- and inter-rater reliability to measure shoulder ROM. Future reliability studies should focus on improving study design with larger sample sizes and recommended time intervals between repeated measurements.

Reliability of measurement using Image J for reach distance and movement angles in the functional reach test

[Purpose] The purpose of this study was to examine the test-retest reliability and minimal detectable change (MDC) of reach distance and movement angle analyses using Image J. [Participants and Methods] Thirty-eight healthy young males performed the functional reach test (FRT) twice, and their reach movements were recorded using a digital video camera. Image J was used to combine the digital photographs taken at the start position and maximum reach and to measure each movement. The measurements recorded were the movement distance of the third metacarpal bone (reach distance), anterior-superior iliac spine, and trochanter major, and the angles recorded were the acromion-malleolus lateralis, acromion-trochanter major, and trochanter major-malleolus lateralis. The reliability of all the measurements was analyzed using intraclass correlation coefficients (ICCs), Bland-Altman plots, and MDCs. [Results] The ICCs (1, 1) were >0.80 for all the outcomes. The Bland-Altman analysis revealed no systematic bias in any outcome. The MDC of reach distance was 18.3 mm. [Conclusion] Measurement using Image J for reach distance and movement angles in the FRT showed acceptable high test-retest reliability. Measurement of the FRT and the MDC calculated in this study could be used as a reference for further research.

Application of machine learning to the identification of joint degrees of freedom involved in abnormal movement during upper limb prosthesis use

To evaluate movement quality of upper limb (UL) prosthesis users, performance-based outcome measures have been developed that examine the normalcy of movement as compared to a person with a sound, intact hand. However, the broad definition of “normal movement” and the subjective nature of scoring can make it difficult to know which areas of the body to evaluate, and the expected magnitude of deviation from normative movement. To provide a more robust approach to characterizing movement differences, the goals of this work are to identify degrees of freedom (DOFs) that will inform abnormal movement for several tasks using unsupervised machine learning (clustering methods) and elucidate the variations in movement approach across two upper-limb prosthesis devices with varying DOFs as compared to healthy controls. 24 participants with no UL disability or impairment were recruited for this study and trained on the use of a body-powered bypass (n = 6) or the DEKA limb bypass (n = 6) prosthetic devices or included as normative controls. 3D motion capture data were collected from all participants as they performed the Jebsen-Taylor Hand Function Test (JHFT) and targeted Box and Blocks Test (tBBT). Range of Motion, peak angle, angular path length, mean angle, peak angular velocity, and number of zero crossings were calculated from joint angle data for the right/left elbows, right/left shoulders, torso, and neck and fed into a K-means clustering algorithm. Results show right shoulder and torso DOFs to be most informative in distinguishing between bypass user and norm group movement. The JHFT page turning task and the seated tBBT elicit movements from bypass users that are most distinctive from the norm group. Results can be used to inform the development of movement quality scoring methodology for UL performance-based outcome measures. Identifying tasks across two different devices with known variations in movement can inform the best tasks to perform in a rehabilitation setting that challenge the prosthesis user’s ability to achieve normative movement.

Revisiting the Beighton Criteria: Does Ligamentous Laxity Testing Correlate With Shoulder Range of Motion Norms in a North American, Pediatric Population?

BACKGROUND

Ligamentous laxity testing using the Beighton score is frequently used as part of the pediatric shoulder examination. However, the relationship between generalized ligamentous laxity (GLL) and shoulder range of motion (ROM) remains unexamined in children, and normative data for these clinical tests have not been well established. In this study, we establish normative data for shoulder range of motion and GLL in a healthy, diverse pediatric population and investigate whether Beighton testing correlates with shoulder ROM in children.

METHODS

Healthy subjects age 2 to 18 years with isolated lower extremity complaints were recruited. Passive shoulder ROM measurements for forward flexion (FF), abduction (ABD), internal rotation (IR), external rotation (ER), and extension (EXT) were obtained using a long-armed goniometer. The Beighton score was obtained, with a positive test defined as ≥5. Descriptive statistics were used to stratify data on the basis of age and sex. Interclass correlation coefficients (ICCs) were calculated. Spearman's r was calculated to determine correlations between the Beighton score and shoulder ROM. Predictive indices of a positive Beighton test to identify patients with high shoulder mobility (ROM in the top 15 percentile, or 1 SD above the mean) were calculated.

RESULTS

A total of 202 subjects were enrolled and evaluated. Passive ROM norms by age and sex were determined. Intraclass correlation coefficients for all shoulder ROM measurements were substantial to excellent. Female individuals had greater ROM than age-matched male individuals, but this trend was largely statistically insignificant. Pearson's correlation between age and shoulder ROM was significant for FF, ABD, EXT, and ER (r=-0.52 to -0.20, P<0.001). Based on a Beighton score of ≥5, the prevalence of GLL was 10% in male and 15% in female individuals. Spearman's correlation between Beighton score and shoulder ROM was significant for 3 of 5 ROM measurements: FF, ER, and EXT (r=0.30 to 0.39, P<0.001).

CONCLUSIONS

Normative pediatric shoulder ROM and joint laxity data have been established in a healthy, diverse population of children. Beighton testing exhibits only a weak to moderate correlation, despite statistical significance, with shoulder ROM and is poorly predictive for high ROM in children.

LEVEL OF EVIDENCE

Level I- Diagnostic.

Assessing the concurrent validity and reliability of an iPhone application for the measurement of range of motion and joint position sense in knee and ankle joints of young adults

OBJECTIVE

To analyze the concurrent validity and reliability of an iPhone application for assessing range of motion (ROM) and joint position sense (JPS) in ankle and knee joints.

DESIGN

Cross-sectional study.

SETTING

Sport laboratory.

PARTICIPANTS

Twenty healthy and physically active volunteers.

INTERVENTIONS

All participants performed a ROM and a JPS test in ankle and knee joints, which were simultaneously evaluated with photo-analysis and the iPhone application.

MAIN OUTCOMES MEASURES

A total of 80 angles were obtained with the iPhone app and the photo-analysis and compared for concurrent validity. Reliability was evaluated through re-scoring of images with the iPhone app by two different testers.

RESULTS

Very high correlation was observed between both methods for ankle and knee ROM and knee JPS (r > 0.90), and high correlation for ankle JPS (r = 0.71-0.90), while Bland-Altman plots showed absolute agreement for all the variables. Inter- and intra-tester reliability was perfect for all the variables (ICC > 0.81), except for the inter-tester reliability of ankle JPS, which was substantial (ICC = 0.61-0.81).

CONCLUSIONS

This new iPhone application is valid and reliable for measuring ankle and knee ROM and JPS, although special attention is needed during ankle evaluation to avoid errors.

DigitalROM: Development and validation of a system for assessment of shoulder range of motion

Assessing shoulder mobility is traditionally performed by a clinician using a goniometer, however this method suffers from inter-rater reliability issues. Wearable inertial sensors, image-based systems and 3D-cameras are proposed to objectively quantify shoulder range of motion (ROM). Standardised data collection platforms are required to ensure the consistency of measurements. This paper describes DigitalROM, a Microsoft Kinect 3D camera based system, and a standardised data collection protocol for shoulder ROM assessment optimised for multi-centre clinical trial deployments. DigitalROM is shown to compare very well against image-based ground truth measures (R²= 0.98 and RMSE≤7°) and shows slightly better performance than inertial sensor based ROM measurements (R²= 0.96 and RMSE≤9°). Additionally, DigitalROM offers the ability to ensure patient adherence to the movement protocol during data collection.

The validity and reliability of DrGoniometer, a smartphone application, for measuring forearm supination

STUDY DESIGN

Clinical measurement (reliability and validity) study.

INTRODUCTION

Forearm supination is important in many daily activities and is thus measured by therapists and researchers usually with a universal goniometer. DrGoniometer, a SmartPhone application, has been validated for other joint angles in the body.

PURPOSE OF THE STUDY

To establish the reliability and validity of DrGoniometer (CDM S.r.L, Cagliari, Italy) for measuring forearm supination in healthy populations and those with forearm fractures.

METHODS

Participants had sustained a distal radius fracture that was treated non-surgically. Forearm supination of the participant's fractured (n = 30) and healthy forearm (n = 30) was measured using DrGoniometer and the universal goniometer by two assessors. The assessors were blinded to each other's measurements and their own previous measurements. Reliability was established by calculating Intra-class Correlation Coefficients, standard error of measurement and minimal detectable change. The validity of DrGoniometer was established against the universal goniometer using Pearson's correlation co-efficient.

RESULTS

Intra-rater reliability of both DrGoniometer and the universal goniometer was high for both fractured and healthy forearms (ICCs ranged from 0.74-0.88). Inter-rater reliability of both DrGoniometer and the universal goniometer was also high in the fractured forearm group (0.76 and 0.72 respectively), but low in the healthy forearm group (0.34 and 0.42 respectively). Correlation between the tools was excellent across the fractured and healthy forearm groups (0.94 and 0.93 respectively).

DISCUSSION

Both goniometers demonstrated good-to-excellent intrarater and iner-rater reliability except in the healthy forearm group where both goniometers demonstrated poor inter-rater reliability which could be due to assessor instructions. The speed the photo can be taken and the digital record obtained are valuable aspects of DrGoniometer.

CONCLUSION

DrGoniometer is a valid, alternate tool for measuring forearm supination.

[Commercial mobile applications in the therapeutic approach to stroke: Review in main application repositories and scientific evidence]

OBJECTIVE

Stroke is the leading cause of physical disability in the adult population. Technology at the service of medicine provides new solutions for the assessment, treatment, and monitoring of subjects with neurological disorders. Therefore, the aim of this study was to review the use of commercial mobile applications in the therapeutic approach of subjects who have suffered a stroke, as well as to analyze if there is scientific evidence on their use.

METHODS

A search of specific apps for the therapeutic approach to stroke, as well as its possible clinical aftereffects, in the main applications repositories was made: "Google Play" and "App Store". Besides, the possible scientific evidence for each app obtained was analyzed using the following databases: Web of Science, Pubmed, ScienceDirect, Scopus and Google Scholar.

RESULTS

A total of 45 apps were obtained meeting the criteria established in the study. These were subdivided into different categories: assessment tools (13), therapeutic exercise program (8) perception of laterality and body scheme (7), management of secondary disorders (7), mobility, dexterity and manual coordination (5) and postural correction and ergonomics (5). From the 45 apps obtained, only 10 of them had been used in scientific studies.

CONCLUSIONS

There is a wide variety of commercial mobile applications of great utility and low cost, applicable in the assessment and treatment of subjects who have suffered a stroke, there is even scientific evidence, although limited, about the validity of such apps.

Effects of Adding Interferential Therapy Electro-Massage to Usual Care after Surgery in Subacromial Pain Syndrome: A Randomized Clinical Trial

Subacromial pain syndrome (SAPS) is a prevalent condition that results in loss of function. Surgery is indicated when pain and functional limitations persist after conservative measures, with scarce evidence about the most-appropriate post-operative approach. Interferential therapy (IFT), as a supplement to other interventions, has shown to relieve musculoskeletal pain. The study aim was to investigate the effects of adding IFT electro-massage to usual care after surgery in adults with SAPS. A randomized, single-blinded, controlled trial was carried out. Fifty-six adults with SAPS, who underwent acromioplasty in the previous 12 weeks, were equally distributed into an IFT electro-massage group or a control group. All participants underwent a two-week intervention (three times per week). The control group received usual care (thermotherapy, therapeutic exercise, manual therapy, and ultrasound). For participants in the IFT electro-massage group, a 15-min IFT electro-massage was added to usual care in every session. Shoulder pain intensity was assessed with a 100-mm visual analogue scale. Secondary measures included upper limb functionality (Constant-Murley score), and pain-free passive range of movement. A blinded evaluator collected outcomes at baseline and after the last treatment session. The ANOVA revealed a significant group effect, for those who received IFT electro-massage, for improvements in pain intensity, upper limb function, and shoulder flexion, abduction, internal and external rotation (all, p < 0.01). There were no between-group differences for shoulder extension (p = 0.531) and adduction (p = 0.340). Adding IFT electro-massage to usual care, including manual therapy and exercises, revealed greater positive effects on pain, upper limb function, and mobility in adults with SAPS after acromioplasty.

The Reliability of a Smartphone Goniometer Application Compared With a Traditional Goniometer for Measuring Ankle Joint Range of Motion

BACKGROUND

Evaluation of range of motion (ROM) is integral to assessment of the musculoskeletal system, is required in health fitness and pathologic conditions, and is used as an objective outcome measure. Several methods are described to check ROM, each with advantages and disadvantages. Hence, this study introduces a new device using a smartphone goniometer to measure ankle joint ROM.

OBJECTIVE

To test the reliability of smartphone goniometry in the ankle joint by comparing it with the universal goniometer (UG) and to assess interrater and intrarater reliability for the smartphone goniometer record (SGR) application.

METHODS

Fifty-eight healthy volunteers (29 men and 29 women aged 18-30 years) underwent SGR and UG measurement of ankle joint dorsiflexion and plantarflexion. Two examiners measured ankle joint ROM. Descriptive statistics were calculated for descriptive and anthropometric variables, as were intraclass correlation coefficients (ICCs).

RESULTS

There were 58 usable data sets. For measuring ankle dorsiflexion ROM, both instruments showed excellent interrater reliability: UG (ICC = 0.87) and SGR (ICC = 0.89). Intrarater reliability was excellent in both instruments in ankle dorsiflexion: UG and SGR (mean ICC = 0.91). For measuring ankle plantarflexion, both instruments showed excellent interrater reliability: UG (ICC = 0.76) and SGR (ICC = 0.82). Intrarater reliability was excellent in both instruments in ankle plantarflexion: UG (mean ICC = 0.85) and SGR (mean ICC = 0.82).

CONCLUSIONS

Smartphone-based goniometers can be used to assess active ROM of the ankle joint because they can achieve a high degree of intrarater and interrater reliability.

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.

Rater reliability and construct validity of a mobile application for posture analysis

[Purpose] Measurement of posture is important for those with a clinical diagnosis as well as researchers aiming to understand the impact of faulty postures on the development of musculoskeletal disorders. A reliable, cost-effective and low tech posture measure may be beneficial for research and clinical applications. The purpose of this study was to determine rater reliability and construct validity of a posture screening mobile application in healthy young adults. [Subjects and Methods] Pictures of subjects were taken in three standing positions. Two raters independently digitized the static standing posture image twice. The app calculated posture variables, including sagittal and coronal plane translations and angulations. Intra- and inter-rater reliability were calculated using the appropriate ICC models for complete agreement. Construct validity was determined through comparison of known groups using repeated measures ANOVA. [Results] Intra-rater reliability ranged from 0.71 to 0.99. Inter-rater reliability was good to excellent for all translations. ICCs were stronger for translations versus angulations. The construct validity analysis found that the app was able to detect the change in the four variables selected. [Conclusion] The posture mobile application has demonstrated strong rater reliability and preliminary evidence of construct validity. This application may have utility in clinical and research settings.

Reliability and concurrent validity of a new iPhone® goniometric application for measuring active wrist range of motion: a cross-sectional study in asymptomatic subjects

Measurement of wrist range of motion (ROM) is often considered to be an essential component of wrist physical examination. The measurement can be carried out through various instruments such as goniometers and inclinometers. Recent smartphones have been equipped with accelerometers and magnetometers, which, through specific software applications (apps) can be used for goniometric functions. This study, for the first time, aimed to evaluate the reliability and concurrent validity of a new smartphone goniometric app (Goniometer Pro©) for measuring active wrist ROM. In all, 120 wrists of 70 asymptomatic adults (38 men and 32 women; aged 18-40 years) were assessed in a physiotherapy clinic located at the School of Rehabilitation Sciences, Iran University of Medical Science and Health Services, Tehran, Iran. Following the recruitment process, active wrist ROM was measured using a universal goniometer and iPhone® 5 app. Two blinded examiners each utilized the universal goniometer and iPhone® to measure active wrist ROM using a volar/dorsal alignment technique in the following sequences: flexion, extension, radial deviation, and ulnar deviation. The second (2 h later) and third (48 h later) sessions were carried out in the same manner as the first session. All the measurements were conducted three times and the mean value of three repetitions for each measurement was used for analysis. Intraclass correlation coefficient (ICC) models (3, k) and (2, k) were used to determine the intra-rater and inter-rater reliability, respectively. The Pearson correlation coefficients were used to establish concurrent validity of the iPhone® app. Good to excellent intra-rater and inter-rater reliability was demonstrated for the goniometer with ICC values of ≥ 0.82 and ≥ 0.73 and the iPhone® app with ICC values of ≥ 0.83 and ≥ 0.79, respectively. Minimum detectable change at the 95% confidence level (MDC95 ) was computed as 1.96 × standard error of measurement × √2. The MDC95 ranged from 1.66° to 5.35° for the intra-rater analysis and from 1.97° to 6.15° for the inter-rater analysis. The concurrent validity between the two instruments was high, with r values of ≥ 0.80. From the results of this cross-sectional study, it can be concluded that the iPhone® app possesses good to excellent intra-rater and inter-rater reliability and concurrent validity. It seems that this app can be used for the measurement of wrist ROM. However, further research is needed to evaluate symptomatic subjects using this app.