What causes numbness from the left arm to the fingers?

Generally, numbness in the left arm extending to the fingers may be caused by prolonged compression, improper posture, Raynaud's phenomenon, peripheral neuritis, or shoulder periarthritis. Symptomatic treatment such as general therapy and medication may be needed. If discomfort occurs, it is recommended to seek timely medical advice and undergo corresponding treatments under a doctor's guidance. Detailed analysis is as follows:

1. Prolonged Compression

Prolonged compression can press blood vessels, obstruct blood circulation, and compress nerves, thereby blocking nerve conduction and causing numbness. It is recommended to promote blood circulation and relieve numbness through local massage, hot compresses, and similar methods.

2. Improper Posture

Maintaining the same posture for a long time, such as working at a desk or using computers and mobile phones, can cause upper limb muscle tension and poor blood circulation, leading to numbness, which may be accompanied by symptoms such as neck and shoulder pain. It is recommended to adjust posture, rest appropriately, and avoid maintaining the same posture for extended periods.

3. Raynaud's Phenomenon

Raynaud's phenomenon is a vascular reactive disorder. When exposed to cold or emotional excitement, small peripheral arteries spasm, causing the fingers to turn pale, cyanotic, and numb. When exposed to cold or emotional fluctuations, the finger color changes significantly, first turning white, then purple, and finally returning to a rosy hue. It is recommended to use medications such as nitroglycerin patches, amlodipine tablets, and prazosin hydrochloride tablets under a doctor's guidance.

4. Peripheral Neuritis

Peripheral neuritis refers to inflammation or damage to nerves in the extremities of limbs, which may cause sensory loss or abnormalities, resulting in numbness and pain. It may also be accompanied by muscle weakness and muscle atrophy. It is recommended to use medications such as mecobalamin capsules, acetaminophen tablets, and carbamazepine tablets under a doctor's guidance.

5. Shoulder Periarthritis

Shoulder periarthritis is mainly caused by long-term excessive shoulder activity, poor posture, acute shoulder contusions, and similar factors. In cases of shoulder periarthritis, inflammation of the muscles and tendons around the shoulder joint may involve the brachial plexus nerve, causing upper limb numbness. It is often accompanied by shoulder pain and restricted movement. It is recommended to follow medical advice to use medications such as tramadol hydrochloride sustained-release tablets, nimesulide tablets, and ibuprofen sustained-release capsules to alleviate symptoms.

It is recommended to perform appropriate massage in daily life, gently massaging from the neck to the shoulders, arms, and fingers to promote blood circulation and reduce numbness.