[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/) › Tibialis posterior tendon [Muscular system](https://durgical.com/en/anatomy/system/muscular-system/) · [Lower limb](https://durgical.com/en/anatomy/region/lower-limb/) # Tibialis posterior tendon The tibialis posterior tendon runs behind the inner ankle bone to the navicular bone; it is a key support of the foot's arch. Official name: Tendon of tibialis posterior [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=lower_limb&select=tibialis_posterior_tendon&side=r) Opens in the Durgical app, no sign-up needed. ## What it is The tendon of the [tibialis posterior](https://durgical.com/en/anatomy/tibialis-posterior-muscle/). It runs behind the inner ankle bone and fans out under the foot, mainly onto the navicular. ## What it does Holds up the inner arch and turns the foot inward. It helps you rise onto your toes. ## Key points - Degeneration and rupture usually occur just behind and below the medial malleolus, a relatively poorly supplied zone where the tendon turns - When it fails, the spring ligament stretches and the foot flattens; early stages are flexible, later ones fixed, and the ankle may finally tilt into valgus - An accessory navicular within its insertion can cause medial foot pain and weaken the tendon's pull ## Key facts **Attaches** Most anterior tendon behind the medial malleolus, under the flexor retinaculum; mainly to the navicular tuberosity and [medial cuneiform](https://durgical.com/en/anatomy/medial-cuneiform-bone/), with slips to the other tarsals (not the [talus](https://durgical.com/en/anatomy/talus/)) and the bases of metatarsals 2–4 **Function** Inversion and plantarflexion; the main dynamic support of the medial longitudinal arch; its failure causes adult-acquired flatfoot **Tight in** Eversion with dorsiflexion ## Relations **Course** Deep in the back of the leg, it passes under the [flexor digitorum longus](https://durgical.com/en/anatomy/flexor-digitorum-longus/) above the ankle (crural chiasm), then lies in a groove behind the medial malleolus and runs forward under the flexor retinaculum to the [navicular](https://durgical.com/en/anatomy/navicular-bone/) tuberosity **Behind** Flexor digitorum longus tendon, then the [posterior tibial artery](https://durgical.com/en/anatomy/posterior-tibial-artery/) and veins and the [tibial nerve](https://durgical.com/en/anatomy/tibial-nerve/) **Deep** Medial malleolus, [deltoid ligament](https://durgical.com/en/anatomy/medial-collateral-ligament-of-ankle/) and the [spring ligament](https://durgical.com/en/anatomy/plantar-calcaneonavicular-ligament/), which it covers on its way to the navicular **Superficial** Flexor retinaculum, the roof of the tarsal tunnel ## How to find it With the foot pointed down and turned in against resistance, the tendon is felt just behind and below the medial malleolus and traced forward to the navicular tuberosity, the bony bump in front of and below the malleolus. ## Examination - Single-leg heel rise: inability to rise, or a heel that does not swing into varus, points to dysfunction - 'Too many toes' sign: seen from behind, more lateral toes show beside the heel on the affected side, from forefoot abduction - Resisted inversion with the foot pointed down: pain or weakness along the tendon ## On imaging Standing radiographs show the flatfoot: an uncovered talar head, a broken line between the talus and the [first metatarsal](https://durgical.com/en/anatomy/first/), and a low calcaneal pitch; ultrasound or MRI show tenosynovitis, thickening, split tears or rupture. ## Common problems - Tendon dysfunction: the tendon becomes inflamed, stretched or torn, usually in middle-aged adults. It is the most common cause of adult-acquired flatfoot. - Pain and swelling along the inner ankle, and trouble standing on tiptoe. - Rarely, a sudden tear or the tendon slipping out of its groove. ## How it is diagnosed A physical exam, including a single heel rise; standing X-rays; MRI or ultrasound of the tendon. ## Treatment - Rest, a boot or brace, arch supports and physical therapy. - Surgery to clean or repair the tendon, often with a transfer of a nearby toe-flexor tendon and bone cuts to realign the foot. - Advanced, stiff flatfoot: fusion of the joints of the back of the foot. ## Clinical notes - Transfer of the flexor digitorum longus to the navicular, often with a medial shift of the [calcaneus](https://durgical.com/en/anatomy/calcaneus/) (osteotomy), replaces the failed tendon in a flexible flatfoot - Tenosynovitis of this tendon can be an early sign of an inflammatory arthritis - A painful accessory navicular can be removed with reattachment of the tendon to the navicular (Kidner procedure) ## Anatomical variants - The insertion may be one broad tendon or split into three bands (main, plantar and recurrent) - An accessory navicular in the tendon is found in a minority of feet ## Development An accessory navicular arises from a separate ossification centre at the navicular tuberosity that does not fuse; it usually becomes noticeable around adolescence, when it may start to hurt. ## Memory aid Behind the medial malleolus, front to back: 'Tom, Dick And Very Nervous Harry' (Tibialis posterior, flexor Digitorum longus, Artery, Vein, Nerve, [flexor Hallucis longus](https://durgical.com/en/anatomy/flexor-hallucis-longus/)). ## Test yourself Think of the answer, then tap the question to see it. ## Which tendon dysfunction is the most common cause of adult-acquired flatfoot? Tibialis posterior tendon dysfunction: the main dynamic support of the medial longitudinal arch fails. ## Where does the tibialis posterior tendon usually degenerate and rupture? Just behind and below the medial malleolus, a relatively poorly supplied zone where the tendon turns. ## What is the 'too many toes' sign? Seen from behind, more lateral toes show beside the heel on the affected side, from forefoot abduction in tibialis posterior dysfunction. ## What is the order of structures behind the medial malleolus from front to back? Tibialis posterior, flexor digitorum longus, artery, vein, nerve, flexor hallucis longus ('Tom, Dick And Very Nervous Harry'). ## Which tendon is transferred to replace a failed tibialis posterior tendon? The flexor digitorum longus, moved to the navicular, often with a medial shift of the calcaneus. [Add to my cards (5)](https://durgical.app/estudiar/?add=/en/anatomy/tendon-of-tibialis-posterior/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** musculus tibialis posterior TA2 2666 **Official Spanish (DeCS)** Tendón del tibial posterior DeCS D013710 **English (TA2)** Tendon of tibialis posterior ## Related - [Deltoid ligament](https://durgical.com/en/anatomy/medial-collateral-ligament-of-ankle/) - [Spring ligament](https://durgical.com/en/anatomy/plantar-calcaneonavicular-ligament/) - [Flexor retinaculum](https://durgical.com/en/anatomy/flexor-retinaculum-of-ankle/) - [Ankle tendon sheaths](https://durgical.com/en/anatomy/anterior-tarsal-tendon-sheaths/) - [Tibialis posterior](https://durgical.com/en/anatomy/tibialis-posterior-muscle/) - [Intermediate cuneiform](https://durgical.com/en/anatomy/intermediate-cuneiform-bone/) - [Lateral cuneiform](https://durgical.com/en/anatomy/lateral-cuneiform-bone/) - [Medial cuneiform](https://durgical.com/en/anatomy/medial-cuneiform-bone/) Sources: Terminologia Anatomica (TA2); [DeCS](https://decs.bvsalud.org/es/ths/resource/?id=14088); [Anatomy, Bony Pelvis and Lower Limb: Tibialis Posterior Muscle](https://www.ncbi.nlm.nih.gov/books/NBK539913/). ## **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/tendon-of-tibialis-posterior/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/tendon-of-tibialis-posterior/