# How does the skull attach to the top of the spine? **URL:** \ **Category:** Factual Questions\ **Created:** [May 8, 2018, 1:06pm UTC](https://boards.straightdope.com/t/how-does-the-skull-attach-to-the-top-of-the-spine/813812 "2018-05-08T13:06:28Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![brujaja](https://avatars.discourse-cdn.com/v4/letter/b/4af34b/32.png) [@brujaja](https://boards.straightdope.com/u/brujaja)\ **Post date:** [May 8, 2018, 1:06pm UTC](https://boards.straightdope.com/t/how-does-the-skull-attach-to-the-top-of-the-spine/813812/1 "2018-05-08T13:06:28Z")
How **does** the skull attach, exactly? Is it, you know, pretty secure? And why would that joint suddenly start clicking whenever I move my head? Seriously. ---
**Author:** ![Nava](https://avatars.discourse-cdn.com/v4/letter/n/da6949/32.png) [@Nava](https://boards.straightdope.com/u/Nava)\ **Post date:** [May 8, 2018, 2:05pm UTC](https://boards.straightdope.com/t/how-does-the-skull-attach-to-the-top-of-the-spine/813812/2 "2018-05-08T14:05:59Z")
I’m sure our docs will come soon and bring better info, but in general it’s the same stuff which keeps any other joint together: mainly the muscles (with some help from the skin). Bunch of explanations on the muscles of the skull and neck [here](http://www.innerbody.com/anatomy/muscular/head-neck). We speak of the “musculoskeletal system”; the muscles move the bones here and there, but also keep them together. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [May 8, 2018, 2:48pm UTC](https://boards.straightdope.com/t/how-does-the-skull-attach-to-the-top-of-the-spine/813812/3 "2018-05-08T14:48:16Z")
There are two special vertebrae at the top of the spine that form the joint with the skull. The atlas is ringlike and holds up the skull. It allows flexion (up and down nodding of the head). The axis, below it, has a projection that essentially forms a ball-and-socket type joint and allows rotation of the head (movement from side to side). [Much more here.](https://www.visiblebody.com/blog/3d-skeletal-system-atlas-axis-and-the-atlanto-axial-relationship) Like the knuckles, the craniospinal joint is a synovial joint, containing lubricating fluid, and so can be [“cracked”](https://en.wikipedia.org/wiki/Cracking_joints) like the knuckles. ---
**Author:** ![Leo\_Bloom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leo_bloom/32/10377_2.png) [@Leo\_Bloom](https://boards.straightdope.com/u/Leo_Bloom)\ **Post date:** [May 8, 2018, 2:51pm UTC](https://boards.straightdope.com/t/how-does-the-skull-attach-to-the-top-of-the-spine/813812/4 "2018-05-08T14:51:33Z")
> [@Colibri](#): > > … [Much more here.](https://www.visiblebody.com/blog/3d-skeletal-system-atlas-axis-and-the-atlanto-axial-relationship) Like the knuckles, the craniospinal joint is a synovial joint, containing lubricating fluid, and so can be [“cracked”](https://en.wikipedia.org/wiki/Cracking_joints) like the knuckles. Superb site/cite. Thanks. ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [May 8, 2018, 3:24pm UTC](https://boards.straightdope.com/t/how-does-the-skull-attach-to-the-top-of-the-spine/813812/5 "2018-05-08T15:24:22Z")
I’ve been hearing sounds in the joint when I move my head for a couple of years, although I’d describe it as crunching rather than clicking. When I described it to my doctor he said it’s a typical sign of bone degeneration in the spine. He recommended I see a posture specialist to help minimize the progress of the degeneration. ---
**Author:** ![phreesh](https://avatars.discourse-cdn.com/v4/letter/p/9fc29f/32.png) [@phreesh](https://boards.straightdope.com/u/phreesh)\ **Post date:** [May 8, 2018, 4:28pm UTC](https://boards.straightdope.com/t/how-does-the-skull-attach-to-the-top-of-the-spine/813812/6 "2018-05-08T16:28:05Z")
‘Posture specialist’. Huh. Is that a medical doctor? Amazing how specialized medicine has become. ---
**Author:** ![brujaja](https://avatars.discourse-cdn.com/v4/letter/b/4af34b/32.png) [@brujaja](https://boards.straightdope.com/u/brujaja)\ **Post date:** [May 8, 2018, 10:51pm UTC](https://boards.straightdope.com/t/how-does-the-skull-attach-to-the-top-of-the-spine/813812/7 "2018-05-08T22:51:42Z")
> [@Colibri](#): > > There are two special vertebrae at the top of the spine that form the joint with the skull. The atlas is ringlike and holds up the skull. It allows flexion (up and down nodding of the head). The axis, below it, has a projection that essentially forms a ball-and-socket type joint and allows rotation of the head (movement from side to side). [Much more here.](https://www.visiblebody.com/blog/3d-skeletal-system-atlas-axis-and-the-atlanto-axial-relationship) Like the knuckles, the craniospinal joint is a synovial joint, containing lubricating fluid, and so can be [“cracked”](https://en.wikipedia.org/wiki/Cracking_joints) like the knuckles. Yes, that is a terrific cite. Thanks! ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [May 9, 2018, 8:35am UTC](https://boards.straightdope.com/t/how-does-the-skull-attach-to-the-top-of-the-spine/813812/8 "2018-05-09T08:35:41Z")
> [@phreesh](#): > > ‘Posture specialist’. Huh. Is that a medical doctor? Around here, they are not medical doctors, but are degreed, certified practiciioners called biokineticists. I understand this is one field where it varies widely worldwide, though.