Relationships Between Physical Activity Metrics of Intensity and Diabetes.

INTRODUCTION: Physical activity (PA) prevents diabetes-associated complications. Little is known about what constitutes effective PA interventions to mitigate diabetes. Identifying PA metrics associated with the efficacy of PA interventions will provide insight into devising strategies to treat diabetes. PURPOSE: The aim of this study was to analyze the relationships between preclinical and postclinical variables from a 10-week intervention designed to increase PA in adults with diabetes. METHODS: A secondary analysis was performed to evaluate data using Wilcoxon rank sum test, permutation test and Spearman correlation to analyze hemoglobin A1c (HbA1c), weight, and PA metrics (maximum steps per episode, cadence, daily steps, and 6-minute walk). RESULTS: Poststudy HbA1c level was associated with maximum steps (r = -0.63, P = .03) and 6-minute walk (r = -0.50, P = .09). Baseline weight was associated with average cadence (r = -0.76, P = .007), and poststudy weight was associated with average cadence (r = -0.60, P = .041) and maximum steps (r = -0.62, P = .03). CONCLUSIONS: Cadence and maximum steps per episode reflect PA intensity and were associated with HbA1c and weight in adults with diabetes.

Correction: Using mechanical testing to assess texturing of prosthetic sockets to improve suspension in the transverse plane and reduce rotation.

[This corrects the article DOI: 10.1371/journal.pone.0233148.].

Using mechanical testing to assess the effect of lower-limb prosthetic socket texturing on longitudinal suspension.

To function effectively, a lower limb prosthetic socket must remain securely coupled to the residual limb during walking, running and other activities of daily living; this coupling is referred to as suspension. When this coupling is insufficient longitudinal pistoning of the socket relative to the residual limb occurs. Increasing friction of the socket/liner interface may improve socket suspension and textured sockets may be fabricated relatively easily with 3D printing. The aim of this study was to investigate longitudinal displacement of sockets with different types of textures under two suspension conditions: passive suction and active vacuum. In order to do this, we developed a mock residual limb and mechanical testing protocol. Prosthetic sockets, 14 textured sockets and an Original Squirt-Shape (OSS) Socket, were fabricated from polypropylene copolymer using the Squirt-Shape™ 3D Printer and compared to a smooth socket thermoformed from polypropylene copolymer. Sockets were mounted onto a dual durometer mock residual limb and subjected to four levels of distraction forces (100 N, 250 N, 500 N and 650 N) using a hydraulic material testing system. There was a statistically significant three-way interaction between suspension, force level and texture (p < 0.0005). Longitudinal displacements between textured and reference sockets, for all force levels and both suspension conditions, were significantly different (p < 0.0005). Using these newly developed mechanical testing protocols, it was demonstrated that texturing of polypropylene copolymer sockets fabricated using Squirt-Shape significantly decreased longitudinal displacements compared to a smooth socket. However, none of the novel textured sockets significantly reduced longitudinal displacement compared to the OSS socket under passive suction suspension.

Using mechanical testing to assess texturing of prosthetic sockets to improve suspension in the transverse plane and reduce rotation.

Creating a secure and comfortable linkage between the residual limb and prosthetic socket in persons with lower limb amputation is a critical factor for successful rehabilitation, including ambulation and other activities of daily living. Unwanted rotation within the socket can be a clinical problem for prosthesis users. One way of addressing issues experienced with transverse plane control of the socket may be through increased friction interface forces. It has been proposed that friction at the residual limb/socket interface may be increased by adding texture to interface components. Three-dimensional (3D) printing may be used to fabricate sockets with texture patterns added to the inner socket surface. Hence, the aim of this study was to investigate the effects of socket texturing on transverse plane rotation of the socket on a mock residual limb under two suspension conditions: passive suction and active vacuum. To conduct this study, we developed a mechanical testing protocol as no standardized tests currently exist to assess prosthetic sockets. Sockets with 14 different texture patterns were fabricated using the Squirt-Shape™ 3D printer. Textured sockets were compared to an Original Squirt-Shape (OSS) socket and a smooth thermoformed socket. Sockets were fitted with a mock residual limb and bi-axially loaded to 350 N compression with simultaneous rotation (2.5°, 5° and 7.5°) using a custom rotation assembly attached to a uniaxial hydraulic material testing system. There was a statistically significant three-way interaction between suspension, angle and texture (p < 0.0005). Torques between textured and reference sockets, for all rotation angles and both suspension conditions, were significantly different (p < 0.0005). Using newly developed testing protocols, it was demonstrated that some texture patterns significantly increased torque (i.e., resistance against unwanted rotation) in the transverse plane compared to both OSS and smooth sockets, especially for passive suction. Rotation testing of sockets may provide insight into socket design to improve suspension in the transverse plane.

Feasibility of a Low-Intensity, Technology-Based Intervention for Increasing Physical Activity in Adults at Risk for a Diabetic Foot Ulcer: A Mixed-Methods Study.

BACKGROUND: Among adults with diabetes, 19-34% will develop a diabetic foot ulcer (DFU), which increases amputation risk and health care costs, and worsens quality of life. Regular physical activity, when increased gradually, may help prevent DFUs. In this mixed-methods study, we examined the feasibility of a low-intensity, technology-based behavioral intervention to increase activity in adults at risk for DFUs. METHOD: Participants at risk for a DFU (n = 12; 66% female; mean age = 59.9 years) received four in-person exercise and behavioral counseling sessions over 2-3 weeks, supplemented with use of an activity monitor (to track steps) and text messages (to reinforce behavioral strategies) for an added 8 weeks. Pre- and postintervention assessments of accelerometer measured activity, daily mobility, and glycemic control (A1C) were completed. Treatment acceptability was assessed by questionnaire and via key informant interview. RESULTS: The program appears feasible since all but one participant attended all four sessions, all used the activity monitor and all responded to text messages. Treatment acceptability (scale: 1 = very dissatisfied, 5 = extremely satisfied) was high; average item ratings were 4.79 (SD = 0.24). Participants increased their steps by an average of 881.89 steps/day (d = 0.66). A1C decreased on average by 0.33% (d = 0.23). Daily mobility did not change. Interview results suggest that participants perceived benefits from the intervention. Participant recommended improvements included providing more physical activity information, addressing pain, and intervention delivery in a podiatry clinic. CONCLUSION: Individuals at risk for a DFU might benefit from a minimally intensive, technology-based intervention to increase their physical activity. Future research comparing the intervention to usual care is warranted.