The link between weather and pain has been reported in many studies. Researchers can’t always explain it, but anyone with arthritis or past joint injury knows when the weather is changing. For example, a drop in atmospheric pressure and increased humidity means more knee joint pain.
Some people with back pain also respond to changes in the weather. These patients have disk problems and a condition known as vacuum phenomenon (VP). VP is a collection of gas in the space between two vertebrae in the spine. This space is called the intervertebral disc space.
As we age, the soft, spongy disc between the vertebrae starts to wear out and degenerate. This process releases a gas that forms a bubble inside the disc space. It’s benign in the sense that it doesn’t cause cancer or death. If it gets large enough, it can press on the spinal nerve and cause painful symptoms.
VP is rare in children but common in adults over 65. It occurs in other parts of the body such as the joints and spinal canal. Pockets of gas also form inside a bone after a fracture. Scientists have found VP in animals, such as dogs and horses.
Patients with disc degeneration and VP are often good predictors of a change in the weather. When VP is present in the disc, there is a problem adjusting to changes in the outside air. The pressure inside the disc becomes high compared to the atmospheric pressure. As a result, changes in the barometric pressure might increase low back pain in patients with VP.