With the lower back taking much of the body's weight, it's not unusual to sustain a strain or other injury of the sacroiliac (SI) joint by stepping off a curb wrong, overstriding on a downhill or taking a tumble on your buttocks. The resulting inflammation can cause misalignment or mild rotation of the affected side of the pelvis and a difference in leg length, setting the stage for additional injury. When your SI joint feels inflamed, ramp down your training and contact your health care professional for an evaluation to avoid sacral stress fractures and other conditions that could derail your run for months.
About Your SI Joint
The sacroiliac joint is where your sacrum — the bony section across your lower back — joins with the ilium, or hipbone. Although there's little movement in these joints, the ligaments and muscles connected to the ilia can easily become inflamed, causing pain. Typically, the pain results after the SI joints become either too stiff or too loose.
In women, hormonal changes such as those experienced during pregnancy and the menstrual period can cause the SI joint to become more flexible than normal. Stiffness in the SI joint from straining the lower back, overtraining or sitting too long in one position — such as during an extended car ride — can also initiate inflammation.
When one sacroiliac joint becomes inflamed, the two sacra and ilia no longer work together as a single unit. The resulting pelvic imbalance will exacerbate the inflammation when doing ordinary activities such as bending over, walking or running.
Is It SI Inflammation?
Although your SI joint is located in that little indentation on either side of your lower back, that may or may not be where you feel pain when it's inflamed. It's most common to feel it on one side of the lower back, but the sensation could also seem to be coming from one side of the tailbone or groin. The symptoms in the joint area may range from numbness to a dull ache or even a stabbing pain.
Or, you could experience SI inflammation as a sensation in a different part of your body entirely. Tingling or pain running down the affected leg is quite common. You might even feel like you have a tight or pulled glute muscle.
You might not notice sacrum pain when running. It's not unusual for it to become apparent after sitting at your desk for several hours, getting up or bending over to pick up something. Pain experienced while walking, running or standing is often relieved when you sit or lie down.
Don't Power Through
"No pain, no gain" is a losing game when it comes to SI inflammation and running. Because the injury can cause pelvic imbalance, rotation and unevenness of leg length, it's better for your body if you treat the inflammation rather than push through additional workouts and risk worse injury from compromised pelvic balance.
The first rule of SI inflammation and running is to rest, according to Good Shepherd Rehabilitation Network/Penn Medicine. That's easier said than done when you're dedicated to a fitness routine or training for a running event. However, it's the best thing you can do for your body since running puts continued stress on the inflamed SI joint.
Call Your Doc
It's crucial to get your SI joint evaluated if you're experiencing pain, so make an appointment with your health care professional. This is best done while you're already taking time off from your running routine for rest.
Your doctor will physically examine the area and put you through some mobility tests to determine the extent and location of the pain. Expect to get X-rays and an MRI of the area. This helps your doctor determine the seriousness of your injury and ascertain whether you have a sacral stress fracture, chronic SI dysfunction or other condition that needs specific treatment beyond basic rest and recuperation.
Before heading to the doctor, take some time to think about the nature of your injury and jot down a few notes. Your medical professional is likely to ask:
- When did the pain start?
- What were you doing when you first noticed it?
- Did you have a fall or other injury that might have caused the problem?
- Have you experienced similar symptoms in the past?
- Where, specifically, is the pain located? Is it localized? Or does it radiate down your leg or up your back?
- On a scale of 1 to 10, how much pain do you normally experience?
- Do certain activities make it worse?
- When is the pain at its most intense? (running, bending, sitting, etc.)
- Have you recently given birth? Are you pregnant? When was your last menstrual period and did it coincide with your symptoms in any way?
Getting Physical Again
Although your doctor is unlikely to clear you to run on down the road immediately if you're experiencing SI joint pain, he is likely to prescribe physical therapy to optimize healing and mobility. Your therapist will assess the extent of your injury by examining your spine's position; assessing strength in hip, pelvic and lower extremity muscles; and evaluating your mobility.
Once evaluated, your physical therapist will help you get back in your sneakers and running again through a regimen of targeted exercises designed to correct body mechanics through improved movement patterns. Besides directly targeting the SI joint, exercises will help strengthen the pelvic floor, butt muscles and lower abs to provide greater stabilization for the joint in the future. Expect to take home targeted stretching exercises that will help you gain more flexibility and take stress off the SI joint.
Other modalities you might experience in physical therapy include heat or cold packs, electrical stimulation of the area or soft-tissue massage to help realignment of the pelvis. Your therapist might also prescribe a brace to support your sacrum and SI joint as you recover, especially once you're cleared to start running again.