Lateral thigh tendon pain may be caused by the following reasons: First, it may produce strain here. For example, if the patient has strained the muscles and tendons of the lateral thigh in the course of strenuous activities, then the tendon pain here may occur; second, it may be caused by the spasm of the iliotibial bundle. This type of disease is often seen when the patient sits or stands for a long time, or curls up somewhere for a long time. This can lead to spasm and contracture of the lateral iliotibial bundle over time. Such patients tend to feel a great deal of pain in the tendons on the side of the thigh during the process of straightening the knee; third, it may be caused by lesions of the peripheral nerves. For example, at the onset of lumbar disc herniation, it may cause radiating pain here, and make the patient mistakenly think that it is tendon pain; Fourth, it may also be caused by long-term cold here. If this part of the long-term cold, then it may cause some muscles, tendons produce spasm, and then lead to pain.