What is a rectal prolapse?

A rectal prolapse occurs when the lowest part of the bowel telescopes on itself and protrudes out through the anus. 

What causes a rectal prolapse?

Rectal prolapse usually occurs as a result of pelvic floor weakness. It may be associated with other forms of prolapse in women such as uterine prolapse or bladder prolapse (cystocele). Childbirth may be a contributing factor to the development of pelvic floor weakness in women. Chronic straining may also be responsible for the development of some cases in men and women. Rarely malnutrition may play a part in the development of rectal prolapse. 

What are the symptoms of rectal prolapse?

Most patients are aware of a lump that comes down out of their bottom. Mostly the prolapse happens when patients have their bowels open but it can occur at other times. With time the prolapse may come down simply when a patient stands up or when they bend or lift. 

Sometimes the prolapse goes back (reduces) on its own on other occasions the patient may have to push it back themselves. 

Patients may also describe a discharge of mucus from the anus and sometimes bleeding as well. 

As the prolapse gets bigger it tends to stretch the muscle around the anus and patients may also have problems with leakage of stool. 

What investigations are required?

It is important to make sure that it is the prolapse that is causing the bowel problem. Most women will require some form of endoscopic examination of the bowel either by flexible sigmoidoscopy or colonoscopy to ensure that it is otherwise healthy. If there is a history of constipation the doctor may also recommend a transit study. 

Sometimes it can be difficult for the surgeon to see the prolapse in the clinic and a MRI proctogram, videoproctogram  or even an examination under anaesthetic may be helpful to confirm the diagnosis and assess the size of the prolapse. 

Most women will also have tests of their sphincter muscle function (anorectal physiology) and an endoanal ultrasound scan to look for any damage to the muscle. 

How is rectal prolapse treated?

For most patients with a rectal prolapse an operation will be recommended. 

There are two types of operation. In one type the prolapse is fixed from below (perineal approach) and in the other type the prolapse is pulled up from above (abdominal approach). 

There are two types of perineal operation that your surgeon will discuss with you. A Delormes operation for smaller prolapse or an Altemeier procedure, also known as perineal rectosigmoidectomy, for a larger prolapse.  

 The abdominal procedures can often be carried out as laparoscopic, or keyhole procedures. A posterior rectopexy is the most common technique used. 

Generally the operations carried out abdominally give better long term results but are more ‘invasive’ procedures. The perineal operations are usually recommended for older patients who may be less fit.