Tendon sheath inflammation is a sterile inflammation caused by overwork and frequent flexing and extending of the tendon, leading to repeated abrasion and compression within the fibrous sheath of the tendon sheath. This results in local exudation, swelling, and fibrosis, which narrows the sheath canal. If the symptoms are mild, conservative treatment can be chosen, such as applying non-steroidal anti-inflammatory and analgesic medications, and topical anti-inflammatory and analgesic plasters for symptomatic treatment, combined with rest, immobilization, and physical therapy to alleviate symptoms. If symptoms worsen, local encapsulation treatment may be necessary. If symptoms persist and conservative treatment is ineffective, then surgery may be required.