Definition and overview

Hernias occur when an internal organ or tissue pushes through a weak spot in the muscle, or tissue wall that usually holds it in place. Perineal hernias are generally considered a rare complication of extensive pelvic surgery and as such tend to be underreported and poorly studied.¹ It is described as a protrusion of fluid, fat, part of the intestine, or any other contents of the abdominal cavity through the perineum.² These can be pushed out through a congenital defect or caused by an acquired defect, for example during surgery.² A hernia may occur in the front or back of the perineal muscles, which are found between your genitals and anus.² 

Acquired perineal hernia can be classified as primary or secondary.² Primary acquired perineal hernias are linked to increased abdominal pressure and occur five times more frequently in individuals with broader pelvic anatomy, such as those who have experienced pregnancy and childbirth.^2,3 During these events, the pelvic floor is often weakened, contributing to a higher risk of developing these hernias.² Secondarily acquired hernias are ‘incisional’ hernias, meaning that they are associated with extensive pelvic operations.² 

Their management can be challenging and there are not many prevention strategies, particularly if the defect is congenital, however, there is a wide range of treatment options available typically including minimally invasive surgical options.¹

Symptoms and diagnosis

Common signs and symptoms

Symptoms of a perineal hernia are heavily dependent on the location and severity.³ In an anterior perineal hernia (in front of the perineal muscles), the typical clinical symptom is a prolapse around the labia, which is when pelvic muscles cannot effectively support the surrounding structures causing one or more pelvic organs to ‘slip’ from their normal position.³ For a posterior hernia (behind the perineal muscles), the typical clinical presentation is a bulging on one side of the gluteal or perineal region.³ 

The general symptoms of a perineal hernia, observable in most if not all cases are pain and discomfort.⁴ Often a distinct bulge would also be found during a physical examination.⁴ Furthermore, the patient could be affected with bowel obstruction strangulation, and even skin erosion.²

Diagnostic procedures: physical examination and imaging

On presentation, a patient would be physically examined and a patient history would be acquired to determine a potential cause of the symptoms and decide on the next steps of treatment and management.³ A clinician would expect to observe swelling and a distinct mass in the perineal area confirming the suspicion of a hernia.³ This can also be supplemented by external ultrasonography (ultrasound), transvaginal ultrasonography, or even computerized tomography (CT) or magnetic resonance imaging (MRI).³ An upright position during examination allows a clinician to observe protruding bowel segments and anatomic identification.³ A perineal hernia can often be mistaken for other conditions, such as cysts, rectal prolapse, or benign tumours, such as lipomas.³ 

Treatment options

The progression of symptoms such as pain, intestinal obstruction, and difficulty urinating, necessitate management, typically through surgical intervention.² This can be approached in several ways, through transabdominal (passing through the abdomen), perineal, or combined abdominoperineal methods.² Depending on the severity, site, and size, the muscle defect can be mended with direct stitches or by using a graft or synthetic mesh to secure more problematic defects.² The treatment should be individualized to each case, as each patient will benefit from different approaches, due to their personal specifications.³  

During a perineal approach, an incision is made directly over the hernia defect and corrected.⁵ However, if the surgeon is unable to reduce the hernia using this method, a combined procedure may be necessary.⁵ The abdominal approach can be open or minimally invasive, to allow for an abdominal exploration.⁵ This allows for the herniated contents to be retracted and for the defect to be amended.⁵ 

For simple repairs, direct amendments with simple stitching are considered an effective option, however, it should be used with care, due to potential relapse.³ However, in most cases the pelvic floor is severely deficient and requires autologous or prosthetic material to repair the damage.³ One largely favoured option is using non-absorbable mesh for the repair, as this is often very durable and recurrence-free.³ The surgery site can be accessed using transabdominal, transperineal, abdominoperineal, or laparoscopic approaches.³ The abdominal approach combined with a synthetic mesh repair seems to be associated with lower relapse rates compared to other techniques.¹ The perineal and abdominal approaches seem to be safe with similar rates of recurrence, whilst the combined approach requires more evidence despite it being seemingly promising.¹ Generally, no particular technique is superior, and each case should be examined on an individual basis, considering relevant anatomic and patient factors. 

During minimally disruptive cases of perineal hernias, symptoms can be managed and the patient can be monitored consistently. This could include regular scans and physical examinations, however, certain clothing can also provide the support needed to alleviate some of the symptoms. 

Complications and prognosis

Potential complications

As treatment for perineal hernia can be quite invasive, several associated complications could occur. There is a chance of developing a postoperative wound infection, which could lead to more serious problems even becoming fatal.⁶ Furthermore, synthetic material, such as the mesh used in some surgical approaches, could lead to rejection.⁶ There also remains a chance for recurrence even with surgical amendments, and this is particularly noticeable following an abdominoperineal approach, regardless of what mesh type was used, especially if the underlying cause isn’t adequately addressed or if there are complications during the initial repair.⁶ 

Long-term prognosis and management

The prognosis for hernias largely depends on several factors, including the type of hernia, its size, the individual's overall health, and whether prompt treatment is sought. Patients who develop a perineal hernia may experience discomfort performing daily tasks and would be afflicted with urogenital dysfunction.⁶ This can significantly affect their quality of life with regard to many domains.⁶ They can become a debilitating issue, particularly since in addition to the pain and associated symptoms, there is also a cosmetic disfiguring of the affected area.⁵ Moreover, even without acute complications, some hernias can cause ongoing discomfort or pain, affecting the person's quality of life and they can increase in size over time, making them more challenging to repair and increasing the risk of complications.

Causes and risk factors

Potential risk factors include age, since perineal hernias increase in incidence as patients reach the age of 60.⁷ The most common age for developing a perineal hernia is between 40 and 60 years.³ Obesity as well as gender could also affect the chances of developing a hernia.⁷ Additionally certain medical conditions and treatments could also be linked to an increased risk of developing a perineal hernia, including diabetes, chronic conditions that cause fluid build-up, chemoradiotherapy for cancer treatment, certain abdominal surgeries, and even variations in small intestine length.⁷ 

Prevention strategies

Prevention is greatly important when it comes to reducing the incidence of perineal hernia, however, particular prevention strategies are still yet to be researched thoroughly.⁷ During an abdominal surgery, careful closure of each layer could significantly reduce the risk of hernia formation.⁷ Furthermore, the use of supportive undergarments could support the pelvic area, providing symptomatic relief and preventing worsening.⁷

Summary 

Perineal hernias occur when part of the intestine, or other structure within the abdominal cavity bulges through the perineal muscle. This affects the area surrounding the anal or genital regions. It can be caused by complications following surgery, however, it could also be linked to the presence of a congenital defect. Similarly to other types of hernia, it can be indicated by a visible protrusion, alongside pain and discomfort. It can also be linked to other issues such as bowel obstruction or urogenital dysfunction, affecting daily function. 

It is treated or managed depending on the patient’s history, anatomical features, and severity of the condition. In less severe cases it is typically managed through regular tests and observation, particularly when the patient is mostly asymptomatic. Otherwise, surgery may be recommended, which encompasses a large range of techniques and approaches. Typically this would involve stabilizing the pelvic floor with biological or synthetic mesh, to prevent relapse. 

Most individuals who undergo timely and appropriate treatment for hernias can expect a good prognosis. Following the surgeon's post-operative instructions, maintaining a healthy lifestyle, and addressing any underlying conditions that contributed to the hernia can significantly improve the prognosis and reduce the risk of recurrence.