Buttock pain and ankylosing spondylitis

The sacroiliac joints sit between the lower spine and pelvis. Inflammation there may produce an ache in one buttock or alternate between sides. Pain linked to ankylosing spondylitis may feel worse after rest, disturb sleep, and ease as the body gets moving. Stiffness in the lower back or hips can accompany it.

Buttock pain also has other possible causes, including muscle strain, irritation around the hip, or a nerve problem. Its location alone cannot confirm ankylosing spondylitis. A clinician considers the pattern, examination findings, other symptoms, and any appropriate blood tests or imaging.

Keep a brief record of which side hurts, whether the pain wakes you, how it changes with movement, and whether stiffness follows rest. Gentle, regular movement may reduce stiffness; a physiotherapist can tailor mobility, posture, strengthening, and pacing to your current ability. Avoid forcing a painful stretch or abruptly increasing exercise during a flare.

If you already have a treatment plan, take medicines as prescribed and discuss persistent breakthrough symptoms with the prescribing clinician. Do not start, stop, or increase anti-inflammatory medicine without checking whether it is suitable for you, especially if you have stomach, kidney, heart, bleeding, or medication concerns.

Arrange a medical assessment if buttock pain persists, repeatedly returns, limits walking or sleep, or occurs with ongoing back stiffness. Seek urgent care for new leg weakness, numbness around the groin or buttocks, loss of bladder or bowel control, severe pain after an injury, fever with feeling very unwell, or a hot and swollen joint.

Ask whether the pattern suggests sacroiliac inflammation, whether examination or imaging would change the plan, which movements are appropriate during a flare, and how to tell inflammatory pain from a hip, muscle, or nerve problem. If treatment is already underway, ask what symptom changes would justify adjusting it.