Hip pain when walking on the left leg may be caused by cauda equina syndrome, sciatica, hip synovitis and other diseases, which need to be treated with medication, surgery and other treatments according to the cause. 1. Cauda equina syndrome: common symptoms include hip pain, lower limb motor and sensory disorders. Patients need to follow the doctor’s instructions to apply vitamin B1, vitamin B12 and other nutritive drugs, as well as methylprednisolone, dexamethasone and other glucocorticoids. If there is localized edema, it is necessary to follow the doctor’s instructions to apply mannitol, hepatic saponin and other dehydrating agents. If conservative treatment is not effective, surgical treatment such as cauda equina release and cauda equina anastomosis should be adopted. 2. Sciatica: Typical symptoms are pain in the buttocks and the back of the thighs, which can be triggered by factors such as lower limb activities. Patients need to follow the doctor’s instructions to apply ibuprofen, aspirin and other non-steroidal anti-inflammatory drugs, as well as tretinoin, prednisone and other glucocorticosteroids. Some patients need to cooperate with the doctor to apply anesthetics such as lidocaine and procaine for closure therapy, as well as muscle relaxing drugs such as etoperisone and cyclobenzaprine. If non-surgical treatment is ineffective, surgical treatment such as minimally invasive discectomy and laminectomy should be considered. Physical therapy such as ultrashort wave and infrared irradiation can be used in the acute stage. 3. Hip synovitis: the main symptoms are hip pain, swelling, limited activities, which can be manifested as pain in the hip when walking on the left leg. Patients need to follow the doctor’s instructions to apply etoricoxib, celecoxib and other non-steroidal anti-inflammatory drugs, if the infected synovitis, you need to follow the doctor’s instructions to apply ceftriaxone, cefuroxime and other antibiotic drugs. Some patients need to cooperate with the doctor in the local injection of sodium vitrate. Physical therapy such as ion implantation and ultrasound can also be taken. If non-surgical treatment is ineffective, surgical treatment such as synovectomy and artificial hip replacement is needed. Patients whose hips hurt when they walk on their left leg need to go to the hospital in time and cooperate with the doctor to actively treat the primary disease. The use of drugs must follow the doctor’s instructions.