Head Acceleration Events in Male Community Rugby Players: An Observational Cohort Study across Four Playing Grades, from Under-13 to Senior Men.

OBJECTIVES: The aim of this study was to examine the cumulative head acceleration event (HAE) exposure in male rugby players from the Under-13 (U13) to senior club level over 4 weeks of matches and training during the 2021 community rugby season. METHODS: This prospective, observational cohort study involved 328 male rugby players. Players were representative of four playing grades: U13 (N = 60, age 12.5 ± 0.6 years), U15 (N = 100, age 14.8 ± 0.9 years), U19 (N = 78, age 16.9 ± 0.7 years) and Premier senior men (N = 97, age 22.5 ± 3.1 years). HAE exposure was tracked across 48 matches and 113 training sessions. HAEs were recorded using boil-and-bite instrumented mouthguards (iMGs). The study assessed the incidence and prevalence of HAEs by ages, playing positions, and session types (match or training). RESULTS: For all age grades, weekly match HAE incidence was highest at lower magnitudes (10-29 g). Proportionally, younger players experienced higher weekly incidence rates during training. The U19 players had 1.36 times the risk of high-magnitude (> 30 g) events during matches, while the U13 players had the lowest risk compared with all other grades. Tackles and rucks accounted for the largest HAE burden during matches, with forwards having 1.67 times the risk of > 30 g HAEs in rucks compared with backs. CONCLUSIONS: This study provides novel data on head accelerations during rugby matches and training. The findings have important implications for identifying populations at greatest risk of high cumulative and acute head acceleration. Findings may guide training load management and teaching of skill execution in high-risk activities, particularly for younger players who may be exposed to proportionally more contact during training and for older players during matches.

Digital Technologies for Women's Pelvic Floor Muscle Training to Manage Urinary Incontinence Across Their Life Course: Scoping Review.

BACKGROUND: Women with urinary incontinence (UI) may consider using digital technologies (DTs) to guide pelvic floor muscle training (PFMT) to help manage their symptoms. DTs that deliver PFMT programs are readily available, yet uncertainty exists regarding whether they are scientifically valid, appropriate, and culturally relevant and meet the needs of women at specific life stages. OBJECTIVE: This scoping review aims to provide a narrative synthesis of DTs used for PFMT to manage UI in women across their life course. METHODS: This scoping review was conducted in accordance with the Joanna Briggs Institute methodological framework. A systematic search of 7 electronic databases was conducted, and primary quantitative and qualitative research and gray literature publications were considered. Studies were eligible if they focused on women with or without UI who had engaged with DTs for PFMT, reported on outcomes related to the use of PFMT DTs for managing UI, or explored users' experiences of DTs for PFMT. The identified studies were screened for eligibility. Data on the evidence base for and features of PFMT DTs using the Consensus on Exercise Reporting Template for PFMT, PFMT DT outcomes (eg, UI symptoms, quality of life, adherence, and satisfaction), life stage and culture, and the experiences of women and health care providers (facilitators and barriers) were extracted and synthesized by ≥2 independent reviewers. RESULTS: In total, 89 papers were included (n=45, 51% primary and n=44, 49% supplementary) involving studies from 14 countries. A total of 28 types of DTs were used in 41 primary studies, including mobile apps with or without a portable vaginal biofeedback or accelerometer-based device, a smartphone messaging system, internet-based programs, and videoconferencing. Approximately half (22/41, 54%) of the studies provided evidence for or testing of the DTs, and a similar proportion of PFMT programs were drawn from or adapted from a known evidence base. Although PFMT parameters and program compliance varied, most studies that reported on UI symptoms showed improved outcomes, and women were generally satisfied with this treatment approach. With respect to life stage, pregnancy and the postpartum period were the most common focus, with more evidence needed for women of various age ranges (eg, adolescent and older women), including their cultural context, which is a factor that is rarely considered. Women's perceptions and experiences are often considered in the development of DTs, with qualitative data highlighting factors that are usually both facilitators and barriers. CONCLUSIONS: DTs are a growing mechanism for delivering PFMT, as evidenced by the recent increase in publications. This review highlighted the heterogeneity in types of DTs, PFMT protocols, the lack of cultural adaptations of most of the DTs reviewed, and a paucity in the consideration of the changing needs of women across their life course.

Anticipatory head control mechanisms in response to impact perturbations: An investigation of club rugby players with and without a history of concussion injury.

OBJECTIVES: The primary objective of this study was to examine rugby players anticipatory and compensatory head control during predictable and unpredictable impact events. METHODS: An observational cross-sectional study design. Fifty-one (17_healthy 34_concussion) male rugby players were exposed to external predictable and unpredictable impact perturbations at mid-chest level. Surface EMG of the upper-trapezius (UT), splenius-capitis (Spl) and sternocleidomastoid (Scm) was recorded and analysed across three temporal epochs typical for anticipatory and compensatory postural control. Synchronized sagittal head-kinematics were measured from high-speed video (500 fps). Nonparametric tests were used to examine within and between group effects. RESULTS: Anticipatory head control was evident in predictable conditions, expressed by early posterior head displacement and activation of the Spl. Compared to unpredictable conditions, muscle amplitudes were significantly lower, as was head acceleration. Compared to Healthy, the Concussion athletes lacked early activation of the Spl, exhibited delayed anticipatory head adjustments and experienced higher head accelerations in predictable conditions. CONCLUSION: Rugby players with concussion injuries have significant deficits in cervical spinal motor control. The concussed motor control strategy leads to higher inertial head accelerations and delayed anticipatory head displacements. Effects may persist for two or more years following injury, which may indicate re-injury vulnerability in these athletes.

Management of women with pregnancy-related pelvic girdle pain: an international Delphi study.

OBJECTIVES: Pregnancy-related pelvic girdle pain (PPGP) contributes to significant prenatal and postpartum impairments; however, various clinical practices exist around the conservative treatment of this condition. This study sought to reach a consensus on the essential components of PPGP management through an international Delphi survey of experts in women's health. DESIGN AND PARTICIPANTS: Eighty-seven international experts in the field of PPGP were invited to participate and surveyed over three rounds. Round 1 of the survey utilised open-ended questions to gain feedback on 16 components of PPGP management previously identified by a focus group. Feedback from panel members guided modification and refinement of questions for Rounds 2 and 3. A 5-point Likert scale was used to rate level of agreement, with a minimum threshold for consensus of ≥75% agreement set across all survey rounds. RESULTS: Forty-four of the 87 (50%) invited professionals agreed to participate in the panel, with 77% (34/44) of panellists contributing to all three rounds. Of the 16 initial components, 15 were included in Round 2. The final consensus was reached on 10 important components of assessment and management after Round 3: pain education, postural and ergonomic advice, social and lifestyle factors, psychological factors, cultural considerations, strengthening exercise, other exercise, exercise precautions, manual therapy and the use of crutches. CONCLUSION: This study identified 10 key components that should be considered in the management of PPGP. In addition, these components provide a potential framework for future research around the conservative management of PPGP.

A multivariate model for predicting PPGP considering postural adjustment parameters.

BACKGROUND: Prospective studies have described evidence about the risk of developing pregnancy-related pelvic girdle pain (PPGP) such as, parity, previous history of low back and pelvic girdle pain. No previous studies have prospectively associated PPGP with postural control. AIM: This study aimed to identify postural control predictors of PPGP during pregnancy. METHODS: Forty-six pregnant women were surveyed throughout their pregnancy for the presence of PPGP. At baseline, participants were evaluated for muscle latencies, mediolateral centre-of-pressure (COP) displacement and velocity during single-leg lift performed with eyes open and closed. PPGP was considered if they presented with one positive clinical assessment as well as pain within the pelvic area. RESULTS: Eighteen (45%) of the participants developed PPGP. This group presented with PPGP around a mean 29th week (SD = 5.7), with mean pelvic pain intensity of 4 mm VAS (SD = 2) on a (0-10 cm VAS) and mean PPGP questionnaire score of 21.5 points (SD = 10.6) out of a possible 100 points with 0 indicating no functional disability. The two factors that were significantly associated with PPGP were the right and left biceps femoris (BF) muscle. For every 50 ms of difference of BF muscles latency between eyes open and closed, the risk of PPGP increases by 20% (right BF) and 30% (left BF) to develop PPGP. CONCLUSION(S): This study shows that BF muscle delay during single-leg lift presented at baseline was a significant predictor for the development of PPGP in late pregnancy.

Anticipatory postural control differs between low back pain and pelvic girdle pain patients in the absence of visual feedback.

PURPOSE: The aim of this study was to examine the effect of vision on anticipatory postural control (APA) responses in two groups of clinically diagnosed chronic low back pain patients, those with Posterior Pelvic Girdle pain and those with Non-Specific Low Back Pain compared to a matched group of healthy controls during the modified Trendelenburg task. METHODS: Seventy-eight volunteer participants (60 females and 18 males) gave informed consent to take part in this study. 39 with confirmed LBP or PGP lasting longer than 12 weeks and 39 healthy matched controls performed 40 single leg lift tasks (hip flexion to 90° as quickly as possible) with their non-dominant lower limb. A force plate was used to determine the medial-lateral displacement of the center of pressure, and the initiation of weight shift; kinematics was used to determine initiation of leg lift; and electromyography was used to determine onset times from the external oblique (EO), internal oblique (IO) and lumbar multifidus (MF), gluteus maximus (GM) and biceps femoris (BF). RESULTS: The PGP group showed significantly longer muscle onset latencies in the BF, EO MF with visual occlusion (F2,746 = 4.51, p < .0001). CONCLUSION: The muscle onset delays identified between the two LBP sub-groups suggests that pain may not be the primary factor in alteration of APA response. The PGP group show a greater reliance on vision which may signal impairment in multiple feedback channels.

Assessing the construct validity of clinical tests to identify sacroiliac joint inflammation in patients with non-radiographic axial spondyloarthritis.

AIM: Magnetic resonance imaging (MRI) can be used to identify sacroiliac joint (SIJ) inflammation and provide an earlier diagnosis of nonradiographic axial spondyloarthritis (nrAxSpA). However, MRI is frequently a resource-limited examination. Our aim was to assess if a set of physical clinical tests can identify SIJ inflammation in patients with nrAxSpA. METHODS: Twenty participants with nrAxSpA underwent two functional tests (active straight leg raise, and stork test on the support side) and four pain provocation tests (Gaenslen's, posterior pelvic pain provocation, Patrick's Faber and palpation of the long dorsal SIJ ligament) for the SIJ, and then proceeded to a contemporaneous reference standard MRI. The Spondyloarthritis Research Consortium of Canada scoring system (SPARCC) was used to score MRI. Specificity, sensitivity, and likelihood ratios (LR) were calculated for individual clinical tests, and for the composite of tests. RESULTS: Pain provocation tests were superior to functional tests, which showed poor accuracy. The Patrick's Faber test was the best performing procedure (sensitivity 71%, specificity 75%, positive LR 2.9, negative LR 0.4). When combining the provocation tests, a positive test in one out of two tests demonstrated the strongest predictive value (sensitivity 86%, specificity 62%, positive LR 2.2, negative LR 0.2). CONCLUSIONS: Sacroiliac joint pain provocation tests correlate modestly with inflammation. The Patrick's Faber test showed the greater LR to identify SIJ inflammation in patients with nrAxSpA. SIJ pain provocation tests may offer a simple and cost-effective way of identifying patients with nrAxSpA who are most likely to have MRI evidence of inflammation.

Reliability of surface electromyography activity of gluteal and hamstring muscles during sub-maximal and maximal voluntary isometric contractions.

BACKGROUND: Normalizing to a reference signal is essential when analysing and comparing electromyography signals across or within individuals. However, studies have shown that MVC testing may not be as reliable in persons with acute and chronic pain. OBJECTIVES: The purpose of this study was to compare the test-retest reliability of the muscle activity in the biceps femoris and gluteus maximus between a novel sub-MVC and standard MVC protocols. METHODS: This study utilized a single individual repeated measures design with 12 participants performing multiple trials of both the sub-MVC and MVC tasks on two separate days. The participant position in the prone leg raise task was standardised with an ultrasonic sensor to improve task precession between trials/days. Day-to-day and trial-to-trial reliability of the maximal muscle activity was examined using ICC and SEM. FINDINGS: Day-to-day and trial-to-trial reliability of the EMG activity in the BF and GM were high (0.70-0.89) to very high (≥0.90) for both test procedures. %SEM was <5-10% for both tests on a given day but higher in the day-to-day comparisons. The lower amplitude of the sub-MVC is a likely contributor to increased %SEM (8-13%) in the day-to-day comparison. CONCLUSIONS: The findings show that the sub-MVC modified prone double leg raise results in GM and BF EMG measures similar in reliability and precision to the standard MVC tasks. Therefore, the modified prone double leg raise may be a useful substitute for traditional MVC testing for normalizing EMG signals of the BF and GM.

Sex differences in anticipatory postural adjustments during rapid single leg lift.

The aim of this study was to assess the influence of sex on the kinetic, kinematic and neuromuscular correlates of anticipatory postural adjustments (APAs) during a single leg lift task performed by healthy participants. Fifty healthy age and body mass index matched participants (25 women and 25 men) performed 20 single leg lift task (hip flexion to 90 ° as quickly as possible) with their dominant and their non-dominant lower limbs. A force plate was used to determine the medial-lateral displacement of the center of pressure (COPML), and the initiation of weight shift (T0); kinematics was used to determine leg lift (T1); and electromyography was used to determine onset times from eight muscles: bilateral external oblique, internal oblique and lumbar multifidus, and unilateral (stance limb) gluteus maximus and biceps femoris. Movement control limb dominance was included in the analysis. Statistically significant interactions between sex and limb dominance (p < .001) were observed for T1, COPML, and muscle onsets. Also, statistically significant main effect of sex on T0 was observed. Women showed increased APA time (T1) and magnitude (COPML) in their dominant limbs compared to men. Such differences between sexes did not occur in the non-dominant limb. Women recruited proximal muscles later than their man counterparts. Overall, women appear to have a stronger effect of limb dominance on their anticipatory postural control strategy which requires further investigation. The findings of the current study indicate that women and men differ in their anticipatory postural control strategy for rapid single leg lift.

Innominate segment deformation during passive hip abduction and external rotation.

BACKGROUND: Electromagnetic palpation-digitization technique for measurement of innominate motion involves calculation of innominate rotation using the innominate vector length in the neutral (NEUT) and combined hip abduction and external rotation (HABER) test positions. The innominate vector length [i.e., the segment between anterior superior iliac spine (ASIS) and posterior superior iliac spine (PSIS)] is not a rigid structure and its deformation could introduce an error influencing the final innominate rotation measurement. OBJECTIVES: The aim of this study is to determine if there is significant deformation occurring in innominate vector length when the hip is loaded into the HABER test position. METHOD: A cross sectional study using sixteen healthy individuals and a single tester was conducted. Four pelvic landmarks, left and right PSIS and ASIS, were palpated and digitized using 3D digitizing stylus of Polhemus electromagnetic tracking device, in two hip test positions, NEUT and 50° HABER. The innominate vector lengths were calculated from the 3D coordinates of pelvic landmarks, for each hip test positions. RESULTS AND CONCLUSION: Paired t-tests demonstrated no significant differences (p > 0.05) in the innominate vector lengths at the side of the load as well as the opposite innominate when either the right or left hip was loaded; thus indicating no significant bone deformation in innominate segment during the HABER test position.

Does repeated palpation-digitization of pelvic landmarks for measurement of innominate motion introduce a systematic error?--A psychometric investigation.

BACKGROUND: Palpation-digitization technique for measurement of innominate motion involves repeated manual palpation-digitization of pelvic landmarks, which could introduce a systematic variation between subsequent trials and thereby influence final innominate angular measurement. OBJECTIVES: The aim of this study is to quantify the effect of repeated palpation-digitization errors on overall variability of innominate vector length measurements; and to determine if there is a systematic variation between subsequent repeated trials. METHOD: A single group repeated measures study, using four testers and fourteen healthy participants, was conducted. Four pelvic landmarks, left and right posterior superior iliac spine and anterior superior iliac spine, were palpated and digitized using 3D digitizing stylus of Polhemus electromagnetic tracking device, for ten consecutive trials by each tester in their random order. The ten individual trials of innominate vector lengths measured by each tester for each participant were used for the analysis. RESULTS AND CONCLUSIONS: Repeated measures ANOVA demonstrated a very small effect of repeated trial factor (≤0.66%) as well as error component (≤0.32%) on innominate vector length variability. Further, residual versus order plots demonstrated a random pattern of errors across zero; thus indicating no systematic variation between subsequent trials of innominate vector length measurements.

Can hip abduction and external rotation discriminate sacroiliac joint pain?

AIM: The primary aim of the study is to determine if Hip Abduction and External Rotation (HABER) test is capable of reproducing familiar pain in individuals with low back pain (LBP) of sacroiliac joint (SIJ) origin (SIJ-positive) when compared with LBP of Non-SIJ origin (SIJ-negative). If so, the secondary aim is to determine the diagnostic accuracy of HABER test against the reference standard of pain provocation tests, and to determine which increments of the HABER test has highest sensitivity and specificity for identifying SIJ-positive individuals. DESIGN: Single-blinded diagnostic accuracy study. METHOD: Participants [n(122)] between ages of 18-50 y, suffering from chronic non-specific LBP (≥3 months) volunteered in the study. An experienced musculoskeletal physiotherapist evaluated and classified participants into either SIJ-positive [n(45)] or SIJ-negative [n(77)], based on reference standard of pain provocation tests [≥3 positive tests = SIJ-positive]. Another musculoskeletal physiotherapist, blinded to clinical groups, evaluated participants for reproduction of familiar pain during each increment (10°, 20°, 30°, 40°, and 50°) of HABER test. RESULTS: The HABER test reproduced familiar pain in SIJ-positive individuals when compared with SIJ-negative individuals [p (0.001), R(2) (0.38), Exp(ß) (5.95-10.32)], and demonstrated moderate level of sensitivity (67%-78%) and specificity (71%-72%) for identifying SIJ-positive individuals. Receiver operator curve analysis demonstrated that the HABER increments of ≥30° have the highest sensitivity (83%-100%) and specificity (52%-64%). CONCLUSIONS: The HABER test is capable of reproducing familiar pain in SIJ-positive LBP individuals and has moderate levels of sensitivity and specificity for identifying SIJ-positive LBP individuals.

Gluteus medius coactivation response in field hockey players with and without low back pain.

OBJECTIVES: To examine the effect of prolonged standing on gluteus medius coactivation and to observe whether the changes in gluteus medius coactivation over time were related to the development of low back pain in elite female field hockey players. DESIGN: Prospective cohort design. METHODS: Participants were 39 elite female field hockey players (14 with a history of low back pain). Before the prolonged stand, maximal hip abduction strength, side bridge hold endurance and hip abduction range of motion were measured bilaterally. Surface electromyography was collected from the gluteus medius for coactivation analysis during a prolonged stand for 70 min. Low back pain was rated every 10 min on a visual analogue scale. RESULTS: Fourteen of 39 participants developed low back pain. The Time effect was significant for gluteus medius coactivation response (p = 0.003) and visual analogue scale score (p < 0.001). There were no significant group × time interactions. Yet athletes who developed pain had higher coactivation for the majority of the stand task. CONCLUSIONS: While female field hockey players have high agonist-antagonist coactivation patterns during prolonged standing, stand task is a useful tool to predict low back pain occurrence in players with and without history of pain.

Construct validity of clinical spinal mobility tests in ankylosing spondylitis: a systematic review and meta-analysis.

The study aimed to determine, using systematic review and meta-analysis, the level of evidence supporting the construct validity of spinal mobility tests for assessing patients with ankylosing spondylitis. Following the guidelines proposed in the Preferred Reporting Items for Systematic reviews and Meta-Analyses, three sets of keywords were used for data searching: (i) ankylosing spondylitis, spondyloarthritis, spondyloarthropathy, spondylarthritis; (ii) accuracy, association, construct, correlation, Outcome Measures in Rheumatoid Arthritis Clinical Trials, OMERACT, truth, validity; (iii) mobility, Bath Ankylosing Spondylitis Metrology Index-BASMI, radiography, spinal measures, cervical rotation, Schober (a further 19 keywords were used). Initially, 2558 records were identified, and from these, 21 studies were retained. Fourteen of these studies were considered high level of evidence. Compound indexes of spinal mobility showed mostly substantial to excellent levels of agreement with global structural damage. Individual mobility tests for the cervico-thoracic spine showed only moderate agreements with cervical structural damage, and considering structural damage at the lumbar spine, the original Schober was the only test that presented consistently substantial levels of agreement. Three studies assessed the construct validity of mobility measures for inflammation and low to fair levels of agreement were observed. Two meta-analyses were conducted, with assessment of agreement between BASMI and two radiological indexes of global structural damage. The spinal mobility indexes and the original Schober test show acceptable construct validity for inferring the extent of structural damage when assessing patients with ankylosing spondylitis. Spinal mobility measures do not reflect levels of inflammation at either the sacroiliac joints and/or the spine.

Innominate movement patterns, rotation trends and range of motion in individuals with low back pain of sacroiliac joint origin.

BACKGROUND: Innominate kinematic anomalies resulting in low back pain (LBP) of sacroiliac joint (SIJ) origin (SIJ-positive), has always been a topic of contention, owing to difficultly in its evaluation. Recent technique of electromagnetic palpation-digitization has been able to accurately quantify innominate kinematics in healthy individuals. OBJECTIVES: The purpose of this study is to determine if participants with LBP of SIJ origin (SIJ-positive) demonstrate significantly different innominate kinematics than participants with LBP of non-SIJ origin (SIJ-negative). DESIGN: Single-blinded cross-sectional case-control study. METHOD: Participants [n(122)] between the ages of 18 to 50 years, suffering from chronic non-specific LBP (≥3 months) volunteered in the study. An experienced musculoskeletal physiotherapist evaluated and classified participants into either SIJ-positive [n(45)] or SIJ-negative [n(77)] group, using the reference standard pain provocation tests [≥3 positive tests = SIJ-positive]. A research physiotherapist, blinded to clinical groups, conducted the innominate kinematic testing using a valid and reliable electromagnetic palpation-digitization technique, during prone lying incremental hip abduction-external rotation test positions. RESULTS: The results of the mixed model regression analyses demonstrated that SIJ-positive participants exhibited significantly different innominate movement patterns and trends of rotation, but not innominate ranges of motion, when compared with SIJ-negative LBP participants. CONCLUSIONS: These findings demonstrate association between SIJ pain and altered innominate kinematics, and have led the groundwork for further exploration of clinical measurement, relevance, and management of these potentially important movement observations.

Role of Physical Evaluation in the Early Identification of Axial Spondyloarthritis: A Research Proposal.

The aim of this study was to present a rationale to explore the use of clinical tests for the sacroiliac joints to detect early axial spondyloarthritis (SpA) and to suggest a protocol to validate these clinical tests. Based on the European Guidelines for Diagnosis and Treatments of Pelvic Girdle Pain, we propose a set of six clinical tests to identify the likely presence of inflammation in the sacroiliac joints associated with early axial SpA. As magnetic resonance imaging (MRI) is the current gold standard used to identify inflammation in the sacroiliac joints, the results of the proposed set of clinical tests are compared with those from the MRI examinations. We hypothesize that specific clinical tests, which combine pain provocation and functional tests, for assessing the sacroiliac joints will help to identify early active inflammation at the sacroiliac joints in axial SpA. If such tests prove to be sensitive and specific, they could add further value to the diagnostic classification criteria for axial SpA.

Asymmetric pelvic bracing and altered kinematics in patients with posterior pelvic pain who present with postural muscle delay.

BACKGROUND: The purpose of the study was to examine the muscle activity and hip-spine kinematics in a group of individuals diagnosed with posterior pelvic girdle pain and confirmed postural muscle delay during a repeated fast hip flexion task. METHODS: Twenty-four (12 pain and 12 control) age and sex matched participants performed a repeated fast hip flexion task to auditory signal. Surface EMG activity in the external and internal oblique, the multifidus, the gluteus maximus and biceps femoris in the stance-limb was examined for onset timing and EMG integral. Sagittal plane hip (swing limb) and spine kinematics were examined for group and side differences over the repeated trials. FINDINGS: While the pain group lacked significant feedforward muscle activity they displayed higher muscle activity at movement onset in the biceps femoris bilaterally (p<0.05) as well as the external oblique (p<0.05) during motion of the symptomatic side. Furthermore, the pain group experienced asymmetrical spinal range of motion with increased motion on the contralateral side (p<0.001) and reduced flexion velocity on the symptomatic side (p<0.001). INTERPRETATION: The findings support previous hypotheses regarding the effect of increased biceps activity on pelvic control during lumbo-pelvic rotation. Further, there appears to be a symptom led strategy for bracing the innominate through opposing tension in the biceps and external oblique during movement of the painful side. Such asymmetrical pelvic girdle bracing may be a strategy to increase the stability of the pelvis in light of the failed load transfer mechanism. Putatively, this strategy may increase the mechanical stress on the sacroiliac joint exacerbating pain complaints.

Criterion-concurrent validity of spinal mobility tests in ankylosing spondylitis: a systematic review of the literature.

OBJECTIVE: To examine the level of evidence for criterion-concurrent validity of spinal mobility assessments in patients with ankylosing spondylitis (AS). METHODS: Guidelines proposed in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses were used to undertake a search strategy involving 3 sets of keywords: accura*, truth, valid*; ankylosing spondylitis, spondyloarthritis, spondyloarthropathy, spondylarthritis; mobility, spinal measure*, (a further 16 keywords with similar meaning were used). Seven databases were searched from their inception to February 2014: AMED, Embase, ProQuest, PubMed, Science Direct, Scopus, and Web of Science. The Quality Assessment of Diagnostic Accuracy Studies (with modifications) was used to assess the quality of articles reviewed. An article was considered high quality when it received "yes" in at least 9 of the 13 items. RESULTS: From the 741 records initially identified, 10 articles were retained for our systematic review. Only 1 article was classified as high quality, and this article suggests that 3 variants of the Schober test (original, modified, and modified-modified) poorly reflect lumbar range of motion where radiographs were used as the reference standard. CONCLUSION: The level of evidence considering criterion-concurrent validity of clinical tests used to assess spinal mobility in patients with AS is low. Clinicians should be aware that current practice when measuring spinal mobility in AS may not accurately reflect true spinal mobility.

Can innominate motion be used to identify persons with ankylosing spondylitis? A pilot study.

Innominate movements during hip abduction and external rotation have recently been described in healthy individuals. In the present study the aim was to determine whether these hip movement tests could discriminate altered movement patterns in people with specific pelvic girdle pain (PGP) disorder. This pilot study is the first step in determining the usefulness of prone hip abduction and external rotation in the differential diagnosis of PGP disorders. A cross-sectional comparison between a convenient sample of 6 individuals who had been referred for exercise and advice following diagnosis of ankylosing spondylitis (AS) via a Medical/Rheumatological pathway and 18 healthy age and gender matched controls. Transverse and sagittal plane innominate motion was measured using a palpation and digitizing technique with a magnetic tracking device. Data analysis involved applying best-fit equations to the data and visual inspection of the produced graphs as well as conditional logistical regression for each test position to determine our ability to predict group association. Graphical comparisons demonstrate a distinction between the patients with AS and the healthy controls. Further, for all three hip conditions the innominate angle was a significant predictor of group association (p = 0.002 for AB, p = 0.005 for AB + ER and p = 0.007 for ER).

Validity and reliability of palpation-digitization for non-invasive kinematic measurement - a systematic review.

Joint kinematic assessment using an electromagnetic tracking device (EMTD) requires palpation-digitization (PD) of bony landmarks to define the anatomical axes. Errors in PD of bony landmarks can perturb the anatomical axes and affect the validity and reliability of kinematic measurements. The validity and reliability of PD for kinematic measurement needs to be explored before recommending its wider use. A systematic search of 15 electronic databases located studies assessing validity and/or reliability of PD for joint kinematic assessment. Two independent reviewers used the QUADAS and QAREL tools to assess quality of validity and reliability studies respectively. The results were synthesized qualitatively using a level of evidence approach. Eight studies satisfied the final eligibility criteria and were included in the review. The validity, intra-rater reliability and inter-rater reliability were assessed in three, seven and one study respectively. The overall level of evidence for validity of PD technique was strong with high correlation (≥0.80) reported by three high (≥60%) quality studies. The overall level of evidence for intra-rater reliability was also strong with very high ICC (≥0.90) and satisfactory SEM (SEM% ≤ 10%) reported by four high quality studies. However the level of evidence for inter-rater reliability was limited and needs to be addressed by future research.