The pain of the thighs may be related to the following causes: 1, there may be a strain of the muscles and tendons around the thighs, which is often seen when patients do a certain action beyond their limits, or do strenuous activities without warming up, which may lead to strain of the muscles and tendons around the thighs, and then cause pain. 2, there may be muscle strain, such as patients do long-term high-intensity exercise or labor, which may cause pain when exerting force. The patient may have a strain on the muscles and tendons around the thighs, which may cause pain when exerting force, and sometimes excessive exercise may cause rhabdomyolysis. 3, there may be peripheral nerve lesions, for example, in severe lumbar disc herniation or sciatica attack, the patient will often show the radiating pain in the lower back and lower limbs, and have curled up the lower limbs, reluctant to move. In this case, if the patient can barely move the lower limbs, he or she may have to do so. At this time, if the lower limbs are forced to move, it is possible that in the process of thigh force, the nerve will be stimulated by pulling, which will lead to radiating pain in the lower limbs, and then the patient will mistakenly think that it is the tendon pain in the back of the lower limbs.