Introduction

A vasectomy is a more definitive and permanent form of contraception in males that results in sterilisation. It is the most common route of sterilisation in men, with a success rate of 98%.¹ As vasectomies are invasive surgical procedures, the resulting impact can manifest as lasting pain in the male genitalia, and this is called Post Vasectomy Pain Syndrome (PVPS). In simpler terms, PVPS is described as the onset of persistent pain in the genitals after a vasectomy and is typically characterised by symptoms such as the potential loss of erectile function, tender genitalia, pain during sexual contact, and lasting groin pain. 

PVPS is said to be caused by damage to the spermatic cord (collection of nerves, blood vessels, and tubes that carry sperm from the testicles), leading to nerve compression and inflammation.¹ The discomfort might be continuous or occasional, and it may start right away or years after a vasectomy.¹ A meta-analysis reports the incidence of PVPS in approximately 1% - 6% of men who undergo a vasectomy.² Therefore, timely medical intervention is crucial in maintaining a good quality of life. 

Pathophysiology

The pathophysiology of PVPS is uncertain. There is no definitive cause; however, there are a number of mechanisms that can contribute to PVPS. Differential diagnoses are often made; therefore, it is important to note that PVPS is generally diagnosed by exclusion. 

Mechanical forces

The general principle of a vasectomy is to prevent the entry of sperm into the ejaculate by severing the vas deferens, and this is achieved through surgical means. Therefore, while vasectomies can be quite straightforward, they can be performed in two ways. The severed ends of the vas deferens are left exposed when it is cut during an open-ended vasectomy.³ A closed-ended vasectomy, however, is characterised by the use of clips and seals to close off the ends of the severed vas deferens, consequently stopping the entry of sperm into the ejaculate.³ 

Quite early after surgery, a granuloma or a chronic inflammatory signalling network (ongoing irritation in the body’s immune system) may emerge as a result of an open-ended vasectomy.³ However, the majority of symptoms in PVPS occur after a closed-ended vasectomy is performed, with the onset of such symptoms often being quite late.³ Early late-onset changes are primarily due to the increase in luminal pressure (buildup of pressure inside the sperm-carrying tubes)  and luminal phagocytosis (immune cells cleaning up trapped or leaking sperm inside those tubes).³ The more intermediate effects are seen in the form of immune cell infiltration, a phenomenon that is absent prior to vasectomy. Other changes occur in the form of epithelial cell junction breakdowns.³ 

Sperm granulomas and vasitis nodosa are two of the most common post-operative symptoms that contribute to PVPS.³ In simpler terms, a sperm granuloma is a nodule of sperm material that occurs post-vasectomy. A vasitis nodosa is a nodule of cells of the vas deferens that are formed as a result of the entry of fluid and sperm into the vas deferens wall. Sperm granulomas and vasitis nodosa are quite similar in nature, therefore, it is important to perform histological analyses to make a definitive diagnosis.³ 

Inflammation

The immune system also plays an important role in contributing to the pathology of PVPS. The majority of patients who have undergone a vasectomy (~ 60% - 70%) exhibit antisperm antibodies (proteins made by the immune system that mistakenly attack the body’s own sperm).⁴ Antisperm antibodies can result in sperm agglutination (the result of sperm cells sticking to each other and forming clumps) and hamper the ability of sperm to fertilise an egg. The presence of agglutination was reported to increase up to 60% - 76% approximately four to eight years after a vasectomy. Inflammatory signals can also trigger nerve fibrosis and lymphocytic infiltration, which can contribute to the chronic pain observed in PVPS.⁴ 

Risk factors and diagnosis

As the pathophysiology of PVPS is fairly uncertain and is not particularly influenced by age or lifestyle, there are no major specific physiological conditions that contribute to this condition. Nonetheless, men who have autoimmune diseases or who have previously had groin discomfort may be more likely to develop PVPS.¹ A history of hernia repair and kidney stones may also play a role.³

PVPS can be differentially diagnosed as neuropathic pain, testicular torsion, infection, or prostatitis due to the prominent presence of groin pain.^1,3 Therefore, an accurate diagnosis is of utmost importance for pain relief. It is recommended to obtain a urine analysis as well as cultures of urine and semen to rule out infection.^1,3 Every patient who has persistent testicular discomfort should also have a colour Doppler flowmetry ultrasound. Doppler flowmetry allows for the assessment of blood flow and vascular anatomy, and can therefore help detect and analyse post-vasectomy related changes. Part of a comprehensive evaluation also includes performing spermatic cord block injections, which contain 1% lidocaine, to isolate the cause of pain in the scrotum and its nerves.¹ An MRI may also be performed to rule out other neurological factors. 

In the event of inconclusive laboratory findings, it is also important to consider performing a psychological evaluation, as some patients reported symptoms of major depressive disorder.^1,3,4  This can account for a well-rounded approach to treatment and pain management.

Treatment and management 

A multimodal treatment plan is often used to target PVPS, with a focus on nonsurgical treatments for pain relief. Pharmacological interventions primarily include nonsteroidal anti-inflammatory drugs (NSAIDs) and/or tricyclic antidepressants, both of which are also used as common avenues of treatment for neuropathic pain.¹ This treatment plan may also involve the participation of urologists, psychiatrists, and anaesthesiologists.¹ 

While the aforementioned are all viable and often necessary alternatives, their effects are generally temporary. This triggers the need for surgical interventions such as granuloma excision, denervation, epididymectomy, vasectomy reversal, and in severe cases, orchiectomy. 

Excision of sperm granulomas

Excision of sperm granulomas is often the selected treatment of choice when the patient presents with noticeable bumps after physical examination.¹ This can reduce localised inflammation and any congestion caused by the granulomas.⁴

Denervation

Denervation is achieved using microsurgical methods. The effect of spermatic cord denervation was studied in patients who had histories of being successfully treated for pain using cord blockers.⁴ Approximately 76% of these men reported complete pain relief after denervation.⁴

Epididymectomy

An epididymectomy is the surgical removal of the epididymis, which is responsible for the maturation and storage of sperm. A study reported epididymectomy-induced pain relief in 50% of individuals with post-vasectomy pain.⁵ The positive impact of epididymectomies on PVPS was also observed in a study where approximately 87% of patients reported almost immediate and sustained pain relief.⁶ 

Vasectomy reversal

A vasectomy reversal is also considered a good surgical alternative, with around 93% of patients exhibiting relief from pain.⁷ These patients also reported an improvement in their quality of life. Additionally, 82% of participants in another study observed significant improvements in pain relief after a vasectomy reversal.⁸

Orchiectomy

An orchiectomy is performed in severe cases, following failure to achieve pain relief using the methods listed above. It is important to bear in mind that while effective, there are significant physiological and psychological risks associated with this line of treatment. Therefore, a thorough counselling session must be conducted to inform individuals about all aspects of treatment.^1,4 

Summary 

Post Vasectomy Pain Syndrome (PVPS) is a chronic pain condition that can develop after vasectomy. The underlying causes include several factors such as nerve damage, inflammation, pressure buildup, and immune reactions like antisperm antibody formation. Treatment includes the usage of NSAIDs and antidepressants as well as surgical options like sperm granuloma excision, epididymectomy, vasectomy reversal, or even orchiectomy. While research has identified different strategies to alleviate post-vasectomy-associated pain, a thorough evaluation of symptoms and medical histories is crucial to prevent the need for last-resort treatment strategies. PVPS can be treated and managed effectively if symptoms are accurately analysed.