[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/) › T1–T2 disc [Joints and ligaments](https://durgical.com/en/anatomy/system/joints-and-ligaments/) · [Spine](https://durgical.com/en/anatomy/region/spine/) # T1–T2 disc The T1-T2 disc is the thin cushion between the T1 and T2 vertebrae in the mid-back; it allows the small movement the [ribs](https://durgical.com/en/anatomy/ribs/) permit. Official name: T1-T2 [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=spine&select=disc_t1_t2&side=r) Opens in the Durgical app, no sign-up needed. ## What it is The cushion between T1 and T2: 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 - The T1 root leaves through the T1–T2 foramen, so a lateral herniation here can weaken the small muscles of the hand, unlike lower thoracic discs that give only a band of [chest](https://durgical.com/en/anatomy/region/chest/) pain - The T1 root also carries the sympathetic fibres bound for the head and eye; compressing it can add a same-side Horner syndrome (small pupil, drooping lid) - Cervicothoracic junction: the head of rib 2 sits on this disc, and the stiff rib-bearing [spine](https://durgical.com/en/anatomy/region/spine/) meets the mobile neck just above ## Key facts **Where** Between T1 and T2 bodies; thin thoracic disc; head of rib 2 joins it **Attaches** Annulus fibrosus anchored to the [endplates](https://durgical.com/en/anatomy/vertebral-endplates/) and ring apophyses of T1 and T2; anterior and posterior longitudinal ligaments **Function** Absorbs and spreads load; herniation rare, often central onto the cord; lateral herniation may irritate the T1 root ## Relations **In front** [Longus colli](https://durgical.com/en/anatomy/longus-colli-muscle/), then the [esophagus](https://durgical.com/en/anatomy/esophagus-abdominal-part/) with the [trachea](https://durgical.com/en/anatomy/trachea/) in front of it; the great vessels lie further forward, and the [thoracic aorta](https://durgical.com/en/anatomy/thoracic-aorta/) does not reach this height **Lateral** Head of rib 2 and its costovertebral joint; the [sympathetic trunk](https://durgical.com/en/anatomy/sympathetic-trunk/), with the cervicothoracic (stellate) ganglion just above on the neck of rib 1; the T1 root rising over rib 1 to join the [brachial plexus](https://durgical.com/en/anatomy/roots-of-brachial-plexus/) **Behind** [Posterior longitudinal ligament](https://durgical.com/en/anatomy/posterior-longitudinal-ligament/), the epidural space and the [spinal cord](https://durgical.com/en/anatomy/spinal-cord/) ## How to find it Not palpable. The next spinous process below the [vertebra prominens](https://durgical.com/en/anatomy/vertebra-prominens/) (C7) is T1; the disc lies deep, at about the height of the T1 tip, behind the top of the chest. ## Examination - Resisted finger abduction (interossei) tests the C8–T1 myotome; isolated weakness with a same-side Horner syndrome points to the T1 root ## On imaging The shoulders hide this level on a plain lateral radiograph (a swimmer's view or CT helps); sagittal MRI shows it well, and counting down from C2 confirms the level. ## 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 - Hand-intrinsic weakness with a Horner syndrome also fits a lung apex (Pancoast) tumour or a lower brachial plexus lesion, which are ruled out before blaming the disc - Hard to reach from the front behind the [sternum](https://durgical.com/en/anatomy/sternum/) and great vessels; a posterolateral route or an extended low cervical approach is used instead - The sympathetic trunk and the stellate ganglion lie on the rib necks just beside this disc; a lateral or anterior approach can injure them and leave a Horner syndrome ## Development The annulus forms from sclerotome cells gathered around the notochord, while the notochord trapped between two developing bodies swells into the nucleus. ## Test yourself Think of the answer, then tap the question to see it. ## Which root leaves at the T1–T2 disc, and how does a lateral herniation here differ from lower thoracic discs? The T1 root; it can weaken the small muscles of the hand, while lower thoracic discs give only a band of chest pain. ## Why can compression of the T1 root at the T1–T2 disc add a Horner syndrome? The T1 root carries the sympathetic fibres for the head and eye, giving a same-side small pupil and drooping lid. ## Which rib head sits on the T1–T2 disc? The head of rib 2, with its costovertebral joint. [Add to my cards (3)](https://durgical.app/estudiar/?add=/en/anatomy/t1-t2/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** discus intervertebralis T1-T2 TA2 1684 **Official Spanish (DeCS)** Disco T1-T2 DeCS D007403 **English (TA2)** T1-T2 **Also called** fibrous ring · fibrocartilago intervertebralis ## Related - [T1–T2 nucleus](https://durgical.com/en/anatomy/t1-t2-spine-and-pelvis/) - [T1 vertebra](https://durgical.com/en/anatomy/t1/) - [T2 vertebra](https://durgical.com/en/anatomy/t2/) 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/); [7.5 Embryonic Development of the Axial Skeleton](https://openstax.org/books/anatomy-and-physiology-2e/pages/7-5-embryonic-development-of-the-axial-skeleton) (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/t1-t2/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/t1-t2/