[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Lower limb](https://durgical.com/en/anatomy/region/lower-limb/) › Soleus [Muscular system](https://durgical.com/en/anatomy/system/muscular-system/) · [Lower limb](https://durgical.com/en/anatomy/region/lower-limb/) # Soleus The soleus is a broad, deep calf muscle under the gastrocnemius; it points the foot and keeps the body steady when standing. Official name: Soleus muscle [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=lower_limb&select=soleus&side=r) Opens in the Durgical app, no sign-up needed. ## What it is A broad, deep calf muscle under the gastrocnemius. ## What it does Points the foot and keeps you steady when standing. ## Key points - A one-joint muscle (it does not cross the knee): it keeps working with the knee bent, when the gastrocnemius is slack - Its venous sinuses drive the calf muscle pump, and deep vein thrombosis often starts in the soleal veins - Its tendinous arch between [tibia](https://durgical.com/en/anatomy/tibia/) and [fibula](https://durgical.com/en/anatomy/fibula/) is the doorway through which the popliteal vessels and tibial nerve enter the deep calf - Mostly slow-twitch, fatigue-resistant fibres: a postural muscle that is active almost all the time in standing ## Key facts **Origin** Posterior head and upper shaft of fibula; soleal line and medial border of tibia; tendinous arch between them **Insertion** Posterior [calcaneus](https://durgical.com/en/anatomy/calcaneus/) via calcaneal (Achilles) tendon **Action** Plantar flexes ankle; steadies leg over foot in standing **Nerve** Tibial nerve (S1–S2) **Blood supply** Posterior tibial, fibular and popliteal (sural) arteries ## Relations **Superficial** Both heads of gastrocnemius, with the [plantaris tendon](https://durgical.com/en/anatomy/tendon-of-plantaris/) running between them **Deep** Deep transverse fascia and, under it, the deep posterior compartment: [tibialis posterior](https://durgical.com/en/anatomy/tibialis-posterior-muscle/), [flexor digitorum longus](https://durgical.com/en/anatomy/flexor-digitorum-longus/), [flexor hallucis longus](https://durgical.com/en/anatomy/flexor-hallucis-longus/), the posterior tibial and fibular vessels and the [tibial nerve](https://durgical.com/en/anatomy/tibial-nerve/) **Above** [Popliteus](https://durgical.com/en/anatomy/popliteus-muscle/) above the soleal line; under its tendinous arch the [popliteal artery](https://durgical.com/en/anatomy/popliteal-artery/) divides and the tibial nerve continues into the leg **Below** Its fibres join the deep surface of the [Achilles tendon](https://durgical.com/en/anatomy/calcaneal-tendon/) lower than those of gastrocnemius, often close to the ankle **Lateral** [Fibularis longus](https://durgical.com/en/anatomy/fibularis-longus-muscle/) and brevis in the lateral compartment, beyond the posterior intermuscular septum ## How to find it Kneeling on a chair with the knee bent and the heel lifted, the soleus is felt as a firm mass on both sides of the lower calf, below and beside the gastrocnemius bellies and on either side of the Achilles tendon. ## Examination - Silfverskiöld test: dorsiflexion limited with the knee both straight and bent points to soleus or Achilles tightness, not gastrocnemius alone - Bent-knee (seated) heel raise: weakness or pain with the knee bent singles out the soleus, as in a soleus strain ## On imaging On ultrasound it is the broad muscle deep to the gastrocnemius. Calf compression ultrasound can include its veins: a soleal vein that does not compress and holds echogenic material means a muscular vein thrombosis. MRI shows strains, often along its aponeurosis. An accessory soleus appears on MRI as a muscle mass in front of the Achilles tendon, filling the fat pad there. ## Clinical notes - Superficial posterior compartment syndrome (gastrocnemius, soleus, [plantaris](https://durgical.com/en/anatomy/plantaris-muscle/)): a tense, painful calf with pain on passive ankle dorsiflexion - The soleus is the classic local muscle flap for defects of the middle third of the tibia (the medial gastrocnemius covers the upper third) - Soleus strains in runners are deeper and come on more gradually than gastrocnemius tears; bent-knee heel raises reproduce the pain - The soleal arch is followed in surgery to find the tibial nerve and posterior tibial vessels as they enter the deep posterior compartment ## Anatomical variants - An accessory soleus can appear as a soft-tissue swelling at the back of the ankle, in front of or beside the Achilles tendon, mimicking a tumour and sometimes causing exertional pain - The arrangement of its fibres varies between people ## Development From the ventral (flexor) muscle mass of the leg; like the gastrocnemius it is supplied by the tibial nerve, mainly through the S1 and S2 roots. ## Memory aid The name comes from Latin solea, a sandal or flat fish: the broad, flat muscle lying under the gastrocnemius. ## Related conditions - [Achilles tendon rupture](https://durgical.com/en/conditions/achilles-tendon-rupture/) - [Medial tibial stress syndrome (shin splints)](https://durgical.com/en/conditions/medial-tibial-stress-syndrome/) ## Test yourself Think of the answer, then tap the question to see it. ## Why does the soleus keep working when the knee is bent? It is a one-joint muscle that does not cross the knee, so it still acts when the gastrocnemius is slack; bent-knee heel raises single it out. ## Why is the soleus linked to deep vein thrombosis? Its venous sinuses drive the calf muscle pump, and deep vein thrombosis often starts in the soleal veins. ## What passes under the tendinous arch of the soleus? The popliteal vessels and the tibial nerve, entering the deep posterior compartment of the calf. ## Which muscle is the classic local flap for defects of the middle third of the tibia? The soleus; the medial gastrocnemius covers the upper third. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/anatomy/soleus-muscle/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** musculus soleus TA2 2660 **Official Spanish (DeCS)** Músculo sóleo **English (TA2)** Soleus muscle ## Related - [Gastrocnemius (inner head)](https://durgical.com/en/anatomy/medial-head-of-gastrocnemius/) - [Tibial nerve](https://durgical.com/en/anatomy/tibial-nerve/) - [Popliteal artery](https://durgical.com/en/anatomy/popliteal-artery/) - [Soleus tendon](https://durgical.com/en/anatomy/tendon-of-soleus/) - [Fibula](https://durgical.com/en/anatomy/fibula/) - [Achilles tendon](https://durgical.com/en/anatomy/calcaneal-tendon/) Sources: Terminologia Anatomica (TA2); [Anatomy, Bony Pelvis and Lower Limb: Calf](https://www.ncbi.nlm.nih.gov/books/NBK459362/); [Anatomy, Bony Pelvis and Lower Limb: Leg Posterior Compartment](https://www.ncbi.nlm.nih.gov/books/NBK537340/). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/soleus-muscle/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/soleus-muscle/