After the small arm injury to the tendon to stop activities and labor, and then ice packs, observe the small arm local pain, swelling and finger movement. If there is no obvious pain and limited finger movement, no localized swelling, suggesting a mild strain, through rest and braking for about 2 weeks to basically heal. If there is significant swelling and pain in the lower arm, limitation of finger movement, and pain in the lower arm worsens with movement, this suggests that there may be a partial muscle or tendon strain, and strict braking with a cast or brace is required for 3 weeks. If there is obvious pain, swelling and lumps in the lower arm, and if there is a decrease in strength and pain after moving the fingers, it suggests that there may be a complete muscle rupture, and then further treatment is needed in the hospital to avoid delaying the disease.