Sciatica is nerve pain that starts in the lower spine and travels down the sciatic nerve into the buttock and leg. It usually happens when a herniated disc, bone spur, or narrowed spinal canal presses on a nerve root. But sciatica is not the only cause of pain in the lower back, hip, and leg. The sacroiliac (SI) joint, where the base of the spine meets the pelvis, can cause pain that feels a lot like sciatica. Many people searching for sciatica relief in 2026 actually have an SI joint problem, and the difference matters because the two are treated very differently.
What does sciatica feel like compared to SI joint pain?
Sciatica tends to feel sharp, electric, or burning, and it follows a line down the back of the leg, often past the knee and sometimes into the foot. Numbness, tingling, or weakness in the leg or foot is common, and coughing, sneezing, or long periods of sitting can make it worse.
SI joint pain is usually characterized by a deep ache low in the back, just above the buttock, and often on one side. It can spread into the hip, groin, or upper thigh, but it rarely goes below the knee and does not usually cause numbness or weakness. People often point to one spot near the dimples of the lower back. It is possible to have both at once, especially after a prior spinal fusion, which is one reason a careful exam matters more than a self-diagnosis.
What triggers a sciatica or SI joint flare-up?
Sciatica flares are tied to pressure on the nerve. Bending forward, lifting, twisting, and long car rides all increase disc pressure.
SI joint flares are tied to load on the joint. Standing on one leg to get dressed, climbing stairs, getting in and out of a car, and rolling over in bed are classic triggers. Pregnancy, arthritis, and a past fall onto the buttock can all make the joint less stable and more prone to flare-ups.
Quick clues that help sort out the source of your pain:
- Pain that shoots below the knee with tingling or weakness points toward sciatica.
- Pain that stays above the knee and is worse when you stand on one leg or climb stairs points toward the SI joint.
- Pain that started after a fall, pregnancy, or a spinal fusion raises the odds of an SI joint problem.
How is the right diagnosis made?
Imaging alone often cannot provide a diagnosis. An MRI may show a bulging disc that is not the true source of your pain, while the SI joint can look normal on a scan and still be the problem. That is why our providers start with your story and a hands-on exam. Movement tests that stress the SI joint, along with checks of reflexes, strength, and sensation in the legs, help point to nerve or joint involvement.
When the exam and imaging do not agree, a diagnostic injection can settle it. Numbing medicine placed into the SI joint under image guidance should give short-term relief if the joint is the pain source. A selective nerve root block does the same for a specific spinal nerve.
Why the diagnosis changes the treatment plan
Sciatica from a herniated disc is usually managed first with activity changes, physical therapy aimed at taking pressure off the nerve, and anti-inflammatory medication. If leg pain does not settle, an epidural steroid injection can calm the inflamed nerve root. When weakness is progressing or pain stays severe, a minimally invasive microdiscectomy removes the piece of disc pressing on the nerve.
SI joint pain calls for a different plan. Physical therapy builds hip and core strength to stabilize the joint. SI joint injections can relieve pain for weeks to months, and radiofrequency ablation can quiet the small nerves that carry pain from the joint for longer. For pain that keeps returning, minimally invasive SI joint fusion stabilizes the joint with small implants inserted through a short incision.
Our approach is to find the source of the pain first, since surgery is usually the last option. Because our neurosurgeons, orthopedic surgeons, and interventional pain specialists work together in one practice, patients get a clear answer without bouncing between offices.
Getting a clear answer for your back and leg pain
If lower back pain has been traveling into your hip or leg for more than a few weeks, it is time to find out exactly where it is coming from. Schedule an appointment at Florida Surgery Consultants at any of our locations in Tampa, Largo, Lakewood Ranch, Lakeland, Brooksville, Ocala, or Gainesville, and our team will build a plan around the real source of your pain.
