What is the step by step procedure for the figure of eight (figure 8) suture technique?

Figure-of-Eight Suture Technique: Step-by-Step Procedure

The figure-of-eight suture is a versatile technique that creates two parallel suture lines on one surface with a figure-of-eight pattern on the opposite surface, providing secure tissue approximation through interlocking tension distribution.

Core Principle

The fundamental concept involves creating an interlocking suture pattern that distributes tension across two parallel points while the crossing pattern provides mechanical stability. This technique is particularly effective for stabilizing adjacent cartilage segments, preventing tissue overlap, and achieving hemostasis in vascular access sites 1.

Standard Figure-of-Eight Technique (General Application)

Entry and First Pass

• Position the needle 4-5 mm from the tissue edge and enter vertically through the first tissue layer 2
• Pass the needle through the tissue in a mucosa-to-serosa direction (or equivalent tissue layers depending on anatomical location) 2
• Exit on the opposite side at the same distance from the edge, creating a parallel entry point 2

Return Pass (Creating the "8")

• Bring the needle back to the original entry side at a 45-degree angle 2
• Re-enter the tissue 5 mm below (or adjacent to) the first entry point 2
• Pass horizontally through to exit on the opposite side, completing the figure-of-eight pattern 2

Securing the Suture

• Pull both loose ends to approximate the tissue edges 2
• Tie the knots on the appropriate surface (mucosal surface for internal applications, serosal surface for external applications) 2
• The final appearance shows two parallel suture lines approximately 0.5 mm apart on one surface, with the figure-of-eight pattern visible on the opposite surface 2

Specialized Applications

For Cartilage Stabilization (Rhinoplasty/Nasal Surgery)

• Use the figure-of-eight suture to stabilize adjacent cartilage segments after realignment procedures 1
• This prevents overlap of cartilage fragments following weakening procedures such as castellation or complete incisions 1
• The interlocking pattern provides superior stability compared to simple interrupted sutures 1

For Venous Hemostasis (Large-Bore Access)

• Insert the needle approximately 1 cm lateral to the puncture site at the level of the femoral vein 3, 4
• Pass through subcutaneous tissue and superficial fascia without entering the vessel 3
• Cross over the puncture site and exit 1 cm on the opposite side 3
• Return the needle back across the puncture site in a figure-of-eight pattern 3
• Apply controlled tension to achieve hemostasis without completely occluding the vessel 3, 4
• A torque device can be applied to manage variable suture tension instead of tying a permanent knot, allowing easy adjustment and removal 4

For Vertical Mattress Applications (Ophthalmologic Surgery)

• The figure-of-eight vertical mattress technique allows simultaneous closure of two tissue layers (anterior mucosal flaps and overlying wound tissues) 5
• Enter deep tissue first, then return through superficial layers in the figure-of-eight pattern 5
• Tie knots completely outside the wound, avoiding the disadvantages of suture tying in small, deep areas 5
• This eliminates dead space between tissue layers and prevents collapse of anterior structures 5

Critical Technical Points

Suture Material Selection

• Use monofilament sutures for most applications to reduce infection risk and tissue drag 1
• For cartilage stabilization, 5-0 nylon or 4-0 PDS are appropriate 1
• For venous closure, use non-absorbable monofilament sutures that can be removed after hemostasis is achieved 3, 4
• For internal tissue approximation, slowly absorbable sutures (6-0) are preferred 1

Tension Management

• Distribute tension evenly across both parallel suture lines to prevent tissue ischemia 2
• Avoid excessive tightening that could compromise blood supply or cause tissue necrosis 3, 4
• The figure-of-eight pattern inherently distributes force more evenly than simple interrupted sutures 5, 2

Common Pitfalls and How to Avoid Them

Incorrect Spacing

• Maintain consistent 4-5 mm distances from tissue edges to prevent tearing or inadequate approximation 2
• Keep parallel suture lines 0.5 mm apart for optimal mechanical advantage 2

Suture Sliding in Comminuted Tissue

• For comminuted fractures or fragmented tissue, enclose a small plate or rigid structure within the suture loop to prevent the suture from sliding into fracture lines 6
• This modification maintains compression across multiple fragments 6

Vascular Complications

• When using for venous hemostasis, avoid entering the vessel lumen 3
• Monitor for signs of venous occlusion (leg swelling, discoloration) if tension is too tight 3
• The technique achieved 98.7% hemostasis success with only 1.3% vascular complications in a large series 3

Nerve Entrapment

• Place sutures over bony support rather than soft tissue alone to avoid nerve compression 1
• Avoid excessive depth when passing through tissue layers to prevent inadvertent nerve capture 7

Advantages Over Alternative Techniques

• Faster closure time compared to multiple interrupted sutures (mean 38.2 minutes vs longer conventional techniques) 5
• Simultaneous two-layer closure reduces operative steps 5
• Superior mechanical stability through interlocking tension distribution 2, 6
• Lower complication rates (1.3% vs 6.8% with manual compression for venous access) 3
• Eliminates dead space between tissue layers 5
• Allows for adjustable tension when modified with torque device 4