Comparative Outcomes of Surgical Techniques for Pilonidal Sinus: A Turkish Retrospective Study

Introduction

Pilonidal sinus is an acute or chronic infectious disease that occurs in the intergluteal cleft region, with an incidence rate of 26 in 100 000 [1]. It is more commonly seen in young men aged 15 to 30 years who have obesity, are hairy, and have a sedentary lifestyle [2]. This disease is characterized by subcutaneous epithelialized sinuses and inflamed pouches containing hair and foreign matter that form in the sacrococcygeal region [3,4]. Although sometimes asymptomatic, it usually presents with purulent discharge and abscess from the sinus tracts. Its cause and appropriate treatment were first described by Mayo in 1833 [5]. The diagnosis of this disease is made based on the specific history and physical examination by detecting characteristic midline pits in the gluteal cleft region [6]. According to the most widely accepted hypothesis, the presence of dermopathy, keratin plugs, hair remnants in the affected area, and related foreign body reactions are important [7]. Recently, it has been emphasized that the collagen type I/III ratio and total collagen amount in the midline sacrococcygeal region being lower than in the lateral skin region may be important in the formation of pilonidal sinus disease [8]. This disease negatively affects patients’ quality of life and social life. Although it has been a long time since its definition, the most optimal treatment method is still a matter of debate. Several surgical methods are used in its treatment. Patients who require surgery due to chronic pilonidal disease can undergo excision and primary midline closure (PMC), excision with secondary healing, or excision with marsupialization. Flap techniques such as primary excision with Limber flap (LF) or Karydakis flap (KF) reconstruction are recommended for more complex and recurrent diseases [6,9].

These known classical surgical methods require general anesthesia or spinal anesthesia. Especially considering that most pilonidal sinus disease is encountered in school-age children and young adults, these surgical techniques cause children to not be able to attend school for a long time after surgery and restrict social life in adults. At the same time, these classical methods also bring about large scars and cosmetic concerns. All these factors have led to the search for alternative treatment methods that are more minimally invasive and less disruptive to social life, for the treatment of pilonidal sinus disease. For this purpose, crystallized phenol and platelet-rich plasma applications have been used, especially in pediatric patients [10–12].

Recently, the development of surgical technology has led to the emergence of minimally invasive techniques in pilonidal sinus disease treatment, such as laser pilonidotomy (LP) [9,13].

Therefore, this retrospective study from a single center in Turkey aimed to compare outcomes following PMC, KF, LF, and LP in adult patients with pilonidal sinus disease.

Material and Methods

STUDY DESIGN:

This study was approved by the relevant clinical ethics committee (decision no: KA23/107). Informed consent forms were obtained from all patients. A retrospective analysis was conducted on the data of 476 patients aged 18 years and older who underwent surgery for pilonidal sinus disease at our clinic between January 2011 and September 2022. Fifty-four patients whose data could not be accessed were excluded from the study. The surgeries were performed by 4 different surgeons. The diagnosis of the patients was made based on the characteristic anamnesis and the observation of characteristic midline pits in the gluteal cleft on physical examination. Patients were divided into 4 groups according to the surgical technique: PMC (n=228), LF (n=82), KF (n=53), and LP (n=59). A flow chart of the study is shown in Figure 1. Demographic data of patients (age, sex, comorbidities, primary or recurrent disease, preoperative abscess history, and follow-up period), surgical findings (operation time, presence of drain, hospital stay, postoperative complications, and postoperative recurrence) and, quality of life (QOL) indicators (pain-free toilet sitting time, pain-free walking time, time to return to work, and patient satisfaction levels) were recorded. All patients included in the study were contacted by telephone to assess their satisfaction using a Likert scale.

SURGICAL TECHNIQUE:

PMC, KF, and LF were performed under spinal anesthesia with the classical technique previously mentioned in the literature [14]. Prior to anesthesia induction, all patients were administered intravenous cefazolin sodium (1 g).

PMC TECHINIQUE:

After spinal anesthesia, with the patient in the jack-knife position, the skin was cleaned with antiseptic solution, and methylene blue dye was administered through the pits. The sinus was removed together with the healthy tissue, using an elliptical incision to include the stained diseased tissues and pits. A drain was used in some patients, according to the surgeon’s preference. Subcutaneous tissues were approximated with 2/0 and 3/0 vicryl sutures. The skin was closed with absorbable or non-absorbable sutures (Figure 2).

LF TECHNIQUE:

The sinus tissue was excised down to the presacral fascia through a rhomboid incision, including the sinus pits and tissues stained with methylene blue. Then, a flap was prepared from the gluteal muscle and fixed to the presacral fascia. A drain was placed in the cavity in most patients. Then, the subcutaneous tissue was approximated with 2/0 and 3/0 vicryl sutures. The skin was closed with non-absorbable 2/0 monofilament sutures (Figure 3).

KF TECHNIQUE:

Sinus tissue was excised with an asymmetric and elliptical incision, including the sinus pits. Then, flap tissue was prepared, with a depth of 1 cm and a thickness of 2 cm. Then, the flap tissue was placed in the cavity to shift the midline by 2 cm. Depending on the surgeon’s preference, a drain was placed in the cavity in some of the patients, and the subcutaneous tissues were approximated with 2/0 or 3/0 vicryl sutures. The skin was closed with absorbable 3-0 sutures (Figure 4).

LP TECHNIQUE:

In the LP group, the procedures were performed as described by Dessily et al, using the NeoV 1470 diode laser machine device [15]. LP was performed under local anesthesia with the patient in the jack-knife position. After cleansing and brushing the skin with povidone iodine antiseptic solution after shaving, the sinus pits were excised and expanded with a scalpel. Then, the hairs were removed from the sinus with a mosquito clamp, and the sinus was cleaned with a curette. The direction, length, and width of the sinus were confirmed with the help of a stylet, to use the appropriate laser probe. Before starting the procedure, saline solution was injected around the pit and under the skin to prevent burning of the surrounding tissues.

A radial diode laser probe at a wavelength of 1470 nm was then used (Figure 5). Laser energy was 10 Watts. Fiber delivered energy homogeneously and continuously at 3600. As the probe was withdrawn at a rate of approximately 1 mm/s, the sinus shrunk and closed. If the channel did not close after the first pull, a second pull was made. The patient was discharged on the same day of surgery. The patient was recommended to use analgesics (preferably paracetamol) if needed. In the postoperative period, no special care was required other than covering the pits with compresses after taking a shower.

STATISTICAL ANALYSIS:

Statistical analysis was performed retrospectively. Descriptive statistics are reported using numbers and percentages for categorical variables and median (minimum–maximum) for numerical variables, depending on the data distribution. The normal distribution of the data was evaluated using the Shapiro-Wilk test. Relationships between numerical measurements were investigated using Pearson or Spearman correlation coefficients, depending on the data distribution. To compare numerical measurements based on sociodemographic characteristics and research groups, the Kruskal-Wallis test was used for independent groups with more than 2 groups, in accordance with the data distribution. For comparisons of proportions or investigations based on research groups, the chi-square or Fisher exact test was used. A significance level of P<0.05 was considered statistically significant. The power of statistical tests was determined as 0.80, and effect size was determined as 0.5 in G power analysis.

Results

PATIENT CHARACTERISTICS:

The median age of the patients was 23 years. Of the patients, 75.9% were male (n=335) and 20.6% were female (n=87). There were no significant differences between the groups in terms of demographic characteristics such as age and sex. Seventy-five (17.8%) of the patients were recurrent cases. There was no significant difference between the groups in terms of preoperative primary or recurrent cases (P=0.782). There was no significant difference between the groups in terms of the presence of preoperative abscess drainage history and comorbidity (P=0.480 and P=0.174, respectively). The follow-up period of the LP group was significantly shorter than that of all other groups (mean 14 months; P<0.001). Patient characteristics are summarized in Table 1.

SURGICAL OUTCOMES:

When the surgical findings were evaluated, the operation time was significantly shorter in the LP group than in all other groups (P<0.001; mean 35 min). While no drains were used in the LP group, drains were used in most patients who underwent LF (92.7%; P<0.001). In evaluating postoperative complications, the PMC group had a significantly higher incidence of seroma and wound dehiscence (P=0.006 and P<0.001, respectively). Although the incidence of wound infection was higher in the PMC group, this difference was not statistically significant. Necrosis did not develop in any group. Hospital stay in the LP group was significantly shorter than that of all other groups (mean, 8 h; P<0.001). Mean hospital stay was 24 h in the PMC and KF groups and 48 h in the LF group. The highest recurrence rate was observed in the PMC group during the follow-up period (14.5%; P=0.017). In contrast, recurrence occurred earlier in the LP group than in the other groups (P=0.016). The surgical findings are summarized in Table 2.

QOL OUTCOMES:

When the QOL of patients was evaluated, those who underwent LP started pain-free walking and pain-free toilet sitting statistically significantly earlier (P<0.001 and P<0.001, respectively). Additionally, patients in the LP group returned to work earlier (P<0.001). Patients in the LP group started pain-free toilet sitting on average 2 days after surgery, pain-free walking on average 3 days after surgery, and returned to work on average 7 days after surgery. A Likert scale was used to determine patient satisfaction levels. According to this scale, the percentage of patients dissatisfied with the surgery was statistically significantly higher in the PMC group (P<0.001). The findings related to QOL are summarized in Table 3.

Discussion

LIMITATIONS:

This study has some limitations. First, our study had a retrospective design. Second, the sample size of this study was small. Third, the follow-up period was shorter in the LP group.

Conclusions

PMC appears to be the most disadvantageous method due to its high postoperative complication and recurrence rates. The KF method, which has a lower recurrence rate, appears to be a safer technique. In selected patients, the LP method may be more advantageous in terms of QOL and patient satisfaction. However, further advanced studies with larger sample sizes and longer follow-up periods are needed.