Reliable numbers on pilonidal disease (also called pilonidal cyst or pilonidal sinus disease) can be surprisingly hard to find. This page gathers all the verified and trustworthy data in one place.

Every statistic here links to a named primary or authoritative source, so you can check it yourself or cite it directly. Where studies disagree, we show the range and say which figure is most defensible.

Any widely repeated number that could not have been traced to a real study, was left out and with an explanation at the bottom as to why.

You’re welcome to quote any statistic on this page with attribution.

Key statistics at a glance

• The commonly cited incidence is about 26 cases per 100,000 people, from a 1995 Norwegian study of 322 patients (Søndenaa et al., 1995).
• Pilonidal disease affects an estimated 70,000 people in the United States each year (StatPearls, 2023).
• Men are affected about 2.2 times as often as women in the original incidence study, and reviews commonly cite a ratio of 3 to 4 to 1 (Søndenaa et al., 1995; Medscape).
• Average age at presentation is 21 for men and 19 for women (Søndenaa et al., 1995).
• Family history is found in about 38% of patients (Søndenaa et al., 1995).
• Recurrence after simple incision and drainage reaches about 36.8% at five years, while off-midline flap procedures (Karydakis, Bascom cleft lift) have the lowest recurrence (Doll et al., 2019).
• Nearly 80,000 US soldiers were treated for pilonidal disease during World War II, which is why it was nicknamed “jeep disease” (StatPearls, 2023).
• Malignant transformation is very rare, occurring in about 0.1% of chronic cases (Malignant transformation case review, PMC9018021).

How common is pilonidal disease

The most widely cited incidence figure is about 26 cases per 100,000 people. It comes from a 1995 study by Søndenaa and colleagues in the International Journal of Colorectal Disease, which looked at 322 patients with chronic pilonidal sinus disease in Norway (Søndenaa et al., 1995).

It’s important to explain what this number actually describes.

The “26 per 100,000” is a calculated incidence figure from a single Norwegian hospital population in the early 1990s, not a modern US national rate.

It has been repeated so often that it now appears in most textbooks and review articles.

StatPearls states it directly: the incidence of pilonidal disease is estimated at 26 per 100,000 people and affects men 2.2 times more than women (StatPearls, 2023).

More recent population data suggest the disease has become more common. A nationwide Danish cohort study of 48,247 patients found the overall incidence rose from 26.1 per 100,000 person-years in 1996 to 2000, up to 39.6 per 100,000 person-years in 2016 to 2021 (Faurschou et al., 2024).

For the United States specifically, StatPearls estimates the condition affects approximately 70,000 people annually (StatPearls, 2023). Cleveland Clinic uses the same figure, describing more than 70,000 cases reported in the US every year (Cleveland Clinic).

For a sense of hospital burden, England recorded 11,534 admissions for pilonidal disease in 2000 to 2001, with a mean hospital stay of 4.3 days (Medscape).

Who gets it

Pilonidal disease is mainly a condition of young adults, and it skews strongly male.

On sex, the original Søndenaa study found it occurred 2.2 times more often in men than in women (Søndenaa et al., 1995).

Medscape puts the ratio higher, stating that pilonidal disease occurs predominantly in males at a ratio of 3 to 4 to 1, and predominantly in White patients (Medscape).

The most defensible statement is that men are affected roughly two to four times as often as women, with the exact ratio depending on the population studied.

On age, average age at presentation is 21 for men and 19 for women (Søndenaa et al., 1995). The Danish cohort found the peak age-specific incidence was among 20-year-old men and 18-year-old women (Faurschou et al., 2024).

The disease is uncommon before puberty and after age 40 to 45. Medscape notes it typically appears in the late teens to early twenties, decreases after age 25, and rarely occurs after age 45 (Medscape).

The usual explanation is hormonal, because puberty drives changes in hair growth, gland activity, and fat deposition around the buttocks, and these effects fade with age (AccessEmergency Medicine).

Risk factors

Several risk factors show up repeatedly, though the quantitative evidence behind them is uneven.

The strongest patient-level data come from the Søndenaa study of 322 patients, which reported a family history in 38% of patients, a sedentary occupation in 44%, local trauma or irritation preceding the condition in 34%, and 37% overweight against 50% at normal body weight (Søndenaa et al., 1995).

Commonly listed risk factors across reviews include male sex, a deep natal cleft, excess body hair, coarse or stiff hair, obesity, prolonged sitting, and a family history (ScienceDirect review).

Obesity deserves a caveat because the evidence is mixed. One study of 419 patients and 213 controls found mean BMI was 26.0 in patients versus 25.6 in controls, a difference that was not statistically significant, and concluded obesity alone is not an important cause (Cheng et al., 2001).

A later large case-control study calculated the independent risk of pilonidal disease as 1.56 for overweight people and 1.26 for obese people compared with those under a BMI of 25 (ScienceDirect).

Family history holds up across studies. A case-control study of teenagers found heredity significantly increased the odds of pilonidal disease (Özkan et al., 2016).

History: jeep disease

Pilonidal disease was first described by O.H. Mayo in 1833, and R.M. Hodges coined the term “pilonidal” (Latin for “nest of hair”) in 1880 (StatPearls, 2023).

The disease became famous during World War II. According to US Army publications, nearly 80,000 US soldiers were admitted and treated at US Army hospitals for pilonidal disease between 1941 and 1945 (StatPearls, 2023).

The more precise underlying figure was 77,637 soldiers admitted from 1942 to 1945 (JAMA Surgery). The familiar round “80,000” is a rounding of official US Army admission data, and it is best attributed to Army medical statistics rather than to any single author.

The nickname came from surgeon Louis A. Buie, who published a paper titled “Jeep disease (pilonidal disease of mechanized warfare)” in the Southern Medical Journal in 1944 (AccessEmergency Medicine). The theory at the time was that long, bumpy rides in jeeps irritated the tailbone area. Earlier, in 1940, the US Navy found pilonidal cysts caused more hospitalization than hernia or syphilis (AccessEmergency Medicine).

Healing was slow in that era. Contemporary reporting on Buie’s work noted a serviceman needed 60 to 90 days of healing time before returning to duty after standard excisional surgery, though Buie’s less aggressive technique cut average healing time to about 30 days (TIME, 1944).

One caution: a later re-analysis has questioned whether wartime conditions actually raised the incidence of the disease, so the classic “jeep caused it” story is best treated as historical context rather than settled fact.

Recurrence rates by procedure

Recurrence is where pilonidal statistics get most confusing, because the number depends heavily on which procedure was used and how long patients were followed.

The most useful source here is the work by Stauffer, Doll, and colleagues, who reviewed thousands of studies published between 1833 and 2017 and analyzed recurrence as a function of both procedure and follow-up time.

In their 2018 meta-analysis and merged-data analysis of 89,583 patients, recurrence after Karydakis and Bascom procedures was 0.2% at 12 months and 0.6% at 24 months. Recurrence after Limberg and Dufourmentel flap operations was 0.6% at 12 months and 1.8% at 24 months (Stauffer et al., 2018).

The same group found that primary midline closure, the historically common approach of stitching the wound straight down the middle, had recurrence as high as 67.9% at 240 months (20 years) of follow-up, and concluded this method should be abandoned (Stauffer et al., 2018).

Their 2019 follow-up study looked at recurrence by procedure and geography. At 12 months, recurrence ranged from 0.3% for Limberg/Dufourmentel and flap approaches up to 6.3% for incision and drainage. By 60 months, incision and drainage had the highest recurrence at 36.8%, and in the US data specifically it reached as high as 67.2% (Doll et al., 2019).

The practical picture by approach:

• Incision and drainage alone (for an acute abscess): recurrence rises steeply over time, reaching about 36.8% at 60 months. Another review reports recurrence for conventional incision and drainage varies from 11% to 67% (Doll et al., 2019; historical review).
  
• Excision with primary midline closure: high long-term recurrence, up to 67.9% at 20 years, and generally considered inferior. A single-institution series found a 42% recurrence rate (Stauffer et al., 2018; Iesalnieks et al., 2003).
  
• Excision with healing by secondary intention (left open): recurrence is lower than primary midline closure. A Cochrane review found recurrence was lower with open healing than with primary closure (Al-Khamis et al., 2010).
  
• Karydakis flap: George Karydakis’s own series of 141 patients reported about 4% recurrence. A trial in 200 military members found 4.6% recurrence for Karydakis versus 18.4% for primary midline closure (Karydakis, 1996; Bessa, 2009).
  
• Off-midline and flap procedures generally: consistently the lowest recurrence in the meta-analyses (Stauffer et al., 2018).
  
• Minimally invasive options (pit picking, EPSiT, laser): a 2023 systematic review in Techniques in Coloproctology found recurrence rates of 0 to 29% for these approaches. One prospective pit-picking study of 203 patients had 4.9% recurrence at a median 53-month follow-up (de Vries et al., 2023).
  

The most defensible summary: recurrence depends more on procedure type and follow-up length than on anything else. Off-midline flap procedures (Karydakis, Bascom, Limberg) have the lowest recurrence, primary midline closure has the highest and is falling out of favor, and minimally invasive techniques offer fast recovery but more variable recurrence.

Recovery and healing times

Healing time varies a lot by procedure, and the trade-off is usually faster healing against lower recurrence.

A large Cochrane review found wounds healed faster after primary (stitched) closure than after open healing, but recurrence was lower with open healing (Al-Khamis et al., 2010).

For open wounds left to heal by secondary intention, healing often takes weeks to months. One review notes the process can take up to 6 months, with case reports describing up to 2 years for large open wounds (Kann et al.).

A Swedish randomized trial gives clean head-to-head numbers: median wound healing time was 49 days for excision with midline suture, against 14 days for Karydakis flap surgery (Gavriilidis et al., 2019).

Minimally invasive procedures tend to have the fastest return to normal life. In the EPSiT and pit-picking literature, wound healing times ranged from about 3 to 47 days, and patients returned to daily activities within 1 to 9 days (de Vries et al., 2023).

If you’re recovering from surgery now, our practical guide covers how to sit after pilonidal cyst surgery.

Cost of treatment

US cost data for pilonidal treatment are limited and vary widely by procedure, facility, and insurance, so treat these as ballpark figures rather than precise numbers.

For simple incision and drainage of a pilonidal cyst, the average cash price is about $1,072 according to healthcare price-transparency data (Turquoise Health).

For surgical excision, Medicare’s procedure price lookup lists a Medicare-approved amount for simple excision of a pilonidal cyst or sinus (Medicare).

We are deliberately not citing the very wide ranges you’ll find on commercial cost-estimate blogs, because they aren’t traceable to a consistent methodology.

Malignancy risk

Cancer arising in a pilonidal cyst is very rare but real, and it only occurs in longstanding, chronic, or neglected disease. A case review summarizing the literature notes that the occurrence rate of malignant degeneration is often quoted at about 0.1% of pilonidal cyst cases, while cautioning that the true incidence is unknown, and reports that the most common histologic type is squamous cell carcinoma in 88% of cases (Malignant transformation case review). Fewer than 70 cases of malignancy arising in a pilonidal sinus have been published since the first, reported by Wolff in 1900 (Case review).

A note on numbers we left out

Some figures circulate widely online that we could not trace to a defensible primary source, so we excluded them:

• A specific percentage of all proctology visits or hospital admissions. Frequently implied in blog posts, but we could not find a clean primary source with a defensible US number. We included only the traceable England 2000 to 2001 admissions figure.
  
• “Average cost of definitive pilonidal surgery in the US is $2,000 to $10,000.” These ranges circulate on commercial cost-estimate blogs without a consistent methodology, so we cited only price-transparency data and Medicare’s published amount.
  
• Universal “time off work” day counts. These vary enormously by procedure and are only meaningful within a single study, so we reported them per study rather than as a headline average.
  
• The “1.1% incidence” figure that appears next to “26 per 100,000” in some documents. The two are not the same kind of measure. The 1.1% traces to a college-student screeni
  ng population, not the general population, so pairing them as interchangeable is misleading.
• The exact 80,000 WWII figure attributed to Buie’s 1944 paper. The round number is a rounding of official US Army admission data (the more precise figure is 77,637). Buie coined the term “jeep disease” but is not the source of the count.

Sources

1. Søndenaa K, et al. Patient characteristics and symptoms in chronic pilonidal sinus disease. Int J Colorectal Dis, 1995. https://pubmed.ncbi.nlm.nih.gov/7745322/
2. Nixon AT, Garza RF. Pilonidal Cyst and Sinus. StatPearls, 2023. https://www.ncbi.nlm.nih.gov/books/NBK557770/
3. Faurschou IK, et al. Time trends in incidence of pilonidal sinus disease 1996–2021: Danish cohort, 2024. https://pmc.ncbi.nlm.nih.gov/articles/PMC11683168/
4. Medscape. Pilonidal Cyst and Sinus: Background, Pathophysiology, Epidemiology. https://emedicine.medscape.com/article/788127-overview
5. Cleveland Clinic. Pilonidal Cyst. https://my.clevelandclinic.org/health/diseases/15400-pilonidal-disease
6. AccessEmergency Medicine. Pilonidal Abscess or Cyst Incision and Drainage. https://accessemergencymedicine.mhmedical.com/content.aspx?sectionid=45343751
7. JAMA Surgery. Pilonidal Cyst — Neither Pilonidal Nor Cyst. https://jamanetwork.com/journals/jamasurgery/fullarticle/556569
8. TIME. Medicine: Jeep Disease, 1944. https://time.com/archive/6598841/medicine-jeep-disease/
9. Stauffer VK, et al. Common surgical procedures in pilonidal sinus disease: meta-analysis. Sci Rep, 2018. https://www.nature.com/articles/s41598-018-20143-4
10. Doll D, et al. Impact of geography and surgical approach on recurrence. Sci Rep, 2019. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6805955/
11. Iesalnieks I, et al. Primary midline closure and recurrence, 2003. https://pubmed.ncbi.nlm.nih.gov/12748795/
12. Al-Khamis A, et al. Healing by primary versus secondary intention. Cochrane, 2010. https://pubmed.ncbi.nlm.nih.gov/20091589/
13. Karydakis GE. Pilonidal sinus: experience with the Karydakis flap. Br J Surg, 1996. https://pubmed.ncbi.nlm.nih.gov/8944470/
14. Bessa SS. Karydakis flap versus primary midline closure: 200 military members. Surg Today, 2009. https://pubmed.ncbi.nlm.nih.gov/19562445/
15. de Vries et al. Non-excisional techniques: systematic review. Tech Coloproctol, 2023. https://link.springer.com/article/10.1007/s10151-023-02870-7
16. Gavriilidis et al. Excision and midline suture versus Karydakis flap: RCT. https://pmc.ncbi.nlm.nih.gov/articles/PMC8932511/
17. Kann et al. Accelerated healing of complex open pilonidal wounds. https://pmc.ncbi.nlm.nih.gov/articles/PMC3635226/
18. Cheng et al. Lack of evidence that obesity is a cause of pilonidal sinus disease, 2001. https://pubmed.ncbi.nlm.nih.gov/11354323/
19. Sacrococcygeal pilonidal disease: analysis of risk factors. https://www.sciencedirect.com/science/article/pii/S180759322202484X
20. Risk Factors for Pilonidal Sinus Disease in Teenagers, 2016. https://pubmed.ncbi.nlm.nih.gov/27306225/
21. Chronic Pilonidal Cyst with Malignant Transformation: case report and review. https://pmc.ncbi.nlm.nih.gov/articles/PMC9018021/
22. Recurrent SCC arising in a neglected pilonidal sinus: case report and review. https://pmc.ncbi.nlm.nih.gov/articles/PMC3931603/
23. Pilonidal sinus: historical and current management modalities. https://pmc.ncbi.nlm.nih.gov/articles/PMC11129967/
24. Pilonidal disease: a new look at an old disease. ScienceDirect. https://www.sciencedirect.com/science/article/abs/pii/S1043148922000501
25. Turquoise Health. Prices for incision and drainage of pilonidal cyst. https://turquoise.health/services/incision-and-drainage-of-pilonidal-near-tailbone-c/
26. Medicare. Excision of pilonidal cyst or sinus; simple. https://www.medicare.gov/procedure-price-lookup/cost/11770/