Lying down with no symptoms walking or standing pain left hip soreness may be sacral arthritis, it may also be caused by synovitis of the hip joint, left hip strain and so on, it is recommended that the patient go to the hospital for examination, after clarifying the cause of the disease, symptomatic treatment. 1. Sacral osteoarthritis: Sacral osteoarthritis, also known as sacroiliac arthritis, is mainly caused by ligament damage due to abnormal pressure on sacroiliac joint strain. Symptoms may also include morning stiffness, pain, joint instability, and limb dysfunction. 2. Hip synovitis: Hip synovitis is mainly caused by infection or trauma to the hip joint. In addition, the patient may also have limited movement, swelling, soreness and pain in the outer hip, lower back and thighs, and the symptoms will worsen after weight-bearing running and decrease when lying down. 3. Left hip strain: left hip injury or trauma, chronic strain causes may cause. Symptoms of left hip pain when walking or standing. In daily life, patients should reduce the wear and tear on the hip joint, avoid lifting heavy objects, and avoid excessive strenuous exercise for a long time. Patients are advised to seek timely medical examination and targeted treatment.