Commentary by Shun Torii, a professor at Waseda University School of Sport Sciences
Lower back pain often plagued by professional baseball players. One of the causes is an injury called lumbar spondylolisthesis. Professor Shun Torii of the Waseda University School of Sport Sciences, which specializes in sports injuries during the growth period, explains that “lumbar spondylolisthesis is often caused by exercise during the upper grades of elementary school to junior high school.” Is there a cause or countermeasure?
Lumbar spine separation is a condition in which the ring-shaped structure behind the spine of the lower back, called the “tsuikyu,” is broken and separated.
It is said that many professional baseball players have it, but Mr. Torii asserts that “many of the causes are in the growing season.” In fact, in his own laboratory, MRI examinations were conducted on about 100 junior high school students playing baseball in Tokyo and Saitama prefectures. It is said that about 20% had symptoms of lumbar spine separation.
“When the bones are growing, the muscles are pulled and become stiff and inflexible. Twisting or over-moving the hips at that time can lead to segregation.”
The initial stage begins with a stress fracture. At that point, pain is less likely to occur, and X-rays often do not show clearly. Therefore, it is often left unattended, and in most cases, the symptoms have already progressed to segregation when the pain appears. Then, how should we judge when there is no pain?