Muscle or Ligament Strain

It can range from a dull, constant ache to a sudden, sharp pain that may shoot down the leg. Sometimes it can come on suddenly from an accident, a fall, or lifting something heavy, or it can develop slowly because of age-related degenerative changes in the spine. In some cases, inflammatory arthritis disorders or other medical conditions cause back pain.

Herniated or Bulging Discs

Discs function as cushions between the bones (vertebrae) in your spine. The soft material inside a disc can bulge or rupture and press on a nerve. However, you can have a bulging or herniated disc without back pain. Disc disease is often found incidentally when you have spine X-rays for some other reason.

Arthritis

Osteoarthritis can affect the lower back. In some cases, arthritis in the spine can lead to a narrowing of the space around the spinal cord, a condition called spinal stenosis.

Skeletal Irregularities

A condition in which your spine curves to the side (scoliosis) also can lead to back pain, but generally not until middle age.

Osteoporosis

Your spine's vertebrae can develop painful fractures if your bones become porous and brittle.

Poor Posture

Prolonged periods of poor posture can put strain on the muscles and ligaments in your back, leading to pain.

Inactivity

A sedentary lifestyle, particularly if combined with poor posture or incorrect lifting techniques, can lead to back pain.

Kidney Disease

Kidney disease can cause back pain, especially if there's a blockage or infection. Kidney pain is often felt in the back, under the ribs, and to either side of the spine. While it is more common to feel kidney pain on only one side, some health problems may affect both kidneys and cause pain on both sides of your back. In such cases it is best to seek your doctor's advice

Injuries

Accidents, falls, or sports injuries can cause back pain. Even minor injuries can lead to chronic back pain if not treated properly.

Medical Conditions

Conditions such as kidney stones, infections, or tumors can also cause back pain.

Psychological Factors

Stress, anxiety, and depression can contribute to back pain, as they can lead to muscle tension and changes in posture.