{"id":13628,"date":"2025-07-15T18:12:41","date_gmt":"2025-07-15T16:12:41","guid":{"rendered":"https:\/\/www.wheeleo.eu\/is-the-triceps-surae-truly-a-knee-flexor\/"},"modified":"2025-07-15T18:13:28","modified_gmt":"2025-07-15T16:13:28","slug":"is-the-triceps-surae-truly-a-knee-flexor","status":"publish","type":"post","link":"https:\/\/www.wheeleo.eu\/en\/is-the-triceps-surae-truly-a-knee-flexor\/","title":{"rendered":"Is the Triceps Surae Truly a Knee Flexor?"},"content":{"rendered":"\n

In training or practice, it’s common to hear this phrase:\u201cThe triceps has a knee flexion action.\u201d<\/strong><\/p>\n\n

This is a statement that many physiotherapy students remember.However, this view is incomplete, even misleading<\/strong>, when considering the patient’s functional posture and gait analysis.<\/p>\n\n

Triceps Surae and Closed Chain: a Change in Perspective<\/h2>\n\n

When the foot is free in space<\/strong>, as during an analytical test in prone position, the contraction of the triceps surae<\/strong> (gastrocnemius) can indeed lead to knee flexion<\/strong>, due to its insertion above the joint.<\/p>\n\n

But during walking<\/strong>, or simply when standing<\/strong>, the foot is on the ground<\/strong>.The system is then in a closed chain<\/strong>, and everything changes<\/strong> in the biomechanical logic.<\/p>\n\n

What Happens During Triceps Surae Contraction in a Closed Chain?<\/h2>\n\n

When the triceps contracts strongly (voluntarily or involuntarily, as in spasticity), it produces plantar flexion<\/strong>.But since the foot remains fixed to the ground<\/strong>, the movement is transmitted upwards:<\/p>\n\n

    \n
  • The tibia moves backward<\/strong>,<\/li>\n\n\n\n
  • The knee is pulled backward<\/strong>,<\/li>\n<\/ul>\n\n

    This phenomenon is reinforced by the ground reaction force<\/strong> (GRF), which passes in front of the foot during plantar flexion. This force generates an extension moment that tends to lock the knee in extension<\/strong>, or even cause recurvatum<\/strong> if poorly controlled. <\/p>\n\n

    Triceps Tone: an Essential Balance<\/h2>\n\n

    Triceps tone must be finely regulated<\/strong> to ensure stable and functional walking:<\/p>\n\n

      \n
    • An overly tonic triceps<\/strong> pushes the knee backward \u2192 recurvatum<\/strong>,<\/li>\n\n\n\n
    • A hypotonic triceps<\/strong> no longer supports the chain \u2192 the knee buckles<\/strong>.<\/li>\n<\/ul>\n\n

      This mechanism explains why, in neurology, triceps surae spasticity<\/strong> is one of the main causes of knee recurvatum during walking.<\/p>\n\n

      In Conclusion: Better Understanding for Better Rehabilitation<\/h2>\n\n

      Closed-chain<\/strong> analysis is essential<\/strong> to understand the real effects of muscle contractions during walking.A poor understanding of biomechanics in a real situation (closed chain) leads to analysis errors<\/strong> and inappropriate rehabilitation strategies<\/strong>.<\/p>\n\n

      By understanding this biomechanical logic:<\/p>\n\n

        \n
      • We refine our clinical reasoning<\/strong>,<\/li>\n\n\n\n
      • We better adapt exercises, postures, and technical aids (orthoses, mobility aids, etc.).<\/strong><\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"

        In training or practice, it’s common to hear this phrase:\u201cThe triceps has a knee flexion action.\u201d This is a statement that many physiotherapy students remember.However, this view is incomplete, even misleading, when considering the patient’s functional posture and gait analysis. Triceps Surae and Closed Chain: a Change in Perspective When the foot is free in […]<\/p>\n","protected":false},"author":1,"featured_media":13632,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[109],"tags":[],"profils-type":[],"expertise":[],"situation":[331],"profils-et-pathologies":[],"class_list":["post-13628","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-article","situation-other-articles-health-professional"],"_links":{"self":[{"href":"https:\/\/www.wheeleo.eu\/en\/wp-json\/wp\/v2\/posts\/13628","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.wheeleo.eu\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.wheeleo.eu\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.wheeleo.eu\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.wheeleo.eu\/en\/wp-json\/wp\/v2\/comments?post=13628"}],"version-history":[{"count":1,"href":"https:\/\/www.wheeleo.eu\/en\/wp-json\/wp\/v2\/posts\/13628\/revisions"}],"predecessor-version":[{"id":13629,"href":"https:\/\/www.wheeleo.eu\/en\/wp-json\/wp\/v2\/posts\/13628\/revisions\/13629"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.wheeleo.eu\/en\/wp-json\/wp\/v2\/media\/13632"}],"wp:attachment":[{"href":"https:\/\/www.wheeleo.eu\/en\/wp-json\/wp\/v2\/media?parent=13628"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.wheeleo.eu\/en\/wp-json\/wp\/v2\/categories?post=13628"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.wheeleo.eu\/en\/wp-json\/wp\/v2\/tags?post=13628"},{"taxonomy":"profils-type","embeddable":true,"href":"https:\/\/www.wheeleo.eu\/en\/wp-json\/wp\/v2\/profils-type?post=13628"},{"taxonomy":"expertise","embeddable":true,"href":"https:\/\/www.wheeleo.eu\/en\/wp-json\/wp\/v2\/expertise?post=13628"},{"taxonomy":"situation","embeddable":true,"href":"https:\/\/www.wheeleo.eu\/en\/wp-json\/wp\/v2\/situation?post=13628"},{"taxonomy":"profils-et-pathologies","embeddable":true,"href":"https:\/\/www.wheeleo.eu\/en\/wp-json\/wp\/v2\/profils-et-pathologies?post=13628"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}