Tennis elbow belongs to the category of elbow labor in traditional Chinese medicine, and Elongation Tendon Capsule does not have the effect of treating tennis elbow. Extension Tendon Dan Capsule has the effect of relaxing tendons and collaterals, activating blood circulation to eliminate blood stasis, and reducing swelling and pain (eliminating swelling and pain). It is composed of Dilong, Strychnine, Saffron, Boswellia, Fenghui, etc. It is used to relieve blood stasis, remove blood stasis, and reduce swelling and pain. It is used for sequelae of bone fracture caused by blood stasis and collateral obstruction, cervical spondylosis, hypertrophic spondylitis, chronic arthritis, sciatica, and frozen shoulder. It should be noted that pregnant women and lactating women are prohibited, cardiac patients should be cautious; should not be overdosed, prolonged use. If there is a need for medication, it should be used under the guidance of a Chinese medicine practitioner, and should not be used blindly on its own to avoid adverse consequences.