Back pain of varying intensity and duration may arise from injury either to the bone itself, as occurs in fractures, or to muscles, tendons, ligaments or nerves.
Muscle tears may result from direct trauma or from overuse, as when participating in sports, or from prolonged awkward postures and poor body mechanics.
When a muscle is strained or pulled muscle or torn, its blood vessels are also damaged and surrounding tissues become inflamed.
Muscles strains and tears often produce spasm, a sudden, intense, involuntary muscle contraction.
Although such spasms can be painful, it is the body's natural mechanism for protecting injured tissue by temporarily splinting the part to limit movement for healing purposes.
Like muscles, ligaments supporting the joints of the back are also subject to injury.
They can be overstretched or torn, from a fall for example, or from overuse as in activities such as ballet dancing or gymnastics.
The spine's fibrous ligaments can also be damaged from the cumulative stress of habitual bas posture and poor body mechanics.
The type of damage known as a sprain often affects the ligaments that bind together the spine's facet joints.
This most often occurs in the lumbar area, although the sacroiliac joints are also vulnerable, particularly during a fall or a twisting action.
Precautions to take to prevent such injury include proper warming up and stretching exercises before engaging in sports or other strenuous activities, and training and practice in correct lifting technique, where applicable.
Cumulative stress can be averted by attention to good postural habits and by taking frequent breaks from repetitive work to do appropriate tension relieving exercises.