Kidney stones are a common and often painful medical condition affecting millions worldwide. While many stones pass naturally, some require medical intervention, including surgery. Understanding when surgery is necessary—especially based on the size of the stone—can help you make informed decisions about your health.

What Are Kidney Stones?

Kidney stones are hard deposits of minerals and salts that form inside your kidneys. They can vary in size, shape, and composition. 

The most common types include:

• Calcium oxalate stones.
• Calcium phosphate stones.
• Uric acid stones
• Struvite stones (often linked to infections)
• Cystine stones (rare and genetic)

How Does Kidney Stone Size Affect Treatment?

The size of a kidney stone is one of the most important factors in determining whether it will pass naturally or require surgery. Here’s how size influences treatment options:

When Does a Kidney Stone Require Surgery?

Surgery is generally recommended in the following situations:

• Stone Size Above 6 mm: Stones larger than 6 mm rarely pass on their own and often require medical intervention or surgery.
• Very Large Stones (Above 10 mm / 1 cm): Stones over 10 mm almost always require surgical removal, as the chance of passing naturally is extremely low.
• Severe Pain Not Controlled by Medication: Persistent, severe pain that does not improve with painkillers is a strong indication for surgery.
• Urinary Tract Obstruction: If the stone blocks the flow of urine, causing swelling (hydronephrosis) or risk of kidney damage, surgery is necessary.
• Recurrent Infections: Stones causing repeated urinary tract infections must be removed to prevent further complications.
• Decline in Kidney Function: Any sign of kidney damage or decreased function due to obstruction requires prompt surgical intervention.

Types of Kidney Stone Surgery

Several surgical options are available, depending on the size and location of the stone:

* Laser Lithotripsy (LLT):

Best for stones smaller than 2 cm in the kidney or less than 1 cm in the ureter.

Uses shock waves to break stones into smaller pieces for easier passage.

* Retrograde Intrarenal Surgery (RIRS):

Retrograde Intrarenal Surgery (RIRS) is a minimally invasive procedure used to treat kidney stones. Best for stones smaller than 6mm. 

It involves inserting a thin, flexible tube called a ureteroscope through the urethra and up into the kidney to visualize and break down or remove stones.

* Ureteroscopy (URS):

Suitable for stones located in the ureter or kidney.

Involves inserting a thin scope through the urethra to break up or remove stones.

* Percutaneous Nephrolithotomy (PCNL):

Preferred for stones larger than 2 cm or complex, branched stones (staghorn calculi).

Involves a small incision in the back to directly access and remove the stone.

* Open Surgery:

Rarely performed today, reserved for cases where other methods fail or for very large/multiple stones.

What to Expect After Surgery

• Recovery: Most surgeries are minimally invasive, and hospital stays are typically short (1-2 days for PCNL).
• Risks: As with any procedure, there are risks such as infection, bleeding, or injury to surrounding organs, but these are uncommon.
• Recurrence: Kidney stones can return, so ongoing preventive measures and follow-up are important.

When Surgery Is Definitely Needed (Regardless of Size)

Even smaller stones may require surgery if:

• The stone causes severe pain that can’t be managed.
• There’s an infection or fever, which can become dangerous.
• There’s blockage in the kidney or ureter, risking kidney damage.
• The stone hasn’t moved or passed after several weeks.
• There’s only one functioning kidney, or a kidney transplant.

Prevention Tips

Even if you’ve had kidney stones before, you can reduce your risk of recurrence by:

• Drinking plenty of water (at least 2.5 liters daily)
• Reducing salt and oxalate-rich foods (like spinach, nuts, chocolate)
• Maintaining a balanced diet with adequate calcium and fiber
• Avoiding sugary drinks and processed foods

End note.

Kidney stones can be painful, but the good news is they are treatable. While small stones may pass on their own, stones larger than 10 mm usually need surgical intervention. If you or a loved one are suffering from kidney stones, don’t delay care.

Choose MASSH Hospital for expert diagnosis, minimally invasive treatments, and compassionate care tailored to your needs.

Kidney Stone Patients FAQs.

1. What size of kidney stone typically requires surgery?
Kidney stones larger than 6 mm often need surgical intervention, as they are unlikely to pass on their own. Stones over 10 mm almost always require surgery due to a very low chance of natural passage.

2. Can a 5 mm kidney stone pass naturally?
Yes, a 5 mm stone has about a 50–60% chance of passing naturally with increased hydration and medications. However, if it causes persistent pain or blockage, medical procedures may be needed.

3. How long should I wait before considering surgery for a kidney stone?
If a kidney stone doesn’t pass within 4–6 weeks, causes severe pain, or leads to complications like infections or blockage, surgery is usually recommended.

4. What surgical options are available for large kidney stones?
Common surgical treatments include:

• Laser Lithotripsy for stones under 2 cm
• URS (Ureteroscopy) for stones in the ureter or kidney
• PCNL (Percutaneous Nephrolithotomy) for stones larger than 2 cm or complex shapes

5. Is open surgery still used to treat kidney stones?
Open surgery is rare today and reserved only for cases where other minimally invasive methods fail or the stones are exceptionally large or complex.

6. What are the risks of delaying surgery for a kidney stone?
Delaying necessary surgery can lead to urinary obstruction, recurrent infections, kidney damage, or even permanent loss of kidney function.

7. Can small kidney stones still need surgery?
Yes. Even small stones may need surgical removal if they cause severe pain, infections, blockage, or don’t pass after several weeks especially in patients with only one functioning kidney.

8. How soon can I return to normal activities after kidney stone surgery?
Most patients recover quickly from minimally invasive surgeries like URS or ESWL, often resuming normal activities within a few days to a week. PCNL may require a longer recovery (1–2 weeks).

9. Will I get kidney stones again after surgery?
There is a risk of recurrence, but you can reduce it by drinking plenty of water, limiting salt and oxalates, and following your doctor’s dietary recommendations.

10. Why should I choose MASSH Hospital for kidney stone treatment?
MASSH Hospital offers expert diagnostics, advanced minimally invasive procedures, and personalized care from experienced specialists ensuring safe and effective treatment tailored to your needs.