In surgical sutures, the terms reverse cutting, round body, and sizes like 2/0, 3/0, 3 refer to specific characteristics of the suture needle and the thread. Here’s what they mean:
1. Reverse Cutting Needle
- Shape: Has a triangular cross-section with a cutting edge on the outer curve of the needle.
- Purpose: Designed to penetrate tough tissues like skin, oral mucosa, or tendons without tearing.
- Advantage: Stronger than conventional cutting needles and reduces the risk of cutting through tissue.
2. Round Body (Taper Point) Needle
- Shape: Smooth, rounded cross-section without cutting edges.
- Purpose: Used for soft, delicate tissues like muscle, peritoneum, fat, and internal organs.
- Advantage: Gently spreads tissue without cutting, minimizing trauma.
3. Suture Sizes (e.g., 2/0, 3/0, 3)
Suture sizes indicate the diameter (thickness) of the thread. Two systems are commonly used:
a. United States Pharmacopeia (USP) system (common in many countries):
- Sizes go from very fine to thick like this:
- 5-0 (00000): very thin (used for delicate work like facial or vascular surgery)
- 3-0 (000): slightly thicker
- 2-0 (00): thicker still
- 0 (0): medium
- 1, 2, 3: increasing thickness, with 3 being quite thick (used in orthopedic or fascia closure)
Examples:
| Size | Thickness | Typical Use |
|---|---|---|
| 3-0 | Fine | Skin on face, small vessels |
| 2-0 | Medium | General skin closure, muscle |
| 3 | Thick | Orthopedic, tendon or fascia closure |
The more zeros, the finer the suture. E.g., 5-0 is thinner than 3-0.
Summary
| Term | Meaning |
|---|---|
| Reverse Cutting | Needle with outer cutting edge, for tough tissue like skin |
| Round Body | Needle with smooth, non-cutting edge, for soft tissue |
| 2/0 or 2-0 | Medium-thin suture thread |
| 3/0 or 3-0 | Thinner than 2-0 |
| 3 | Much thicker, used for strong tissue closure |
