Biofeedback therapy is a mind-body technique that teaches individuals to gain conscious control over typically involuntary bodily functions. This non-invasive approach uses specialized equipment to provide real-time information about physiological processes. For individuals with chronic constipation, biofeedback offers a targeted treatment to address issues interfering with normal bowel movements.
Mechanisms of Biofeedback for Constipation
The core principle of biofeedback involves using sensors to provide immediate feedback on physiological processes like muscle activity or pressure. This information helps individuals learn to consciously control these functions, particularly the coordinated actions of the pelvic floor muscles, anal sphincter, and rectum. Many people with chronic constipation experience dyssynergic defecation, also called anismus or pelvic floor dyssynergia. This condition involves the inability to relax or the paradoxical contraction of the pelvic floor muscles during an attempted bowel movement. Biofeedback helps retrain the coordination of these muscles for effective stool expulsion.
Specific types of biofeedback target different aspects of defecation. Electromyography (EMG) biofeedback monitors muscle activity, showing patients how their pelvic floor muscles are contracting or relaxing. Manometry uses a small probe to measure pressure changes in the rectum and anal canal, providing feedback on sphincter relaxation and propulsive forces. Balloon expulsion training involves inserting a small balloon into the rectum, which the patient learns to expel by coordinating abdominal pushing with pelvic floor relaxation, improving overall coordination.
Types of Constipation Responsive to Biofeedback
Biofeedback therapy is primarily indicated and most effective for specific forms of chronic constipation, particularly those related to pelvic floor dysfunction. This includes dyssynergic defecation, as described previously. It also benefits individuals with rectal hyposensitivity, a condition where the urge to defecate is not felt until significant stool retention occurs. While it may improve normal transit constipation, biofeedback is not helpful for isolated slow transit constipation, where bowel contents move too slowly through the digestive tract.
What Happens During a Biofeedback Session
A biofeedback session for constipation begins with an initial assessment, including a review of the patient’s bowel history and current medications. Sensors are used to provide real-time feedback. These can include surface electrodes on the perineum or buttocks to monitor muscle activity, or a small, flexible rectal probe to measure pressure changes in the anal sphincter and rectum. The rectal probe is usually 4-6 millimeters wide and inserted no deeper than 10 centimeters.
Patients receive visual or auditory feedback on a computer screen, showing their muscle activity or pressure readings as they perform exercises. For instance, they might watch an object on the screen move as they push or relax their abdominal and pelvic floor muscles. The therapist guides the patient, providing instructions and encouraging correct responses, such as practicing proper relaxation, bearing down effectively, or coordinating muscle movements.
A session lasts 45 to 60 minutes. The number of sessions varies, but ranges from 2 to 5, spaced one to two weeks apart. Consistent home practice is encouraged to reinforce learned techniques.
Outcomes of Biofeedback Therapy
Biofeedback therapy shows effectiveness in treating certain types of chronic constipation, particularly dyssynergic defecation. Randomized controlled trials demonstrate its superiority over standard treatments like laxatives or sham therapy for this condition. For patients with dyssynergic defecation, success rates of 70% to 86% have been reported, with improvement in bowel symptoms and correction of defecation dynamics.
A study involving patients with pelvic floor dysfunction showed that 71% of patients reported a satisfactory response after six months of biofeedback, with improvements maintained for up to two years. While individual results can vary, some studies indicate complete success, defined as three or more spontaneous bowel movements per week without laxatives, in about 35% of patients, with partial success in an additional 13%. Completing five or more sessions significantly improves the success rate, with about 63% of patients achieving full success.