Study Design: Case-control study.Purpose: To investigate the independent associations of back pain with sarcopenia and with back muscle degeneration, and to introduce a new risk index for back muscle degeneration.Overview of Literature: The Asian Working Group for Sarcopenia recommends diagnosis using handgrip strength, gait speed, and skeletal muscle mass. However, these criteria do not strongly reflect back muscle degeneration.Methods: Patients who completed a questionnaire on back-pain between October 2016 and October 2017 were enrolled in this study. Appendicular skeletal muscle index (ASMI), cross-sectional area (CSA) index, fatty infiltration (FI) rate of the paraspinal muscles, and lumbar extensor strength index (LESI) were measured and compared between no back-pain and back-pain group. Correlations between LESI and ASMI, CSA index, and FI rate were analyzed. The back-pain group was further divided according to ASMI into sarcopenia and non-sarcopenia subgroups and by our newly developed back muscle degeneration risk index based on correlation coefficients between LESI and CSA index, FI rate. Differences in ASMI, CSA index, FI rate, LESI, and Visual Analog Scale (VAS) score between subgroups were analyzed.Results: The ASMI, CSA index, FI rate, and LESI differed significantly between back-pain and pain-free groups. The LESI demonstrated the strongest correlation with FI rate. There were no significant differences in VAS score and back muscle degeneration index in the back-pain group when divided according to the presence of sarcopenia. However, there was a significant difference in VAS score between back-pain patients when classified according to high and low back muscle degeneration risk index.Conclusions: We suggest that the degree of back pain is more strongly associated with back muscle degeneration than with sarcopenia. This back muscle degeneration risk index, reflecting both back muscle morphology and function, could be a useful parameter for evaluation of back pain and muscle degeneration.

No abstract

Flatfoot is a commonly observed three-dimensional foot deformity combined with hindfoot valgus, reduced me-dial longitudinal arch height, and forefoot abduction. 1,2) Midfoot breakage causes a decrease in the hardness of the lever. Forefoot abduction and heel valgus cause the propulsive force to be less effective as the muscles act in a different direction to the lever at a certain angle. In terms of kinematics, the flatfoot leads to lever arm dysfunction due to the flexible, short lever arm. 3,4) Thus, to produce push-off moments on the sagittal plane during gait, the gastrocnemius-soleus complex should generate more

No abstract

The present paper describes predictions of Full Coverage Film Cooling. The calculations have been performed by a quasi-three dimensional model that account for the basically three dimensional nature of the flow. The quasi-three dimensional model are solved by finite analytic method, modified simpler algorithm and body fitted coordinate systems. The turbulent stresses and heat fluxes are obtained from the low Reynolds K-ε turbulence model. The results are given for flows over flat plates for different injection angles, relative spacings, blowing rates and injection temperatures.