Future Tense

The Most Important Prosthetic Created by Science Helps You Pee

A prosthetic bladder: more valuable than a toilet with gold-plated accessories

Photo by ROSLAN RAHMAN/AFP/Getty Images

When you read about new prosthetics, it’s usually about fancy robotic arms, legs, and brain-computer interfaces. And while those are all exciting technologies, there’s this whole other world of prosthetics with the potential to dramatically improve the lives of quadriplegics and paraplegics. I refer, of course, to bladder control. Most of us take the ability to urinate for granted, but doing so requires a network of firing nerves, contracting muscles, and communication with the brain. Unfortunately, the nerves that control bladder (and bowel) functions are near the bottom of the spine—which means those with traumatic spine injury usually suffer from a severed connection. Without constant management, urine can back up into the kidneys or empty at unpredictable times. Other woes include bladder and kidney damage, life-threatening infection, and bladder cancer. But there may soon be a new method for achieving better bladder control, according to a study published in this month’s Science Translational Medicine. Scientists have been working on a neuroprosthesis that would tap into the nervous system and interpret electrical messages from the bladder. One day, these messages may be able to set off a buzzer letting the user know that the bladder is full and even allow her to empty it at the touch of a button.   There are currently other methods for regulating bladder function, but they leave a lot to be desired. Catheters are probably the simplest method, but they often fail to drain the bladder completely, and lingering urine becomes a breeding ground for bacteria. Another method involves the implantation of a “sacral anterior root stimulator.” This allows the patient control over the bladder but does not provide any indication of when the bladder is full—you just have to keep emptying it every so often. The implant can also have unfortunate side effects like weakening of the pelvic floor muscles and the loss of sexual functions. (Many people suffering complete paralysis can still have sex for pleasure or procreation, an ability that no one should have to sacrifice for the sake of better bladder control.) According to Daniel Chew from the Cambridge Centre for Brain Repair and one of the study’s lead authors, his team has had great success testing their neuroprosthesis device on rats, but it could be some time yet before it’s ready for human use. They will need to miniaturize the equipment and make it wireless before submitting the product for extensive human trials. However, their achievement could lay the groundwork for many other uses of neuroprosthetics throughout the human body.   “That is the beauty of neuroprosthetics,” Chew told me in an email. “The principle can be applied to the whole body, as all organs of the body are controlled by peripheral nerves. Refinement in neuroprosthetics may one day help treat many diseases such as hypertension, asthma, diabetes, and inflammation.” And such devices wouldn’t just benefit those with spine injuries. Sufferers of multiple sclerosis and ALS (or Lou Gehrig’s Disease) would also profit from better bladder control. A friend whose husband has ALS said he suffers from urinary tract infections on a monthly basis and any technology that could both empty the bladder and prevent infection would be amazing. If this were a traditional article about prosthetics, this would probably be the part where I’d embed a video of the robot arm/leg/exoskeleton at work, and we’d all marvel at how amazing science is. Well, I’m sorry to say there’s no futuristic bladder video. But that doesn’t make Chew’s research any less crucial for the millions who struggle with bladder issues every day. Think about that the next time you run to the bathroom.