Verification of a Portable Motion Tracking System for Remote Management of Physical Rehabilitation of the Knee.

Rehabilitation following knee injury or surgery is critical for recovery of function and independence. However, patient non-adherence remains a significant barrier to success. Remote rehabilitation using mobile health (mHealth) technologies have potential for improving adherence to and execution of home exercise. We developed a remote rehabilitation management system combining two wireless inertial measurement units (IMUs) with an interactive mobile application and a web-based clinician portal (interACTION). However, in order to translate interACTION into the clinical setting, it was first necessary to verify the efficacy of measuring knee motion during rehabilitation exercises for physical therapy and determine if visual feedback significantly improves the participant's ability to perform the exercises correctly. Therefore, the aim of this study was to verify the accuracy of the IMU-based knee angle measurement system during three common physical therapy exercises, quantify the effect of visual feedback on exercise performance, and understand the qualitative experience of the user interface through survey data. A convenience sample of ten healthy control participants were recruited for an IRB-approved protocol. Using the interACTION application in a controlled laboratory environment, participants performed ten repetitions of three knee rehabilitation exercises: heel slides, short arc quadriceps contractions, and sit-to-stand. The heel slide exercise was completed without feedback from the mobile application, then all exercises were performed with visual feedback. Exercises were recorded simultaneously by the IMU motion tracking sensors and a video-based motion tracking system. Validation showed moderate to good agreement between the two systems for all exercises and accuracy was within three degrees. Based on custom usability survey results, interACTION was well received. Overall, this study demonstrated the potential of interACTION to measure range of motion during rehabilitation exercises for physical therapy and visual feedback significantly improved the participant's ability to perform the exercises correctly.

Foot Strike Run Retraining for Patients With Patellofemoral Chondral Defects: A Case Series.

Military service members (SMs) demonstrate high rates of patellofemoral chondral defects (PFCDs) that are difficult to diagnosis and, if untreated, result in a cascade of events eventually leading to osteoarthritis. Running is an essential occupational task for SMs; however, there is little evidence regarding techniques to maintain running ability in individuals with cartilage defects. The purpose of this case series was to assess the clinical application of foot strike run retraining in patients with PFCDs. This case series included two active duty U.S. Marine Corps SMs who presented to outpatient physical therapy with PFCD, diagnosed via MRI. Both patients attended eight foot strike run retraining sessions. Running mechanics and patient-reported outcomes were recorded pre-training, post-training, and at a 1-month follow-up visit. Both patients successfully converted their strike pattern from a rearfoot to a non-rearfoot strike pattern with training and retained this strategy at 1-month follow-up. Post-intervention, both patients demonstrated increased running tolerance, and improvements in Numeric Pain Rating Scale and Lower Extremity Functional Scale scores. Biomechanical analysis showed that both patients demonstrated a 63% to 70% reduction in average and peak vertical ground reaction force loading rates post-treatment. Modification of foot strike pattern from rear to non-rearfoot strike during running for individuals with PFCD can reduce the magnitude of impact loading, which potentially limits disease progression. These findings suggest that foot strike run retraining may be a feasible strategy to reduce pain and improve function in SMs with PFCD who are required to run for occupational responsibilities.

The Influence of Active, Passive, and Manual Therapy Interventions for Low Back Pain on Opioid Prescription and Health Care Utilization.

OBJECTIVE: The aim of this study was to explore associations between the utilization of active, passive, and manual therapy interventions for low back pain (LBP) with 1-year escalation-of-care events, including opioid prescriptions, spinal injections, specialty care visits, and hospitalizations. METHODS: This was a retrospective cohort study of 4827 patients identified via the Military Health System Data Repository who received physical therapist care for LBP in 4 outpatient clinics between January 1, 2015 and January 1, 2018. One-year escalation-of-care events were evaluated based on type of physical therapist interventions (ie, active, passive, or manual therapy) received using adjusted odds ratios. RESULTS: Most patients (89.9%) received active interventions. Patients with 10% higher proportion of visits that included at least 1 passive intervention had a 3% to 6% higher likelihood of 1-year escalation-of-care events. Similarly, with 10% higher proportion of passive to active interventions used during the course of care, there was a 5% to 11% higher likelihood of 1-year escalation-of-care events. When compared to patients who received active interventions only, the likelihood of incurring 1-year escalation-of-care events was 50% to 220% higher for those who received mechanical traction and 2 or more different passive interventions, but lower by 50% for patients who received manual therapy. CONCLUSION: Greater use of passive interventions for LBP was associated with elevated odds of 1-year escalation-of-care events. In addition, the use of specific passive interventions such as mechanical traction in conjunction with active interventions resulted in suboptimal escalation-of-care events, while the use of manual therapy was associated with more favorable downstream health care outcomes. IMPACT: Physical therapists should be judicious in the use of passive interventions for the management of LBP as they are associated with greater likelihood of receiving opioid prescriptions, spinal injections, and specialty care visits.

Rearfoot Strike Run Retraining for Achilles Tendon Pain: A Two-patient Case Series.

INTRODUCTION: Running-related injuries are prevalent in the military and are often related to physical fitness test training. Non-rearfoot striking while running is known to increase the risk of Achilles tendon injuries because of the high eccentric energy absorption by the elastic components of the planarflexor muscle-tendon complex. However, there is limited evidence to suggest benefits of converting runners with Achilles tendon pain to use a rearfoot strike. METHODS: This is a case series of two active-duty Service members with chronic, running-related Achilles tendon pain that utilized a natural non-rearfoot strike pattern. Both patients were trained to utilize a rearfoot strike while running through the use of real-time visual feedback from wearable sensors. RESULTS: The trained rearfoot strike pattern was retained for over one month after the intervention, and both patients reported improvements in pain and self-reported function. CONCLUSIONS: This case series demonstrated the clinical utility of converting two non-rearfoot strike runners to a rearfoot strike pattern to decrease eccentric demands on the plantarflexors and reduce Achilles tendon pain while running.

Recombination can cause telomere elongations as well as truncations deep within telomeres in wild-type Kluyveromyces lactis cells.

In this study, we examined the role of recombination at the telomeres of the yeast Kluyveromyces lactis. We demonstrated that an abnormally long and mutationally tagged telomere was subject to high rates of telomere rapid deletion (TRD) that preferentially truncated the telomere to near-wild-type size. Unlike the case in Saccharomyces cerevisiae, however, there was not a great increase in TRD in meiosis. About half of mitotic TRD events were associated with deep turnover of telomeric repeats, suggesting that telomeres were often cleaved to well below normal length prior to being reextended by telomerase. Despite its high rate of TRD, the long telomere showed no increase in the rate of subtelomeric gene conversion, a highly sensitive test of telomere dysfunction. We also showed that the long telomere was subject to appreciable rates of becoming elongated substantially further through a recombinational mechanism that added additional tagged repeats. Finally, we showed that the deep turnover that occurs within normal-length telomeres was diminished in the absence of RAD52. Taken together, our results suggest that homologous recombination is a significant process acting on both abnormally long and normally sized telomeres in K. lactis.

Uneven Treadmill Training for Rehabilitation of Lateral Ankle Sprains and Chronic Ankle Instability: Protocol for a Pragmatic Randomized Controlled Trial.

BACKGROUND: Lateral ankle sprains (LASs) are common injuries among military service members. Approximately 40% of individuals with an LAS progress to develop chronic ankle instability (CAI), a condition that results in substantial mechanical and neurophysiological impairment and activity limitation. Since proprioceptive and balance training improve functional outcomes and prevent secondary injury following LAS, they are recommended in clinical practice. Uneven treadmills are an innovative modality that challenge the sensorimotor system while performing an ecologically valid task simulating environments frequently encountered by service members with LAS and CAI. OBJECTIVE: The aim of this study is to evaluate whether the inclusion of uneven treadmill training in standard rehabilitation can improve clinical, functional, biomechanical, and patient-reported outcomes compared with the standard of care alone in service members with LAS and CAI. The prophylactic effects of treatment on secondary injury and identification of any contributing or mediating factors that influence outcomes following treatment will also be evaluated. We hypothesize that service members receiving uneven treadmill training will demonstrate greater improvements in clinical and instrumented measures of impairment, patient-reported function, and lower risk of injury recurrence than the control group immediately post and 18 months following treatment. METHODS: A multisite, parallel randomized clinical trial will be performed among service members aged 18-49 years being treated for LAS and CAI in military treatment facilities in the United States. Participants randomly assigned and allocated to receive the experimental intervention will be provided up to 12 sessions of training on an uneven terrain treadmill over a 6-week treatment course to supplement standard rehabilitation care. Treatment intensity of the rehabilitation exercises and treadmill training will be progressed on the basis of patient-perceived intensity and treatment responses. Outcome measures will include patient-reported outcomes, functional assessments, performance measures, and biomechanical measures. Investigators collecting outcome measures will be blinded to treatment allocation. Reinjury rates and patient-reported outcomes of function will be tracked over 18 months following treatment. RESULTS: The project was funded in September 2020. Patient recruitment began in November 2021, with 3 participants enrolled as of February 2022. Dissemination of the main study findings is anticipated in 2024. CONCLUSIONS: This study will assess the impact of an innovative uneven-terrain treadmill on treatment outcomes in the rehabilitation of service members with LAS and CAI. The results of this study will be used to inform rehabilitation practices and to potentially improve functional outcomes and secondary prevention in this patient population. TRIAL REGISTRATION: ClinicalTrials.gov NCT04999904; https://clinicaltrials.gov/ct2/show/NCT04999904?term=NCT04999904. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/38442.

Preliminary validation of a mobile force Sensing device for clinical and telerehabilitation.

Muscle strength and force production are important measures of patient progress during physical rehabilitation. Reliable and objective measurements are important to ascertain throughout rehabilitation. Current methods-manual muscle testing, electromechanical dynamometer, and hand-held dynamometer-are accurate and reliable, but have limitations that prevent wide implementation. As healthcare systems adapt to more patient-centered outcome models, changes to the delivery of rehabilitation, whether at-home or in the clinic, must also change to become more cost effective and accessible and provide quantifiable information regarding patient progress. We developed a novel Force Sensing (FoSe) device to quantify either tensile or compressive isometric muscle strength. The device was tested in a laboratory setting with healthy participants (n = 32) and compared to the commonly used hand-held dynamometer (HHD). Participants used both devices to perform several common isometric muscle tests including: hip abduction, knee extension, knee flexion, shoulder external rotation, and shoulder internal rotation. Compared to the HHD, FoSe was found to be an accurate and reliable measurement of force production. Intraclass Correlation Coefficients ranged from 0.58 to 0.89 without a magnitude dependent variation in force measurement. A second round of clinical testing with a patient population is warranted to determine FoSe's ability to measure clinically relevant asymmetry and progress over time. Further usability testing also needs to be conducted to determine the adequacy of FoSe for at-home use by both patients and clinicians.

Mutant telomeric repeats in yeast can disrupt the negative regulation of recombination-mediated telomere maintenance and create an alternative lengthening of telomeres-like phenotype.

Some human cancers maintain telomeres using alternative lengthening of telomeres (ALT), a process thought to be due to recombination. In Kluyveromyces lactis mutants lacking telomerase, recombinational telomere elongation (RTE) is induced at short telomeres but is suppressed once telomeres are moderately elongated by RTE. Recent work has shown that certain telomere capping defects can trigger a different type of RTE that results in much more extensive telomere elongation that is reminiscent of human ALT cells. In this study, we generated telomeres composed of either of two types of mutant telomeric repeats, Acc and SnaB, that each alter the binding site for the telomeric protein Rap1. We show here that arrays of both types of mutant repeats present basally on a telomere were defective in negatively regulating telomere length in the presence of telomerase. Similarly, when each type of mutant repeat was spread to all chromosome ends in cells lacking telomerase, they led to the formation of telomeres produced by RTE that were much longer than those seen in cells with only wild-type telomeric repeats. The Acc repeats produced the more severe defect in both types of telomere maintenance, consistent with their more severe Rap1 binding defect. Curiously, although telomerase deletion mutants with telomeres composed of Acc repeats invariably showed extreme telomere elongation, they often also initially showed persistent very short telomeres with few or no Acc repeats. We suggest that these result from futile cycles of recombinational elongation and truncation of the Acc repeats from the telomeres. The presence of extensive 3' overhangs at mutant telomeres suggests that Rap1 may normally be involved in controlling 5' end degradation.