What it is
Sacroiliac joint dysfunction refers to pain believed to arise from the SI joints or surrounding ligaments and muscles. It presents as buttock or low-back pain often worse with single-leg loading, stairs, or prolonged standing.
True instability is rare. Most cases reflect irritated tissues and altered load sharing that respond to rehabilitation.
What happens when it occurs
Altered force closure and muscle coordination increase stress across the SI region. Restoring hip and trunk strength and movement efficiency reduces symptoms.
Common causes and risk factors
- Pregnancy and postpartum changes
- Hypermobility and rapid training increases
- Prolonged standing or heavy lifting at work
- Prior lumbar or hip problems
Who is most affected
Active adults, postpartum individuals, and workers in standing or lifting roles.
Typical symptoms
- Achy pain near the dimples of the lower back, sometimes radiating to the thigh
- Pain with stairs, single-leg stance, or rolling in bed
- Morning stiffness that eases with movement
When to seek care
Seek care if symptoms persist beyond two weeks, disturb sleep, or limit walking and stairs.
How we diagnose
History and clusters of provocation tests alongside assessment of hip strength and movement. Imaging is used to exclude other causes when indicated.
Management
- Education and pacing, avoiding long static postures
- Hip abductor and extensor strengthening, trunk endurance
- Gait and lifting technique coaching
- Pelvic belt during high-load tasks if helpful
Rehabilitation milestones
Phase 1 weeks 0 to 2: pain control, isometrics, short walks, belt trial.
Phase 2 weeks 2 to 6: heavy slow strength, step-down control, loaded carries.
Phase 3 weeks 6 to 12: hills, stairs, change-of-direction drills.
Phase 4 weeks 12 to 16: full work and sport loads.
Readiness to progress
- Pain-free single-leg stance and step-downs
- Hip strength within 90 percent
- No next-day flare after hills and stairs
Prevention
- Keep baseline strength and endurance
- Break up long standing or sitting
- Progress return-to-running and lifting in steps
Australia snapshot
- Regular presentation in primary care and women’s health pathways
- Common in people who stand at work and in runners during load spikes
- Access to pelvic belts and targeted physiotherapy is widespread
Latest insights
Muscle coordination and strength restore force closure. Belts assist during the transition.
Progress is best tracked by next-day comfort and single-leg task performance.


