Peyronie's Disease vs Normal Curvature

Overview

Peyronie’s disease, also known as penile curvature, is a condition that causes the penis to curve significantly when erect. It is caused due to the build-up of scar tissue, known as plaques, under the skin which affects how the tissue moves during an erection. The result is erections that can be painful and can make intercourse difficult. This disease is common, with an estimated 1 in 100 males over 18 being affected, though some estimates place this as high as 1 in 10.^1,2 The incidence of the disease increases with age, with those over 40 being particularly affected. This article aims to address concerns and questions by providing an in-depth look at Peyronie’s disease, how it compares to normal curvature and what possible treatments can take place.

Before diving into this article it should be noted that the plaques in this disease are benign and pose no real threat to health apart from discomfort. Essentially, curvature of the penis is normal, but if pain occurs please contact your GP or sexual health clinic.

What is Peyronie's disease?

Peyronie’s disease is a condition which affects the penis. It is caused by a build-up of plaque underneath the skin of the penis, which changes its curvature. This plaque forms in the thick elastic membrane layer of the penis called the tunica albuginea, which is involved with maintaining erections. This is a layer that extends the length of the penis and the male urethra. Therefore, the plaque can form anywhere on the penis, causing it to curve in a number of directions. The curvature is usually only apparent during erections.³

The plaque is able to cause curving in the penis due to the plaque’s inflexibility. When an erection occurs, the plaque pulls on the surrounding tissue, which causes the overall penis to curve or bend. As the whole penis tissue curves in an unnatural way, it can cause pain or discomfort for an individual. The build-up of this plaque also occurs in two stages: acute and chronic.²

Acute stage: 

This is the initial stage in which the scar tissue builds up, forming the plaque. It can last up to 18 months. The key features of this stage include:

• Plaque formation begins due to inflammation.
• The penis starts to curve as plaque builds up.
• The penis can start to hurt, with or without an erection.³

Chronic stage:

This follows the acute stage after the plaque has formed. This stage is reached at 12 to 18 months after onset and has a different set of distinctive features:

• The plaque has solidified, meaning it will not get worse. Therefore, the curvature in the penis does not get worse.
• The pain caused by the disease may lessen.
• Erectile dysfunction may develop.³

Once the chronic stage has been met, the penis curvature will be set until treatment is undertaken. We will review treatment options further in this article.

Symptoms of Peyronie’s disease

• A plaque in the shaft of the penis. This can feel like a hard area or lump in the penis. It is very rare to develop more than one plaque. The penis can also look misshapen due to the presence of the plaque, usually in an hourglass shape.
• A characteristic curve in the penis when it is erect. 
• Pain in the penis when it is erect. However, pain can occur when it is not erect as well. 
• Change in the girth or length of the penis.

If you notice any of these symptoms, you might be suffering from Peyronie’s disease and it is advised that you contact a GP or a sexual health clinic. 

Causes and Risk Factors of Peyronie’s disease

There are several causes of this disease related to potential injury of the penis tissue. These include vigorous sexual intercourse, non-sexual activities that can cause micro-injuries, certain connective tissue or autoimmune disorders, and prostrate cancer treatment or surgery. There are also risk factors for Peyronie’s disease such as age, family history of the disease, and suffering from diabetes with erectile dysfunction.

Vigorous sexual intercourse or non-sexual activities such as certain sports can cause micro-injuries to the penis. If enough of these micro-injuries occur, an inflammatory response will be triggered. This can cause the plaque which leads to Peyronie’s disease.³

Certain connective tissues and autoimmune diseases can also increase the risk of Peyronie’s disease. Connective tissue refers to the tissue that supports and protects the rest of the tissue in your body. There are three known diseases of the connective tissue that increase the risk of Peyronie’s. This includes Dupuytren’s disease, plantar fasciitis, and scleroderma. In addition, there are three autoimmune diseases that are also known to increase the risk of Peyronie’s: Systemic lupus erythematosus, Sjogren’s syndrome, and Behcet’s disease.³

Other conditions can also increase the risk of Peyronie’s. Prostate cancer treatment can increase the chance of Peyronie’s due to an increased chance of erectile dysfunction.⁴ A family history will increase the risk of Peyronie’s, and it is believed the disease may run in some families. Diabetes can also increase the risk of developing Peyronie’s up to 4 or 5 times higher than average.⁵ Finally, ageing can also increase the risk due to tissues becoming damaged more easily and healing less effectively.

Complications

Apart from the curved penis, there are also complications that can arise from Peyronie’s disease. These complications can include:

• Difficulty or inability to have sexual intercourse due to pain or curvature of the penis
• Erectile dysfunction 
• Mental health issues such as anxiety, depression, and emotional stress can occur due to concerns over sexual abilities or the appearance of the penis
• Shortening of the penis

Peyronie’s disease vs normal curvature

The main symptom of Peyronie’s disease is the curving of the penis. In some people, it can be easily noticed, but in other people, it might be more subtle and therefore harder to diagnose. This leads us to question what a normal curvature for the penis is.

What is considered normal curvature?

Normal curvature is hard to define for a penis. This is because there is no standard penis shape. There are lots of different shapes and sizes out there, so defining “normal” curvature is hard. It is also normal for a penis to curve slightly in any direction. If your penis is curved and you experience no pain, then the curvature is most likely normal. However, if you do experience pain, then you may have Peyronie’s disease. 

Treatments

Treatment for Peyronie’s disease revolves around reducing pain for an individual and returning the penis to a straight or close-to-straight shape. However, not all people with Peyronie’s will need treatment, as the symptoms are often quite mild. If there are only small plaques and there is no pain or inhibition to intercourse, then treatment will most likely be not prescribed. If you do need treatment, you can be prescribed medication or undergo a surgical procedure.

Medication

Medication to treat Peyronie’s includes injections and non-drug medical therapies. Injections involve administering medication directly into the plaques by a process called intralesional injections. These are usually done in the acute phase and can utilise 3 different compounds. Collagenase is an enzyme which breaks down the substances which form the plaques and is the only FDA-approved drug. Other injection medicines include verapamil and interferon alpha 2b.⁶

There are no oral medicines for Peyronie’s disease, but there are some theories about potassium para-aminobenzoate being effective. This compound is used in the treatment of Dupuytren's disease and may reduce plaque size. However, it has no effect on penile curvature. Other non-drug therapies are still being investigated to determine their efficacy. These include mechanical traction, vacuum devices, or shockwave therapy.⁶

Surgical treatments

If there is no improvement in symptoms, or erections and intercourse are extremely painful, then a doctor might recommend surgery. This has to be completed in the chronic phase when the plaque has stabilised. It should be noted that complications can occur from surgery and that it may not correct all effects of Peyronie’s such as penis shortening. There are three main types of surgery.

• Grafting- this surgery involves removing the plaque from the penis and replacing it with tissue. This tissue can be sourced from the body such as veins or skin from the leg, but can also be sourced from a laboratory or organ donor. This will straighten the penis and restore some length. However, some men may experience numbness or erectile dysfunction.

• Plication- this surgery is done by pinching or removing tissue in the tunica albuginea on the opposite side of the plaque. This counteracts the effects of the plaque to straighten the penis. This can be preferred as it is less likely to cause numbness or erectile dysfunction but cannot restore length or girth lost. It may actually shorten the penis. 

• Device implantation- this surgery is mainly used in treating erectile dysfunction. A device is inserted into the penis which can produce and maintain an erection. An example device is an inflatable implant which inflates for an erection and deflates when flaccid. These devices can straighten the penis but if it does not, it can be combined with the other two surgeries.

Summary

Peyronie’s disease is a condition that can affect men by causing the penis to curve. It is caused by the formation of plaques from several sources, such as an autoimmune disorder. This curvature can lead to several problems such as erectile dysfunction or difficulty with intercourse. However, there are treatments available for the disorder such as injection medications or surgery. These bring their own risks but will hopefully straighten the penis.

Takeaway

A curvature ranging between five to 30 degrees is considered within the normal spectrum. However, when the bend becomes more pronounced, exceeding 30 degrees, it could be indicative of Peyronie's disease. This condition is characterized by fibrous scar tissue inside the penis, leading to painful erections. An urologist can provide an accurate assessment, differentiate between natural curvature and Peyronie's disease, and recommend appropriate treatment options if needed.