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<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" article-type="research-article" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Pediatric Traumatology, Orthopaedics and Reconstructive Surgery</journal-id><journal-title-group><journal-title xml:lang="en">Pediatric Traumatology, Orthopaedics and Reconstructive Surgery</journal-title><trans-title-group xml:lang="ru"><trans-title>Ортопедия, травматология и восстановительная хирургия детского возраста</trans-title></trans-title-group><trans-title-group xml:lang="zh"><trans-title>Pediatric Traumatology, Orthopaedics and Reconstructive Surgery</trans-title></trans-title-group></journal-title-group><issn publication-format="print">2309-3994</issn><issn publication-format="electronic">2410-8731</issn><publisher><publisher-name xml:lang="en">Eco-Vector</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">625865</article-id><article-id pub-id-type="doi">10.17816/PTORS625865</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>Clinical studies</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>Клинические исследования</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="zh"><subject>Clinical studies</subject></subj-group><subj-group subj-group-type="article-type"><subject>Research Article</subject></subj-group></article-categories><title-group><article-title xml:lang="en">Triceps surae shortening in children</article-title><trans-title-group xml:lang="ru"><trans-title>Ретракция трицепса голени у детей</trans-title></trans-title-group><trans-title-group xml:lang="zh"><trans-title/></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5762-4477</contrib-id><contrib-id contrib-id-type="spin">2068-2102</contrib-id><name-alternatives><name xml:lang="en"><surname>Sapogovskiy</surname><given-names>Andrey V.</given-names></name><name xml:lang="ru"><surname>Сапоговский</surname><given-names>Андрей Викторович</given-names></name><name xml:lang="zh"><surname></surname><given-names></given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>MD, PhD, Cand. Sci. (Med.)</p></bio><bio xml:lang="ru"><p>канд. мед. наук</p></bio><email>sapogovskiy@gmail.com</email><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">H. Turner National Medical Research Center for Сhildren’s Orthopedics and Trauma Surgery</institution></aff><aff><institution xml:lang="ru">Национальный медицинский исследовательский центр детской травматологии и ортопедии имени Г.И. Турнера</institution></aff><aff><institution xml:lang="zh"></institution></aff></aff-alternatives><pub-date date-type="pub" iso-8601-date="2024-03-29" publication-format="electronic"><day>29</day><month>03</month><year>2024</year></pub-date><volume>12</volume><issue>1</issue><issue-title xml:lang="en"/><issue-title xml:lang="ru"/><issue-title xml:lang="zh"/><fpage>19</fpage><lpage>27</lpage><history><date date-type="received" iso-8601-date="2024-01-22"><day>22</day><month>01</month><year>2024</year></date><date date-type="accepted" iso-8601-date="2024-02-06"><day>06</day><month>02</month><year>2024</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2024,</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2024, Эко-Вектор</copyright-statement><copyright-statement xml:lang="zh">Copyright ©; 2024,</copyright-statement><copyright-year>2024</copyright-year><copyright-holder xml:lang="ru">Эко-Вектор</copyright-holder><license><ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">https://eco-vector.com/for_authors.php#07</ali:license_ref></license></permissions><self-uri xlink:href="https://journals.eco-vector.com/turner/article/view/625865">https://journals.eco-vector.com/turner/article/view/625865</self-uri><abstract xml:lang="en"><p><bold>BACKGROUND:</bold> The triceps surae is the main muscle that exerts propulsion power during walking and running. Its retraction changes the biomechanics of the foot, alters locomotion, and results in the secondary development of flatfoot deformity. Literature data on the clinical assessment of triceps surae retraction vary.</p> <p><bold>AIM:</bold> To assess the threshold value of foot dorsiflexion in different clinical assessment methods of determining Achilles tendon shortening.</p> <p><bold>MATERIALS AND METHODS:</bold> The study included the clinical assessment results of foot dorsiflexion in 167 patients (325 feet) with flatfeet aged 7–18 years. The foot dorsiflexion evaluation consisted of the assessment of isolated foot dorsiflexion and foot dorsiflexion with stabilization of the tarsal joints. To determine the involvement of the gastrosoleus complex in the pathological process, foot dorsiflexion was assessed with knee joint flexion and extension. The obtained data were subjected to correlation, regression, and Bland–Altman analyses.</p> <p><bold>RESULTS:</bold> Strong correlations were found when foot dorsiflexion was assessed with the same knee joint position (assessment of isolated foot dorsiflexion and foot dorsiflexion with stabilized tarsal joints and knee joint flexion; the same tests with knee joint extension). Moderate correlations were noted when comparing foot dorsiflexion with knee joint extension and flexion. In the regression analysis, formulas were obtained according to which the threshold values of foot dorsiflexion were calculated in various variants during knee joint flexion and extension, indicating the retraction of the triceps surae: isolated foot dorsiflexion with knee joint extension &lt;20°, isolated foot dorsiflexion with knee flexion &lt;36°, and foot dorsiflexion with tarsal joint stabilization and knee extension &lt;23°.</p> <p><bold>CONCLUSIONS:</bold> Retraction of triceps surae in children with flatfeet equally involves the gastrocnemius and soleus. Differences in the magnitude of foot dorsiflexion with knee joint flexion and extension are the main factors in the retraction of the triceps surae to the gastrocnemius muscle.</p></abstract><trans-abstract xml:lang="ru"><p><bold>Обоснование.</bold> Трицепс голени — основная мышца, обусловливающая пропульсию при ходьбе и беге. Ретракция трицепса голени приводит к изменению биомеханики стопы, нарушению локомоторной функции и вторичному развитию плано-вальгусной деформации стопы. Данные литературы по клинической диагностике ретракции трицепса голени разнятся, что свидетельствует об актуальности настоящего исследования.</p> <p><bold>Цель </bold>— вычисление пороговой величины тыльного сгибания стопы, определяющей ретракцию трицепса голени, в различных вариантах клинической оценки.</p> <p><bold>Материалы и методы.</bold> В исследование вошли результаты клинической оценки тыльного сгибания стопы 167 пациентов (325 стоп) с плоскостопием в возрасте от 7 до 18 лет. При анализе тыльного сгибания стопы оценивалось изолированное тыльное сгибание стопы и тыльное сгибание стопы со стабилизацией суставов предплюсны. Для определения вовлеченности в патологический процесс икроножной и камбаловидной мышц тыльное сгибание стопы оценивалось при сгибании и разгибании коленного сустава. Полученные данные были подвергнуты корреляционному, регрессионному анализу и анализу Bland-Altman.</p> <p><bold>Результаты.</bold> Выявлены сильные корреляционные связи при оценке тыльного сгибания стопы в различных вариантах с одинаковым положением коленного сустава (оценка тыльного сгибания стопы в изолированном виде и при стабилизации суставов предплюсны со сгибанием коленного сустава; такие же варианты оценки тыльного сгибания стопы с разгибанием коленного сустава). Умеренные корреляционные связи отмечены при сравнении тыльного сгибания стопы с разгибанием и сгибанием коленного сустава. При проведении регрессионного анализа получены формулы, по которым рассчитаны пороговые величины тыльного сгибания стопы в различных вариантах при сгибании и разгибании коленного сустава, свидетельствующие о ретракции трицепса голени: изолированное тыльное сгибание стопы при разгибании коленного сустава менее 20°, изолированное тыльное сгибание стопы при сгибании коленного сустава менее 36°, тыльное сгибание стопы при стабилизации суставов предплюсны при сгибании коленного сустава менее 23°.</p> <p><bold>Заключение.</bold> При плоскостопии в сочетании с ретракцией трицепса голени возникает ретракция как икроножной, так и камбаловидной мышцы в равной степени. Различия в величине тыльного сгибания стопы при сгибании и разгибании коленного сустава позволяют заключить, что ограничение тыльного сгибания стопы при ретракции трицепса голени в первую очередь обусловлено ретракцией икроножной мышцы.</p></trans-abstract><trans-abstract xml:lang="zh"><p/></trans-abstract><kwd-group xml:lang="en"><kwd>flatfoot</kwd><kwd>Achilles tendon</kwd><kwd>triceps surae</kwd><kwd>Achilles tendon shortening</kwd><kwd>triceps surae retraction</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>плоскостопие</kwd><kwd>ахиллово сухожилие</kwd><kwd>трицепс голени</kwd><kwd>укорочение ахиллова сухожилия</kwd><kwd>ретракция трицепса голени</kwd></kwd-group><funding-group><award-group><funding-source><institution-wrap><institution xml:lang="en">The Government of the Russian Federation</institution></institution-wrap><institution-wrap><institution xml:lang="ru">Правительство РФ</institution></institution-wrap><institution-wrap><institution xml:lang="zh">The Government of the Russian Federation</institution></institution-wrap></funding-source></award-group></funding-group></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><citation-alternatives><mixed-citation xml:lang="en">Yong JR, Dembia CL, Silder A, et al. 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