[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Spine](https://durgical.com/en/anatomy/region/spine/) › T3–T4 disc [Joints and ligaments](https://durgical.com/en/anatomy/system/joints-and-ligaments/) · [Spine](https://durgical.com/en/anatomy/region/spine/) # T3–T4 disc The T3-T4 disc is the thin cushion between the T3 and T4 vertebrae in the mid-back; it allows the small movement the [ribs](https://durgical.com/en/anatomy/ribs/) permit. Official name: T3-T4 [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=spine&select=disc_t3_t4&side=r) Opens in the Durgical app, no sign-up needed. ## What it is The cushion between T3 and T4: a tough outer ring of fibres (annulus fibrosus) around a soft centre. ## What it does Absorbs load and allows the small amount of movement the rib cage permits. ## Key points - Upper edge of the mid-thoracic watershed (about T4–T9): few feeding arteries reach the cord and the canal is at its tightest around the cord, so compression here is poorly tolerated - A lateral herniation irritates the T3 root, a band around the upper [chest](https://durgical.com/en/anatomy/region/chest/) just below the armpit ## Key facts **Where** Between T3 and T4 bodies; thin thoracic disc; head of rib 4 joins it **Attaches** Annulus fibrosus anchored to the [endplates](https://durgical.com/en/anatomy/vertebral-endplates/) and ring apophyses of T3 and T4; anterior and posterior longitudinal ligaments **Function** Absorbs and spreads load; herniation rare, often central onto the cord; lateral herniation may irritate the T3 root ## Relations **In front** [Esophagus](https://durgical.com/en/anatomy/esophagus-abdominal-part/) and [trachea](https://durgical.com/en/anatomy/trachea/) just above the tracheal bifurcation; the [aortic arch](https://durgical.com/en/anatomy/aortic-arch/) curves backward on the left side of T4 **Lateral** Head of rib 4 on the disc and its costovertebral joint, with the [sympathetic trunk](https://durgical.com/en/anatomy/sympathetic-trunk/) over the rib heads **Behind** [Posterior longitudinal ligament](https://durgical.com/en/anatomy/posterior-longitudinal-ligament/) and the [spinal cord](https://durgical.com/en/anatomy/spinal-cord/), with little spare room in the canal ## How to find it With the arms at the sides, the root of the scapular [spine](https://durgical.com/en/anatomy/region/spine/) lies at about the T3 spinous process; the disc sits deep, in front of the canal, at roughly the height of that tip. ## On imaging On sagittal T2 MRI the bright rim of fluid in front of the cord is thin at T3–T4, so a protrusion that wipes it out touches the cord. Small thoracic protrusions are frequent in people without symptoms, so the image is read together with the examination. ## Common problems - Thoracic disc herniations are uncommon; many are found by chance on MRI and cause no symptoms. - A large one can press on the spinal cord, or cause band-like pain around the chest. ## How it is diagnosed MRI; CT shows whether the herniation is calcified (hardened), which matters for surgery. ## Treatment - Usually physical therapy and pain medicine; surgery only if the spinal cord is pressed. ## Clinical notes - Upper thoracic disc pain can imitate angina; a cardiac cause is usually excluded first - A posterolateral route (transpedicular or costotransversectomy) suits a lateral disc at this height; a central or calcified one may need a transthoracic view of its front ## Test yourself Think of the answer, then tap the question to see it. ## Why is cord compression at the T3–T4 disc poorly tolerated? It is the upper edge of the mid-thoracic watershed (about T4–T9): few feeding arteries reach the cord and the canal is tight around it. ## Which heart condition can upper thoracic disc pain at T3–T4 imitate? Angina, so a cardiac cause is usually excluded first. ## Which rib head joins the T3–T4 disc? The head of rib 4, with its costovertebral joint; the sympathetic trunk lies over the rib heads. [Add to my cards (3)](https://durgical.app/estudiar/?add=/en/anatomy/t3-t4/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** discus intervertebralis T3-T4 TA2 1684 **Official Spanish (DeCS)** Disco T3-T4 DeCS D007403 **English (TA2)** T3-T4 **Also called** fibrous ring · fibrocartilago intervertebralis ## Related - [T3–T4 nucleus](https://durgical.com/en/anatomy/t3-t4-spine-and-pelvis/) - [T3 vertebra](https://durgical.com/en/anatomy/t3/) - [T4 vertebra](https://durgical.com/en/anatomy/t4/) Sources: Terminologia Anatomica (TA2); [DeCS](https://decs.bvsalud.org/es/ths/resource/?id=7567); [Anatomy, Back, Intervertebral Discs](https://www.ncbi.nlm.nih.gov/books/NBK470583/); [7.3 The Vertebral Column](https://openstax.org/books/anatomy-and-physiology-2e/pages/7-3-the-vertebral-column) (OpenStax (Rice University), 2022) · adapted, [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/). ## **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/t3-t4/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/t3-t4/