99 - Low back pain and lumbar degeneration in Japanese professional baseball players

Introduction
Acute and chronic low back pain in professional baseball players is a cause of poor performance, and therefore, accurate diagnosis and appropriate treatment are required.
Purpose
In this study, we evaluated the lumbar spine diseases and operation in Japanese professional baseball players.
Methods
Thirty two patients, 18 fielders and 14 pitchers, who were referred to our hospital for treatment, were included (21 in their 20s and 11 in their 30s). We evaluated the cause of low back pain. Due to survey lumbar degeneration, Phirrmann grade, Schmorl's node and Modic changes were evaluated using MRI. The surgical procedure and the rate of return to competition were investigated.

Results:
The most frequent causes of low back pain among players in their 20s were lumbar disc herniation (57%) and spondylolysis (24%). Those among players in their 30s were discogenic pain (55%) and lumbar disc herniation and facet joint arthritis (each 18%). We investigated the prevalence of professional baseball players with two or more degenerated intervertebral discs (grade 3 or higher). The prevalence of lumbar intervertebral disc degeneration was significantly higher in players in their 30s (91%) than in their 20s (14%), as was the prevalence of Schmorl’s node (5% in their 20s; 36% in their 30s) and Modic type 1 change (5% in their 20s; 45% in their 30s). There was no significant difference in the cause of low back pain or the prevalence of lumbar intervertebral disc degeneration between pitchers and fielders. Surgical treatment was performed on 13 patients. Nine patients underwent full endoscopic treatment (FED), and the remaining four patients underwent FED and MED. All players were able to return to the competition.
Discussion
Among professional baseball players in their 20s, lumbar degeneration occurred less frequently than among players in their 30s, and those in their 20s often developed diseases that were less related to degeneration, such as lumbar disc herniation. On the other hand, among players in their 30s, lumbar degeneration was more advanced and degenerative diseases such as discogenic pain occurred more frequently. We believe that further research on training methods can lead to preventive measures against LBP.
Conclusion
These data may also be applicable to other professional athletes and will contribute to diagnosis and treatment. In addition, professional baseball players have a high need for minimally invasive surgery. All patients have undergone FED surgery and have returned to the competition. FED surgery was considered to be high patient satisfaction.