The sacroiliac joint is responsible for a meaningful portion of chronic low back pain that gets labeled as something else. When the diagnosis is correct, the treatment is specific.

The patient describes pain she's been told is from her lumbar spine. It's in the lower back, slightly to one side, sometimes radiating into the buttock — but typically not past the knee. She's had multiple MRIs showing "age-related disc changes." She's been treated for lumbar disc issues without resolution. The pain is worse when she sits for long periods, when she stands up from sitting, and when she climbs stairs.

This presentation is classic for sacroiliac (SI) joint dysfunction — a condition responsible for an estimated 15% to 25% of chronic low back pain. And a condition routinely missed in favor of lumbar spine diagnoses that happen to show up on imaging.

What the SI joint actually does

The sacroiliac joints connect the base of the spine (sacrum) to the pelvis (ilium) on each side. These joints transmit massive forces between the spine and the legs during every step. They're stabilized primarily by ligaments rather than muscles.

When the SI joint develops dysfunction, it produces pain in characteristic locations: the lower back, the posterior superior iliac spine region, the buttock, and sometimes referral down the posterior thigh.

Why the diagnosis is missed

Imaging doesn't show it well. Standard MRI often doesn't include dedicated SI joint imaging. Degenerative changes in the lumbar spine are extremely common in adults over 40 and easy to blame for symptoms.

Pain distribution overlaps with other conditions. SI pain patterns can mimic lumbar radiculopathy, hip pathology, or facet joint syndrome.

Standard back exam often doesn't assess it. Many clinicians don't include the specific provocation tests that identify SI dysfunction.

Treatment that doesn't address it fails. Patients with SI dysfunction treated for lumbar disc issues typically remain symptomatic.

The clinical signs

  • Pain primarily on one side
  • Pain localized below the belt line and lateral to the midline
  • Pain worse with sitting (especially on a hard surface)
  • Pain with rising from sitting
  • Pain with stair climbing
  • Pain pointing to the posterior superior iliac spine
  • Pain that doesn't change with lumbar flexion or extension
  • Several specific provocation tests (Gaenslen's, FABER, posterior shear, compression, distraction) reproduce the pain

A cluster of positive provocation tests significantly increases the likelihood of SI joint involvement.

What actually resolves it

Chiropractic manipulation of the SI joint has strong supporting evidence. Specific adjustments restore normal motion patterns.

Dry needling of surrounding musculature — gluteal group, piriformis, quadratus lumborum, multifidus.

Specific rehabilitation targeting the deep stabilizers that support SI function.

Shockwave therapy in chronic cases with persistent ligamentous pain patterns.

Addressing contributing factors: leg length discrepancies, pelvic asymmetries, hip mobility deficits, lumbar issues.

Activity modification — avoiding sustained sitting without breaks, modifying sleep position.

When SI pain is beyond conservative care

Most SI dysfunction resolves with conservative care. A subset of cases involve inflammatory conditions, structural instability, or severe refractory pain that may benefit from additional intervention (SI joint injection, radiofrequency ablation, SI joint fusion in rare cases).

Frequently Asked Questions

Is SI joint dysfunction the same as sciatica?
No, though they can coexist. Sciatica involves irritation of the sciatic nerve or its contributing nerve roots. SI dysfunction produces pain in characteristic patterns but typically doesn't produce neurological symptoms.
Can pregnancy cause SI dysfunction?
Yes. Hormonal changes during pregnancy increase ligamentous laxity, and the changing biomechanics place significant demand on the SI joints.
Does an MRI show SI dysfunction?
Not reliably. Clinical examination is more important for diagnosis than imaging in most cases.
How many treatments does it typically take?
Many patients notice meaningful improvement within 4 to 6 visits. Chronic cases may require 10 to 15 visits over 2 to 4 months.

If chronic low back pain has been treated as a lumbar disc issue without resolution, schedule a consultation at Stryde Health and Performance in Boynton Beach. SI joint dysfunction is one of the diagnoses we identify most often in patients who have failed treatment for other back pain diagnoses.