Chronic lumbar muscle strain is a common clinical disease with many factors. The main symptom is lumbar pain, which is aggravated by daytime exertion and can be reduced after rest. The treatment is mainly non-surgical, but if various non-surgical treatments are ineffective, surgical treatment can be performed. What causes the symptoms of lumbar muscle spasm? 1.After acute lumbar sprain and long-term recurrent lumbar muscle strain. 2, long-term repeated excessive lumbar movement and excessive load, such as long periods of sitting, standing or from the bent position to the upright position holding heavy objects, lifting objects, can make the lumbar muscle in a long-term high tension state, over time can lead to chronic lumbar muscle strain. 3, untimely treatment, improper treatment. 4, chronic lumbar muscle strain and climate, environmental conditions also have a certain relationship, the temperature is too low or humidity is too large can promote or aggravate the lumbar muscle strain. Muscle cramps are caused by a decrease in the threshold of nerve or neuromuscular stress, which makes the frequency of nerve action in the muscle suddenly increase, causing muscle tonic contraction. It is seen in chronic lumbar muscle strain, and some occupations require working in a fixed position, which is also an important cause of strain injury. Acute soft tissue sprains may also turn into chronic strains if they fail to obtain full recovery.