Wound closure

I’m Dr. Ryan Nunley in St. Louis, Missouri. I’m a practicing orthopaedic surgeon who takes care of predominately hip and knee replacement patients. My practice ranges from simple primaries to advanced revisions, and I also treat a significant number of infections that are referred in from outside communities.

I think that wound closure may be the most important step in total joint procedures to prevent drainage and infection in order to protect our expensive implants. I’m passionate about wound closure because I think that any amount of drainage is the surgeon’s fault. Either we didn’t optimize the patient well before surgery or we didn’t achieve good hemostasis in wound closure after surgery. I take a lot of pride in making sure our wounds heal well so that we don’t have complications.

Drainage to me is disaster because any amount of drainage creates a potential for the outside world to get on the inside. For example, bending or extending the knee can create a suction phenomenon where any fluid that comes out will egress as the knee changes direction. This creates the potential for bacteria on the skin surface to get inside the incision through weak spots in the arthrotomy closure and colonize the implant.

Several studies have shown that patients who have a wound that drains have a substantially increased risk of developing deep infection. Infection is one of the worst outcomes a patient can have after a knee or hip replacement, so avoiding drainage helps to minimize the risk of infection.

Drainage is multifactorial and there’s not one specific reason why a person drains. I believe that drainage is caused by lack of attention to detail during closure. Our biggest challenge is caused by the traditional use of interrupted sutures to close the arthrotomy and the skin. Whenever you have an interrupted suture there will be a weak spot between each sequential suture. This means that when the knee is bent following surgery, synovial fluid and any hemarthrosis will look for the path of least resistance and percolate through the interrupted sutures.

In terms of my workflow, I prefer barb sutures that are watertight and can hold a significant amount of tension. This creates a continuous line of force so there is no specific weak point. It is important to minimize the amount of ooze while getting good hemostasis and achieving a watertight seal during closure.

I break the knee wound closure down into four parts and each part has a separate suture. The first part is the arthrotomy realignment where I want to make sure the arthrotomy is lined up perfectly. At the beginning of each case I make three hash marks for the first suture, which is #1 Vicryl, where I place three interrupted stitches to get the arthrotomy properly lined up.

The second part of the wound closure is the actual arthrotomy and creating that watertight seal. That’s a barbed #1 PDS Stratafix suture that we wrap up from the bottom to the top to create that watertight closure.

The third part is what I call the adipose tissue and deep dermal layer where we want to get the soft tissue close but not completely close and allow that to divide the tension and stress along the deeper layers. We also close down the dead space created between the arthrotomy and the skin with a #1 PDS Stratafix running barb suture.

The final closure will be subcuticular, so I’ll use a monofilament Monocryl. It has two needles that allow surgeon and assistant to close in different directions and it’s a knotless system, so it creates a watertight seal. That’s the third watertight seal of the four-part process.

I want to make sure that the arthrotomy is appropriately reapproximated because an arthrotomy that is closed where it’s off alignment can affect the patellofemoral tracking. At the beginning of a surgery before we make the arthrotomy, I use a marking pen to create three lines that will help us at closure. The first stitch I use is an interrupted #1 Vicryl and I use it in three spots where those three original marks were to get the arthrotomy reapproximated and ensure the tissue is in the right position.

To create my first watertight seal of the arthrotomy, I use the barbed #1 PDS Stratafix suture, running it from the bottom and overlap it. I start two centimeters above the distal aspect of the arthrotomy, go distally three or four passes, and then come back up proximally. When I get to the top the suture will come back on itself. It’s a knotless system that gets tight from sequentially pulling, and you have to backtrack a couple of throws to lock it into position.

It’s the most important seal because the intraarticular space is where we have exposed the bone and stretched and cut into the soft tissue. It is where we’re going to get the most ooze hematoma, hemarthrosis and synovial fluid within a few hours of surgery. When a patient starts bending the knee, that bend creates a fluid dynamic pressure that builds up over the front of the knee where the arthrotomy closure is. That’s the first watertight closure.

For the second watertight closure, I use the #1 PDS Stratafix running barbed suture to come back through the deep dermal layer, which is a little bit deeper than the subcuticular layer. In very obese patients I incorporate some of the adipose tissue. I start two or three inches proximal to the inferior aspect of the incision, go down and then come back up to the top. Once I get to the top, I will use the remaining barb suture strand to come almost halfway back down again. The second watertight closure of the deep dermal layer helps with cosmesis of the incision. When you have little tension on the incision you get a very nice and thin incision compared to staples or some of the other closures where there may be some gapping.

My last suture is a running subcuticular, which essentially becomes the third watertight seal for the incision. I use a barbed Monocryl suture that goes in both directions. This allows a surgeon and assistant to suture at the same time to speed up the closure. Then I cover the area with Prineo, which is an adhesive skin glue to create a barrier from the outside world, allowing patients to shower with minimal need for additional dressing changes.

I think wound closure is extremely important, whether it’s the deep arthrotomy closure, the intermediate layers with the adipose and the deep dermal, or the subcuticular. If you use the wrong suture at any of those stages or if you don’t have your watertight closure, there is propensity for drainage. Drainage is a down slope effect of infections, return visits to the emergency room and calls to the office. There are a number of patient satisfaction and clinical outcomes that become more problematic if you have drainage.

It’s well known in the literature that wound closure goes through several phases. The hemostatic phase usually occurs within the first 7 to 14 days when bleeding into the soft tissue starts to become more organized, creating the early scaffold for collagen fibers to align. The scaffold becomes more organized and dense during the proliferative phase. After about three months the maturation phase begins, which can take about a year to complete. That’s why the incision of a knee wound is warm for about a year while the incision itself tends to go from a deeper purple to a light pink to white over that time period.

Watertight closure is important, not only for drainage but also to ensure that tissue can go through the phases of wound healing. If you have tissue that moves and separates, the amount of collagen that needs to be laid down to create a natural barrier becomes greater and that gap distance takes longer to heal in. Having a watertight closure allows the tissue to stay in close contact to become more efficient in terms or reorganization of the collagen fibers.

Figuring out techniques that are more universally applicable to all assistants in the O.R. who are closing the wounds is important. Knots can be variable and interrupted sutures take time. There is an increased risk of infection with every minute in the O.R. The best thing we can do is use more knotless sutures with the barb technology for a watertight closure. With a more efficient closure there is less time the wound is open to the air, less drainage, potentially less hematoma, less seroma and less potential for infection. In the event of wound breakdown or an entry point, sutures coated with an antimicrobial agent could also help to avoid an infection. I would say that the skill level of the person closing the wound and the type of suture material they use can also affect wound healing to minimize drainage and infection.

I’ve used the product for eight years and have not seen any drainage that I could relate to STIMULAN. I’m so compulsive about my wound closure that I don’t want to see drainage on any patient, whether it’s with or without STIMULAN. It’s achieving that watertight closure that is adequate to sustain the forces of physical therapy, the seromas, the hematomas, the normal synovial fluid that develop after we do a surgery, to make sure that we get no drainage.

It makes sense that as STIMULAN dissolves, there is a natural elution process which could create some additional substance that gets mixed into the synovial fluid or seroma. I intentionally place STIMULAN below the arthrotomy because I think that is the most robust closure. I never put STIMULAN above the arthrotomy and want it deep. I want to keep it in place by creating a watertight barrier with a barbed running suture to have enough tension, so that fluid dynamics associated with knee motion don’t push any of the extra fluid with the now dissolving STIMULAN up through the arthrotomy. I think that if you keep STIMULAN inside the arthrotomy, it never gets to the adipose or the dermal side and you won’t have drainage issues.