More than 12 million Americans over age 50 have osteoporosis and over 50 million more have low bone density (osteopenia), putting them at risk for osteoporosis.

Paget’s disease, also known as osteitis deformans, is the second most common bone disorder in the United States (behind osteoporosis).

Spinal tumors, also called neoplasms, are abnormal growths of tissue found inside the spinal column.

Pinched spinal nerves can develop suddenly or gradually. Sudden compression usually occurs in the setting of an acute joint problem called a “herniated disc,” also discussed in more detail elsewhere.

“Arthritis” is an umbrella term used to explain inflammation, joint pain and joint disease in one or more joints. There are more than 100 types of arthritis, and RA is the second-most common.

Sacroiliac (SI) joint dysfunction is a common cause of low back pain.

An alteration in scapular positioning or motion can make it difficult to move your arm, especially when performing overhead activities, and may cause your shoulder to feel weak.

One particular type of kyphosis is Scheuermann’s kyphosis, also known as Scheuermann’s disease.

Sciatica may feel like a bad leg cramp, with pain that is sharp ("knife-like"), or electrical. The cramp can last for weeks before it goes away.

When low back pain radiates through the buttocks and down the leg, the symptoms are known as sciatica.