In general, most back muscle spasms occur because of the following reasons:
(1) The muscles are trying to protect themselves from muscle strain
A back spasm can occur after any type of strain or injury to the soft tissues (muscles, tendons or ligaments) in the spine. This type of soft tissue injury typically heals enough within a week or two for the muscle spasms to stop.
(2) The muscles can spasm in response to an underlying anatomical problem
If your back spasm does not get better in 1 to 2 weeks, or it comes and goes overtime in the same area of your back, you may have an underlying anatomical problem in your spine. Some examples of underlying issues that could cause your back to spasm include:
- Facet joint osteoarthritis
- Spinal stenosis
- Degenerative disc disease
- Herniated disc
When these or other underlying anatomical problems are present in the spine, muscle spasms are likely to keep recurring due to ongoing inflammation or instability. It is important to seek medical attention to treat the underlying cause of your symptoms, rather than just treating the symptoms. https://www.nhs.uk/conditions/back-pain/