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IN A NUTSHELL
Brett Moreira, MD
Melbourne, AUSTRALIA
Suturing Material–Knot vs Knotless for Wound Closure
In wound closure, suture materials come as braided or monofilament, absorbable or non-absorbable. Absorbable sutures, such as monofilament have shown less infections in contaminated wounds than braided sutures with several studies showing bacteria adhering more tightly to the braided suture. Monofilament sutures cause less reaction than do braided sutures, but require more ties to ensure an adequate knot compared to braided suture. Braided suture usually incites a larger inflammatory response but requires fewer ties to maintain the knot integrity.
Another option is a barbed bidirectional monofilament suture, which has permits knotless wound closure. The barbs allow the suture to distribute tension across the length of the wound without the need for knots. The bidirectionality allows for two surgeons to work simultaneously to close a wound.
Barbed monofilament suture is being used more frequently as a result of this efficiency and cost savings. Studies using barbed monofilament suture have shown decreased operative time and decreased costs to theatre with wound strength and tissue reaction scores comparable to those of monofilament suture tied with knots.
It is believed that knotting the suture can exaggerate the physical characteristics of the monofilament or braided suture causing inflammatory reactions. Therefore, a barbed suture that does not require knots may be less likely to provoke an inflammatory cascade.
Barbed sutures possess a theoretical advantage over traditional running monofilament sutures in the event of a suture rupture or failure. The barbs should theoretically resist a catastrophic failure of the entire length of the suture by holding the suture in place, even if one site breaks.
Overall, the presence of barbs is yet to be shown in the literature to prevent wound dehiscence over monofilament sutures. Currently, the bacterial properties of barbed monofilament suture, such as bacterial adherence and correlation with postoperative wound infection, have not been defined in comparison to standard monofilament and braided sutures.
What is Pulsatile Lavage?
Is the old orthopaedic phrase correct, that ‘the solution to pollution is dilution’. We recognize the theoretical basis for irrigation to dilute contamination and non-viable tissue and that a greater volume of irrigation would be expected to achieve greater dilution. A decrease in wound infection is proportional to the amount of irrigation used. At least 5 liters of pulsatile lavage is required to ensure removal of more than 95% of the debris.
Irrigation has evolved from the use of a continuous stream of fluid to the use of discrete pulses of fluid, produced at a frequency of approximately 1,200 pulses / min (20 Hz), delivered to the required site. Pulsed or pulsatile lavage is a mechanical form of hydrotherapy and was originally used by oral surgeons at Walter Reed Medical Centre during the Vietnam War. It was used to rapidly irrigate grossly contaminated wounds to reduce wound related sepsis and delayed wound healing.
Today, its use has progressed part of standard of care for irrigating open fractures and contaminated wounds. In total joint arthroplasty, the role of pulse lavage is to help clean and improve the bone surface preparation, leaving a coralline structure that allows for better compression of the cement in the bone.
40 ISAKOS NEWSLETTER 2015: Volume I