What is the difference between a single stitch and a continuous stitch in surgical closures?

Continuous vs. Interrupted Sutures: Key Differences and Clinical Implications

For surgical wound closure, continuous sutures are preferred over interrupted sutures because they reduce superficial wound dehiscence by 92% (RR 0.08; 95% CI 0.02-0.35), require less operative time, and show no difference in infection rates or incisional hernia formation. 1

Technical Differences

Continuous Suture Technique

• A single running thread closes the entire wound length without interruption, typically placed subcuticularly using absorbable monofilament material 1
• Creates a continuous seal along the wound edge that may better prevent bacterial invasion 1
• Distributes tension evenly across the entire wound length, reducing risk of tissue ischemia at individual stitch points 2
• Does not require removal when absorbable materials (4-0 poliglecaprone or 4-0 polyglactin) are used, which retain 50-75% tensile strength after 1 week 1, 3

Interrupted Suture Technique

• Individual stitches placed separately along the wound, each tied independently 1
• Typically uses non-absorbable transcutaneous sutures that require removal at 7-9 days postoperatively 1
• Allows selective removal of individual problematic stitches without compromising the entire closure 4
• Takes significantly longer to perform compared to continuous technique 1

Clinical Outcomes: What the Evidence Shows

Wound Dehiscence

• Superficial wound dehiscence occurs in only 3.7% of patients overall, but 22 of 23 cases occurred in the interrupted suture group 1, 4
• The dramatic reduction with continuous sutures (RR 0.08) is likely due to prolonged wound support from absorbable material that doesn't require removal 1, 4

Surgical Site Infection

• No significant difference in SSI rates between techniques (RR 0.73; 95% CI 0.40-1.33) 1
• Overall SSI rate is 6.5% regardless of suture technique used 4

Incisional Hernia and Fascial Closure

• For fascial closure specifically, no difference exists between continuous and interrupted techniques in terms of incisional hernia or dehiscence 1
• The suture-to-wound length ratio of at least 4:1 is more important than whether the technique is continuous or interrupted 1

Operative Time

• Continuous closure is faster, which is particularly valuable in emergency surgery settings where operative time directly impacts patient outcomes 1

Optimal Technique Recommendations

For Skin Closure

• Use continuous subcuticular technique with slowly absorbable monofilament sutures (4-0 poliglecaprone or polyglactin) 1, 3
• Avoid interrupted transcutaneous non-absorbable sutures that require removal, as this timing coincides with peak dehiscence risk 1, 4

For Fascial Closure in Emergency Laparotomy

• Either technique is acceptable for fascial closure, but continuous is preferred due to time savings 1
• Maintain 4:1 suture-to-wound length ratio regardless of technique chosen 1
• Use "small bite" technique (5mm from wound edge, 5mm between bites) including only aponeurosis 3, 5
• Choose slowly absorbable monofilament material to reduce pain and maintain strength 1

For Contaminated Fields

• Use triclosan-coated antimicrobial sutures (OR 0.72; 95% CI 0.59-0.88 for SSI reduction) regardless of continuous vs. interrupted technique 3, 6

Critical Pitfalls to Avoid

• Never use rapidly absorbable sutures for fascial closure, as they increase incisional hernia rates 1, 3
• Avoid removing non-absorbable sutures before 7-9 days for most surgical wounds, as premature removal causes dehiscence 1, 7, 6
• Don't use continuous sutures that are pulled too tightly, as this strangulates wound edges and causes ischemia 1
• Never leave retained suture material, particularly superficial or exposed fragments, as this significantly increases infection risk 7, 6
• Avoid interrupted non-absorbable transcutaneous sutures for skin closure when continuous subcuticular absorbable sutures are available 1, 3, 4

When Interrupted Sutures May Be Preferred

• High-tension wounds where individual stitch adjustment is needed for optimal approximation 3
• Situations requiring selective stitch removal due to localized complications without compromising entire closure 4
• Facial wounds where 5-0 or 6-0 monofilament non-absorbable interrupted sutures allow precise cosmetic closure 7