• Nerve irritation (meralgia paresthetica), more likely if there is burning, tingling, numbness, or altered sensation over the outer thigh.
• Pain referred from the lower back or sacroiliac region, especially if there is back pain or pain travelling below the knee.
• Less often, a hip-joint or gluteal tendon problem that needs examination.

What to do now

• Avoid sitting continuously. Stand and walk gently for 2-3 minutes every 30-45 minutes.
• Sit with both feet supported, knees roughly hip-width apart, and avoid crossing your legs for prolonged periods.
• Avoid low, soft chairs and deep sofas. Use a firmer, higher chair if possible.
• Do not stand with your weight pushed onto one hip.
• If lying on the painful side worsens it, lie on the other side with a thick pillow between the knees, or on your back with a pillow below the knees.
• Keep active, but temporarily reduce aggravating activities such as long walks on slopes, running, repeated stairs, or deep squats if they provoke pain.
• Gentle gluteal strengthening is usually useful, but do not force painful stretches or exercises. A physiotherapist can assess hip strength, back movement, posture, and teach suitable exercises.
• Heat or a wrapped cold pack for 15-20 minutes may help. Do not apply directly to skin.
• If you can safely take them, simple pain relievers such as paracetamol may help. Check with a clinician or pharmacist before anti-inflammatory medicines if you have kidney disease, stomach ulcer/bleeding history, take blood thinners, are pregnant, or have significant heart disease.

Arrange a clinical assessment

Seek urgent care sooner if you have

• New leg weakness, foot drop, loss of bladder or bowel control, or numbness around the groin
• Fever, redness, warmth, marked swelling, or feeling unwell
• Inability to bear weight, severe pain after a fall/injury
• Unexplained weight loss, constant night pain, or a history of cancer
• A swollen, painful calf or sudden shortness of breath

How to tell the patterns apart

• Pain starts in the low back or buttock and travels down the back or side of one leg, sometimes below the knee to the foot.
• Burning, electric, shooting pain, tingling, numbness, or weakness.
• Worse with coughing, sneezing, bending, or prolonged sitting.
• True sciatica most often affects the buttock and back of the leg, often including the foot or toes, as described by the NHS sciatica guidance.

• Pain mainly just to one side of the low back, near the “dimple” area above the buttock.
• Pain in the buttock, groin, or back/side of thigh.
• Worse with prolonged sitting, standing on one leg, turning in bed, getting out of a car, stairs, or walking.
• It may sometimes refer farther down the leg, but usually does not cause marked numbness or weakness. Orthopaedic references note that SI-joint pain can refer to the buttock, groin, posterior thigh, calf, and occasionally foot. Campbell's Operative Orthopaedics, 15th ed.

• Very local tenderness when pressing the bony outer side of the hip.
• Worse lying on that side, climbing stairs, crossing legs, or sitting with the hip compressed.
• No tingling or numbness.

Practical precautions

• Avoid sitting in the same posture for more than 30-45 minutes. Get up, walk briefly, and change position.
• Use a chair with back support. Keep both feet on the floor and avoid prolonged leg crossing.
• Do not stay slouched on a sofa or sit on a wallet/phone in a back pocket.
• Keep gentle walking and normal activity rather than bed rest, but reduce activities that clearly flare the pain.
• Use heat for 15-20 minutes if it eases the back/buttock muscle tightness.
• A physiotherapist can examine the hip, back, SI region, strength, sensation, and reflexes to identify the likely source. Self-tests cannot reliably distinguish these problems.

• Strength when pushing the foot down and standing on tiptoes
• Ankle reflex
• Sensation over the outer foot/little toe
• Whether back movement or a straight-leg-raise reproduces the leg pain

Until assessed

• Avoid long periods of sitting, slumped sitting, and prolonged leg-crossing.
• Change position and walk gently for a few minutes every 20-30 minutes.
• Do not stay in bed or completely stop activity. Use short, frequent walks within tolerable limits.
• Avoid heavy lifting, repeated forward bending/twisting, and forceful hamstring or “nerve” stretches that shoot pain down the leg.
• Heat or cold for 15-20 minutes can be tried, whichever helps.
• For sleep: on your back with a pillow under the knees, or on your side with a pillow between knees, often reduces strain.
• Use pain medicines only if appropriate for you and after advice from a pharmacist/clinician, especially if you have ulcer disease, kidney disease, blood-thinner use, heart disease, or are pregnant.

Get emergency care now if any of these occur

• New or worsening weakness, such as inability to rise on the left toes, foot giving way, or difficulty walking
• Numbness around the genitals, anus, or inner thighs
• New difficulty starting urination, inability to pass urine, urine leakage, or loss of bowel control
• Numbness or weakness affecting both legs
• Fever, recent significant injury, unexplained weight loss, or severe constant night pain