General guide to sutures
For a Resident Beginning Surgery Training
Starting surgical training can feel overwhelming, and sutures are often the first “tools” a resident truly masters. Choosing the right suture, handling it properly, and knowing why you’re using it are as important as knowing how to tie a knot. This guide is designed as a practical, resident-friendly introduction to sutures.
1. What Is a Suture?
A suture is a medical device used to hold tissues together until healing occurs. A complete suture consists of:
Thread (material)
Needle (attached or swaged)
Your goal as a surgeon is secure tissue approximation with minimal trauma and optimal healing.
2. Basic Classification of Sutures
A. Based on Absorbability
Absorbable Sutures
Broken down by the body over time
Used where long-term tensile strength is not required
Common examples
Vicryl (Polyglactin 910)
PDS (Polydioxanone)
Monocryl (Poliglecaprone)
Typical uses
Subcutaneous tissue
Fascia (delayed absorbable like PDS)
Bowel anastomosis
Non-Absorbable Sutures
Remain indefinitely unless removed
Provide long-term strength
Common examples
Silk
Nylon (Ethilon)
Polypropylene (Prolene)
Polyester (Ethibond)
Typical uses
Skin
Vascular anastomosis
Tendon repair
B. Based on Structure
Monofilament
Single smooth strand
Less tissue drag, lower infection risk
More memory → harder to handle
Examples: Prolene, Nylon, PDS
Multifilament (Braided)
Better handling and knot security
More tissue reaction and infection risk
Examples: Silk, Vicryl, Ethibond
3. Suture Size: Understanding the Numbers
Sizes range from 10-0 (finest) to 5 or higher (thickest)
More zeros = thinner suture
Rule of thumb
Use the smallest suture that provides adequate strength
Common choices
Skin: 2-0 or 3-0 Ethilon (Bailey says 4-0, 5-0 in face)
Fascia: 1 or 0 PDS
Bowel: 3-0 Vicryl/PDS
Vessels: 6-0 or 7-0 Prolene
4. Surgical Needles: What Every Resident Must Know
Needle Components
Point
Body
Swage (attachment to suture)
Common Needle Types
Round Body (Tapered)
Spreads tissue rather than cutting
Used for soft tissues
Uses: bowel, muscle, fascia
Cutting Needle
Triangular with cutting edge
Strong penetration
Uses: skin
Reverse Cutting Needle
Cutting edge on the outer curve
Less risk of tissue cut-through
Preferred for skin closure
5. Choosing the Right Suture: Practical Guide
| Tissue | Preferred Suture |
|---|---|
| Skin | Nylon(Ethilon) / Prolene (Vicryl/monocryl if below epidermis) |
| Subcutaneous | Vicryl |
| Fascia | PDS / Prolene |
| Bowel | Vicryl / PDS |
| Vessels | Prolene |
| Tendon | Ethibond |
6. Knot Tying: Fundamentals You Must Master Early
Key Principles
Square knots, not granny knots
Adequate throws (usually 3–5)
Maintain constant tension
Avoid excessive tightening (prevents tissue ischemia)
Common Knots
Instrument tie (most common)
Surgeon’s knot (adds extra throw for tension)
Hand-tie (essential skill—practice daily)
Tip for residents:
Practice knot tying outside the OT every day—shoelaces, ropes, or practice boards.
7. Handling Sutures: Common Beginner Mistakes
❌ Crushing the needle with forceps
❌ Holding needle too close to the swage or tip
❌ Over-tightening knots
❌ Using thick sutures unnecessarily
❌ Excessive tissue handling
✔ Hold needle at ⅔ from the tip
✔ Gentle, precise movements
✔ Respect tissue planes
8. Infection and Tissue Reaction
Monofilament sutures reduce infection risk
Braided sutures harbor bacteria
Silk causes more tissue reaction (still useful but selective)
Golden rule
In contaminated fields, avoid braided sutures when possible
9. Learning Strategy for First-Year Residents
Memorize common suture–tissue combinations
Practice needle handling and knot tying daily
Observe seniors and consultants closely
Ask why a particular suture is chosen
Keep a small notebook of OT learning points
10. Final Take-Home Message
Sutures are not just threads—they are decisions.
Good surgeons:
Choose the right material
Handle tissue atraumatically
Tie secure, well-placed knots
Mastering sutures early builds confidence, improves outcomes, and sets the foundation for your entire surgical career.
Disclaimer
This article is intended for educational purposes only for surgical trainees. Clinical decisions should always be made under senior supervision and institutional protocols