Background Freezing of gait, a common symptom of Parkinson’s disease, presents as sporadic episodes in which an individual’s feet suddenly feel stuck to the ground. Inertial measurement units (IMUs) promise to enable at-home monitoring and personalization of therapy, but there is a lack of consensus on the number and location of IMUs for detecting freezing of gait. The purpose of this study was to assess IMU sets in the context of both freezing of gait detection performance and patient preference. Methods Sixteen people with Parkinson’s disease were surveyed about sensor preferences. Raw IMU data from seven people with Parkinson’s disease, wearing up to eleven sensors, were used to train convolutional neural networks to detect freezing of gait. Models trained with data from different sensor sets were assessed for technical performance; a best technical set and minimal IMU set were identified. Clinical utility was assessed by comparing model- and human-rater-determined percent time freezing and number of freezing events. Results The best technical set consisted of three IMUs (lumbar and both ankles, AUROC = 0.83), all of which were rated highly wearable. The minimal IMU set consisted of a single ankle IMU (AUROC = 0.80). Correlations between these models and human raters were good to excellent for percent time freezing (ICC = 0.93, 0.89) and number of freezing events (ICC = 0.95, 0.86) for the best technical set and minimal IMU set, respectively. Conclusions Several IMU sets consisting of three IMUs or fewer were highly rated for both technical performance and wearability, and more IMUs did not necessarily perform better in FOG detection. We openly share our data and software to further the development and adoption of a general, open-source model that uses raw signals and a standard sensor set for at-home monitoring of freezing of gait.

Increased and early lumbopelvic motion during trunk and limb movements is thought to contribute to low back pain (LBP). Therefore, reducing lumbopelvic motion could be an important component of physical therapy treatment. Our purpose was to examine the effects of classification-specific physical therapy treatment (Specific) based on the Movement System Impairment (MSI) model and non-specific treatment (Non-Specific) on lumbopelvic movement patterns during hip rotation in people with chronic LBP. We hypothesized that following treatment people in the Specific group would display decreased lumbopelvic rotation and achieve more hip rotation before lumbopelvic rotation began. We hypothesized that people in the Non-Specific group would display no change in these variables. Kinematic data collected before and after treatment for hip lateral and medial rotation in prone were analyzed. The Specific group (N=16) demonstrated significantly decreased lumbopelvic rotation and achieved greater hip rotation before the onset of lumbopelvic rotation after treatment with both hip lateral and medial rotation. The Non-Specific group (N=16) demonstrated significantly increased lumbopelvic rotation and no change in hip rotation achieved before the onset of lumbopelvic rotation. People who received treatment specific to their MSI LBP classification displayed decreased and later lumbopelvic motion with hip rotation, whereas people who received generalized non-specific treatment did not.

Objective To test the inter-rater reliability of examiners performing the prone instability test (PIT), a clinical test proposed to identify lumbar shear instability. Design Cross-sectional, test-retest design examining subjects with mechanical low back pain (LBP). Setting University-based musculoskeletal analysis laboratory. Participants Thirty subjects with mechanical LBP recruited from community sources in a metropolitan region. Intervention Not applicable. Main Outcome Measures Repeated measures of a clinical examination test proposed to identify lumbar shear instability. Results Inter-rater reliability of examiners’ judgments of the PIT results were indexed with percent agreement and the kappa statistic. Examiners obtained 63 % agreement and a kappa value of 0.10 (95% CI: −0.27 to 0.47). Adjusted kappa values based on prevalence and bias indices were calculated to evaluate the effect on kappa. The prevalence index associated with examiner judgments of the PIT was 0.43 and the bias index was 0.03. The prevalence-adjusted-bias-adjusted kappa value was slightly higher than the unadjusted kappa value (k=0.27; 95% CI: −0.08 to 0.61). Conclusions The results of our study are not consistent with those of previous studies examining reliability of therapists performing the PIT. We conclude that examiners do not attain acceptable inter-rater reliability when performing the procedures for the PIT based on the information that is currently provided in the literature. Based on our experience we suggest further exploration, standardization, and clarification of procedural details to improve therapists’ ability to conduct the PIT on people with LBP.

MPJ extension has a profound effect on increasing forefoot plantar soft tissue stiffness and a consistent but minimal effect on reducing soft tissue thickness. These changes may help transform the foot into a rigid lever at push-off consistent with the theory of the windlass mechanism.

Objective To examine sex differences in lumbopelvic motion and symptom behavior during hip medial rotation in people with low back pain (LBP). We hypothesized that men would demonstrate greater and earlier lumbopelvic motion and would be more likely to report increased symptoms compared to women. Design Cross-sectional observational study. Setting University musculoskeletal analysis laboratory. Participants Thirty men and 29 women with chronic LBP were recruited from the community and a university-based physical therapy clinic. Interventions Not applicable. Main Outcome Measures Lumbopelvic rotation range of motion, amount of hip rotation completed prior to the start of lumbopelvic motion, and provocation of LBP symptoms during the test of prone hip medial rotation were measured. Results Men demonstrated significantly more lumbopelvic rotation (men: 10.0° ± 5.1°, women: 4.5° ± 3.9°; P<0.001) and completed less hip rotation prior to the start of lumbopelvic motion (men: 5.4° ± 3.8°, women: 16.0° ± 13.2°; P<0.001) compared to women. Additionally, a significantly greater percentage of men (60.0%) than women (34.5%; P=0.050) reported increased symptoms with hip medial rotation. Conclusions Men could be at greater risk than women for experiencing LBP symptoms related to hip medial rotation as a result of greater and earlier lumbopelvic motion.