Surgical needle curvature classification
Suture needles are classified by their curvature in fractions of a circle — straight, 1/4 (90°), 3/8 (135°), 1/2 (180°), and 5/8 — which determines the hand's turning radius when passing the needle through tissue.
How it is used
The instrumentista selects curvature based on how confined and deep the surgical field is: tighter curves (1/2, 5/8) for narrow/deep spaces, open curves (1/4, 3/8) for superficial or wide-access fields.
Clinical tip
3/8 and 1/2 circle curvatures are the most commonly used in general surgery, while 5/8 is reserved for confined spaces such as urology or the pelvis.
Sources
This entry is part of the Instriq catalog, researched and written per specialty from real web research -- never generated or invented without verification -- and reviewed skeptically and independently before publication. How this catalog is written.
Image: Wellcome Collection, Wikimedia Commons. License CC BY 4.0. View original source.
History
Added to the catalog on 2026-10-17.
Dates derived from the project's public version-control history on GitHub, not a live collaborative edit log.