The following causes are common in women with hidden pain at the root of the left thigh: first, excessive strain on the hip joint: if the unilateral lower extremity continues to carry excessive weight, the body’s center of gravity shifts to the left lower extremity, which can cause excessive strain on the left side of the joint, resulting in hidden pain in the left hip joint, usually accompanied by joint pain and weakness, the patient cannot stand or walk for a long time, and needs rest to make it ease. Second, left hip osteoarthritis: usually seen in elderly female patients, prolonged excessive wear and tear can cause damage to the articular cartilage, patients in the early and middle stages of the disease, will show symptoms of hidden pain at the root of the left thigh, and at the same time will be accompanied by limited hip joint activities. After timely treatment, patients can get significant relief of clinical symptoms. Patients should strengthen the strength training of the muscles around the hip joint to prevent the occurrence of symptoms.