Why Do I Keep Getting a Cyst Near My Tailbone?

Introduction

You went through the pain of a pilonidal abscess, had it drained at hospital or your doctor's rooms, and were told things were sorted — only to find yourself back in the same situation a few months later. This is incredibly common. Studies suggest pilonidal abscesses come back in roughly 40 to 50 per cent of people who only have drainage, and many go on to develop a chronic pattern of repeated flare-ups over months or years.

Understanding why this happens is important — and hopefully reassuring. Recurrence is not bad luck, and it does not mean anything went wrong with your treatment. It is what predictably happens when only the acute abscess is dealt with, without addressing the underlying sinus tunnels that caused it in the first place.

This page explains the mechanism behind recurrence, the factors that keep the cycle going, and what definitive treatment looks like for people who are ready to put an end to the pattern.

Why pilonidal cysts come back — the hair-entry cycle

To understand why it keeps coming back, it helps to understand how the problem starts in the first place. Loose hairs — usually from the buttocks or lower back — get pushed into the skin of the crease between your buttock cheeks by friction, pressure, and movement. Hair does not belong under the skin; it is forced there, much like a splinter.

Once a hair is under the skin, your body treats it as something foreign. Inflammation builds around it, and over time a small cavity lined with tissue develops — this is the pilonidal sinus tract (the tunnel). The tract typically has one or more small openings, called pits, visible on the skin surface. These pits are the entry points where more hairs keep getting pushed in.

Here is the key problem: draining an abscess empties the infected pocket, but does not remove the sinus tunnels. After drainage, the pits and passages are still there. Hairs keep entering through those same openings, the tunnel fills back up with debris and bacteria, and — given enough time — another abscess forms. This cycle can repeat indefinitely without treatment that actually addresses the tunnels themselves.

Symptoms of recurrent pilonidal disease

People with recurrent pilonidal disease often notice a predictable pattern. There is a period of apparent healing after each drainage episode — sometimes weeks, sometimes months — then increasing discomfort, and eventually another painful flare-up. Over time in chronic disease, the gaps between episodes tend to get shorter and the flare-ups more frequent.

Signs that your disease has moved into a chronic pattern include:

• Several small pit openings visible in or near the crease
• A persistent dull ache that never fully settles between acute episodes
• Intermittent discharge of blood-stained or foul-smelling fluid, even when things are not acutely infected
• A firm, cord-like area you can feel under the skin
• More than one or two abscess episodes in the same area

If any of this sounds familiar, it is worth seeing a colorectal surgeon for a proper assessment. Waiting for things to resolve on their own is unlikely to work at this stage — but effective treatment is available.

Causes and risk factors that drive recurrence

Several things make some people more prone to recurrence than others. Understanding your own risk factors is also useful because it helps guide the lifestyle changes that reduce the chance of the problem coming back after definitive treatment.

• Prolonged sitting: Extended sitting — for work, study, or travel — generates continuous friction and pressure in the crease, repeatedly pushing loose hairs into existing pits and creating new entry points. This is probably the most important modifiable risk factor.
• Thick or coarse body hair: People with thick, dark, or curly hair shed more in the crease area and have hair that is more likely to penetrate the skin because of its shape and stiffness. Hair type is largely genetic.
• Overweight or obesity: Excess weight deepens the crease and increases skin-to-skin contact and friction, creating conditions where hair gets trapped more easily.
• Sweating: Moisture in the crease softens the skin, lowering its resistance to hair penetration. People who sweat heavily or do physically demanding work are at higher risk.
• Incomplete first treatment: Simple drainage — where only the pus is released without removing the sinus tunnels — is a major driver of recurrence. Unfortunately, this is the most common first treatment people receive.
• Previous wound breakdown: If a surgical wound from a prior treatment broke down or did not heal fully, residual sinus tissue may remain and become the starting point of the next episode.

When to worry — red flags

Beyond acute episodes, the following are signs that you need a specialist review sooner rather than later:

• Three or more episodes of abscess formation in the same area
• Persistent discharge between episodes that is not resolving
• A wound from prior surgery that has not healed after six to eight weeks
• Multiple sinus openings — this suggests extensive tract disease that may require a more complex surgical approach
• Any change in the character of discharge (e.g., bleeding from the sinus without infection) — though rare, a specialist should assess this

Lifestyle modifications to reduce recurrence

Lifestyle changes cannot cure established sinus tracts, but they are an important part of reducing recurrence after definitive treatment and managing the condition in early or mild disease. Think of these as long-term maintenance rather than a cure.

Treatment options for recurrent disease

Once recurrence has occurred — or once it becomes clear that sinus tracts have formed — lifestyle changes and drainage alone are insufficient. Definitive surgical treatment is required to remove or destroy the sinus tracts and allow proper healing. The good news is that several effective options exist, ranging from minimally invasive to more extensive procedures.

Excision and primary closure involves surgically removing the sinus tracts and pits and stitching the wound closed. When performed correctly with meticulous technique — particularly using an off-midline closure — this approach achieves very good long-term results.

Flap procedures (Karydakis, Limberg) are used for extensive or recurrent disease, particularly where previous simpler surgery has failed. These techniques use a flap of nearby skin to reconstruct the natal cleft, deliberately flattening it to reduce the risk of future hair entry. They carry a higher technical complexity but very low recurrence rates in appropriate patients.

When surgery is needed

Surgery is recommended for anyone who has experienced more than one acute pilonidal abscess, who has established chronic sinus tracts, or whose symptoms are significantly affecting their quality of life or ability to work. Waiting for repeated episodes to "burn themselves out" is rarely a successful strategy — disease tends to progress, tracts expand, and the eventual required surgery becomes more complex.

Mr Nguyen will discuss your history, examine the extent of the disease, and recommend the most appropriate surgical approach for your specific situation. Factors including the number and position of sinus openings, your body habitus, your work and recovery time constraints, and any prior surgical history will all influence the recommendation.

After definitive surgery, whether hair removal is recommended depends on individual patient and disease factors — it is not a routine blanket instruction. Where it is advised, laser hair removal is the preferred approach. Mr Nguyen will discuss this with you at consultation.

Frequently asked questions