There are many causes of left hand joint pain in daily life, including trauma, tenosynovitis, arthritis, tumors, metabolic bone disease, etc. The pain performance and accompanying symptoms caused by different causes are different, and the treatment may also be different. 1. Trauma: Trauma is a common cause of left hand joint pain. The hand is located at the end of the upper limb, can complete many fine movements, after being stimulated by external forces, it is easy to cause fractures or soft tissue damage, resulting in painful symptoms, usually accompanied by local swelling, need to be combined with X-rays, CT, MRI clear diagnosis, the need for braking, with oral anti-swelling painkillers, if the fracture may require external fixation or even surgery; 2, tendovaginitis: tendovaginitis is The tendon sheath of the flexor tendon of the left finger becomes aseptic and inflammatory under the influence of strain and other factors, resulting in an increase in the binding effect on the tendon, causing the finger to pop and ring, accompanied by joint pain, which can be treated with pain relief medication and, if necessary, with small acupuncture; 3, arthritis: for example, rheumatoid arthritis, osteoarthritis, gouty arthritis, etc. The small joints of the fingers can be invaded, generally both hands can appear, but the left hand may be the first, in addition to joint pain will also be accompanied by morning stiffness, redness, swelling, limited activity, etc., need to be clearly diagnosed through imaging, laboratory tests, and then the corresponding drug therapy or even surgery; 4, tumors: such as osteosarcoma, synovial sarcoma, etc., the need for surgical treatment supplemented by radiotherapy; 5, metabolic bone disease: caused by Vitamin D metabolism disorders caused by osteochondrosis, such as insufficient phosphorus intake, vitamin D deficiency, etc., need to supplement the corresponding elements for improvement.