Effect of Dead Space Reduction in Pilonidal Sinus Surgery: Introduction of a Novel Technique

Pilonidal sinus (PNS) disease, which affects the natal cleft in the sacrococcygeal region, can be chronic and undergo acute exacerbation.¹ The prevalence rate of PNS disease is 26 per 100 000 people in the United States.^2,3 Both environmental and genetic components play a role in the etiology of the disease. The treatment of patients with PNS disease focuses primarily on the surgical removal of the affected tissue with the removal of all hair nests, fistular tracts, and sinuses.^4,5

Although many different surgical techniques have been described for the management of PNS disease, this condition remains associated with a high risk of recurrence,⁶ and research for the ideal management approach continues. The principal means of treatment involves surgical excision. The closure technique for the defect after excision is at the discretion of the surgeon and involves a number of different approaches, including primary closure, lay open for secondary wound healing, marsupialization, V-Y advancement flap, Z-plasty, Limberg flap, or Karydakis flap.^7-9 Among those approaches, the Karydakis flap is one of the most frequently utilized asymmetric flap closure techniques with a reported recurrence rate of less than 1%.⁹ In utilizing this technique, all sinuses are completely excised with a vertical, asymmetric, and ellipse incision. After the excision, a subcutaneous flap is created by undermining the medial edge and advancing across the midline, allowing the suture line to be lateralized.¹⁰

Alternately, this technique is associated with the formation of seromas in the dead space due to the presence of a subcutaneous flap, which may lead to infection, wound dehiscence, recurrence, and a long-term need for surgical drains or a prolonged hospital stay.^11-13

In this study, the objective was to report early results about the potential reduction of dead space volume in the risk of complications associated with this new surgical method developed by the authors.

The study protocol was approved by the Ethics Committee of Faculty of Medicine, Harran University Ethics Committee , Şanlıurfa, Turkey, (No:74059997.050.01.04/80), and all procedures were performed in accordance with the 1964 Declaration of Helsinki and its subsequent amendments. All participants provided written informed consent after receiving information about the study procedure.

Inclusion and exclusion criteria

All patients who underwent surgery for PNS disease between April 2015 and June 2016 were eligible for study inclusion. Patients with a higher ASA score, obesity, insulin-dependent diabetes, and allergies to anesthetic drugs who had a previous PNS surgery were excluded. Patients also were excluded if they declined to have this new surgical procedure and were younger than 18 years. Patients who discontinued follow-up appointments during the postoperative period also were excluded.

Surgical technique

All patients were placed in a jackknife position and administered spinal anesthesia. During anesthesia induction, 1 g of cefazolin sodium was given intravenously. Gluteal skin was retracted to the side using adhesive bandages to expose the intergluteal sulcus, after which methylene blue was administered into the sinus opening at the gluteal area (Figure 1). Following an incision of the skin and subcutaneous tissue, a total sinus excision (including all sinus tracts up to the point of presacral fascia) was performed. The volume of each removed piece was measured using a beaker and physiological saline. The volume of the overflowing physiological saline was taken as the total piece volume. A Karydakis flap extending along the incision was prepared with the medial edge of the wound being 1 cm deep and extending 2 cm to 3 cm medially (interiorly) (Figure 2); it was stitched to presacral fascia using 2-0 polyglactin sutures (Vicryl; Ethicon Inc). To reduce lateral dead space volume, a skin excision of 5 mm to 10 mm was done along the flapside (Figure 3). Re-excision of the skin allows for more lateralization of the suture line and reduces the dead space volume. The amount of resection should be adjusted to avoid tension. Subcutaneous tissue was approached with 2-0 polyglactin sutures. Skin closure was accomplished with 2-0 polypropylene sutures (Prolene; Ethicon Inc) using the vertical mattress technique (Figure 4). No surgical drain tubes were placed. After patients were discharged on postoperative day 1, they were instructed to change the dressing daily. On postoperative day 10, sutures were removed in the surgical outpatient unit (Figure 5). Follow-up visits were performed at 1 month and 6 months postoperatively. Complications such as wound discharge, formation of seromas and/or hematomas, and skin dehiscence were recorded.

Statistics

Results were analyzed using SPSS version 20.0 (IBM Corporation) statistical software. The significant difference between groups was measured with 1-way analysis of variance test. A P value of less than .05 was considered statistically significant.

In total, there were 19 females (23.75%) and 61 males (76.25%), with a mean age of 24 years (range, 18–49 years). The mean sinus volume was 26 cc (range, 8–80 cc) (Table 1). The patients were divided into 4 groups based on the volume of the excised tissue: 0–20 cc (n = 43), 21–40 cc (n = 23), 41–60 cc (n = 11), and 61–80 cc (n = 3). The mean duration of surgery was 40 minutes for the initial 40 patients and 35 minutes for the remaining 40 patients.

Complications occurred in 10 patients (12.5%) whose mean sinus volume was 23.5 cc (range, 10–40 cc). Of these, 4 had delayed wound healing, which on average healed after 20 days of follow-up. Seroma formation occurred in 3 patients; in all 3 instances, the seroma resorbed and healed spontaneously without intervention. One patient returned to the emergency room at postoperative day 4 due to hematoma formation. Drainage was performed under local anesthesia, and the patient was admitted. The wound was incised after 3 days, and the patient was discharged without additional complaints. One patient had minor wound site infection with seropurulent drainage, which was managed with daily dressings; the infection healed within 2 weeks. Another patient was found to have abscess formation at postoperative day 6. The patient was admitted, the abscess was drained, and daily dressings were applied. The wound was left to secondary healing, and the patient was discharged on day 5 after admission.

No statistically significant associations were found between the volume of the excised tissue and risk of complications (Table 2). All patients with complications experienced healing after follow-up treatment within a maximum duration of 5 weeks. In patients without complications, the mean duration of healing was 2 weeks with a return to work time of 3 weeks. Recurrence was not identified during the follow-up period.

The current study demonstrates that the presented surgical technique had a better outcome than the original technique of Karydakis in the treatment of sacrococcygeal PNS disease. In the original Karydakis technique, the shift of a suture line from the midline is utilized, which is an undesired element of the primary repair, describing asymmetric primary closure.¹⁴ The primary aim of this method is to remove the intergluteal sulcus, which is thought to propagate ingrown hair formation and avoid formation of scar tissue in the deeper layers of the intergluteal sulcus.¹⁵ A disadvantage associated with this procedure is the failure to adequately obliterate the dead space formation after excision, particularly among patients with thin subcutaneous tissue in the gluteal region. An attempt is usually made with drainage measures to prevent complications such as seromas and/or hematomas associated with the presence of this dead space. This potential dead space appears to be associated with several complications, such as seroma and/or hematoma formation and surgical site infections.¹⁶ The technique described herein flattens the intergluteal sulcus, which predisposes the formation of ingrown hair without any scar formation. Due to re-excision, the suture line is further displaced (~5 mm) toward the lateral of the midline as compared with the standard Karydakis procedure, detracting the lower sutures from the presacral sulcus and anal area.

In addition, the absence of surgical drains negates the risk of drain-related adverse effects, providing comfort for the patient and allowing early discharge at postoperative day 1.¹⁷ In a study by Karydakis¹⁸ involving 7471 patients, the reported complication rate was 8.5%, whereas the mean length of hospital stay was 3 days, healing duration was 10 days, and complete healing process was 3 to 4 weeks. Other studies found the mean return to work time to be 17 days.^19-24 In 2013, using the standard Karydakis procedure, Yıldız et al²⁰ reported a postoperative morbidity rate of 9.33%, a mean hospital stay of 3.34 ± 1.42 days, and a mean return to work time of 15 days. The mean time to return to work in the study is comparable to the mean time to return to work reported by Karydakis.¹⁸ This period was slightly longer in patients who had complications in the current study. In this study, 10 patients (12.5%) had complications; of these, 2 patients (2.5%) experienced major complications requiring reintervention and the remaining 8 (10%) did not require additional treatment other than daily dressing changes. Although the complication rate observed in this study was higher than that reported by Karydakis,¹⁸ the difference in complication rates may be explained by a learning curve with the new surgical technique as well as a small patient population.

There is no consensus in the literature regarding drainage. Milone et al²⁵ studied the use of drains in PNS surgery and found that using a drain did not decrease the rate of infection or recurrence. Gurer et al²⁶ observed fluid collections in 8% of patients with suction drains, which contrasted with the 32% prevalence of patients without drains.²⁶ Previously, drains have been reported to be removed after a mean duration of 1 to 3 days, although some have reported removal of the drains at postoperative days 6 to 7,^21-24 a considerably longer time than those reported in this study. In the current study, no drains were used, and seroma rate was 5%.

In a reported series, hospital length of stay (LOS) varies from one day surgery to several days. Sewefy et al²⁷ reported a mean hospital LOS of 4.9 ± 2.4 days for Karydakis flap. Ateş et al²⁸ reported hospital LOS 3.4  ± 0.94 days for Karydakis flap and 3.8 ± 1.19 days for Limberg flap. Because no surgical drains were used in the current study, no patients were hospitalized for more than 1 day with subsequent discharge on postoperative day 1. One of the 2 patients who required readmission had a hematoma, whereas the other had an abscess formation. Although the mean hospital LOS in these 2 cases was slightly longer than 1 day, it was still lower than that reported by Karydakis (1.14 days vs 3 days).^10,18 The additional skin excision performed on the side of the potential dead space results in a significant reduction in its volume and obviates the need for the use of surgical drains. The decision on the width of re-excision should be made during surgery to minimize the dead space volume while avoiding tension at the suture line (~5 mm for a volume of 0–40 cc, and 5 mm–10 mm for a volume >40 cc). With appropriate surgical technique and adequate hemostasis, it may be possible to significantly reduce the risk of hematoma and surgical infections without the use of surgical drains.

There are certain limitations in this study. This is a calibration study and includes a relatively small population. Another limitation is a lack of control group, which could be an obstacle to an objective assessment. Finally, the study had a shorter follow-up time (20 months) than other studies,^29-31 making it difficult to assess recurrence rates.

This new technique may result in less wound infection, seroma and hematoma formation, and wound dehiscence. Additional advantages of the technique include an early discharge and avoiding wound drainage by decreasing dead space volume with re-excision. This new technique could be a viable alternative to the standard Karydakis procedure, but these results need to be confirmed in further randomized controlled trials.

Authors: Abdulcabbar Kartal, MD¹; Metin Yalçın, MD²; Taner Kıvılcım, MD¹; and Ali Uzunköy, MD³

Affiliation: ¹Okan University, Istanbul, Turkey; ²Mehmet Akif İnan Training Research Hospital, Şanlıurfa, Turkey; ³Harran University, Şanlıurfa, Turkey

Disclosure: The authors disclose no financial or other conflicts of interest.

Correspondence: Abdulcabbar Kartal, MD, Okan University, General Surgery, Küme Street, Tuzla, İstanbul 34657 Turkey; narcabb@gmail.com