[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/) › Extensor retinacula [Muscular system](https://durgical.com/en/anatomy/system/muscular-system/) · [Lower limb](https://durgical.com/en/anatomy/region/lower-limb/) # Extensor retinacula The extensor retinacula are bands across the front of the ankle that hold the front tendons close to the bone. Official name: Superior extensor retinaculum of ankle [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=lower_limb&select=extensor_retinacula&side=r) Opens in the Durgical app, no sign-up needed. ## What it is Two bands across the front of the ankle: one above the joint and a Y-shaped one below it. ## What it does Hold the front tendons close to the bones so they pull efficiently when the ankle bends. ## Key points - The inferior [extensor retinaculum](https://durgical.com/en/anatomy/extensor-retinaculum-of-the-wrist/) is Y-shaped: its stem anchors in the sinus tarsi and [calcaneus](https://durgical.com/en/anatomy/calcaneus/), an [upper limb](https://durgical.com/en/anatomy/region/upper-limb/) reaches the medial malleolus and a [lower limb](https://durgical.com/en/anatomy/region/lower-limb/) blends with the [plantar fascia](https://durgical.com/en/anatomy/plantar-aponeurosis/) - Anterior tarsal tunnel: the deep fibular nerve can be compressed under the inferior retinaculum, giving numbness in the first web space - The inferior retinaculum is used to reinforce lateral ankle ligament repairs ## Key facts **Attaches** Superior: anterior borders of [tibia](https://durgical.com/en/anatomy/tibia/) and [fibula](https://durgical.com/en/anatomy/fibula/) above ankle; inferior (Y-shaped): calcaneus to medial malleolus and plantar fascia **Function** Hold [tibialis anterior](https://durgical.com/en/anatomy/tibialis-anterior-muscle/), EHL, EDL and fibularis tertius tendons to ankle; prevent bowstringing ## Relations **Contents** Medial to lateral: [tibialis anterior tendon](https://durgical.com/en/anatomy/tendon-of-tibialis-anterior/), [extensor hallucis longus](https://durgical.com/en/anatomy/extensor-hallucis-longus/), [anterior tibial artery](https://durgical.com/en/anatomy/anterior-tibial-artery/) (becoming the [dorsalis pedis artery](https://durgical.com/en/anatomy/dorsalis-pedis-artery/)) with its veins and the [deep fibular nerve](https://durgical.com/en/anatomy/deep-fibular-nerve/), [toe extensor tendons](https://durgical.com/en/anatomy/tendons-of-extensor-digitorum-longus/) and [fibularis tertius](https://durgical.com/en/anatomy/fibularis-tertius-muscle/) **Superficial** Branches of the [superficial fibular nerve](https://durgical.com/en/anatomy/superficial-fibular-nerve/) crossing over them; medially, the [great saphenous vein](https://durgical.com/en/anatomy/great-saphenous-vein/) and [saphenous nerve](https://durgical.com/en/anatomy/saphenous-nerve/) in front of the medial malleolus **Deep** Ankle [joint capsule](https://durgical.com/en/anatomy/articular-capsule-of-knee-joint/), talar neck and the tendon sheaths **Lateral** The stem of the inferior retinaculum anchors in the sinus tarsi and continues into the inferior fibular retinaculum ## How to find it The superior band lies a few centimetres above the ankle joint line between the tibia and fibula; the inferior band crosses the front of the ankle and top of the [talus](https://durgical.com/en/anatomy/talus/). When the foot and toes are lifted, the tendons bulge between and beyond the bands. ## Examination - Tinel sign over the deep fibular nerve under the inferior retinaculum: tingling into the first web space suggests anterior tarsal tunnel syndrome ## On imaging Ultrasound and MRI show the superior and inferior extensor retinacula as thin dark bands across the [extensor tendons](https://durgical.com/en/anatomy/extensor-digitorum-tendons/) in front of the ankle. Look for thickening or a tear after a sprain and sheath fluid beneath. In anterior tarsal tunnel syndrome, imaging looks for what presses on the deep fibular nerve, such as a dorsal talonavicular osteophyte or a ganglion; radiographs show the spurs. ## Common problems - Tight shoes or laces over the lower band can press on the deep fibular nerve (anterior tarsal tunnel). ## Clinical notes - Anterior tarsal tunnel syndrome: numbness in the first web space and, in long-standing cases, wasting of the [extensor digitorum brevis](https://durgical.com/en/anatomy/extensor-digitorum-brevis/); causes include tight laces, osteophytes and ganglia - If the retinaculum is torn or released, the tibialis anterior tendon can bowstring across the front of the ankle - Anterior ankle arthroscopy portals sit medial to the tibialis anterior and lateral to the fibularis tertius; the lateral portal is close to the superficial fibular nerve ## Anatomical variants - Some texts describe an extra upper-lateral band of the inferior retinaculum, so that it looks X-shaped rather than Y-shaped ## Memory aid Under the extensor retinacula, medial to lateral: "The Hospitals Are Not Dirty Places" (Tibialis anterior, Hallucis longus, Artery, Nerve, Digitorum longus, Peroneus tertius). ## Test yourself Think of the answer, then tap the question to see it. ## What is the shape of the inferior extensor retinaculum, and where are its limbs attached? Y-shaped: the stem anchors in the sinus tarsi and calcaneus, an upper limb reaches the medial malleolus and a lower limb blends with the plantar fascia. ## What is anterior tarsal tunnel syndrome? Compression of the deep fibular nerve under the inferior extensor retinaculum, giving numbness in the first web space. ## What happens to the tibialis anterior tendon if the extensor retinaculum is torn or released? It can bowstring across the front of the ankle. ## Which nerve is close to the lateral portal of anterior ankle arthroscopy? The superficial fibular nerve; the lateral portal sits lateral to the fibularis tertius. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/anatomy/superior-extensor-retinaculum-of-ankle/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** retinaculum extensorium superius tali; retinaculum extensorium inferius tali TA2 2712 **Official Spanish (DeCS)** Retináculos extensores superior e inferior del tobillo **English (TA2)** Superior extensor retinaculum of ankle **Also called** transverse crural ligament · cruciate crural ligament · ligamentum transversum cruris ## Related - [Tibialis anterior tendon](https://durgical.com/en/anatomy/tendon-of-tibialis-anterior/) - [Toe extensor tendon](https://durgical.com/en/anatomy/tendon-of-extensor-digitorum-longus/) - [Extensor hallucis longus](https://durgical.com/en/anatomy/extensor-hallucis-longus/) - [Deep fibular nerve](https://durgical.com/en/anatomy/deep-fibular-nerve/) - [Crural fascia](https://durgical.com/en/anatomy/crural-fascia/) - [Fibula](https://durgical.com/en/anatomy/fibula/) - [Tibia](https://durgical.com/en/anatomy/tibia/) Sources: Terminologia Anatomica (TA2); [Anatomy, Bony Pelvis and Lower Limb: Leg Anterior Compartment](https://www.ncbi.nlm.nih.gov/books/NBK539725/). ## **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/superior-extensor-retinaculum-of-ankle/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/superior-extensor-retinaculum-of-ankle/