TY - CHAP A1 - Risch, Lucie A1 - Bashford, Greg A1 - Kulig, Kornelia A1 - Kaplick, Hannes A1 - Mayer, Frank A1 - Cassel, Michael T1 - Spatial frequency analysis identifies altered local Micromorphology in adolescent athletes with Achilles tendinopathy T2 - Medicine and science in sports and exercise : MSSE ; official journal of the American College of Sports Medicine Y1 - 2020 U6 - https://doi.org/10.1249/01.mss.0000670932.99564.57 SN - 0195-9131 SN - 1530-0315 VL - 52 SP - 82 EP - 82 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - Cassel, Michael A1 - Risch, Lucie A1 - Mayer, Frank A1 - Kaplick, Hannes A1 - Engel, Aaron A1 - Kulig, Kornelia A1 - Bashford, Greg T1 - Achilles tendon morphology assessed using image based spatial frequency analysis is altered among healthy elite adolescent athletes compared to recreationally active controls JF - Journal of science and medicine in sport : official journal of Sports Medicine Australia N2 - Objectives: Although expected, tendon adaptations in adolescent elite athletes have been underreported. Morphologically, adaptations may occur by an increase in collagen fiber density and/or organization. These characteristics can be captured using spatial frequency parameters extracted from ultrasound images. This study aims to compare Achilles tendon (AT) morphology among sports-specific cohorts of elite adolescent athletes and to compare these findings to recreationally active controls by use of spatial frequency analysis. Design: Cross-sectional observational study. Method: In total, 334 healthy adolescent athletes from four sport categories (ball, combat, endurance, explosive strength) and 35 healthy controls were included. Longitudinal ultrasound scans were performed at the AT insertion and midportion. Intra-tendinous-morphology was quantified by performing spatial frequency analysis assessing eight parameters at standardized ROls. Increased values in five parameters suggest a higher structural organization, and in two parameters higher fiber density. One parameter represents a quotient combining both organization and fiber density. Results: Among athletes, only ball sport athletes exhibited an increase in one summative parameter at pre-insertion site compared to athletes from other sport categories. When compared to athletes, controls had significantly higher values of four parameters at pre-insertion and three parameters at midportion site reflecting differences in both, fiber organization and density. Conclusions: Intra-tendinous-morphology was similar in all groups of adolescent athletes. Higher values found in non-athletes might suggest higher AT fiber density and organization. It is yet unclear whether the lesser structural organization in young athletes represents initial AT pathology, or a physiological adaptive response at the fiber cross-linking level. (C) 2019 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved. KW - Tendon structure KW - Adaptation KW - Ultrasound KW - Athletic loading KW - Tendinopathy Y1 - 2019 U6 - https://doi.org/10.1016/j.jsams.2019.03.011 SN - 1440-2440 SN - 1878-1861 VL - 22 IS - 8 SP - 882 EP - 886 PB - Elsevier CY - Oxford ER -