Barbed, Bidirectional Surgical Sutures:

1
Barbed, Bi-directional Surgical Sutures
Biomechanical Performance vs. Suture
Geometry Nilesh P. Ingle1
1. Introduction

• Surgical sutures, either braided or monofilament,
  are most commonly used to close wounds and
  approximate tissues. Tying a knot has been the
  primary method to secure sutures.
• Disadvantages of Knotted Sutures
• Delay of wound healing
• Constriction of blood flow
• Distortion of tissue which can lead to scar
  formation
• Loss of knot security due to increased local
  stress concentrations
• Advantages of Barbed Sutures
• Faster placement--eliminates the necessity to
  tie a knot
• Even distribution of holding forces in tissue
• Elimination of complications associated with
  knots, e.g. infection and suture spitting
• Better cosmesis benefits

5. Conclusion
Alpha Stitch

• Monofilament Diameter
• Cut Length
• End to start distance
• Barb Length
• Nose Length
• Distance between barbs
• Barb angle, cdv
• Barb angle, blv
• Cut depth I
• Cut depth II
• Offset angle, K
• Offset angle, N
• Barb base length

• 5.1 The samples from Design A and Design B
  were significantly
• different at a 95 confidence level for
• Cut Angle
• Cut Depth I II
• Cut Length
• Barb Length
• Barb Base Length

Side View

• 5.2 No significant differences were observed
  between
• Design A and Design B for
• Offset Angle, K N
• Barb Angle cut depth view barb length view
• Spiral Angle

Top View
Cut angle
2. Objective
The objective of this study was to investigate
the influence of barb geometry on the sutures
biomechanical performance. This entails
characterization of barb geometry parameters and
measurement of tissue holding capacity in an in
vitro model.
5.3 No significant difference was observed
between the zones within each design
of suture material. This means that the
geometric measurements of all the
barbs within each design fall under a
single population. 5.4 The barbed sutures
with a steeper cut angle and a median cut depth
have a higher tissue holding capacity
than those with a moderate cut angle
and a nominal cut depth.
3. Materials and Methods
4. Results and Discussion
Two different designs of barbed sutures were
fabricated from polydioxanone monofilament, size
0 (0.45 mm diameter). 3.1 Measurement of Barb
Geometry The barb geometries were mapped and
characterized using an Optem Zoom microscope
and Image Analysis Software.
3.2 Tissue Holding Capacity
The cut angle and cut depth of the two designs
were found to be significantly different.
The tissue holding capacity of these barbed
sutures was determined by measuring the peak load
required to separate the wound made in a tissue
simulant and closed with either an alpha or M
stitch.
Acknowledgement Nilesh Ingle wishes to
acknowledge the College of Textiles, North
Carolina State University and Quill Medical, Inc.
for financial support. He also wishes to thank
Dr. Subhash K. Batra, and Dr. Behnam Pourdeyhimi
for guidance, and to Dr. Eunkyoung Shim and Mr.
Chad Graham for assistance with testing.
The barbed suture is divided into two regions,
left and right. Each region contains barbs that
face the other in opposing directions from the
suture mid-point. The barbs are arranged in a
spiral configuration around the length of the
monofilament. The geometry of these barbs can
vary, depending on the pre-determined cut angle
and desired depth.
M Stitch
Cut Depth View
Barb Length View
Significant differences in peak load were
observed between the two different designs of
barbed sutures (Table 2).
Normal Side View (Before Twisting)
Top View
Normal Side View (After Twisting)
Martin W. King,1 Jeffrey C. Leung,2 and Stan
Batchelor,2 1Textile Apparel Technology
Management, North Carolina State University
2Quill Medical, Inc. Research Triangle Park, NC
27713