# Problem in segmenting small hand bones

**URL:** <https://discourse.slicer.org/t/problem-in-segmenting-small-hand-bones/29566>\
**Category:** Support\
**Created:** [May 21, 2023, 5:42pm UTC](https://discourse.slicer.org/t/problem-in-segmenting-small-hand-bones/29566 "2023-05-21T17:42:06Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![TewoSpring](https://avatars.discourse-cdn.com/v4/letter/t/71e660/32.png) [@TewoSpring](https://discourse.slicer.org/u/TewoSpring)\
**Post date:** [May 21, 2023, 5:42pm UTC](https://discourse.slicer.org/t/problem-in-segmenting-small-hand-bones/29566/1 "2023-05-21T17:42:06Z")

</div>

Hi! I am new here; also thak you for the support and the developement of Slicer: I am really enjoying it!  
So my problem is with the segmentation of the scaphoid in the RMI.

It seems that, even if I am using the 1% size brush tool, I cannot get the precise shape of the scapoid section. What is also odd is that when I use the draw tool I can draw the exact shape of the bone but then the segmented area is always off (please see the pic attached).

 ![WhatsApp Image 2023-05-20 at 12.38.23](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/4/e/4ea3d4766ef13473d1f4f45f535b4cf52700429a.jpeg)

Is that a problem of volumes?  
What can I do to resolve this?

P.s. also there are any other ortho hand surgeon here?

Thank you

---

<div class="post-metadata">

**Author:** ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Post date:** [May 21, 2023, 5:43pm UTC](https://discourse.slicer.org/t/problem-in-segmenting-small-hand-bones/29566/2 "2023-05-21T17:43:15Z")

</div>

This section of the documentation explains why this happens and what you can do about it: [Segment editor — 3D Slicer documentation](https://slicer.readthedocs.io/en/latest/user_guide/modules/segmenteditor.html#segmentation-is-not-accurate-enough)