Sudden soreness in the thighs with difficulty in walking is commonly caused by long-term muscle strain, lumbar disc herniation or acute attack of lumbar spinal stenosis, as follows: First, long-term muscle strain: it can lead to sudden aggravation of the lesion, and the patient will show sudden lower limb soreness, difficulty in walking, and accompanied by symptoms of limb weakness. At this time, through massage, hot compress and acupuncture treatment, the symptoms will be significantly relieved. Second, acute attack of lumbar disc herniation or lumbar spinal stenosis: the above diseases can also lead to sudden soreness and pain in the thighs, accompanied by walking difficulties, and in severe cases, intermittent claudication can also occur, the patient’s lower extremity radiated pain symptoms will gradually increase, especially can affect the patient’s movement and work, through nuclear magnetic or CT scan examination can be found lesion site and lesion degree. In the early stage, medication and physical therapy can be used to relieve the clinical symptoms. Patients should pay attention to the protection of thigh muscles and lumbar spine to avoid strain and trauma.