Published 1/1/2014
Terry Stanton

Study: Barbed Sutures Show Advantages in TKA

Multicenter randomized clinical trial demonstrates shorter closure time, lower cost

“As orthopaedic surgeons, we are all aware of the need for improved operating room efficiency, better resource allocation, and increased patient and surgeon safety,” said Jeremy M. Gililland, MD, in introducing his study on the use of barbed sutures in total knee arthroplasty (TKA) during the 2013 annual meeting of the American Association of Hip and Knee Surgeons.

For their prospective study comparing the use of barbed sutures with standard knotted sutures in TKA, the investigators hypothesized that multilayered closure in TKA with barbed sutures would be associated with the following:

  • shorter closure times
  • lower costs
  • similar closure-related perioperative complication rates
  • similar Knee Society, cosmesis, and patient satisfaction scores

The analysis group consisted of 394 knees in 363 patients. Randomization occurred in the operating room, and patients were blinded to the technique used in their knee closure. Barbed sutures were used in 191 knees, and standard sutures in 203 knees. Surgeries were performed at four institutions.

Faster closure
Closure time for the barbed suture study group was significantly shorter (P < 0.001) at a mean of 9.8 minutes, compared with the closure time of 14.4 minutes for knotted sutures. The mean closure cost was also significantly lower (P < 0.001) in the barbed group than the standard group—$324 versus $419.

Intraoperatively the barbed group had 12 broken sutures, compared with none in the control group (P < 0.001). However, needle stick injuries to surgical staff were higher in the control group; this difference was not significant.

No significant differences were seen in major or minor complications between the groups. This finding extended to rates of wound infection, which were further analyzed at 2 and 6 weeks postoperatively. Skin closure was not associated with the cosmesis score.

Cellulitis was analyzed to assess for associations between the study group and dermal closure, ASA score, and smoking; no correlation was found at 6 weeks after surgery.

In surgery, the control group patients underwent a two-layer closure with a standard interrupted, knotted suture technique. All closures were performed by two members of the surgical team (with no medical students participating) to limit the possible confounding factor of closure time variation. The medial parapatellar approach was used in all cases.

The study group underwent a two-layer closure utilizing barbed suture with a running, knotless technique, consisting of an arthrotomy closure and a subdermal closure, each performed with a running baseball stitch. This study technique used a bidirectional barbed suture with a needle on each end; the barbs change direction at the midpoint allowing unidirectional passing in opposite directions from the midpoint out, thus creating oppositional traction when engaged.

For the arthrotomy, the suture was passed through both sides of the arthrotomy at its midpoint with the lengths equalized (Fig. 1). This allowed both ends to be simultaneously run in opposing direction; after several throws the suture was cinched to approximate the incision and engage the barbs in each direction. At the end of the incision, the suture direction was reversed for several throws to further anchor the ends by engaging additional barbs. The suture ends were then cut without tying knots. This same procedure was used for the subdermal closure (Fig. 2).

At the completion of subdermal closure, the closure clock was stopped and the time of closure was recorded prior to the final skin closure. The final skin closure method, determined by the attending surgeon, was collected for analysis and included a combination of subdermal sutures, staples, butterfly stitches, and/or topical skin adhesive. Each of the surgeons and their surgical teams had experience using both control and study techniques for multilayered closure in TKA, Dr. Gililland said.

Knotty issues
Interrupted knotted sutures that have traditionally been used for TKA closures have several potential disadvantages, Dr. Gililland said. “Knots are time-consuming to tie, and needle handling during knot tying may predispose the surgeon to inherent risk. Additionally, knots may place uneven pressure on tissue, leading to ischemia, while the absorption of bulky knots may cause local tissue inflammation and scarring and cause a potential nidus for infection.”

Occasionally, the authors of the paper noted, “sutures extrude through skin weeks after surgery, allowing a potential pathway for infection. In contrast, barbed sutures do not require knots due to their self-anchoring nature.” Another advantage of barbed sutures is more uniform tissue tension, lowering the risk for local tissue ischemia. Finally, Dr. Gililland said, “The speed of closure is improved with barbed sutures, which may increase operative day efficiency and productivity.”

The authors noted several limitations to their study, including its focus on TKA, the fact that not all surgeons used the same superficial skin closure technique, and the inability to determine a statistically significant difference between groups in rates of complications and needle sticks, due to the size of the study.

Dr. Gilliland noted that the positive experience and improved efficiency with the barbed method has led to more widespread use at the institutions involved in this study. The authors concluded, “Further studies are needed to determine the safety and effectiveness of the widespread use of barbed suture in the multilayered closure of revision arthroplasty and general orthopaedics.”

Coauthors with Dr. Gililland are Lucas Anderson, MD; Jacob Barney, BS; Hunter L. Ross, BS; Christopher E. Pelt, MD; and Christopher L. Peters, MD.

Disclosure information: Dr. Gililland—Angiotech; Dr. Pelt—Biomet; Dr. Peters—Biomet, Journal of Arthroplasty, AAHKS. Dr. Anderson, Mr. Barney, and Mr. Ross reported no conflicts. Research funding for this study was provided by Angiotech, the manufacturer of Quill sutures.

Terry Stanton is a senior science writer for AAOS Now. He can be reached at tstanton@aaos.org

Bottom Line

  • A previous small trial indicated that use of barbed sutures in total knee and hip arthroplasty may yield shorter closure times.
  • This industry-sponsored multicenter, randomized, controlled clinical trial focused on TKA found significantly shorter closure times and significantly lower costs with the use of barbed sutures compared with standard knotted sutures.
  • A two-layer closure was used in both the control (standard, interrupted, knotted suture technique) and barbed (running knotless technique) suture groups to close the arthrotomy and the subcutaneous layer.
  • Further studies should investigate whether barbed sutures have an advantage in total hip arthroplasty and other procedures.