Table of Contents
Pilonidal disease is a chronic skin and subcutaneous infection emanating from the center of the natal cleft, often extending to the buttocks. It is more common in males than females and usually occurs between the time of puberty and 40 years of age. A common theory is that pilonidal disease is caused by an ingrown hair at the center of the cleft resulting in inflammation and infection extending to the buttocks. Presentation of the pilonidal disease can range from an asymptomatic cyst, or midline pits to chronically inflamed cyst, large open wounds in the midline, long draining sinus tract, or an acute abscess. Only in exceptionally rare cases is imaging required. Treatment depends on the disease pattern. An acute abscess is treated with drainage and antibiotics, while a complex or recurring infection is treated surgically with either excision of a cyst or unroofing of a sinus tract. Reconstructive flap techniques such as the Bascom cleft lift procedure, Karydakis flap, rhomboid, or Z-plasty can be done to reduce the risk of recurrence by leaving less scar tissue and flattening the region between the buttocks. Recent data has suggested that off-midline incision closure may lead to a lower risk of recurrence.1 Here, we present the case of a male patient who had previously had flap surgery for the pilonidal disease, but experienced recurrence and the development of a sinus tract. Due to the extensive nature of the disease, a deep flap was required to mobilize tissues and close the eventual wound. A deep flap like this is often only required in re-do surgery, rather than for primary disease, which a 1cm subcutaneous flap only is required
Pilonidal disease, coming from the Latin “pilus” meaning “hair” and “nidus” meaning “nest,” is characterized as the presence of sinus tracts or natal cleft “pits.” Thought initially to be a hereditary disease, it is now recognized as being secondary to hair follicle obstruction and subsequent cyst formation and possible rupture with the creation of sinus tracts or abscesses. Although first described in the 1800s, much of the initially reported data on the disease came during World War II, when close to 80,000 U.S. soldiers were treated for the disease. Termed “Jeep riders’ disease,” surgical treatment was associated with dramatically poor outcomes and led to the historically favorable conservative approach. In a cohort study over 17 years, only 23 out of 150 cases (approximately 15%) required an operation, and for those presenting with an acute abscess, over 60% of patients can be managed with simple incision and drainage.2 Almost exclusively presenting initially in young adults, males preferentially over females, it has a calculated incidence of 26 per 100,000 individuals.3 Approaches to treatment vary considerably, leading to an associated inconsistency in outcomes and recurrence rates that range from 0–46% when considering all techniques together.4
Our patient presented with the recurrent pilonidal disease after having received a described cleft-lift procedure at another facility. Postoperatively, he developed an early recurrence with an associated long sinus tract. Only patients that fail conservative treatment are referred for surgery. Patients are instructed to use hibiclens solution to wash the cleft in the shower daily and perform hair removal in the cleft twice per month. Typically, at least 3 months of non-operative treatment is required prior to scheduling surgery in order to insure that patients are compliant with the conservative treatment, and to see if conservative treatment fails.
A pre-op physical exam is performed two weeks prior to the scheduled surgery date to ensure there is no acute infection. The patients are typically evaluated at least 2 times over a period of at least 3 months to see if surgery is really warranted and to rule out other conditions such as Crohn’s disease or hidradenitis suppurativa. At the time of examination, shaving of the hair around the gluteal cleft should be performed and patients should be provided with antibacterial soap to be used daily.
Typically, a history and physical examination together are sufficient for the diagnosis of a pilonidal cyst, without the need for additional imaging or laboratory evaluation.
For patients with asymptomatic disease, observation with shaving and attention to hygiene alone is sufficient as most patients will not experience disease progression. Symptomatic disease, however, may be classified and treated according to the level of tissue involvement. Those with acute pilonidal abscess may be initially treated with simple incision and drainage with healing by secondary intention. Patients with recurrent infections are considered for a definitive operation in the future if failing medical therapy. For more complex disease, including patients with sinus tracts, drainage, or recurrence, surgical excision with off-midline closure should be offered if medical therapy fails. Medical therapy includes local hygiene with hibiclens and hair removal, as well as one or more courses of broad spectrum antibiotics such as Augmentin.
Options for treatment are numerous and controversial, leading many surgeons who are less familiar with pilonidal disease to defer to old or outdated techniques. Broad categories for treatment include excision with open healing, midline closure techniques, off-midline closures, and limited excisions. In addition, novel, minimally invasive approaches have begun to emerge as alternatives to traditional surgical treatment.
Excision with open healing by secondary intention is the most common approach and is often studied in counterpart with excision and primary closure.5 Although healing rates are faster with primary closure, the risk of recurrence also increases.
Midline, primary closure involves a complete excision with primary closure with the goal of accelerating wound healing. This approach, however, is plagued by wound dehiscence, recurrence, and infection, most likely due to the high degree of tension placed on the wound with activation of the gluteal muscles and an environment favorable for bacterial growth. As such, there is most likely little to no place for this technique with the advancement of off midline flap closures.6
Off-midline closures of flap techniques other than primary closure, helping to treat disease by flattening the gluteal cleft and reducing hair accumulation and irritation, can be performed via a variety of techniques, including the Karydakis flap, Limberg, Bascom cleft lift, and V-Y advancement flap. A review article from 2010 by Humphries et. al. in Surgical Clinics of North America offers a technical review of the different approaches and interested readers are encouraged to refer to this article for more detail.7 Briefly, the different approaches are largely comparable, and selection be influenced mostly by surgeon preference and experience; although, the Limberg and Karydakis flaps remain the most studied to date.
Limited excision techniques have shown promise as having low morbidity with acceptable recurrence rates and cosmesis. As opposed to incision and drainage, excision of the entire sinus or deroofing and curettage without complete excision may be an excellent option for patients with limited disease, but as with simple excision, the main drawback to this approach is delayed wound healing with secondary intention.8
Finally, while not completely studied, novel techniques such as fibrin glue, phenol treatment, endoscopic approaches, pit picking, and negative pressures dressings show promise.9-12 For patients unable or unwilling to tolerate an operation, or those looking for a rapid return-to-work time, these approaches may become more relevant as more data emerges. Also, while data is limited, many of these techniques report 80–85% cure rate. Of the 15% that fail, a cleft lift is indicated. The author has noted a pattern in their own practice that long term disease management is often achieved through non invasive means in 85% of our patients.
Treatment for pilonidal disease centers around symptom management and psychosocial considerations pertinent to the young demographic most often affected. The morbidity associated with pain and lower quality of life must be balanced against other quality of life measures relevant for this group as well, including return-to-work times, pain associated with the operation itself, time to wound healing, risk of recurrence requiring intervention, and risk for complications.8 Consideration of these factors may alter treatment approach, as different approaches offer a spectrum of risks vs. benefits as described above. For patients presenting acutely with an abscess, incision and drainage is all that is needed to achieve a recurrence-free outcome in close to 60% of patients and is primarily intended to reduce pain and risk of sepsis.13
Patients with recurrent disease after surgical treatment are the most likely to require a complex, flap-based reconstruction and should be referred to a specialist who is familiar with treating recurrent disease.
Here we present the case of recurrent pilonidal disease treated with a Bascom cleft lift procedure.
The goal of this procedure is to remove all of the diseased tissue and obliterate the cleft with an off-midline flap creation. Prior to incision, a local anesthetic is injected surrounding the operative field and an elliptical incision is made. The incision comes as close to midline as possible on the affected side and carries out laterally on the affected side in order to encompass all of the diseased tissue. For this particular procedure, the midline incision was moved slightly laterally in anticipation of scar tissue being present and interfering with the dissection. Hemostasis is critical throughout the entire procedure, as the highly vascular and inflamed tissue here increases the risk for hematoma formation and subsequent infection.
The dissection skews towards the affected side, and pattern recognition here is key in terms of identifying a color change from healthy, yellow fat to diseased, purple, or brown tissue. It is essential to remove all of the diseased tissue while ensuring that enough healthy tissue is left behind to facilitate wound healing.
After removal of the diseased tissue, the dissection continues down to the gluteus maximus muscle for fascial release and flap creation in this particular patient, with recurrent disease. Again, for this highly vascular area, meticulous hemostasis is critical for the prevention of postoperative hematoma. If a fascial release is not enough to maximize tension reduction or pull the flap over, skin or subcutaneous fat flaps can also be created to close the flap and minimize tension. As a general rule, a 5cm release is adequate, but experience and intraoperative evaluation will, of course, dictate minor alterations or adjustments to ensure adequate flap coverage and tension release. In order to reduce tension, often, a 2-3 cm full thickness fasciocutaneous release is required on the unaffected side in order to close the wound. While this reduces tension, it also brings the incision close to midline. The surgeon must take care to do as little mobilization as possible on the unaffected side, while still minimizing tension. The fascial release observed here is, notably, not a traditionally included technical component of the Bascom cleft lift operation and may be considered unnecessary by some surgeons.
Prior to initiation of closing, in our practice, a 10-Blake drain is placed in the newly created potential space which will typically be removed between day 5–10. The closure occurs in five layers, beginning with a deep layer involving the deep fat and any released, intact fascia using a 2-0 polydioxanone (PDS) suture to take advantage of monofilament’s reduction in infection risk. Once the initial layer has been brought together and the tension is reduced, the second layer of PDS suture is used in the deep layer to reinforce and further elevate and bring the incision off the midline. Thorough execution, when approximating this deep layer, is of utmost importance in order to fully lift and obliterate the cleft. The deep layer is then followed by a layer of 2-0 Vicryl in the deep dermis, paying close attention to the caudal end of the cleft lift. 3-0 Vicryl on a small needle is used to reapproximate the dermis that is not perfectly aligned with the 2-0 Vicryl. The sutures are cut short to minimize “spitting” from the incision. The final layer of closure is a 3-0 Monocryl for complete approximation and tension reduction.
The wound is dressed in Steri-Strips and padded with gauze and fluffed dressings. The patient is instructed to take sponge-baths only and to leave the dressings and drain in place until the first appointment 5–6 days after surgery. Until this visit, the patient is instructed not to place any pressure on the wound other than when using the bathroom. The drain is typically removed when the drainage is serous and less than 30cc per day.
The Monocryl stitches are removed at the two-week postoperative visit, and the patient is shaved of all hair in the surrounding area, which is a critical component of keeping the wound clean and free from recurrence. At the one-month postoperative visit, patients are allowed to resume all normal activities without restrictions if the wound has healed appropriately. It is anticipated that approximately 80-85% of patients will progress without any complications whatsoever, and 10-15% of patients will have some minor wound opening that can be managed in the office. Follow-up visits will continue at the three-month, six-month, and one-year mark, after which the patient can be discharged. The specifics of postoperative and preoperative care here, however, are largely based on the experience and opinion of the operating surgeon, and therefore may be controversial among some surgeons.
No special equipment was used for this operation.
Nothing to disclose.
The patient referred to in this video article has given their informed consent to be filmed and is aware that information and images will be published online.
- Berthier C, Berard E, Meresse T, Grolleau JL, Herlin C, Chaput B. A comparison of flap reconstruction vs the laying open technique or excision and direct suture for pilonidal sinus disease: A meta-analysis of randomised studies. Int Wound J. 2019;16(5):1119-1135.
- Armstrong JH, Barcia PJ. Pilonidal sinus disease. The conservative approach. Arch Surg. 1994;129(9):914-917; discussion 917-919. DOI: 10.1001/archsurg.1994.01420330028006
- Sondenaa K, Andersen E, Nesvik I, Soreide JA. Patient characteristics and symptoms in chronic pilonidal sinus disease. Int J Colorectal Dis. 1995;10(1):39-42. DOI: 10.1007/BF00337585
- Hull TL, Wu J. Pilonidal disease. Surg Clin North Am. 2002;82(6):1169-1185. DOI: 10.1016/s0039-6109(02)00062-2
- da Silva JH. Pilonidal cyst: cause and treatment. Diseases of the colon and rectum. 2000;43(8):1146-1156. DOI: 10.1007/BF02236564
- Loganathan A, Arsalani Zadeh R, Hartley J. Pilonidal disease: time to reevaluate a common pain in the rear! Diseases of the colon and rectum. 2012;55(4):491-493. DOI: 10.1097/DCR.0b013e31823fe06c
- Humphries AE, Duncan JE. Evaluation and management of pilonidal disease. Surg Clin North Am. 2010;90(1):113-124, Table of Contents. DOI: 10.1016/j.suc.2009.09.006
- Vartanian E, Gould DJ, Lee SW, Patel KM. Pilonidal Disease: Classic and Contemporary Concepts for Surgical Management. Ann Plast Surg. 2018;81(6):e12-e19. DOI: 10.1097/SAP.0000000000001585
- Kayaalp C, Ertugrul I, Tolan K, Sumer F. Fibrin sealant use in pilonidal sinus: Systematic review. World J Gastrointest Surg. 2016;8(3):266-273. DOI: 10.4240/wjgs.v8.i3.266
- Dogru O, Camci C, Aygen E, Girgin M, Topuz O. Pilonidal sinus treated with crystallized phenol: an eight-year experience. Diseases of the colon and rectum. 2004;47(11):1934-1938. DOI: 10.1007/s10350-004-0720-y
- Milone M, Fernandez LM, Musella M, Milone F. Safety and Efficacy of Minimally Invasive Video-Assisted Ablation of Pilonidal Sinus: A Randomized Clinical Trial. JAMA Surg. 2016;151(6):547-553. DOI: 10.1001/jamasurg.2015.5233
- Ehrl D, Choplain C, Heidekrueger P, Erne HC, Rau HG, Broer PN. Treatment Options for Pilonidal Disease. Am Surg. 2017;83(5):453-457. PMID: 28541853.
- Jensen SL, Harling H. Prognosis after simple incision and drainage for a first-episode acute pilonidal abscess. Br J Surg. 1988;75(1):60-61. DOI: 10.1002/bjs.1800750122
Table of Contents
- Inject Local Anesthesia
- Superficial Incision with No. 15 Blade
- Use Cautery to Excise Cyst and Sinus Tract
- Mobilize Left Gluteal Flap
- Mobilize Right Gluteal Flap
- Mark Subcutaneous Fat for Sutures
- Insert 10 fr Blake Drain
- Suture 1st Deep Fascia Layer with 2-0 PDS
- Suture 2nd Deep Fascia Layer with 2-0 PDS
- Suture Subcutaneous Layer with 2-0 Vicryl
- Suture Subcutaneous Layer with 3-0 Vicryl
- Suture Dermis with 3-0 Monocryl
My name is Michael Reinhorn. I am a surgeon. I specialize in pilonidal surgery. I'm in private practice in a group called Newton-Wellesley surgeons. We work out of Newton-Wellesley Hospital. Today, I'm going to describe the steps of the pilonidal cleft lift procedure. It's a procedure first described by John Bascom in Oregon, and we've modified it a little bit to - to suit our technical skill as well as working with plastic surgeons, specifically on how to best do this for recurrent disease.
So really the - the first step of any procedure is the patient selection, and in this particular case, we had a patient who had a similar type procedure that was described as a cleft lift in an outside hospital. He had a fairly early recurrence and developed a long sinus tract. People with sinus tract are really the best patients to have this procedure because we can improve their quality of life the most.
Once we've decided on surgery, the patients are brought into the office two weeks before surgery to make sure there's no infection. We start them on antibiotics. They wash their skin with Hibiclens soap daily in the shower, and we shave them as well at two weeks before surgery. When they do come in for the day of surgery, they're given a dose of IV antibiotics. Typically, it's broad-spectrum - something like Cipro Flagyl or Unasyn if the patient doesn't have a significant allergy. The patient is always prone, and we retract the gluteal skin to expose the cleft the best way we can. The patient is then marked.
The incision is always created so there is a - as close to an ellipse as possible, and the ellipse is always staggered off the midline so that the final product will be an incision that's off midline. If the diseases to the right, then you lift and skive to the right. If the deli - disease is to the left, obviously, the ellipse would go to the left side. The most medial part of the ellipse is on the side away from the disease, so in this particular patient, did is - the incision was to the right. The left part of the incision was very close to midline. In this case, there is a scar there, so we extended the incision somewhat toward the left side. In someone who's never had surgery before, the incision is always almost at midline.
So once we mark the incision, the next step is giving local anesthetic to reduce the patient's postoperative pain. Although we cut a lot of nerve endings, this can be a painful procedure, and giving local anesthetic ahead of time will reduce the postoperative pain medications for the patient. In fact, we give only 6 to 10 tablets of opioids for this procedure, and most of our patients don't take all of them. The incision is always made with a 15 blade. Just for precision, we use a needle tip cautery for precision to get into the subcutaneous tissues, and then we excise the cyst, basically looking for the area of disease. So we want to leave normal fat behind, and then we want to remove the infected tissue, which is typically either purple or brown in color. In this case, you can see that the tissue is a little bit white because there's some scar there.
Once the cyst is removed, we - we wash and irrigate the area out with an antibiotic solution, and we obtain hemostasis - then develop our flaps. If the incision is off the right, which it was in this particular patient, we create a large flap on the left. We dissect all the way down to the gluteus maximus, taking the gluteal fat pad off either the fascia or taking fascia with us for at least 5 centimeters circumferentially on - on the side that we're mobilizing over. On the opposite side, we mobilize about 2 to 3 centimeters of fat off the gluteus muscle, oftentimes taking fascia with us to allow for flexibility and mobilization.
Once that component is done, we're aggressive with the hemostasis. We then mark a 1 centimeter circle all the way around in the subcutaneous fat - just deep to the dermis - and that's going to be our target to bring the affected side - the unaffected side to the affected side. The approximation is done after we put a jay - a drain in. Typically, we use a Blake drain. Oftentimes, it's a 10 Blake drain. If there's a lot of infection, we will put a 15 Blake drain. We try to minimize the drain size because the bigger the drain, the more output there will be and the longer the drain will have to stay in. We feel that sometimes a drain actually creates some of the - the longer drainage times.
In terms of bringing the flaps together, we use a 2-0 PDS suture. There's a lot of sutures in two layers for the fat pad, and that's done to try to bury the sutures and minimize the tension on the wound. The deep dermal layer, which is next, is typically done with Vicryl suture, so it doesn't spit out from the skin and then the patient can't feel it. That's really one of the more important layers to just approximate the skin edges together. We then use a 3-0 vicryl to - to fine-tune things and then a 3-0 Monocryl to really seal the - the skin edges together. That Monocryl suture we actually remove at 2 weeks postop. Then we'll - lots of fluff dressings are placed on it to protect the wound, and the patient's instructed not to sit down directly on the wound for 7 days except to go to the bathroom.
We're just going to prep. We use iodine just because you don't want alcohol getting on mucous membranes, and we're right near the anus here. So, I guess we've already taped the glutes and retracted them. So he's already had surgery before here that's failed. Somebody attempted or did the same procedure we're doing now, so I'm going to be a little more extensive and go a little bit deeper to mobilize the gluteal fat pad to close this up. So thankfully, his disease is not too low. I put a drape right over the anus. If the disease is a lot lower, we would have a hard time closing this. And then the flaps go out pretty wide, so it's a pretty wide field, and the drapes easily fall off, so I use these 1000 Drapes to kind of hold our towels in place. Before I started using this, at the end when we're closing, I would be staring at the tape and never thought that that was really good for sterility though. We have pus in the wound since this is a chronic infection, so this is considered an infected or dirty field. We still want to minimize any contamination.
Alright, so he's - so this is known as a cleft lift, and he's had this procedure done. It's at the midline, but it's recurred. There's some holes deep down here that we need to excise. Those are the lower pits. So the lower part of our incision is going to encompass those. We need to take out all of the disease. The tricky part is we want to excise enough and move things over, and so, I think here the goal is so that the incision will be off the midline and that the cleft will be obliterated. So he had pretty deep cleft. We're going to have to mobilize a little bit of this side to release some of the tension. We don't want to release too much. Sorry, this is the site we're going to release more on. So we do want to release quite a bit to move it over, and then on this side, we're just going to release a little bit of the tension - and we'll go as wide as we need to.
So we'll give some local on a periphery to - to block the pain response ahead of time. So we typically give 40 cc's of local just to get started, and then I'll put some in the drain at the very end. So what - we will drain this wound because it's considered dirty. So I'm just going to confirm that what I marked looks okay. We're going to take out all the disease, which is the - the sinus opening. These all connect. I don't feel like we need to do more than this - do you Lauren? Any less - you're happy.
Alright. So I make a pretty superficial skin incision just because this area is very vascular, and we'll use cautery for a lot of this. You can see how deep that incision is in the cleft, and that's the hardest part to heal after. This side is less medial and less inflammation and therefore less - less bleeding. We're at 20-20, Lisa.
Teresa, could we trouble you to suck some blood off the wound when possible? Our medical students are away around the holiday, so we're getting Teresa to pull - do a little bit of extra work here. I go real slow here just for hemostasis - mostly so that I can see what we're doing. The other part is I - I know that the risk of hematoma is really high, and so we're incredibly meticulous with hemostasis at every level of this case. The problem with the hematoma is that it would lead to infection, and infection in this area for - for someone like him could mean an open wound for anywhere from 6 to 9 months. So we try to obviously minimize any risk to the patients.
So right now I'm on the lowest part of the disease and going through, and the tissues don't look perfect - but I'm just going to cut through the skin, and - and then we'll see if we need to go lower. This is scar that I'm cutting through, so clearly, someone has been here before. I don't mind leaving some scar behind. We just don't want to leave any disease behind. So I was very gentle with my touch on the skin on the lower part here because that part was staying behind. It's midline, it's been manipulated before, it's really fragile, and any postoperative wound complications typically start there for two reasons. One, there's a lot of tension in that area because we're moving - we're moving the skin and fat literally an inch up, which is why the - the cleft lift procedure was coined that way. So there's tension. It's also closer to the anus. It's also you're moving it a lot laterally from midline, and so that's the most problematic area for wound healing. I would say somewhere 1 in 4 to 1 in 5 kids that have this surgery will have some sort of wound issue that we typically deal with in the office. Once or twice a year, it gets significant enough that we may either debride in the office or even get the help of one of our wound colleagues to help with wound closure. So the chronic inflammation here causes the - the bleeding.
So in terms of the - what we do for the patients, we see them all 2 weeks before surgery. We obviously meet them well before that, but we do a - to get them ready for surgery, we do a 2-week pre-op visit - make sure that there's no active abscess that needs to be drained. There - there typically is not one, but occasionally, there is. And before I instituted that change, I had patients drive from pretty long distances and show up with an abscess on the day of surgery, and we end up doing just an incision and drainage that day and - and delay the definitive procedure - and that's obviously disappointing for everybody. So now we make them all come in at two weeks before surgery.
Now we have the - our PA will evaluate them. Can I use your name, Lauren? Here we go. So our PA Lauren typically evaluates them 2 weeks before, and then, if there's any issues, I'll - I'll see them but typically not. At 2 weeks, we start them on an antibiotic - for 2 weeks before surgery, and then they come today. Do you want to start down or up? I'll start up.
Alright, I'm going to switch to the spatula - the wider Bovie, the one that's protected. So I'll get some hemostasis before we get going. I'm removing this all. As you can see, we remove a fairly narrow swath of skin. It was only about 4 - 4 and 1/2 centimeters to start with, but once the - once it's removed with the tension on the incision, the wound is quite large. So that - the key to this part of the dissection is to only remove disease and not remove normal tissues. I feel like I didn't open this enough here. I need to go a tiny bit deeper into the sub-Q fat. I didn't quite get through the dermis or scar. Feels like I'm outside the scar here, so we cut a little bit more lateral than we normally would on a person that has not had disease - a little bit more lateral on the unaffected side. We always have the incision skewed to - toward the affected side. That's where we're going to move tissues over. We'll go. Let's do this part.
So here, I'm looking for changes in color. So obviously, you can see nice yellow healthy fat, and then there's some whiter areas. Often, the disease will look a little bit more purple. Right now, I'm just hugging skin, and as long as I see healthy yellow fat, I'm going to stay superficial. The minute I start noticing a change in color, we'll have to head down a little bit deeper - and I'm noticing a little bit of white scar here, so it's time to - to get in a little bit deeper. It's a little subtle, but it's - it's certainly disease here. And so now I'm in that plane between what looks like disease. Here I've gotten into the cyst a little bit, so I'm going to go in a little deeper. So I wasn't quite deep enough. You retract here and here - just use two hands. You're good. Do that. Yeah.
So we're going to have to go quite a bit deeper and I did to get around it, and over here it's actually more on this side than expected. So I'm going to go straight down. So the sinus tract is actually a little bit off to the patient's left side of midline, so this is quite tricky. So this is good from an educational standpoint to notice that we make tiny little - do you have a skin hook? So we've got just - you know, we've got a little bit more complicated than I anticipated because of the recurrence, and so I'm just opening up widely to get us into nice healthy tissues. And over here, it's a little hard for me to tell whether we're looking at scar - maybe an Army-Navy even. Thank you. Teresa, can I trouble you to do this one? Perfect. So over here, we're underneath the disease.
So it's about pattern recognition, and what I expected was not what I found - and so I made an adjustment to go a little bit deeper. We're now just posterior to the sacrum, and we can see that there's a nice healthy tissue plane here - and the trick will be to connect this with where we're going. So what I'm going to do is I'm going to turn the tension to this side here. So what I don't want to do is take more than I need to. I think Adsons are fine here. I got this. Here he's got a little bit of recurrence, and we saw that the disease was midline. So I'm going to go across some scar and see if we find disease or if it's just scar. This is just normal fat, so I'm just going to get us a little bit of exposure and know that we're in a good spot, and it's just okay here. I just want to go back to here. Can I have that? Like that. So what I'm seeing is white scar tissue. This is not healthy fat, so I'm going to go very slowly through it and see if we - we run into purple disease, which we ran into over there, or if we just go through scar. And then I'll know where the end of our dissection is going to be. Just like any other operation, we don't want to be operating in a hole, and so I wanted to get exposure on either side of the trickiest area before I got there.
So now I'm underneath the cyst. We're not in a hole. We've got a good plane where I can see normal tissues - well, a little bit scar, and then we've got clear disease here. So I can grab - this is both scarred sinus tract. Let's go from the top - the bottom. So here - this is the side that we're going to be using to - to close, so I want to keep as much normal, healthy fat as possible, which will help us with the wound healing. I think you guys can see how vascular this is and how - how likely hematomas are. So I'm going to let Lauren dissect a bit on her side and just get underneath this tissue. Can you guys see from - from over here? This is really important.
So we've got this fistulous tract here, and we've got - do you have anything to point with? Like - no, something we don't want to use later. Yeah, that'll be good. So, the fistulous tract started from these pits, went all the way down, and then turned its way toward the opening, and over here, I got into it a little bit too superficially - so now I - I just want to make sure that I get it all out. There's a little bit of edema. You can see a little bit of - tiny bit of bubbling and fluid - just to show how this is been chronically inflamed. And this will get us underneath it completely, and there's almost always edema just underneath the cyst. So that makes me feel good that I - I've gotten what I was going for. But it's - it's deep, and it's wide. And here I'm cutting across scar from the previous surgery or maybe even a little bit of disease. A little tricky to tell disease from scar in him because of the previous surgery, so you need to make a little bit of adjustment to get it all out. Yeah, that's perfect. Let me just see where we're headed. We've got very little left here.
Okay, so we've taken out a little bit of skin but a lot of wide disease here. Very unhealthy, very minimal normal fat was removed, and this is clearly dirty and goes to pathology. What I'll do is grab some - get some hemostasis, and then we'll - we'll change gloves, irrigate.
So whether we have to do this or not, not real clear, but I'll change my outer gloves. Now that we've removed the infection, irrigate, get some hemostasis, and then the hard part of the case comes where we're going to have to mobilize all this left glute to the right. So in terms of dividing the procedure, really the - the first step is marking - marking what needs to be excised so that the incision is skewed and off the midline. On the top, I was using the fact that his glute was a little bit flat already because of the previous procedure to not go quite as wide so that I wouldn't have to remove quite as much disease, but if we - if we measure the defect, the result of that amount of tissue we move is an excision of probably something that looks like about 7 centimeters by 11. We'll measure it. I guess we'll change gloves and then measure stuff.
So in terms of the length of it, the ellipse is about 12 centimeters wide, and at its maximum, it's about 9 centimeter wide. So it's a - it's a pretty huge surface area that we have to close. So most of the time - I guess I'm going to switch sides with you and work on this side. This part is the - the creation of a flap, and so I'm going to go down to the gluteal fascia - and in fact, we take a fair amount of fascia once we get down to the glute in order to - to close this. So I'm just going to start the process now - been quite a lot of dissection on the gluteus maximus muscle, so. I'm starting to see muscle come into view now, and this is going to be the part that, as I mentioned before, we're going to want the most amount of mobilization to decrease the tension.
Now there's a lot of perforator blood vessels that come in here, and one of the trickiest parts is being meticulous with the hemostasis - and so you're going to see me - once I - it looks like we're done with the dissection, I'm going to spend a lot of extra time going over, trying to make it bleed. So I'm - I'm just peeling the fascia off the glute here to get this fasciocutaneous flap to have as much mobilization as possible, and then if there's still tension after we bring the - this flap over, then we'll - we'll do this for the skin and subcutaneous fat as well. I don't think we'll need to with him. we can see the muscle and fascial well here and - you're good. I got good - really good exposure right now - so not going to give it up. That 9 centimeter area has just a lot of tension. So I look through, and I've got at least 5 centimeters mobilized over here. Up top, I probably need to do some more, and then certainly on top and up to here, we'll mobilize on my side as well.
So this creates a pretty big potential space here, and this is where that drain is really important. With a space this big, we're going to want to leave the drain in there at least until Wednesday. And so we kind of knew that ahead of time, and so he has a postoperative appointment on Wednesday to have the drain out. If it needs to stay in there longer, we'll have them call ahead and see how much is coming out of the drain. So the whole point of this procedure is to change the anatomy from being a cyst or a sinus tract deep in a crack - and - and the problem with the crack is that it's close to the anus - it's where sweat pools down - lint, hairs get in there - and it's a really hard area to keep clean, and so the recurrence rate of the disease is really high. And what we're doing with this surgery is we're changing the anatomy so that the tissues are actually flat instead of deep in a cleft, and so that increases the odds of healing dramatically. And so the - the reported recurrence rate is somewhere around 5%. I can think of two and potentially a third person that I've done in my 11 years of doing this that have come back, and that's out of - out of about 150 patients. Now there's something that we lose for follow up, but it's a pretty low risk of recurrence. Whereas for traditional surgery, recurrence is anywhere from 10% to 50% depending on the literature that's quoted. Alright skin hooks, to me.
So here, we're already way over to the midline, so when - when Lauren starts working here, she'll be pretty close to the muscle pretty quickly. And this is just to release and give us a little bit less tension to work with. If we just released one side, there would be no flexibility on the other side, and it would make it really hard to close this. Yeah. We can see the fasciculation of the muscle, so that's - Lauren knows where she's close to the muscle here. So that's the feedback we use to - to not go deeper and not get into the muscle. So this part of the dissection is very similar to a mastectomy where you're taking tissue off the - the pectoralis. We need to definitely mobilize more here where there's - so down here, there's not a lot of tension and - and healthy tissues because this is virgin area that hasn't operated on. Here, there's a lot of scar.
So I'm going to mobilize a little bit more here mostly because the principle that I talked about - about getting the - the cleft obliterated has already been done here by the previous surgeons up high. And so, I need to restructure the anatomy a little bit less up high, but I'm worried about the tension up high in terms of healing. The second piece - that lift part of it. There's a component where you're bringing the incision so it's a little bit off the midline, so if there is a wound complication, it's not in a potential midline cleft. And so, the - what we're doing here is just mobilizing a little bit more. It's going to make it a little easier to close, but it's going to make the incision a little bit more midline up high where it's less important. Down low, we'll still keep the - the incision so that we're really moving it off midline. I think we're okay here. I think we should do the top, so. This is where we have - so we mark here. You want - I'll have skin hooks back.
So we'll mark about 1 centimeter of subcutaneous fat. It'll give us a landmark of where to suture to, and if there's a lot of tension - a little bit more, Stef. Yeah - yeah, I guess that's good. Give it a little - yeah, that's good. So this step here kind of marks a stage closing. So the - the first stage will be to take the - the gluteal fat pad from the patient's left side and bring it over and connect it here to the right - and the top part of where we're going to do that is what Lauren is marking here, and I'll mark my side in a few minutes. Once we've rotated and brought over the - the gluteal fat over to this side, I'll decide if there's enough flexibility in the wound that it'll close the way we've marked it, and if there isn't, then we'll - we'll develop skin and subcutaneous fat tissue flaps so that we can really close it with minimal tension. This part here is going to be a little trickier. Toothed forceps for me. Got it. Thanks, Teresa.
So I'm just going to continue along the line of what Lauren marked until we get to the - the lowest part of the incision, which we - we've got some scar here - not a lot. So this scar here tells me that the last procedure was done all at a rel - relatively superficial level - sort of the - the most superficial level that we typically work in. And I've done enough of these revisions, and initially, I used to have plastic - a plastic surgeon I work with closely help me with these, and the point was to make sure we're adhering to good plastic surgery principles. And based on his advice, we - we've modified the procedure a little bit to make sure that we're really going down to the - to the glutes to mobilize our tissue and reducing the tension, and that's made a big difference in terms of the - the recurrence rate and the - and the in - the wound complication rate. It's - it's quite extensive procedure, but the outcomes are really good. It looks like the procedure should be painful because we're doing a lot of - a lot of work. Yeah, I think that's as far as we want to go here.
So we've created sort of a shelf, so it's a target area. The goal is to bring the tissue that's over here, connect it with over here, so that seems like a - a pretty good stretch. Now our tissues are on stretch because of the - the tape, so once we release the tape, we'll be able to tell whether we have to do more dissection, so. Right now, we're going to spend a lot of time on hemostasis, so we'll take some Army-Navy's.
So I go - so in terms of marking, I go about 5 centimeters on this side, a couple centimeters on - on the side that we want to leave alone. As a general principle, on patients who have less disease or shorter length, sometimes I don't have to mobilize quite as much. On - on this kid we probably went as far as 6 centimeters to - to release, and through experience, you get to know if you've gone far enough - but we'll test it anyway, but as a general rule, 5 centimeters is the right amount. So I'm pretty vigorously rubbing on any cut surfaces in hope of causing bleeding now as opposed to next week or during the holiday when the patient's at home, but you can see the muscle striations. So Lauren went right down to the muscle, stayed in a nice, really clean plane, and - so we're in good shape here. Down here, I think we'll be good - need a little hemostasis. No. So I'm pretty happy with this, but I'm going to verify. So we're going to put some irrigation in - bacitracin. So we'll take a look and - and if - this looks pretty dry. There's nothing coming through here, so I'm really happy with that. I'm going to try to make it bleed again and test it out again, and even after everything, it's still oozy.
I think the extra 10, 15 minutes spent here is a really, really good investment at reducing the risk of hematomas postoperatively and ensuring a better outcome for the patient, so it's - I can't stress enough how important hemostasis is. We've had - a few summers ago - probably 5, 6 summers ago, I had a couple of kids who developed hematomas, and it was sort of a - a - not a significant one that required going back to the operating room but really delayed the wound healing a lot, and one - one of those kids is the - the one - one of the ones that I talked about having a recurrence. I think we're - we'll see. Let's release the tape. Let's switch sides and see how we - we look.
We've got some good mobile - mobility, and the question is did we do enough here so that they'll - can come together. There's clearly a lot of tension, so I'm going to close this in five layers so that each layer takes away some of the tension - and as we - we bring things together, I - I know that this will come together nicely here. The bottom part is to - always the trickiest part because we really have to alter the anatomy here. So Teresa always reminds me I got to put a drain in at this step, but since she standing right here, that was the visual prompt I needed. May I take the specimen out? Please do.
Pilonidal cyst - cyst in sinus, recurrent. Boy, there's a little bit of scar or something. There we go. So we'll put a - a Blake drain in here. A little one, huh? Do you want a big one? No. Is this a 10? I think - yeah, it's a 10. This is good. I think so. This side - no, I - I think - so I'm learning that a smaller drain is effective at draining and will stop draining sooner than a bigger drain, and sometimes leaving this drain in there longer is not always in the patient's best interest. So, this is a 10 Blake drain. It'll fill the surface in here nicely. We'll get a little bit of bloody drainage out of it initially, but this drain will typically come out on Wednesday - Tuesday or Wednesday in his case. We'll keep it in there just because it's a wide surface area. He's had previous surgery. So the first post visit - postop visit is at 5 days. If the drain doesn't come out, we typically have them come the following week and get the drain out. We always see patients 2 weeks after surgery.
I'm going to put in a - a suture. Actually, Lauren will put it in. It's a Monocryl suture that comes out and that - that suture is - it's just to have less foreign material on the skin, and - as well as it - it makes us see the patients back. Do another net. It makes us see them back at two weeks. We then see them again at 4 weeks after surgery, and if they've done well at that point, I let them resume their activities. In the first month, the restrictions are absolutely no sports, squatting, lifting for a month, and the first week, I tell them not to sit down directly on this unless they're going to the bathroom so that we minimize the - the tension and pressure on the - on the wound - and - and people do fine with that. People who work typically take the entire week after the surgery off and then go back to work that following week. People who are in school do the same but with school, so he'll be able to go back to school in about a week and a half, two weeks. Alright so, I think we just do our usual here, yeah? Let's take PDS and 2-0.
What's that? Do you want to get the bed down a little, or? Sure. No - no, bed - bed can go down a tiny bit Can we get the bed down a little, please? So my goal is to get this level to attach here. I'll pull this up a little bit just because we - good, good - because we have a little extra tissue on the bottom, and I do this in two layers so the - the first layer helps me match this up. So I'm going to grab a little bit of the - the gluteal fascia that we peeled off this side, and we'll take a nice big deep bite here to - to bring it together and - do you want to make like this a little bigger or not really? I don't know. Let's see if we need to after this layer. I'm not sure. What are you - what are you thinking? Well it just seems like this has kind of a long way to go - yep - because we've loosened this up a little bit. We'll have - that's a good. No, that makes sense. Let's do that. Let's tie this knot, and then we'll - we'll do that.
So typically, we get three s - three stitches out of each suture. I'll go and load the needle up and get ready to suture. Our - our tech or our student cut. Lauren ties the knot, and so it's really efficient that way. I think I'm going to take Lauren's advice to say that this is a long way to go, so having a little bit of a subcutaneous flap here is going to help with the closure later. I won't go too much, but I think a little bit makes sense and - as well as marking over here. So let's have the skin hooks back. So there's a lot of scar here, and my concern is vascular - the vascular supply, so I'm going to stop and just only do this if we have to do more. Why don't you mark your side a tiny bit more because we can get more here. There's a lot of - of sub-Q fat, and so I think the way we'll get it is from this side. So because we're - we're dealing with a re-do bed, I'm a little bit worried about the blood supply, and so I'm going to use this side more that hasn't been operated on. Again, that'll bring the incision a little closer to the midline - not our intent. Go a little deeper - yeah. This feels a little scarred to me too. Yeah. That's nice. That's good. Let's not get too greedy here, but this'll be really nice. Alright. Good.
Alright, Teresa, if you don't - be so kind as to cut some sutures for us. So I'm going to keep these sutures pretty close together - lots of them. Each one is going to have a little bit of the tension here. So I think working with an assistant that you've worked with before that you can trust and has done a lot of these procedures with you makes a big difference in this because it allows me to load up the needle, get ready for the next stitch, help out, and just for the patient's sake, it probably saves anywhere from 30 to 40 minutes of - of time - just on this part alone - and that's just less time to have an open wound. And so here, I'm just taking the tension off as she sutures. So it's going to slow us down a little bit, but I think it's really important for the patient here. You can see we've almost bridged - we're at that 9 centimeter gap right now, and we have some - we'll be - we got extra skin here so we'll - we'll deal with that - but to me, this is the - the most important part of the - the deeper layer, and then there's the most important part of the superficial layer. It's all important. Nice.
So you can start seeing that this is going to line up really nicely. You can start seeing that the - the cleft is obliterated, and we've got a long way to go before we get there. I feel like I need to bring stuff. This is going to come up. This is all going to get rotated at the skin level, so w - you're right. We may end up taking more skin to mobilize it. I'll - I'll take a little bit of a bigger bite here - kind of like - to start shifting it. So this is all absorbable PDS suture - 2-0 PDS - and the reason I use this is it's monofilament - so reduces risk of infection. It will last in here probably 9 to 12 months. I use it in the deeper layers or in areas of tension. Vicryl just doesn't last long enough. It's braided, so it's more likely to - to have infections. And so I'll use that limited superficially where I just need something a little bit softer. Patients can feel these harder sutures, the - the monofilament ones, and so I won't use the - the PDS superficially - but this is kind of our workhorse suture. This was something I learned from our plastic surgeon Dan Driscoll. So the top part is going to be nice and easy to close at this point. The - the bottom - we're going to have to - to move some tissues around in order to make this work. Great. I'm going to go. I - I have a tiny little opening here we'll close up.
And then really the - this is sort of the - there's still where we marked. There's still the gluteal fat. So we're going to close this in yet another layer of the PDS, and I'm going to take a nice big bites here - not too big. Obviously, I don't want to make things too ischemic, sure. And - and this'll be the - the second of the deep layers stitch. Yep. Yep, we'll keep the - keep the PDS's going. So now with the tension off and the tissues together, I can put these retractors in. We can move things along a little bit smoother. I'm basically reinforcing the last layer, so I'm taking bigger bites.
I think this - this is sort of the - the biggest difference between traditional pilonidal surgery and what we do here is this deeper layer that we've been working on for probably well over an hour, hour and a half, between mobilization and closure and the fact that this allows us to get the incision off the midline. So this takes the tension off things, it brings it off the midline, it elevates the cleft, and this is what makes this procedure unique - and also very time-consuming. So as I get more superficially, I'm feeling a little bit of scar. The tissue's a little harder, and I have a pretty thin needle. I'm wondering if you can get me a CT-2 needle because I'm noticing the needle buckle a little bit. That's a nice needle. Thank you. So it's the exact same size needle. It's just a little thicker. It's a little bit easier to manipulate. So a slight modification because of the scar in a recurrent disease - normally, the SH needle is - is fine. So I'll move this retractor a little bit closer here, as it was falling out. That's nice - can see how much more needs to be reinforced here.
Try to bury these sutures. They are pretty deep overall, but I'll try to get them so that their - the knot is inside the fat. As you can see, you can barely see the edges of the knots. I just like to have as much fatty coverage over these sutures so they don't bother him, they don't poke out, they can't cause holes in the skin, and that's why I use the vicryl softer sutures on the superficial areas, especially down low - because just a mechanical irritation can cause these to poke through and cause little holes along the incision. So these are the last few stitches of - of the deep layer. Now the - the superficial layer is where I'm going to take deep dermal stitches and really line - line up or approximate the dermal edges, and so that gets a little tricky down there where we have extra skin and we're moving things over quite a bit. Okay, so - can see how the - the dermal edges here want - want to be next to each other. Here we have a little bit of extra that I'm going to bring over. So, I'll need Adsons. I think w - once it's together, it'll be a little - very little tension, so. So you can see here, this is going to come up here. This will come up here, and so we'll just kind of march our way up.
I'll put these about a centimeter apart, starting from the bottom, and then I'll stretch out the skin - see where it - where it needs to - to end up. I'll go directly across. So here, I'm at about 4 millimeters from the edge of the dermis and - or the epidermis, and I'm still in the dermis here at about 3 to 4 millimeters. And I won't get this right every time, and I'll - I'll make sure that it's perfect before we - we stop - but the closer things are - so if I look at this, the edges do come together real nicely, so I'm happy with that. Now there's almost no tension on this area here because we did all the work down below, and so I'm - I'm pretty happy about how much we need to do. So I'll do a layer of the 2-0, and then we'll do some 3-0 vicryl in between that. So again, I'll march about a centimeter - sub-Q fat to deep dermal. I feel that I'm in deep dermis - feels about - again, anywhere from 3 to 5 millimeters from the edge, line it up, feel that I'm in deep dermis again, and come out deep. And I'll tie these knots just so that I can see that where - where things are approximated, and I'm happy with that.
The - the corner, which is going to be our next part, is the part that we're always the - the least happy with because there's tension and this used to be the cleft itself. And so I'm bringing tissues that were naturally v-shaped and making them flat, and so this part here is always the - the most concerning part of the case in terms of bringing the tissues together. They're not totally healthy because of the tension that there was here. So again, about a centimeter - and I know that this is the part that we're always the most concerned with. That looks okay. We're getting there. These we cut as short as possible to minimize the foreign body here. Yeah. There's a little bit of oozing here. We just - I want to just check some hemostasis as we go here. It's okay. And we want to go like that, so we're getting there. It's interesting. We did a little bit of extra mobilization here, and this is actually higher though started lower than this side.
So could have probably done a tiny bit less mobilization even than we did, and I think that's a really - hopefully, a good lesson for everybody out there. We're - we’re human. We're not perfect. So we - we do the best we can, and we make adjustments for the tiny, little errors that we're inevitably going to make. That - if you could hold that down just for a second, I want to make sure. Good.
So I - I think no tension here is really the most important piece to the healing and an approximation which is as close to perfect as you can get it. We're on the same level plane, and so we want to just kind of get this approximated so we have - I think we're still moving. We got a little bit more up here. Yep. So we do this splenoid layer. I'll do a couple more from here. So while I think this looks pretty good and brings it together nicely, we'll still do two additional layers of closure after this. There's a 3-0 vicryl layer that's - just will kind of span some of the gaps here, and then there'll be the Monocryl layer that we'll do. So you can see how easily just bleeding happens - just putting a stitch in. So we'll tie the knot, and this is a really good demonstration. If I put the needle in, got bleeding, and I kept going through, we're going to tie the knot. If that - that should take care of the bleeding. Doing that deep - one of the - I don't know how many stitches we put in I repositioned, and that's a risk of - of a hematoma in this.
So patient-selection-wise, we see - what do I see? Probably about 300 new patients a year. 300? 3 to - no, maybe not. 200? 200. We operate on 20 to 40, so we operate on 10% to 20% of patients that we see. Most patients end up being treated medically. We treat everybody with the - we tell them to shave oftentimes, use the Hibiclens, and quality-of-life-wise, they do well enough that they don't need surgery, which is awesome. I feel like our job is as pilonidal experts is to give them the best quality of life whether it's through medical treatment or surgical treatment, so. There was no avoiding surgery in him. So we'll need some 3-0's to make this. So there's a little bit of tension on the skin here, so we'll use a - we'll do the - another layer. I wanted these to just kind of approximate the - so that we have a nice straight line and... So we'll need some 3-0 vicryl. Yep, and then the Monocryl to follow. I'll take the - the local though next and a snap.
So tiny little opening - but I'm going to shove 10 cc's of local into the - into the pocket we've created. I'll suction back, and it's very, very minimal staining. And this is almost like a temporary PainBuster - pain pump - just to give a little bit local anesthetic deep in there while we're closing before we connect the bulb syringe. I don't need to do a lot here - just there.
So I'm going to put a couple more of the - the 3-0's in areas where there's a little bit of separation. I know that the - the 3-0 Monocryl will - will do a nice job bringing things together. So this I'll take a little bit of an angle just so that I don't need quite as much suture material in here. There's a balance between having not enough suture to - to perfectly approximate it and having so much suture superficially that it could spit out, and so I'm trying to take sort of wider bites here - not a ton of tension.
You can see, it's coming together really nicely in this part here. He's got a little more fat over here from before that we didn't take out, and that's how he's going to be. Over time as the fat will distribute, it may balance out a little bit. I'm not going to worry as much about the cosmetic evenness of his buttock, considering where we started in terms of recurrent disease.
And - so for dressings, once Lauren does the Monocryl, there'll be some Steri-Strips that we use to take off a little bit of the tension on the skin. And then we do a pretty bulky dressing with lots of gauze and fluffs and a foam tape just to give a little bit of extra cushion, and that dressing stays on until the drain is removed on Wednesday.
So they do sponge baths. He won't shower until the drain is out in terms of the post-op instructions. What's that? And he won't sit for a week. And he won't sit for a week.
Dr. Masiakos was a pediatric surgeon - taught me how to do this procedure. He learned it by talking to Dr. Bascom in Oregon. So he should take credit for - gets credit for bringing this procedure to New England. He taught me how to do this in 2006. So typically, the - the younger kids he takes care of - or - or patients that - I'm at MGH, and oftentimes, I'll take care of the - the older population - but we cross over. Really complicated cases, we've done together as well. We trained together at BU, so we - we've become close colleagues.
So in terms of post-operative instructions, we give patients printed instructions. They're also online on our website (pilonidalclinic.com) so that anybody has access to them. Really important that the patients aren't sitting down directly on the wound. There's a lot of tension there when we close, and so we - we find that that part is - is very important. We bring the patients back at about 5 days to remove the drain. Once the drain is removed, we put a waterproof dressing on, and they're beginning to shower. We instruct all our patients to shower using three drops of Hibiclens soap. They put it on their hands, lather it up, and then wash their whole back side with that. That's a really important method to keep the area as clean as possible.
They then come into the postoperative appointment at 2 weeks. We remove the Monocryl stitches at the ends, and then we'll shave the area after we remove the Steri-Strips. It is critical to keep hair out of any pilonidal wound in the immediate postoperative period and even up to 3 months, so we encourage shaving at every visit but also at home - typically, with clippers - not with a razor blade that could puncture the skin. We then see the patient one month postoperatively. At that point, if the incision is - is perfectly healed, they are doing well, there's no drainage, we give them the go ahead to resume full physical activity including sports.
We find that about 75% to 80% of our patients have a very prescribed, typical course, and about 20% to 25% of patients will have some opening of their wound immediately after surgery - and that's why it's so important to see them so many times after surgery so that we can manage the wound appropriately. Follow-up can also happens at 3 months, 6 months, in a year, and if they've done well at one year, we discharge them.