Non-radiographic methods of measuring global sagittal balance: a systematic review

Relation between Photogrammetry and Spinal Mouse for Lumbopelvic Assessment in Adolescents with Thoracic Kyphosis

The evaluation of the lumbopelvic region is a crucial point during postural assessment in childhood and adolescence. Photogrammetry (PG) and Spinal Mouse (SM) are two of the most debated tools to properly analyze postural alignment and avoid misleading data. This study aims to find out the best linear regression model that could relate the analytic measurements of the SM with one or more PG parameters in adolescents with kyphotic postures. Thirty-nine adolescents (female = 35.9%) with structural and non-structural kyphosis were analyzed (13.2 ± 1.8 years; 1.59 ± 0.12 m; 47.6 ± 11.8 kg) using the SM and PG on the sagittal plane in a standing and forward-bending position, allowing for the measurement of body vertical inclination, lumbar and pelvic alignment, trunk flexion, sacral inclination during bending, and hip position during bending. Lordosis lumbar angles (SM) were significantly (r = -0.379, r = -0.328) correlated with the SIPS-SIAS angle (PG) during upright standing, while in the bending position, the highest correlation appeared among the sacral-hip (SM) and the sacral tangent (ST_PG; r = -0.72) angles. The stepwise backward procedure was assessed to estimate the SM variability in the bending and standing positions. Only in the bending position did the linear regression model reach high goodness-of-fit values with two regressors (ST_PG η2=0.504, BMI η2=0.252; adjusted- R2 =0.558, p < 0.001, CCC = 0.972, r = 0.763). Despite gold-standard methods reducing error evaluation, physicians and kinesiologists may consider photogrammetry as a good method for spinal curve prediction.

An investigation of the reproducibility of a self-selected natural feet position when standing: Implications for the assessment of upright standing posture

BACKGROUND

Photogrammetry is often used to evaluate standing static postural alignment. Patients are often instructed to self-select a natural feet position but it's unclear whether this position can be consistently replicated across repeated assessments.

OBJECTIVE

To determine whether people can replicate a self-selected natural feet position in upright standing across three sessions on different days.

DESIGN

Between days test-retest reliability.

SETTING

University laboratory.

METHODS

Three variables - Base of Support (BoS), Foot Width (FW), Feet Opening Angle (FOA) - were measured from foot tracings of 150 participants (18-30 years) using established procedures. BoS data were assessed for systematic bias (Analysis of Variance), and absolute (Coefficient of Variation - CV%) and relative (Intraclass Correlation Coefficient - ICC) reliability.

RESULTS

There was systematic bias in the BoS data across the three testing sessions. The CV% for the BoS data was 15.2%. The ICC (95% CI) for the BoS data was 0.84 (0.79-0.87). There were moderate-large correlations between the BoS and both FOA and FW respectively within each session.

CONCLUSION

If clinicians want to allow patients to use their self-selected natural feet position for repeated photogrammetric assessment of their static postural alignment it would be better to standardise the position of the feet, for example, by creating a tracing of a patient's self-selected natural feet position.

Do key measurement parameters derived from specific cervical vertebral segments differ between lordotic and non-lordotic cervical spine alignments? A study of asymptomatic young adults

BACKGROUND

Measurement parameters derived from specific cervical vertebral segments (e.g., C2 slope) can provide clinicians with important information on cervical sagittal balance and guide pre- and post-surgical decision-making processes. It is unclear however, what constitutes typical values for these types of measurements in an asymptomatic population of young adults, whether values change depending upon the classification of the cervical spine's global alignment, and if any non-lordotic cervical subtypes display values that are comparable to those reported for pre-surgery patients.

METHODS

Neutral lateral cervical radiographs of 150 asymptomatic participants (18-30 years) were taken. Global cervical alignment was classified as lordotic or one of four non-lordotic subtypes using a multi-method subtyping protocol. Four key measurement parameters - the anterior translation of the head measure (ATHM), C0-C2 angle, C2 slope, and C7 slope - were derived from specific cervical segments. Independent samples t-tests were used to compare lordotic and non-lordotic groups.

RESULTS

There was considerable variation in the four key measurement parameters amongst this asymptomatic population of young adults. Thirty-four percent of the sample were classified as lordotic and 66% were classified as non-lordotic. There was a significant difference (p ≤ 0.0125) between lordotic and non-lordotic groups for the C0-C2 angle, C2 slope and C7 slope. There was no difference between groups for the ATHM (p ≥ 0.0125). Within the non-lordotic group, the global-kyphotic (GK) subtype had the largest mean C2 slope, largest mean C0-C2 angle, and smallest mean C7 slope.

CONCLUSIONS

Long term prospective investigations are required to determine whether possible biomarkers (alignment parameters/radiological measurements) for spinal degenerative changes can be identified so that early interventions can be put in place to try and reduce the impact of neck pain on society.

Severity of slouched posture during smartphone use is associated with the musculoskeletal discomfort, daily usage, and school year among adolescents

Real-time measurement of the craniovertebral, thoracic kyphosis, and lumbar lordosis angles during natural and smartphone usage postures in sitting were analysed in a cohort of 560 adolescents using independent t-tests and Spearman's correlations between their reported musculoskeletal symptoms, daily device use and school year. Students with musculoskeletal symptoms (mean difference: 4.1-9.4°, p < .001) and in secondary schools (mean difference: 13.6-29.4°, p < .001) had a greater forward-head posture quantified by craniovertebral angle in both postures. Loss of lumbar lordosis was found in students spending ≥2 h/day on electronic devices (mean difference: 3.2°, p = .029) and those with musculoskeletal symptoms (mean difference: 5.4°, p = .001). Secondary school students exhibited a greater thoracic kyphosis when using smartphones (mean difference: 3.3°, p = .003). Findings suggest the urgent need for early and proactive intervention targeted to minimise the risk of developing musculoskeletal disorders related to intense device use for young adolescents.Practitioner Summary: Adolescents: (1) in higher school year had increased forward-head posture (FHP) and thoracic kyphosis; (2) with musculoskeletal symptoms had increased FHP and loss of lumbar lordosis, and; (3) with extended device use had a loss of lumbar lordosis. Early intervention targeting young adolescents promoting optimal posture and habit of device use is warranted.

Creation and Evaluation of a Severity Classification of Hyperkyphosis and Hypolordosis for Exercise Therapy

The rise in the occurrence of musculoskeletal disorders, such as thoracic hyperkyphosis (THK) or lumbar hypolordosis (LHL), is a result of demographic changes. Exercise therapy is an effective approach that can reduce related disabilities and costs. To ensure successful therapy, an individualized exercise program adapted to the severity of the disorder is expedient. Nevertheless, appropriate classification systems are scarce. This project aimed to develop and evaluate a severity classification focused on exercise therapy for patients with THK or LHL. A multilevel severity classification was developed and evaluated by means of an online survey. Reference limits of spinal shape angles were established by data from video rasterstereography of 201 healthy participants. A mean kyphosis angle of 50.03° and an average lordosis angle of 40.72° were calculated as healthy references. The strength of the multilevel classification consisting of the combination of subjective pain and objective spinal shape factors was confirmed by the survey (70% agreement). In particular, the included pain parameters were considered relevant by 78% of the experts. Even though the results of the survey provide important evidence for further analyses and optimization options of the classification system, the current version is still acceptable as therapeutic support.

Relation between Photogrammetry and Spinal Mouse for Sagittal Imbalance Assessment in Adolescents with Thoracic Kyphosis

The evaluation of postural alignment in childhood and adolescence is fundamental for sports, health, and daily life activities. Spinal Mouse (SM) and photogrammetry (PG) are two of the most debated tools in postural evaluation because choosing the proper instrument is also important to avoid false or misleading data. This research aims to find out the best linear regression models that could relate the analytic kyphosis measurements of the SM with one or more PG parameters of body posture in adolescents with kyphotic posture. Thirty-four adolescents with structural and non-structural kyphosis were analyzed (13.1 ± 1.8 years; 1.59 ± 0.13 m; 47.0 ± 12.2 kg) using SM and PG on the sagittal plane in a standing and forward-bending position, allowing us to measure body vertical inclination, trunk flexion, and sacral inclination and hip position during bending. The stepwise backward procedure was assessed to estimate the variability of the grade of inclination of the spine and thoracic spine curvature with fixed upper and lower limits, evaluated with SM during flexion. In both models, the PG angle between the horizontal line and a line connecting the sacral endplate-C7 spinous process and the PG hip position were the best regressors (adjusted-R² SM bend = 0.804, p < 0.001; adjusted-R² SM fixed bending = 0.488, p < 0.001). Several Spinal Mouse and photogrammetry parameters showed significant correlations, especially when the Spinal Mouse measurements were taken when the adolescents were in the forward-bending position. Physicians and kinesiologists may consider photogrammetry as a good method for spinal curve prediction.

Validity and Reliability of a Non-Radiographic Postural Analysis Device Based on an RGB-Depth Camera Comparing EOS 3D Imaging: A Prospective Observational Study

The posture-analyzing and virtual reconstructing device (PAViR) used a Red Green Blue-Depth camera as a sensor and skeleton reconstruction images were produced. This PAViR quickly analyzed the whole posture from multiple repetitive shots without radiation exposure in clothes and provided a virtual skeleton within seconds. This study aims to evaluate the reliability when shooting repeatedly and to assess the validity compared to parameters of full-body, low-dose X-rays (EOSs) when applied as diagnostic imaging. As a prospective and observational study, 100 patients with musculoskeletal pain underwent an EOS to obtain whole body coronal and sagittal images. The outcome measures were human posture parameters, which were divided by the standing plane in both EOSs and PAViRs as follows: (1) a coronal view (asymmetric clavicle height, pelvic oblique, bilateral Q angles of the knee, and center of seventh cervical vertebra-central sacral line (C7-CSL)) and (2) a sagittal view (forward head posture). A validation of the PAViR compared to the EOSs revealed that C7-CSL showed a moderate positive correlation with that of the EOS (r = 0.42, p < 0.01). The forward head posture (r = 0.39, p < 0.01), asymmetric clavicle height (r = 0.37, p < 0.01), and pelvic oblique (r = 0.32, p < 0.01) compared to those of the EOS had slightly positive correlations. The PAViR has excellent intra-rater reliability in people with somatic dysfunction. Except for both Q angles, the PAViR has fair-to-moderate validation when compared to EOS diagnostic imaging in the parameter representing coronal and sagittal imbalance. Although the PAViR system is not yet available in the medical field, it has the potential to become a radiation-free, accessible, and cost-effective postural analysis diagnostic tool after the EOS era.

Appraisal of the New Posture Analyzing and Virtual Reconstruction Device (PAViR) for Assessing Sagittal Posture Parameters: A Prospective Observational Study

The purpose of this study was to report the clinical validation of the posture analyzing and virtual reconstruction device (PAViR) system, focusing on the accuracy of sagittal spinal parameters, compared with the EOS imaging system. Seventy patients diagnosed with segmental and somatic dysfunction were recruited between February 2020 and November 2020. Each patient was examined using the EOS imaging system and PAViR; the sagittal parameters of human body posture [forward head posture (FHP), T1 tilt angle (T1t), knee flexion angle (KF), lumbar lordosis angle (LL), and pelvic tilt angle (PT)] were analyzed to verify the correlation between the results of the two devices. The median differences in the results of the two devices showed significant differences in FHP (T4-frontal head and T4-auditory canal), T1t, and PT. In the correlation analysis, the values of FHP (C7-auditory canal, T4-frontal head, and T4-auditory canal), T1t, and PT showed a moderate correlation between the two devices (r = 0.741, 0.795, 0.761, 0.621, and 0.692, respectively) (p < 0.001). The KF and LL was fairly correlated (r = 0.514 and 0.536, respectively) (p = 0.004, both). This study presents the potential of a novel skeletal imaging system without radiation exposure, based on a 3D red-green-blue-depth camera (PAViR), as a next-generation diagnostic tool by estimating more accurate parameters through continuous multi-data-based upgrades with artificial intelligence technology.

Correlation between the Photographic Cranial Angles and Radiographic Cervical Spine Alignment

The cranial vertical angle (CVA) and cranial rotation angle (CRA) are used in clinical settings because they can be measured on lateral photographs of the head and neck. We aimed to clarify the relationship between CVA and CRA photographic measurements and radiographic cervical spine alignment. Twenty-six healthy volunteers were recruited for this study. Lateral photographs and cervical spine radiographs were obtained in the sitting position. The CVA and CRA were measured using lateral photographs of the head and neck. The C2-7 sagittal vertical axis (SVA), cervical lordosis (C2-7), and occipito-C2 lordosis (O-C2) were measured using radiographic imaging as a standard method of evaluating cervical spine alignment. Correlations between the CVA and CRA on photographs and cervical spine alignment on radiographs were analyzed. The CVA and SVA were significantly negatively correlated (ρ = −0.51; p < 0.05). Significant positive correlations were found between CVA and C2-7 (ρ = 0.59; p < 0.01) and between CRA and O-C2 (ρ = 0.65; p < 0.01). Evaluating the CVA and CRA on photographs may be useful for ascertaining head and neck alignment in the mid-lower and upper parts of the sagittal plane.

A computer vision-based mobile tool for assessing human posture: A validation study

BACKGROUND AND OBJECTIVE

Non-invasive methods for postural assessment are tools used for tracking and monitoring the progression of postural deviations. Different computer-based methods have been used to assess human posture, including mobile applications based on images and sensors. However, such solutions still require manual identification of anatomical points. This study aims to present and validate the NLMeasurer, a mobile application for postural assessment. This application takes advantage of the PoseNet, a solution based on computer vision and machine learning used to estimate human pose and identify anatomical points. From the identified points, NLMeasurer calculates postural measures.

METHODS

Twenty participants were photographed in front view while using surface markers over anatomical landmarks. Then, the surface markers were removed, and new photos were taken. The photos were analyzed by two examiners, and six postural measurements were computed with NLMeasurer and a validated biophotogrammetry software. One-sample t-test and Bland Altman procedure were used to assess agreement between the methods, and Intraclass Correlation Coefficient (ICC) was used to assess inter- and intra-rater reliability.

RESULTS

Postural measurements calculated using the NLMeasurer were in agreement with the biophotogrammetry software. Furthermore, there was good inter- and intra-rater reliability for most photos without surface markers.

CONCLUSIONS

NLMeasurer demonstrated to be a valid tool method to assess postural measurements in the frontal view. The use of surface markers on specific anatomical landmarks (i.e., ears, iliac spines and ankles) can facilitate the digital identification of these landmarks and improve the reliability of the postural measurements performed with NLMeasurer.

Non-radiographic validity and reliability measures for assessing foot types: A systematic review

BACKGROUND

Foot type classification is well recognized in clinical practice and orthopedic literature, a universally accepted classification or standardized measures to determine foot types are lacking. The objective of this study was to identify which non-radiographic assessment methods are considered valid and/or reliable for the classification of foot types.

METHOD

A systematic database search was performed. Only cross-sectional studies that performed reliability and/or validity analysis of non-radiographic methods were included. To evaluate the risk of bias, the Critical Appraisal Tool (CAT) was used to evaluate the measurement properties of objective clinical methods.

RESULTS

Twenty-six studies were included. The results of reliability and validity, in general, demonstrated high scores, but, inconsistencies were related to the variability of the measurements, heterogeneity of the methods used to determine reliability and validity, and lack of parameters for classifying foot types, which resulted in few elements to determine which method of foot type evaluation is valid and reliable.

CONCLUSION

Given the Intraclass Correlation Coefficient and CAT results and the presence of normative values, the static measurements of the "Arch Height Index", "Foot Posture Index", and "Staheli Arch Index" can be suggested to classify foot types.

Relationships between forward head posture and lumbopelvic sagittal alignment in older adults with chronic low back pain

BACKGROUND

Abnormal posture creates abnormal stress and strain in many spinal structures which are considered predisposing factors for chronic mechanical low back pain.

PURPOSE

To examine the relationships among pain intensity, forward head posture (decreased craniovertebral angle) and lumbopelvic sagittal alignment (pelvic incidence, pelvic tilt, sacral slope, and lumbar lordosis) in chronic mechanical low back pain patients.

METHODS

A cross-section correlational study was conducted on one hundred patients. A numerical-pain-rating scale was used to determine pain intensity. Standardized standing lateral radiographs were analyzed to measure the spinopelvic angles. Reported data were analyzed using correlation coefficients, and regression analyses.

RESULTS

Lumbar lordosis had very strong positive correlations with each pain intensity and sacral slope. Pain intensity had a strong positive correlation with sacral slope. Moderate positive correlations highlighted between pelvic tilt and craniovertebral angle. Moreover, the pelvic incidence had weak positive correlations with each sacral slope and pelvic tilt. Negative correlations were strong between pelvic tilt and each of pain intensity, lumbar lordosis and sacral slope. Craniovertebral angle had moderate negative correlations with each of pain, lumbar lordosis, and sacral slope. However, the pelvic incidence had no relations with pain, craniovertebral angle lumbar lordosis. Overall, an association of demographic data and measured variables had a significant effect on the pain multi-regression equation prediction model. They accounted for 76.60% of the variation in pain.

CONCLUSION

Abnormal spinopelvic posture relates to chronic mechanical low back pain. There are significant associations among pain intensity, FHP and lumbopelvic sagittal alignment in chronic mechanical low back pain patients.

Reliability and validity of smartphone applications to measure the spinal range of motion: A systematic review

Introduction: The objective of this study is to conduct a systematic review on the reliability and validity of various smartphone applications for spinal range of motion (ROM) measurements.Methods: Eleven studies were selected following an electronic search of PubMed, CINAHAL, Medline, Embase and SPORTDiscus. Quality appraisals of selected studies were conducted using a standardized appraisal tool.Results: Most studies demonstrated a good intra- and inter-rater reliability, as well as validity in more than 50% of joint movements. At the same time, relative reliability/validity outcomes (e.g. interclass correlation co-efficient) were stronger than absolute reliability/validity outcomes (e.g. mean differences, limits of agreement). Spinal rotation movement showed less reliability and validity when compared to other spinal movements.ConclusionsːResult of the study supports the use of smartphone applications for ROM measurements of spinal joints. However, we cannot advocate the most appropriate application for spinal ROM measurement or suggest which application is superior to all others. As clinicians have multiple options in selecting applications, it is recommended they use applications that have proven reliable and valid for that particular joint. Data from this study provides clinicians with evidence-based research on smartphone devices for measuring spinal joint ROM in clinical settings.

Radiography and photogrammetry-based methods of assessing cervical spine posture in the sagittal plane: A systematic review with meta-analysis

BACKGROUND

There are numerous radiography and photogrammetry-based methods of assessing the cervical spine posture in the sagittal plane. The choice of instrument should be based on scientific parameters such as validity and reliability, thus avoiding restrictions to the applicability of the instrument.

RESEARCH QUESTION

What radiography and photogrammetry-based methods used to assess the cervical spine posture in the sagittal plane are valid and/or reliable?

METHODS

Systematic searches were conducted following Meta-analysis of Observational Studies in Epidemiology guidelines. Methodological quality was assessed according to the Brink & Louw appraisal tool.

RESULTS

Twenty-one studies were included in the qualitative analysis. Twenty different methods of calculating cervical spine posture in the sagittal plane were found. Two studies included validation measures, 16 studies assessed inter-rater reliability, and 17 studies assessed intra-rater reliability. Fourteen studies were included for the quantitative analysis. The meta-analysis shows that the cervical arrow and cervical lordosis photogrammetry-based methods present very high intra-rater reliability. In radiography, the meta-analysis also showed that the Cobb method (inferior C2 - inferior C7), Cobb method (middle C1 - inferior C7), absolute rotation angle, and Gore angle (C2-C7) present very high inter-rater reliability, and the Cobb method (inferior C2 - inferior C7) and absolute rotation angle present very high intra-rater reliability.

SIGNIFICANCE

This systematic review presents an overview of the methods used to assess cervical spine posture and the respective information on validity and reliability. This panorama facilitates the choice of method when conducting radiography or photogrammetry-based assessment of the cervical spine in the sagittal plane. In addition, it shows the need for new studies that investigate the accuracy and precision of these methods for their possible use in larger studies.

Mobile Applications for Assessing Human Posture: A Systematic Literature Review

Smartphones are increasingly incorporated with features such as sensors and high resolution cameras that empower their capabilities, enabling their use for varied activities including human posture assessments. Previous reviews have discussed methods used in postural assessment but none of them focused exclusively on mobile applications. This paper systematically reviews mobile applications proposed for analyzing human posture based on alignment of the body in the sagittal and coronal plane. The main digital libraries were searched, 26 articles published between 2010 and 2020 were selected, and 13 mobile applications were identified, classified and discussed. Results showed that the use of mobile applications to assist with posture assessment have been demonstrated to be reliable, and this can contribute to clinical practice of health professionals, especially the assessment and reassessment phases of treatments, despite some variations when compared to traditional methods. Moreover, in the case of image-based applications, we highlight the advantage that measurements can be taken with the assessor at a certain distance with respect to the patient’s position, which is an important function for assessments performed in pandemic times such as the outbreak of COVID-19.

Spinopelvic alignment predicts disc calcification, displacement, and Modic changes: Evidence of an evolutionary etiology for clinically-relevant spinal phenotypes

Lumbar disc-displacement, Modic changes (MCs), and UTE Disc Sign (UDS) on MRI are clinically relevant spinal phenotypes that can lead to sciatica/LBP. Not all degenerated discs result in disc-displacement, MCs and UDS, suggesting varied etiologies. Spinopelvic parameters have been implicated in various spinal disorders. Pelvic incidence (PI) is "fixed parameter" since skeletal maturity. No study has addressed disc-displacement, MCs and UDS in context of spinopelvic parameters. Therefore, the aim of study was to determine if spinopelvic parameters are associated and predict clinically-relevant MRI-phenotypes. One hundred and eight population-based subjects (mean age: 52.3 years) were recruited. Spondylolisthesis and scoliosis individuals were excluded. Lumbar lordosis (LL), PI, sacral slope (SS), and pelvic tilt (PT) were assessed on lateral plain radiographs. Disc degeneration was assessed and summated, and presence or not of disc-displacement and MCs were noted on T2W MRI. UDS was detected on UTE. Following exclusion criteria, 95 subjects were assessed. Disc-displacement (82.1%), MCs (52.6%), and UDS (37.9%) were associated with lower PI, SS, LL, and LL/PI index. On multivariate analyses, lower PI was significantly related to development of these MRI phenotypes (adjusted OR range:0.95-0.92; P < .05), with critical PI value of 42° or lower exhibiting fourfold increase risk of combined phenotypes (P = .020). Of UDS discs, 39.3% had adjacent MCs and 83.6% had disc-displacement. 87.5% of MC had directly adjacent UDS. The first study to note that PI may "predict" the development of disc-displacement, MCs and UDS, suggesting potential sub-variants and mechanistic susceptibility that may be grounded in spinopelvic evolution. An "evolutionary etiological pathway" of spinal phenotype development is proposed.

Decreased Vertical Trunk Inclination Angle and Pelvic Inclination as the Result of Mid-High-Heeled Footwear on Static Posture Parameters in Asymptomatic Young Adult Women

The influence of high-heel footwear on the lumbar lordosis angle, anterior pelvic tilt, and sacral tilt are inconsistently described in the literature. This study aimed to investigate the impact of medium-height heeled footwear on the static posture parameters of homogeneous young adult standing women. Heel geometry, data acquisition process, as well as data analysis and parameter extraction stage, were controlled. Seventy-six healthy young adult women with experience in wearing high-heeled shoes were enrolled. Data of fifty-three subjects were used for analysis due to exclusion criteria (scoliotic posture or missing measurement data). A custom structured light surface topography measurement system was used for posture parameters assessment. Three barefoot measurements were taken as a reference and tested for the reliability of the posture parameters. Two 30-degree wedges were used to imitate high-heel shoes to achieve a repeatable foot position. Our study confirmed the significant (p < 0.001) reduced vertical balance angle and pelvis inclination angle with large and medium-to-large effects, respectively, due to high-heel shoes. No significant differences were found in the kyphosis or lordosis angles. High-heeled shoes of medium height in young asymptomatic women can lead to a straightening effect associated with a reduced vertical balance angle and decreased pelvic inclination.

Internal and external sagittal craniovertebral alignment: A comparison between radiological and photogrammetric approaches in asymptomatic participants

BACKGROUND

Photogrammetric measures are a commonly applied, highly reliable tool for appraising craniovertebral postures during clinical assessments, rehabilitation, and research interventions.

OBJECTIVE

This study aimed to compare and contrast three external measures of postural alignment (EMPA) using photogrammetric and radiological approaches, and to discuss whether the craniovertebral angle (CVA) reflects the shape of the underlying cervical spine.

DESIGN

Cross Sectional Correlation Study.

METHOD

Young adults attended three assessment sessions (S1, S2 and S3). S1 involved a standardised photogrammetric protocol. S2 involved radiographic image acquisition. S3 followed the same protocol in S1 but excluded the self-balancing procedure. Each session's EMPA were compared through either paired or independent samples t-tests. The different radiographic cervical subtypes and their corresponding CVAs were assessed.

RESULTS

There were no significant differences in any EMPA between the two photogrammetric sessions. The CVA was the only EMPA to show a significant difference between photogrammetric (S3) and radiographic approaches. Cervical subtype variability is present throughout the full CVA range.

CONCLUSIONS

Despite the statistically significant difference in the CVA between approaches, the mean difference was small and unlikely to be clinically meaningful. Accordingly, the quantification of EMPA can be undertaken with high levels of precision and reliability using standardised photogrammetric procedures. The CVA, however, does not provide an indication of the shape of the underlying cervical spine. The distinct radiological differences in the inter-segmental orientation of each vertebral motion segment in conjunction with the differences in the overall global cervical alignment, both within and between participants, negate this possibility.

A systematic review on the validity and reliability of tape measurement method in leg length discrepancy

Background: Leg length discrepancy measurement is an essential part of musculoskeletal clinical assessment, and tape measurement is a common clinical method. This study aimed to systematically review the results of the findings of studies on validity and reliability of the tape measurement method and the quality of reporting the literature on this topic.

Methods: A search was performed in PubMed, EBSCO, Science Direct, Web of Knowledge, Scopus, Embase, and Google Scholar using selected keywords from inception to December 2017.This systematic review was based on the PRISMA guideline. After a systematic selection process, the quality of the included studies was assessed independently by 2 reviewers using the Brink and Louw Scale for quality assessment.

Results: A total of 11 studies were finally considered for this systematic review. Two studies were about the validity of (a measurement tool) studies and 4 were reliability analysis only. Validity and reliability analyses were simultaneously applied to 5 studies. Also, 9 out of 11 studies were deemed to be of high quality based on Brink and Louw Scale. Studies showed high (ICC=0.7) to very high (ICC=0.9) levels of interrater and intrarater reliability. The validity of the methods ranged from low to very high depending on subjects.

Conclusion: Tape measurement method has acceptable reliability and validity in healthy people, but it does not have acceptable validity in measuring obese people and patients with musculoskeletal disorders. Thus, using a suitable method for LLD leg length discrepancy measurement seems to be necessary for obese and individuals with leg length discrepancy.