A JJ stent (also called a double-J stent) is a thin, flexible tube placed inside the ureter, the narrow passage that carries urine from a kidney down to the bladder. It holds the ureter open so urine can drain freely when something is blocking or narrowing that path. The name comes from the tube’s shape: both ends curl into a “J” to anchor the stent in place, with one curl sitting in the kidney and the other in the bladder.
How It Works
The stent is essentially a hollow tube with holes along its length. Each curled end has one hole at the tip and four side holes, allowing urine to flow through the tube and around it. The J-shaped curls prevent the stent from sliding out of position, keeping one end secured inside the kidney’s collecting area and the other inside the bladder. Most JJ stents are made from flexible polymers designed to stay comfortable inside the body for weeks to months.
Why Doctors Place One
The core purpose is relieving or preventing a blockage in the ureter. That blockage might come from a kidney stone too large to pass on its own, swelling after a procedure to break up stones, a tumor pressing on the ureter, scar tissue from surgery or radiation, or a structural problem present from birth. Surgeons also place JJ stents as a precaution after urinary tract surgery to keep the ureter open while tissues heal.
What Happens During Placement
The procedure is done under anesthesia, usually general or spinal. A thin camera called a cystoscope is passed through the urethra into the bladder. The surgeon locates the opening of the affected ureter, threads a thin guidewire up through the ureter into the kidney, and slides the stent over the wire into position. Once the stent is in place, the wire is pulled back, which releases the upper J-curl inside the kidney. Then the scope is withdrawn carefully, allowing the lower J-curl to coil inside the bladder.
The entire procedure typically takes 15 to 30 minutes. Imaging, either X-ray or ultrasound, confirms the stent is sitting correctly before the procedure ends.
How Long It Stays In
Duration depends on why the stent was placed. After a straightforward stone procedure, stents often stay in for about 5 to 14 days. Research from a large study of over 4,400 procedures found that removing a stent too early, at four days or fewer, increased the chance of an emergency room visit, so a minimum of five days is generally recommended for patients who haven’t had a stent before.
For more complex situations like ongoing obstruction from a tumor or healing after reconstructive surgery, a stent may remain for several weeks or even months. Leaving a stent in too long, however, creates its own risks. Encrustation, where minerals from urine build up on the stent’s surface, becomes increasingly likely the longer it stays. Studies show encrustation rates climb from about 9% when the stent is in for less than six weeks, to nearly 48% between six and twelve weeks, and up to 76% beyond twelve weeks.
What It Feels Like to Live With
Most people notice the stent. The symptoms are well documented and quite common. Roughly 50 to 60% of patients experience frequent urination and urgency, that sudden, hard-to-ignore need to go. About 40% report a burning sensation during urination. A feeling of incomplete bladder emptying is even more common, affecting around 76% of patients. Flank pain (a dull ache in the side or lower back) occurs in 19 to 32% of cases, and suprapubic discomfort, a pressure or ache just above the pubic bone, affects about 30%.
Blood in the urine is visible in roughly 25% of patients and can look alarming but is usually harmless. It often results from the stent rubbing against the lining of the ureter or bladder. Physical activity, especially bouncing or jarring movements, tends to make hematuria and discomfort worse. The urgency and frequency are caused by the lower curl of the stent sitting inside the bladder, which irritates the bladder wall and can trigger spasms.
Activity and Recovery
Most people return to school or work within a day or two of having a stent placed. Strenuous activity should be avoided for at least a few days, including lifting anything heavier than about 10 pounds (roughly a gallon of water). Sexual intercourse is best avoided for at least a week. If your job involves heavy lifting or intense physical work, you may need additional time off. Within about a week, most patients are back to their normal daily routines, though stent-related symptoms like urgency and mild discomfort may persist until the stent is removed.
Drinking plenty of water helps. Staying well-hydrated dilutes the urine, which reduces irritation and lowers the risk of mineral buildup on the stent.
How It Gets Removed
The most common removal method uses a cystoscope. A thin camera is passed into the bladder through the urethra, the surgeon grasps the lower curl of the stent with small forceps, and pulls it out. This is a quick procedure, often done in an office setting with local numbing gel, though some patients receive sedation.
Some stents are placed with a retrieval string, a thin thread attached to the lower end of the stent that hangs outside the body through the urethra. When it’s time, a doctor (or sometimes the patient, with instructions) simply pulls the string to slide the stent out, no scope needed. Stents with strings tend to be removed sooner, at a median of about 5 days compared to 9 days for stents without strings. The trade-off is that the dangling string can cause urethral discomfort, may interfere with sexual activity, and carries a small risk of the stent being accidentally dislodged early.
Potential Complications
Short-term side effects like urgency, frequency, and blood in the urine are extremely common and expected. True complications are less frequent but worth knowing about.
- Infection: Urinary tract infections are the most common complication, reported in over 60% of cases in one long-term review. In rare instances, infection can progress to sepsis.
- Migration: The stent can shift out of its intended position, moving up toward the kidney or down into the bladder. One five-year study found migration in about 26% of patients whose stents remained in place for an average of nine months.
- Encrustation: Mineral deposits coat the stent over time, potentially making removal more difficult and increasing the risk of blockage. This is strongly linked to how long the stent stays in.
- Stone formation: In a small percentage of cases, crystals on the stent grow large enough to form new stones.
The risk of these complications rises sharply with longer indwelling times, which is why timely removal matters. Patients with a history of kidney stones, urinary infections, or chronic kidney disease face higher encrustation risk and may need closer follow-up while the stent is in place.