Evaluation of the iPhone with an acrylic sleeve versus the Scoliometer for rib hump measurement in scoliosis

Repeatability and intra and interrater reproducibility of the DIPA-S eHealth© capture and analysis system for clinical assessment of scoliosis

PURPOSE

To assess the repeatability, intra and interrater reproducibility of the DIPA-S eHealth© system for capturing and measuring clinical variables of scoliosis, including frontal trunk imbalance (FTI), sagittal trunk imbalance (STI), and angle of trunk rotation (ATR).

METHODS

Patients were photographed using the DIPA-S eHealth Capture© mobile application by family members, physiotherapists, or surgeons. Three photos were taken in each position: standing in the frontal and sagittal planes and in the axial plane in forward bending position of the trunk. The photos were analyzed by three independent evaluators using the DIPA-S eHealth Analysis© software. For repeatability, each photo was analyzed twice consecutively by the three evaluators. For intrarater reproducibility, only one evaluator reanalyzed the first photo from each plane with a 5-day interval. For interrater reproducibility, the three evaluators analyzed the first photo from each plane. The intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimal detectable change (MDC) were used (p < 0.05).

RESULTS

The sample comprised 262 images (n = 30). Repeatability was excellent for all three evaluators in all three planes (ICC 0.94 to 1.00). Intrarater reproducibility was excellent in all three planes (ICC 0.88 to 0.99). Interrater analysis was excellent for the frontal and axial planes (ICC 0.98 and 0.93), respectively. However, it was weak in the sagittal plane ICC 0.32. The SEM ranged from 0.02 to 17.6 and MDC from 0.03 to 34.6.

CONCLUSION

The DIPA-S eHealth© Capture and Analysis system demonstrates reproducibility for use in the clinical assessment of scoliosis through teleconsultations.

The preliminary results of physiotherapy scoliosis-specific exercises on spine joint position sense in adolescent idiopathic scoliosis: A randomized controlled trial

BACKGROUND

It has been observed that there are difficulties in maintaining spinal harmony in the absence of proprioceptive information, which has an important role in achieving postural control in scoliosis. One of the tests used to evaluate proprioceptive mechanisms is joint position reproduction.

OBJECTIVES

The main aim of our study was to investigate the effect of physiotherapy scoliosis-specific exercise (PSSE) on spine joint reposition (JR) sense. The second aim was to determine the effects of PSSE on the angle of trunk rotation (ATR), posture, and deformity perception in adolescent idiopathic scoliosis.

METHODS

Twenty-nine patients with adolescent idiopathic scoliosis (mean age 13.79 ± 1.82 years) were randomly allocated to two groups. "Schroth" exercises were applied to the PSSE group for 8 weeks (16 sessions). The control group was placed on the waiting list. Patients' JR error (dual inclinometer), ATR (scoliometer), posture parameters (PostureScreen Mobile, Posterior Trunk Asymmetry Index, and Anterior Trunk Asymmetry Index), and deformity perception (Walter Reed Visual Assessment Scale [WRVAS]) were assessed at the first session and at the end of 8 weeks.

RESULTS

The initial demographic characteristics, Cobb (thoracal: 19.41 ± 7.03 degrees; lumbar: 20.76 ± 7.24 degrees) and ATR (thoracal: 5.86 ± 3.98 degrees; lumbar: 5.66 ± 3.33 degrees) and clinical test parameters of the groups (JR, posture parameters, and WRVAS) were similar (P > .05). According to the findings, thoracal and lumbar JR error values (P < .05), ATR (P ≤ .001), posture parameters (P ≤ .001), and WRVAS (P = .048) were significantly improved in the PSSE group. Besides, when the groups were compared, a significant difference was found in favor of PSSE except for the deformity perception (P < .05).

CONCLUSIONS

Schroth exercises have a positive contribution for improving JR sense of the spine, vertebral rotation, and posture.

Parents can reliably and accurately detect trunk asymmetry using an inclinometer smartphone app

PURPOSE

An inclinometer smartphone application has been developed to enable the measurement of the angle of trunk inclination (ATI) to detect trunk surface asymmetry. The objective was to determine the reliability and validity of the smartphone app in the hands of non-professionals.

METHODS

Three non-professional observers and one expert surgeon measured maximum ATI twice in a study involving 69 patients seen in the spine clinics to rule out scoliosis or for regular follow-up (10-18 y.o., Cobb [0°-58°]). Observers were parents not familiar with scoliosis screening nor use of an inclinometer. They received training from a 4-minute video. Intra and inter-observer reliability was determined using the generalizability theory and validity was assessed from intraclass correlation coefficients (ICC), agreement with the expert on ATI measurements using Bland-Altman analysis, and correct identification of the threshold for consultation (set to ≥6° ATI).

RESULTS

Intra-observer and inter-observer reliability coefficients were excellent ϕ = 0.92. The standard error of measurement was 1.5° (intra-observer, 2 measurements) meaning that a parent may detect a change of 4° between examinations 95% of the time. Comparison of measurements between non-professionals and the expert resulted in ICC varying from 0.82 [0.71-0.88] to 0.84 [0.74-0.90] and agreement on the decision to consult occurred in 83 to 90% of cases.

CONCLUSION

The use of a smartphone app resulted in excellent reliability, sufficiently low standard error of measurement (SEM) and good validity in the hands of non-professionals. The device and the instructional video are adequate means to allow detection and regular examination of trunk asymmetries by non-professionals.

Study on the Reliability and Accuracy of Scolioscope, a New Digital Scoliometer

Early detection of scoliosis with school screening and quick, easy, and reliable assessment of its progress are of paramount importance in the management of patients. There have been several tools described, with the most common being the analog scoliometer. Most recently, smartphone applications have entered this area with and without the use of sleeves for the device. There is no research that has evaluated the accuracy of measurements both left and right in either digital or analog devices. In this study, we evaluated the reliability and validity of a new digital scoliometer called the Scolioscope. Thirty subjects were included for the intra-rater reliability study. ICC values >0.9 were calculated both for same-day and between-day measurements. The device was highly accurate with an average difference from the ones set on the sine bar of 0.03° for right-side measurements and 0.18° for the left. These measurements suggest a highly accurate and reliable tool.

Idiopathic scoliosis and associated factors among school children: a school-based screening in Ethiopia

Background

Early detection of scoliosis is a preface to prevent progression. In resource-constrained countries like Ethiopia, there is a need for a cost-effective reliable solution for screening. The surprising fact is that there is neither idiopathic scoliosis screening nor reporting of data from Ethiopia. This study aimed to identify the magnitude, associated factors of scoliosis among school children by using non-invasive and less expensive scoliometer Smartphone app and Adams forward bending test.

Methods

A school-based cross-sectional survey was carried out from March to June 2019 at seven primary schools. Children were screened by using physical examination (Adams forward bend test) and scoligauge iPhone app. Univariate and multivariable binary logistic regression model analysis was used to identify factors associated with idiopathic scoliosis.

Results

A total of 1905 children aged between 5 and 16 years were screened, 3.3 % (95 % CI 2.5–4.1) of them were found positive using the scoligauge HD and among them only 1.8 % were identified positive for Adam’s forward bend test. The associated factors of idiopathic scoliosis identified by multivariate analysis were; spinal pain (AOR 4.1, 95 % CI 2.42, 6.89), student sitting on stool: (AOR, 7.03; 95 % CI, 1.52, 32.5), sitting on the bench with a backrest (AOR 4.12; 95 %CI, 1.12, 15.14) and sitting on the bench without backrest: (AOR 4.56; 95 % CI 1.20, 17.34).

Conclusions

The magnitude of idiopathic scoliosis was relatively low in study setup. More attention is needed towards sitting furniture designs and for children reporting spinal pain.There is a reasonable level of recommendation to advocate that large school-based scoliosis screening was able to detect scoliosis among school children.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13690-021-00633-0.

The smartphone as a tool to screen for scoliosis, applicable by everyone

PURPOSE (MAIN PURPOSES AND RESEARCH QUESTION)

The purpose of this study is to assess the accuracy and precision of the smartphone with application and casing (Scolioscreen) compared to the Scoliometer.

METHODS

The Axial Trunk Rotation (ATR) was measured in adolescent scoliosis patients visiting the outpatient clinic while performing the Adam Forward Bending Test. The Scolioscreen measurements were performed by the orthopedic surgeon and a parent. They were compared to the measurement with the Scoliometer by the orthopedic surgeon, the gold standard. The accuracy was determined with the Pearson's correlation coefficient, and precision was determined by assessing the intra- and inter-variability with the intra-class correlation coefficient (ICC).

RESULTS

Fifty patients with adolescent idiopathic scoliosis (44 girls) were included with a mean age of 14.1 years and a mean Cobb angle of 38.5°. The accuracy of both the parents and orthopedic surgeon was excellent with a Pearson correlation coefficient of 0.92 and 0.97, respectively. All the ICC's, both intra- and inter-observer, were over 0.92 demonstrating excellent precision.

CONCLUSION

This study confirms the accuracy and precision of the Scolioscreen when measuring the ATR on patients with AIS. Therefore, the Scoliometer can be replaced by the more easily available Scolioscreen which can be used by both physician and parents.

Reliability of a New Smartphone Accessory for Scoliosis Measurements

BACKGROUND: Idiopathic scoliosis is the most common pathology of the children’s spine, identified as spine lateral curvature with Cobb angle greater than 10°. The rapid development of technology allows, even mobile devices, to perform a quick and cheap diagnosis ensuring an accuracy similar to the Bunnell scoliometer.

OBJECTIVE: The study aimed to validate the accuracy of a newly developed accessory for measuring the angle of trunk rotation (ATR) using mobile devices.

METHODS: ATR measurements were carried out on a group of 30 adults using 3 diagnostic tools: the Bunnell scoliometer, Scolioscreen, and mScolio designed by the authors. Scolioscreen and mScolio were used together with a smartphone and the Clinometer app. Three measurements were performed using each of the methods.

RESULTS: The greatest data discrepancy was obtained between the Bunnell scoliometer and Scolioscreen (-3.7°÷4.4°) and was twice larger than between the Bunnell scoliometer and mScolio (-1.8°÷2.1°). The excellent agreement was obtained for the mScolio device, where the concordance correlation coefficient was 0.9381 (95% CI of 0.9076÷0.9588) and the interclass correlation coefficient was 0.9501 (95% CI of 0.9242÷0.9671).

CONCLUSIONS: Tests showed excellent reliability and validity of ATR using the mScolio solution. Obtained results show excellent consistency between mScolio and the Brunnell scoliometer measurements.

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.

Evaluation of a new apparatus combining a mobile device and hand-held roller for the detection of spinal deformities: association with the sum of the right and left angles of trunk inclination

PURPOSE

To investigate the intra- and inter-observer reliabilities of the newly developed i-Scolioroller for scoliosis screening, and to determine the optimal i-Scolioroller measurement cutoff values for identifying adolescent scoliosis with a Cobb angle ≥ 20°.

METHODS

The i-Scolioroller displays the right- and left-side maximum inclination angle (Rmax, Lmax) during the forward bending test (FBT), as well as the angle of trunk inclination (ATI, i.e., whether the Rmax or Lmax is greater). Sum-ATI is defined as the sum of Rmax and Lmax. Intra-class correlation coefficients (ICC) of the ATI and sum-ATI measurements were calculated to analyze the intra- and inter-observer reliabilities for 10 plaster torsos in FBT positions obtained from patients with idiopathic scoliosis. The optimal cutoff values for scoliosis were determined using receiver operating characteristic (ROC) analysis of i-Scolioroller measurements versus Cobb angles obtained from the upright whole-spine radiographs of 112 adolescent outpatients.

RESULTS

The intra-observer ICCs for the ATI/sum-ATI for 3 observers were 0.851/0.856, 0.786/0.900, and 0.772/0.796, respectively, while the corresponding inter-observer ICCs for all participants were 0.733/0.745. On ROC analysis, an ATI of 8° was the optimal cutoff value for scoliosis (sensitivity and specificity: 79.2% and 70.0%, respectively). The optimal cutoff value for sum-ATI was 11° (sensitivity and specificity: 86.1% and 82.5%, respectively). The areas under the ROC curves were 0.859 for ATI and 0.908 for sum-ATI.

CONCLUSION

The optimal cutoff values for identifying scoliosis using the i-Scolioroller were a combination of 11° for the sum-ATI and 8° for the ATI.

Validation of the Measurement of the Angle of Trunk Rotation in Photogrammetry

OBJECTIVE

The purpose of this study was to validate the photogrammetric measurement of the angle of trunk rotation in relation to the scoliometer instrument.

METHODS

Fifty-eight prominences from individuals with ages between 7 and 18 and with suspicion of spinal asymmetry (SA) were evaluated through the scoliometer and photogrammetry. The photographs were analyzed in the Digital Image-based Postural Assessment software. For statistical purposes, we used Pearson's correlation test (r), root mean square error, Bland-Altman graphical analysis, and receiver operating characteristic curve. The level of significance was P ≤ .05.

RESULTS

Excellent correlation for the angle of trunk rotation was obtained between the scoliometer and photogrammetry, with a root mean square error of 3°. The Bland-Altman graphical analysis showed equally dispersed data with no participants outside the limits of agreement. The receiver operating characteristic curve evidenced that (1) the cutoff point for the identification of the presence of spinal asymmetry is 4°; (2) mild to moderate SA is between 4° and 7°; (3) moderate to severe SA is above 8°; and (4) sensitivity and specificity were above 83% and 78%, respectively, with an area under the curve ≥ 90%.

CONCLUSION

Photogrammetry is validated for measuring the angle of trunk rotation, being an accurate and accessible tool for the evaluation of patients with spinal asymmetries.

Radiation in Spine Deformity: State-of-the-Art Reviews

STUDY DESIGN/METHODS

Review article.

OBJECTIVES

This article will provide an overview regarding measurement of radiation exposure and effects on patients with spinal deformity.

SUMMARY OF BACKGROUND DATA/RESULTS

Pediatric and adult spinal deformity patients are frequently exposed to diagnostic studies exposing them to ionizing radiation. There is a concern that medical radiation can result in increased cancer risk, particularly in children who will live for a long period of time in which cancer may develop and who have rapidly dividing cells that may be more susceptible to DNA damage. CT imaging imparts 10-100 times higher radiation dosing than standard radiographs. Usage of CT imaging studies is growing in the United States and represents 50% of medical imaging exposure. In addition to the 3 millisieverts (mSv) mean natural background exposure, in the United States, the average American experiences an additional 3 mSv of exposure primarily due to medical diagnostic imaging. Early-onset scoliosis patients are at risk of high cumulative radiation exposure given the young age at diagnosis and frequency of multiorgan system involvement in the case of neuromuscular, congenital, and syndromic patients. Biplanar slot scanning reduces patient radiation exposure, and overall levels of exposure from radiographic imaging is quite low compared with CT imaging or historic radiographs. Specialized pediatric CT dosing protocols result in lower patient absorbed dose. Surgeon and team intraoperative exposure to radiation should always be a concern. Appropriate shielding with a lead apron and minimizing radiation exposure are appropriate strategies.

CONCLUSIONS

This article will help guide surgeons to make appropriate decisions regarding the need for imaging studies and advocate for low-dose imaging protocols within their facilities.

LEVEL OF EVIDENCE

V.

Quantifying Anterior Chest Wall Deformity in Adolescent Idiopathic Scoliosis: Correlation With Other Deformity Measures and Effects of Anterior Thoracoscopic Scoliosis Surgery

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

This study investigated how anterior chest wall deformity is affected by thoracoscopic anterior scoliosis fusion (TASF) surgery in adolescent idiopathic scoliosis patients. We aimed to determine correlations pre- and postoperatively with other clinical and radiological scoliosis measures.

BACKGROUND DATA

Scoliosis surgery aims to halt progression of the deformity, and to reduce its severity. Currently, deformity correction is clinically measured in terms of Cobb angle and rib hump (RH); however, a significant cosmetic concern for patients is anterior chest wall deformity.

METHODS

Pre- and postoperative CT scans of 28 female, Lenke type 1 patients with a mean preoperative Cobb angle of 50.2° ± 7.1° were retrieved from the Research Group's surgical database. Using ImageJ, 3D reconstructions of the thorax were created. Two observers measured the anterior chest wall deformity as a chest wall angle (CWA) and posterior deformity as a posterior apical deformity angle (PDA). We investigated pre- to postoperative changes in CWA, PDA, RH, and Cobb angle as well as their interrelationship.

RESULTS

All deformity parameters (Cobb angle, RH, CWA, and PDA) showed statistically significant improvement post TASF. Correlation was found between RH and Cobb angle pre- and postoperatively, Cobb angle and CWA preoperatively and between postoperative change in Cobb angle and CWA. No relationship was found between CWA and RH or PDA.

CONCLUSIONS

Anterior chest wall deformity is independent from the posterior chest wall measures RH and PDA, indicating that the anterior chest wall deformity is not reflected in the posterior rib cage. The correlation between Cobb angle and CWA indicates that the deformity in the spine and the deformity in the ribs are related, and shows that the anterior chest wall deformity is improved post thoracoscopic anterior scoliosis fusion surgery as the lateral deviation of the spine is corrected.

LEVEL OF EVIDENCE

Level III.

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.

Accuracy of 3D surface scanners for clinical torso and spinal deformity assessment

Externally visible deformities are cosmetic features of great concern for Adolescent Idiopathic Scoliosis (AIS) patients. Current assessment techniques for AIS do not fully encompass the external deformity. A non-invasive method capable of capturing superficial anatomy, such as 3D scanning, would enable better qualitative and quantitative evaluation of cosmesis. This study aimed to quantify the accuracy of commonly available scanners, in assessing posterior asymmetry in AIS. The technique of 3D surface deviation analysis was proposed as a suitable method for comparing the models created by each scanner. Eight plaster cast moulds manufactured to create braces for AIS patients were used as test samples. Four 3D scanners were selected: Solutionix RexScan CS+; Artec Eva; Microsoft Kinect V1; iPhone with 123D Catch App. These scanners were selected from those available as representative of a range of scanning technologies. Each cast was scanned and 3D models created. A simulated rib hump measurement was obtained and the surface-to-surface deviations between the Solutionix scan and all other scans were determined. The Solutionix scanner is a metrology scanner of very high quality and so it was selected as the reference. Surface-to-surface deviations were calculated in the positive and negative directions separately to specifically identify size and volume inaccuracies created by the scans. Surface deviations showed excellent agreement between the Solutionix and the Eva with deviations of +0.17 ± 0.17 mm (Eva regions larger) and -0.20 ± 0.32 mm (Eva regions smaller) (mean±SD). The Kinect showed lower agreement (+1.58 ± 1.50 mm and -0.58 ± 0.58 mm). The iPhone scans were not able to be scaled to the correct size, so were excluded. Rib hump measurements with all scanners were within clinical measurement variability (±4.9 deg) of the known values. These commercially available 3D scanners are capable of imaging torso shape in 3D and deriving clinically relevant external deformity measures. The non-invasive 3D topographic information provided can be used to improve assessment of torso shape in spinal deformity patients.

Shoulder Complex Mechanics in Adolescent Idiopathic Scoliosis and Their Relation to Patient-perceived Function

BACKGROUND

Proper contribution of the scapulothoracic joint is necessary for adequate shoulder complex function. Associations between trunk shape and abnormal scapular kinematics and subsequent shoulder dysfunction have been established; however, the extent of shoulder dysfunction in adolescent idiopathic scoliosis (AIS) is still poorly understood. The purpose of this study was to perform a comprehensive analysis of scapular kinematics during multiplanar arm motion in patients with AIS and compare kinematics and patient-reported function with that of a typically developing cohort.

METHODS

Typically developing adolescents (n=33) and patients with AIS (n=26) with no history of spine or shoulder surgery were recruited for this study. A 3-dimensional optoelectronic motion capture system was used to analyze scapular kinematics in 4 positions: rest, full abduction, forward reach, and hand to spine. Subjects in each group also completed the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire as a measure of patient-reported function.

RESULTS

The convex shoulders of the patients with AIS exhibited deficits in scapular upward rotation and posterior tilt in all positions and reduced protraction range of motion during reaching. The AIS group also reported worse patient-perceived shoulder function than the typically developing group; however, this dysfunction was not related to specific scapular kinematic patterns.

CONCLUSIONS

Patients with AIS show alterations in scapular kinematics that are associated with shoulder pathology. Despite displaying an unaffected ability to place the hand in space, the underlying joint mechanics place these adolescents at risk for future pathology. Accordingly, consideration of scapulothoracic and glenohumeral joint function is warranted in the treatment of AIS.

LEVEL OF EVIDENCE

Level III-cross-sectional comparison.

Two-dimensional digital photography for child body posture evaluation: standardized technique, reliable parameters and normative data for age 7-10 years

BACKGROUND

Digital photogrammetry provides measurements of body angles or distances which allow for quantitative posture assessment with or without the use of external markers. It is becoming an increasingly popular tool for the assessment of the musculoskeletal system. The aim of this paper is to present a structured method for the analysis of posture and its changes using a standardized digital photography technique.

MATERIAL AND METHODS

The purpose of the study was twofold. The first one comprised 91 children (44 girls and 47 boys) aged 7-10 (8.2 ± 1.0), i.e., students of primary school, and its aim was to develop the photographic method, choose the quantitative parameters, and determine the intraobserver reliability (repeatability) along with the interobserver reliability (reproducibility) measurements in sagittal plane using digital photography, as well as to compare the Rippstein plurimeter and digital photography measurements. The second one involved 7782 children (3804 girls, 3978 boys) aged 7-10 (8.4 ± 0.5), who underwent digital photography postural screening. The methods consisted in measuring and calculating selected parameters, establishing the normal ranges of photographic parameters, presenting percentile charts, as well as noticing common pitfalls and possible sources of errors in digital photography.

RESULTS

A standardized procedure for the photographic evaluation of child body posture was presented. The photographic measurements revealed very good intra- and inter-rater reliability regarding the five sagittal parameters and good reliability performed against Rippstein plurimeter measurements. The parameters displayed insignificant variability over time. Normative data were calculated based on photographic assessment, while the percentile charts were provided to serve as reference values. The technical errors observed during photogrammetry are carefully discussed in this article.

CONCLUSIONS

Technical developments are allowed for the regular use of digital photogrammetry in body posture assessment. Specific child positioning (described above) enables us to avoid incidentally modified posture. Image registration is simple, quick, harmless, and cost-effective. The semi-automatic image analysis, together with the normal values and percentile charts, makes the technique reliable in terms of child's posture documentation and corrective therapy effects' monitoring.

Is vertebral rotation correction maintained after thoracoscopic anterior scoliosis surgery? A low-dose computed tomography study

Background

Axial vertebral rotation is a key characteristic of adolescent idiopathic scoliosis (AIS), and its reduction is one of the goals of corrective surgery. Recurrence of deformity after surgical correction may relate to rotation changes that occur in the anterior vertebral column after surgery, but whether any change occurs within the fused segment or in adjacent unfused levels following thoracoscopic anterior spinal fusion (TASF) is unknown. An analysis of measurements from an existing postoperative CT dataset was performed to investigate the occurrence of inter- and intra-vertebral rotation changes after TASF within and adjacent to the fused spinal segment and look for any relationships with the Cobb angle and rib hump in the two years after surgery.

Methods

39 Lenke Type 1 main thoracic patients underwent TASF for progressive AIS and low dose computed tomography scanning of the instrumented levels of the spine at 6 and 24 months after surgery. Vertebral rotation was measured at the superior and inferior endplates on true axial images for all vertebral levels in the fused segment plus one adjacent level cranially and caudally. Intra-observer variability for rotation measurements was assessed using 95% limits of agreement to detect significant changes in inter/intra-vertebral rotation.

Results

Significant local changes in inter- and intra-vertebral rotation were found to have occurred between 6 and 24 months after anterior surgical fusion within the fused spinal segment, albeit with no consistent pattern of location or direction within the instrumented fusion construct. No significant en-bloc movement of the entire fused spinal segment relative to the adjacent un-instrumented cranial and caudal intervertebral levels was found. No clear correlation was found between any vertebral rotation changes and Cobb angle or rib hump measures.

Conclusions

Localised inter- and intra-vertebral rotation occurs between 6 and 24 months after TASF, both within the instrumented spinal segments and in the adjacent un-instrumented levels of the adolescent spine. The lack of measurable en-bloc movement of the fused segment relative to the adjacent un-instrumented levels suggests that overall stability of the instrumented construct is achieved, however the vertebrae within the fusion mass continue to adapt and remodel, resulting in ongoing local anatomical and biomechanical changes in the adolescent spine.

"Is There An App For That?" Orthopaedic Patient Preferences For A Smartphone Application

BACKGROUND

Patients are seeking out medical information on the Internet and utilizing smartphone health applications ("apps"). Smartphone use has exponentially increased among orthopaedic surgeons and patients. Despite this increase, patients are rarely directed to specific apps by physicians. No study exists querying patient preferences for a patient-centered, orthopaedic smartphone application.

OBJECTIVES

The purpose of this study is to 1) determine Internet use patterns amongst orthopaedic patients; 2) ascertain access to and use of smartphones; and 3) elucidate what features orthopaedic patients find most important in a smartphone application.

METHODS

We surveyed patients in an orthopaedic practice in an urban academic center to assess demographics, access to and patterns of Internet and Smartphone use, and preferences for features in a smartphone app.

RESULTS

A total of 310 surveys were completed. Eighty percent of patients reported Internet access, and 62% used the Internet for health information. Seventy-seven percent owned smartphones, 45% used them for health information, and 28% owned health apps. Only 11% were referred to an app by a physician. The highest ranked features were appointment reminders, ability to view test results, communication with physicians, and discharge instructions. General orthopaedic information and pictures or videos explaining surgery were the 2 lowest ranked features. Seventy-one percent of patients felt an app with some of the described features would improve their healthcare experiences, and 40% would pay for the app.

CONCLUSIONS

The smartphone is an under-utilized tool to enhance patient-physician communication, increase satisfaction, and improve quality of care. Patients were enthusiastic about app features that are often included in patient health portals, but ranked orthopaedic educational features lowest. Further study is required to elucidate how best to use orthopaedic apps as physician-directed educational opportunities to promote patient satisfaction and quality of care.

Intraoperative Correction of Femoral Rotational Deformity Using a Conventional Navigation System and a Smartphone: A Novel Technique

The intraoperatively rotational control of femoral shaft fractures treated with a closed intramedullary interlocking nailing is a challenging problem. A novel surgical technique that includes respective insertions of guidewires into the proximal and distal femur under the guidance of a 2-dimensional fluoroscopy-based navigation system and the measurements of the intersection angle subtended by the proximal and distal guidewires with the smartphone positional software has been designed to provide intraoperatively quantitative parameters of femoral rotation deformation. The comparison of these parameters with preoperative measurement values of the contralateral intact femur on computed tomography images was used to align the proximal and distal femur fragments based on periaxial rotation. The purpose of this study was to evaluate its clinical suitability. Ten adult patients with femoral shaft fractures were attempted to correct intraoperatively femoral rotational deformity using this novel technique. The additional operation time was 20.04 ± 3.27 minutes. The angle of femoral anteversion was 20.85° ± 4.22°, 38.14° ± 19.07°, and 22.77° ± 3.38° in the contralateral intact and preoperatively and postoperatively injured femur, respectively. The mean absolute difference between both limbs was preoperatively 21.55° ± 10.14° with a statistically significant difference ( P = .005) and postoperatively 3.24° ± 1.69° with no statistically significant difference ( P = .092). Our results showed this novel technique could become an effective tool to correct intraoperatively rotational malalignment of femoral fractures.

Evaluating the Change in Axial Vertebral Rotation Following Thoracoscopic Anterior Scoliosis Surgery Using Low-Dose Computed Tomography

BACKGROUND CONTEXT

In recent years, there has been increasing appreciation of the need to treat scoliosis as a three-dimensional deformity.

PURPOSE

Assessment of surgical strategies and outcomes should consider not only the coronal plane correction but also derotation of the transverse plane deformity that can affect trunk appearance.

STUDY DESIGN

This study included a cohort of 29 female adolescent idiopathic scoliosis patients who received thoracoscopic single rod anterior fusion (TASF) surgery. This study used pre- and postoperative low-dose computed tomographic (CT) scans to accurately measure apical axial vertebral rotation (AVR).

METHODS

The pre- and postoperative values for clinically measured coronal Cobb correction and rib hump correction as well as AVR were compared to determine whether these values improved postoperatively. There are no conflicts of interest to report for authors of this investigation.

RESULTS

As expected, statistically significant reductions in coronal Cobb angle (mean preoperative Cobb 51°, reducing to 24° at the two-year follow-up) and rib hump (mean preoperative rib hump 15°, reducing to 7° at two-year follow-up) were achieved. The mean reduction in apical AVR measured using CT was only 3° (mean preoperative AVR 16°, reducing to 13° at two-year follow-up), which was statistically but not clinically significant. Significant correlations were found between Cobb angle and rib hump, between Cobb angle and AVR, and between AVR and rib hump, suggesting that patients with greater coronal Cobb correction also achieve better derotation with this surgical procedure.

CONCLUSIONS

The historical low-dose CT data set permitted detailed three-dimensional assessment of the deformity correction that is achieved using thoracoscopic anterior spinal fusion for progressive adolescent idiopathic scoliosis.

Mobile Device Trends in Orthopedic Surgery: Rapid Change and Future Implications

Mobile devices are increasingly becoming integral communication and clinical tools. Monitoring the prevalence and utilization characteristics of surgeons and trainees is critical to understanding how these new technologies can be best used in practice. The authors conducted a prospective Internet-based survey over 7 time points from August 2010 to August 2014 at all nationwide American Council for Graduate Medical Education-accredited orthopedic programs. The survey questionnaire was designed to evaluate the use of devices and mobile applications (apps) among trainees and physicians in the clinical setting. Results were analyzed and summarized for orthopedic surgeons and trainees. During the 48-month period, there were 7 time points with 467, 622, 329, 223, 237, 111, and 134 responses. Mobile device use in the clinical setting increased across all fields and levels of training during the study period. Orthopedic trainees increased their use of Smartphone apps in the clinical setting from 60% to 84%, whereas attending use increased from 41% to 61%. During this time frame, use of Apple/Android platforms increased from 45%/13% to 85%/15%, respectively. At all time points, 70% of orthopedic surgeons believed their institution/hospital should support mobile device use. As measured over a 48-month period, mobile devices have become an ubiquitous tool in the clinical setting among orthopedic surgeons and trainees. The authors expect these trends to continue and encourage providers and trainees to be aware of the limitations and risks inherent with new technology.

Pathways of healthcare utilisation in patients with suspected adolescent idiopathic scoliosis: a cross-sectional study

Background

School screening programs for adolescent idiopathic scoliosis (AIS) have been discontinued in Canada and elsewhere because they were not considered cost-effective. In communities lacking such programs, we expect a significant variety of healthcare pathways and timeframes for patient referrals to orthopaedics.

The objectives of this study were: 1) to characterise the healthcare pathways of young children with suspected AIS in a population without school screening; and 2) to investigate the relationships between these healthcare pathways and the appropriateness of referrals to specialised orthopaedic clinics.

Methods

This study concerned all children, ages 10 to 18, referred for an initial visit for suspected AIS to any of the five out-patient paediatric orthopaedic clinics of south-western Quebec (Canada). For the 831 participants, referrals to orthopaedics were characterised as appropriate, late, or inappropriate, based on known risk factors for AIS progression and on treatment indications. Parents documented the circumstances of healthcare use prior to the orthopaedic consultation. Relevant predisposing, enabling, and need variables derived from Andersen’s Behavioral Model of Health Services Use were also documented. Healthcare pathways were characterised by developing a taxonomy using multiple correspondence analysis prior to hierarchical classification. Associations between the healthcare pathways and appropriateness of referral were assessed using multinomial regression analyses.

Results

We constructed a taxonomy of five distinct healthcare pathways: 1) Lay/regular source of care interrelation, 2) Other professionals, 3) Lay/consultation discontinuity, 4) Other medical doctor, and 5) Regular source of care continuity. Laypersons played an important role in AIS suspicion (53 % of cases), but did not prevent late referrals. Continuity of care, as opposed to numerous uncoordinated consultations, was an effective strategy to prevent late referrals (OR = 0.32 [0.17–0.59]), but was related to increased probability of inappropriate referrals.

Conclusions

We identified two cardinal characteristics that distinguished the healthcare pathways and related significantly to appropriateness of referral status, namely the role of laypersons and the involvement of the regular source of care. This suggests directions for intervention such as advocating for access to a regular source of care, increasing awareness of the disease to medical practitioners’ and improving their knowledge of AIS detection and referral criteria.

Mobile Phone-Based Joint Angle Measurement for Functional Assessment and Rehabilitation of Proprioception

Assessment of joint functional and proprioceptive abilities is essential for balance, posture, and motor control rehabilitation. Joint functional ability refers to the capacity of movement of the joint. It may be evaluated thereby measuring the joint range of motion (ROM). Proprioception can be defined as the perception of the position and of the movement of various body parts in space. Its role is essential in sensorimotor control for movement acuity, joint stability, coordination, and balance. Its clinical evaluation is commonly based on the assessment of the joint position sense (JPS). Both ROM and JPS measurements require estimating angles through goniometer, scoliometer, laser-pointer, and bubble or digital inclinometer. With the arrival of Smartphones, these costly clinical tools tend to be replaced. Beyond evaluation, maintaining and/or improving joint functional and proprioceptive abilities by training with physical therapy is important for long-term management. This review aims to report Smartphone applications used for measuring and improving functional and proprioceptive abilities. It identifies that Smartphone applications are reliable for clinical measurements and are mainly used to assess ROM and JPS. However, there is lack of studies on Smartphone applications which can be used in an autonomous way to provide physical therapy exercises at home.

Reliability and validity of inexpensive and easily administered anthropometric clinical evaluation methods of postural asymmetry measurement in adolescent idiopathic scoliosis: a systematic review

PURPOSE

As accurate and reproducible measurements of spinal curvature are crucial in the examination of patients with adolescent idiopathic scoliosis (AIS), this systematic review aims to report on the reliability and validity of a range of inexpensive and easily administered anthropometric methods of postural asymmetry measurement in an AIS population, to inform practice in a clinical setting.

METHODS

A systematic search of health research databases located studies assessing reliability and validity of inexpensive and easily administered anthropometric measures.

RESULTS

Fourteen studies satisfied eligibility criteria. The methodological quality of included studies ranged from low to high. Validity studies were of moderate to high quality. In total, nine clinically applicable, inexpensive and easily administered anthropometric methods were identified, for assessing AIS curvature. All methods demonstrated high to very high inter-observer and intra-observer reliability. Reported criterion validity of the scoliometer and 2D photographs, when compared to Cobb angle assessed from radiographs, ranged from low to very high. iPhone measurements correlated well with scoliometer measurements. 2D photography results had a moderate to high correlation with 3D topography results.

CONCLUSIONS

Overall, strong levels of evidence exist for iPhone and scoliometer measurements, with a high to very high reliability and moderate to very high validity. Moderate levels of evidence exist for scoliometer with mathematical formula and clinical examination with moderate and low validity, respectively. Limited evidence exists for aesthetic tools TRACE and AI and 2D photography. These results indicate there are accurate and reproducible anthropometric measures that are inexpensive and applicable in therapy settings to assess postural asymmetry; however, these only exist for measurement in the transverse plane, despite 3D characteristics of AIS. Further research is required into an inexpensive and easily administered method that can assess postural asymmetry in all anatomical planes.

Smartphone apps for spinal surgery: is technology good or evil?

PURPOSE

The increased utilization of smartphones together with their downloadable applications (apps) provides opportunity for doctors, including spinal surgeons, to integrate such technology into clinical practice. However, the clinical reliability of the medical app sector remains questionable. We reviewed available apps themed specifically towards spinal surgery and related conditions and assessed the level of medical professional involvement in their design and content.

METHOD

The most popular smartphone app stores (Android, Apple, Blackberry, Windows, Samsung, Nokia) were searched for spinal surgery-themed apps, using the disease terms Spinal Surgery, Back Surgery, Spine, Disc Prolapse, Sciatica, Radiculopathy, Spinal Stenosis, Scoliosis, Spinal Fracture and Spondylolisthesis.

RESULTS

A total of 78 individual spinal surgery themed apps were identified, of which there were six duplicates (N = 72). According to app store classifications, there were 57 (79 %) medical themed apps, 11 (15 %) health and fitness themed apps, 1 (1 %) business and 3 (4 %) education themed apps. Forty-five (63 %) apps were available for download free of charge. For those that charged access, the prices ranged from £0.62 to £47.99. Only 44 % of spinal surgery apps had customer satisfaction ratings and 56 % had named medical professional involvement in their development or content.

CONCLUSIONS

This is the first study to specifically address the characteristics of apps related to spinal surgery. We found that nearly half of spinal surgery apps had no named medical professional involvement, raising concerns over app content and evidence base for their use. We recommend increased regulation of spinal surgical apps to improve the accountability of app content.

Sensitivity of fNIRS measurement to head motion: an applied use of smartphones in the lab

BACKGROUND

Powerful computing capabilities in small, easy to use hand-held devices have made smart technologies such as smartphones and tablets ubiquitous in today's society. The capabilities of these devices provide scientists with many tools that can be used to improve the scientific method.

METHOD

Here, we demonstrate how smartphones may be used to quantify the sensitivity of functional near-infrared spectroscopy (fNIRS) signal to head motion. By attaching a smartphone to participants' heads during the fNIRS scan, we were able to capture data describing the degree of head motion.

RESULTS

Our results demonstrate that data recorded from an off-the-shelf smartphone accelerometer may be used to identify correlations between head-movement and fNIRS signal change. Furthermore, our results identify correlations between the magnitudes of head-movement and signal artifact, as well as a relationship between the direction of head movement and the location of the resulting signal noise.

CONCLUSIONS

These data provide a valuable proof-of-concept for the use of off-the-shelf smart technologies in neuroimaging applications.

Validity and reliability of the iPhone to measure rib hump in scoliosis

STUDY DESIGN

This was a prospective blinded validity and reliability analysis.

OBJECTIVE

The aim of this study was validation and reliability evaluation of the Scoligauge iPhone app.

BACKGROUND

The scoliometer is used to clinically measure the rib hump in scoliosis as a means to evaluate the axial trunk rotation. The increasing availability of smartphone with built-in accelerometer led to the development of a vast number of applications to measure angles. Of these, the Scoligauge mimics a scoliometer. The aim of this study was to compare the validity of the Scoligauge iPhone application without an associated adapter with the traditional scoliometer and to test the reliability of the application in a clinical setting.

METHODS

Two observers measured the rib hump deformity on 34 consecutive patients with idiopathic scoliosis with an average Cobb angle of 24.2 ± 13.5 degrees (range, 4 to 65 degrees). Measurements were made with an iPhone without the adapter and with a scoliometer. The validity as well as the interobserver and intraobserver reliability were calculated using the intraclass coefficient (ICC) and the Bland-Altman test.

RESULTS

The mean difference between the scoliometer and the Scoligauge application was 0.4 degrees [95% confidence interval (CI) of ± 3.1 degrees] with an ICC of 0.947 (P < 0.001). The intraobserver and interobserver ICC were 0.961 (P < 0.001) and 0.901 (P < 0.001), respectively. The mean intraobserver difference was 0.0 degrees (95% CI of ± 2.7 degrees) and the mean interobserver difference was 0.1 degrees (95% CI of ± 4.4 degrees).

CONCLUSIONS

The intraobserver and interobserver reliability of the Scoligauge iPhone app, as well as its validity compared with the scoliometer, are excellent. The mean differences between measurements are small and clinically not significant. Thus, the Scoligauge application is valid for clinical evaluation even without special adapter.

LEVEL OF EVIDENCE

Level I (Diagnostic Study).

Evaluation of an apparatus to be combined with a smartphone for the early detection of spinal deformities

BACKGROUND

Mobile smartphones are equipped with inclinometers enabling them to acquire angular clinical measures. The Scolioscreen has been developed in conjunction with a smartphone APP to enable the measure of the angle of trunk inclination (ATI) thus offering a convenient and reliable means to measure and screen for spinal deformities. The objective was to compare the reliability and accuracy of a Scolioscreen-smartphone combination, a smartphone alone, and a Scoliometer, for measuring the angle of trunk inclination in spinal deformities under blinded conditions for intra- and inter-observer analyses.

METHODS

A cohort of 39 patients with adolescent idiopathic scoliosis were recruited. Each had maximum ATI measured by 3 observers: attending spine surgeon, nurse, and parent presenting with patient. Two series of measurements were performed by each observer using Scolioscreen-smartphone, smartphone alone and Scoliometer. Intra-class correlation coefficients (ICC) from two-way mixed model based on absolute agreement were used to assess intra- and inter-observer reliability as well as consistency between measurement techniques.

RESULTS

Intra- and inter-observer reliability for measuring maximum ATI was 0.94-0.89 with Scolioscreen-smartphone, decreased to 0.89-0.75 for smartphone alone, and was 0.95- 0.89 for Scoliometer. Considering Scoliometer measurement taken by surgeon the gold standard, there was excellent consistency with measurements from Scolioscreen-smartphone taken by surgeon (ICC = 0.99), nurse (ICC = 0.95), and parent (ICC = 0.91). Conversely, consistency decreased when surgeon (ICC = 0.86), nurse (ICC = 0.86) and parent (ICC = 0.85) used smartphone alone.

CONCLUSION

Study shows the Scolioscreen-smartphone to overcome limitations associated with ATI measurements using smartphones alone. The Scolioscreen-smartphone provides a reliability and consistency similar to the gold standard (use of Scoliometer by spine surgeon) and enables a parent to take reliable measurements on their own thus offering an accessible and convenient tool for all to use.

Mobile smartphone applications for body position measurement in rehabilitation: a review of goniometric tools

OBJECTIVE

To provide a systematic review of apps for smartphones validated for body position measurement relevant to physical medicine and rehabilitation. TYPE: Systematic search and review.

LITERATURE SURVEY

A literature search was conducted on relevant articles indexed by PubMed before April 15, 2014. We selected only research papers published in English. Papers dealing with apps not relevant to physical medicine and rehabilitation or unavailable on the market were excluded.

METHODOLOGY

Two independent reviewers screened the articles (full text).We analyzed the following information for all apps: target population, object of the measure, body segment evaluated, modality of use, operating platform system, and validation results.

SYNTHESIS

The literature search produced 27 papers, 17 of which met the inclusion criteria for our review. The included papers featured 12 apps validated for angle measurement: 7 were validated exclusively for upper and lower limb joint angles, 4 for spine measurements, ie, cervical or lumbar range of motion and curvature, Cobb angle on radiographs, and the scoliotic distortions of the torso, and 1 for both upper limb and spine measurement. The 12 apps used the inbuilt smartphone magnetometer, accelerometer, or camera to produce angle measurements. Most of the studies assessed the smartphone-apps' reliability (calculating the intraclass correlation coefficients) and validity (showing the limits of agreement).

CONCLUSION

This review highlights the validated goniometer apps that physiatrists and other health care practitioners can use with confidence in research and clinical practice. We found 12 apps corresponding to these criteria, but there is a need for validation studies on available or new apps focused on goniometric measurement in dynamic conditions, eg, during gait or when performing therapeutic exercises.

Optimal management of idiopathic scoliosis in adolescence

Idiopathic scoliosis is a three-dimensional deformity of the growing spine, affecting 2%-3% of adolescents. Although benign in the majority of patients, the natural course of the disease may result in significant disturbance of body morphology, reduced thoracic volume, impaired respiration, increased rates of back pain, and serious esthetic concerns. Risk of deterioration is highest during the pubertal growth spurt and increases the risk of pathologic spinal curvature, increasing angular value, trunk imbalance, and thoracic deformity. Early clinical detection of scoliosis relies on careful examination of trunk shape and is subject to screening programs in some regions. Treatment options are physiotherapy, corrective bracing, or surgery for mild, moderate, or severe scoliosis, respectively, with both the actual degree of deformity and prognosis being taken into account. Physiotherapy used in mild idiopathic scoliosis comprises general training of the trunk musculature and physical capacity, while specific physiotherapeutic techniques aim to address the spinal curvature itself, attempting to achieve self-correction with active trunk movements developed in a three-dimensional space by an instructed adolescent under visual and proprioceptive control. Moderate but progressive idiopathic scoliosis in skeletally immature adolescents can be successfully halted using a corrective brace which has to be worn full time for several months or until skeletal maturity, and is able to prevent more severe deformity and avoid the need for surgical treatment. Surgery is the treatment of choice for severe idiopathic scoliosis which is rapidly progressive, with early onset, late diagnosis, and neglected or failed conservative treatment. The psychologic impact of idiopathic scoliosis, a chronic disease occurring in the psychologically fragile period of adolescence, is important because of its body distorting character and the onerous treatment required, either conservative or surgical. Optimal management of idiopathic scoliosis requires cooperation within a professional team which includes the entire therapeutic spectrum, extending from simple watchful observation of nonprogressive mild deformities through to early surgery for rapidly deteriorating curvature. Probably most demanding is adequate management with regard to the individual course of the disease in a given patient, while avoiding overtreatment or undertreatment.

Validity and reliability of a smartphone application for the assessment of penile deformity in Peyronie's disease

INTRODUCTION

Available methods to evaluate men with Peyronie's disease (PD) are limited by the inability to accurately and reproducibly measure penile deformity. AIM.: The study aims to evaluate the performance of a smartphone application for the measurement of penile curvature and narrowing.

METHODS

A smartphone application, the University of Washington Peyronie's Examination Network (UWPEN), was developed for this purpose. To assess penile curvature, 15 single cylinders of malleable penile prostheses were molded to varying curvature angles. Three blinded observers nonsequentially measured the angle of curvature for each prosthetic cylinder using a protractor, goniometer, and UWPEN. To assess girth narrowing, six clay models of the penile shaft were constructed to represent conditions of normal, partial hourglass, circumferential hourglass, and pencil narrowing. Girth was measured using a ruler and UWPEN by the same blinded observers.

MAIN OUTCOME MEASURES

Statistical analyses compared intertest, interobserver, and intraobserver reliability using the interclass correlation coefficient (ICC). An ICC above 0.75 indicates excellent reproducibility among measurements.

RESULTS

Intertest reliability for angle measurements yielded an ICC for the three methods of 1.000. Separately, the ICC for UWPEN vs. the goniometer and protractor was 0.999 and 0.999, respectively. The interobserver ICC for UWPEN, goniometer, and protractor was 0.998, 0.999, and 1.000, respectively. Intertest reliability for girth narrowing measurements yielded an ICC of 0.991. The interobserver ICC for girth narrowing for UWPEN and the ruler was 0.978 and 0.986, respectively. Intraobserver ICC for angle measurements and girth narrowing showed high reliability for all observers and methods.

CONCLUSIONS

The performance of UWPEN is comparable with and highly correlated with angle measurements obtained from the goniometer and protractor as well as with girth narrowing measurements obtained from a ruler. Measurements are reproducible among different observers. UWPEN may provide a noninvasive, accurate, reliable, and widely accessible method to characterize and track PD over time.