Why we have Back Sprains / Strains
Most people sprain/strain ligaments and muscles of the back. The back is a very complex structure. The main purpose is to support your frame, allowing safe movement, while protecting the important vital organs in your abdominal area. The spine is also the conduit for the nerve signals going from your brain to the legs and organs. The back must be strong, for protection, while also flexible to allow movement. To achieve those purposes, the back is a complex organization of bones, ligaments, muscles and nerves. Each element has very specific functions, and proper function demands precise coordination. Because of so many moving parts, it is actually amazing that we do not have more back pain.
The muscles of the back are multiple and paired, right and left. The Muscles must also be balanced to allow the back to remain erect and coordinated. As we twist from side to side, one set of muscles must contract, and shorten (concentric), while a corresponding set of muscles on the other side of the motion must elongate, in a controlled manner (eccentric). Considering, that there are multiple planes of motion (so called six degrees of motion), the complexity of the coordination of these muscles become more apparent. All muscles fatigue with excessive use. With the fatigue, these muscles can get overstretched, leading to the back muscle Strain.
The structure that becomes like a rope, extending off muscles are called tendons. The tendon is the extention of the muscle that attaches to the bones. In the back, there are multiple small muscles with multiple tendons that insert onto the spine bones (spinous processes). These tendons can also become frayed or weakened during overuse, or overstretch. This stretching of a tendon is also considered a back strain.
In addition to the muscles and tendons, there are ligaments, which are rope like structures that connect a bone to the bone. In the back, there are multiple paired ligaments that connect boney parts to one another. Over time, these ligaments can wear or stretch, causing the so call back Sprain.
As you can imagine, all these paired muscles, tendons, and ligaments can be a source of pain. With all the necessary pairing, and coordination of all these structures, an overstretch incident can be the source of pain. With so many components involved, it would be very difficult to definitely identify which specific muscle, tendon, or ligament is the cause of the pain. In addition, as these are soft tissues, X-rays would not be able to identify the cause. Even with MRI’s, unless there is a significant tear of any of these components, the study will not likely pin point the soft tissue pain generator.
So, when you have back pain, it is likely secondary to a sprain/strain of one of these muscles, tendons or ligaments. While you Physician will also ask questions to make sure it is not something more serious, the vast majority of back pains are from these sprains and strains. Also remember, that as we all age, these components do wear away. It is a part of life. Luckily, most episodes of back sprains /strains do heal with minimal or no pain.
- Ren CZ, Fang XL, Du XZ. [Fifty-six cases of acute lumbar sprain treated by buccal acupuncture combined with exercise therapy]. Zhongguo Zhen Jiu. 2014 Mar;34(3):245-6. PubMed PMID: 24843964