[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Head and neck](https://durgical.com/en/anatomy/region/head-and-neck/) › Lateral pterygoid [Muscular system](https://durgical.com/en/anatomy/system/muscular-system/) · [Head and neck](https://durgical.com/en/anatomy/region/head-and-neck/) # Lateral pterygoid The lateral pterygoid is a two-headed chewing muscle running forward from the jaw joint; it pulls the jaw forward to open the mouth and moves it sideways. Official name: Superior head of lateral pterygoid muscle [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=head_neck&select=lateral_pterygoid&side=r) Opens in the Durgical app, no sign-up needed. ## What it is A two-headed muscle running forward from the jaw joint to the skull base. ## What it does Pulls the condyle and disc forward to open the jaw and moves it sideways. ## Key points - The only chewing muscle that opens the jaw: it pulls the condyle and the TMJ disc forward onto the articular eminence - With a mandibular nerve lesion the jaw deviates toward the weak side on opening, pushed by the healthy lateral pterygoid - In a condylar neck fracture it pulls the condyle forward and medially ## Key facts **Origin** Superior head: greater wing of the sphenoid; inferior head: lateral surface of the lateral pterygoid plate **Insertion** Neck of the mandibular condyle (pterygoid fovea), TMJ disc and capsule **Action** Protrudes the mandible and opens the jaw (pulls condyle and disc forward); side-to-side movement **Nerve** Nerve to lateral pterygoid (V3) **Blood supply** Pterygoid branches of the maxillary artery ## Relations **Lateral** Ramus and coronoid process of the [mandible](https://durgical.com/en/anatomy/mandible/) and the [temporalis](https://durgical.com/en/anatomy/temporalis-muscle/); the [maxillary artery](https://durgical.com/en/anatomy/maxillary-artery/) usually crosses its lower head **Medial** [Medial pterygoid](https://durgical.com/en/anatomy/medial-pterygoid-muscle/), whose two heads clasp its lower head, the [sphenomandibular ligament](https://durgical.com/en/anatomy/sphenomandibular-ligament/), the mandibular nerve and the [middle meningeal artery](https://durgical.com/en/anatomy/middle-meningeal-artery/) **Above** Infratemporal surface of the greater wing of the [sphenoid bone](https://durgical.com/en/anatomy/sphenoid-bone/), near the [foramen ovale](https://durgical.com/en/anatomy/foramen-ovale/) and [foramen spinosum](https://durgical.com/en/anatomy/foramen-spinosum/) **Contents** The buccal nerve passes between its two heads; the lingual and inferior alveolar nerves appear at its lower border; the pterygoid venous plexus surrounds it **Behind** Condyle, [TMJ capsule](https://durgical.com/en/anatomy/temporomandibular-joint/) and [TMJ disc](https://durgical.com/en/anatomy/articular-disc-of-temporomandibular-joint/), into which its fibres insert ## How to find it Cannot be palpated reliably; intraoral pressure behind the maxillary tuberosity is often described but mostly reaches neighbouring tissue. It is seen on MRI and CT of the infratemporal fossa and met in approaches to the condyle. ## Examination - Opening the mouth and sticking the chin forward against resistance; deviation toward one side on opening suggests weakness of that side's muscle - Moving the jaw side to side: each lateral pterygoid moves the chin to the opposite side ## On imaging TMJ MRI shows its upper head attached to the disc in front of the condyle; it is the key to reading anterior disc displacement on closed- and open-mouth images. ## Clinical notes - Anterior TMJ dislocation: on wide opening the condyle slides in front of the articular eminence and the elevators lock it there; reduction pushes the jaw down and then back - Myofascial pain of this muscle is a common cause of preauricular pain in temporomandibular disorders - In V3 lesions (tumours at the foramen ovale, trauma) jaw deviation on opening is an early, easily missed sign ## Anatomical variants - The maxillary artery runs superficial to the lower head in most people and deep to it in the rest; the share varies between populations - A third head is described in some dissections ## Development First pharyngeal arch muscle, supplied by its own branch of V3. ## Memory aid «Lateral lowers»: the lateral pterygoid opens (lowers) the jaw; the others close it. ## Related conditions - [Temporomandibular disorder](https://durgical.com/en/conditions/temporomandibular-disorder/) ## Test yourself Think of the answer, then tap the question to see it. ## Which is the only chewing muscle that opens the jaw? The lateral pterygoid: it pulls the condyle and the TMJ disc forward onto the articular eminence. ## Which way does the jaw deviate on opening with a mandibular nerve lesion, and why? Toward the weak side, pushed by the healthy lateral pterygoid. ## Where does the lateral pterygoid insert? On the neck of the mandibular condyle (pterygoid fovea), the TMJ disc and capsule. ## In a condylar neck fracture, which way does the lateral pterygoid pull the condyle? Forward and medially. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/anatomy/superior-head-of-lateral-pterygoid-muscle/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** caput superius musculi pterygoidei lateralis TA2 2110 **Official Spanish (DeCS)** Músculo pterigoideo lateral DeCS D011626 **English (TA2)** Superior head of lateral pterygoid muscle **Also called** external pterygoid · upper head of lateral pterygoid muscle · sphenomeniscus muscle ## Related - [TMJ disc](https://durgical.com/en/anatomy/articular-disc-of-temporomandibular-joint/) - [V3 mandibular](https://durgical.com/en/anatomy/anterior-division-of-mandibular-nerve/) - [Maxillary artery](https://durgical.com/en/anatomy/maxillary-artery/) Sources: Terminologia Anatomica (TA2); [DeCS](https://decs.bvsalud.org/es/ths/resource/?id=12061&filter=ths_termall&q=Pterygoid%20Muscles); [Anatomy, Head and Neck, Lateral Pterygoid Muscle](https://www.ncbi.nlm.nih.gov/books/NBK549799/); [Anatomy, Head and Neck, Mastication Muscles](https://www.ncbi.nlm.nih.gov/books/NBK541027/). ## **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-head-of-lateral-pterygoid-muscle/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/superior-head-of-lateral-pterygoid-muscle/