Risk factors for lumbar disc degeneration in high school american football players: A prospective 2-year follow-up study
Nagashima M, Abe H, Amaya K, et al. Am J Sports Med. 2013;41(9):2059-2064.
Take Home Message: The presence of Schmorl nodes, disc herniation and playing a lineman position significantly increases the risk of disc degeneration. Continuing to play football for two years is a risk factor for the development of low back pain.
Low back pain and degenerative disc disorder are common chronic injuries that occur during athletics and persist for a lifetime. Identifying the risk factors that cause these conditions can allow for early detection and proper treatment. This study aimed to identify risk factors for disc degeneration in high school American football players and the incidence of low back pain. Several factors were examined including: body mass index, lumbar spine abnormalities, football position played, and length of playing career (2 years or less than 2 years). 192 students were on the football team between 2004 and 2008. 160 participants played for two complete seasons and 32 participants stopped playing before completing 2 seasons. All players received baseline lumbar radiographs and magnetic resonance images (MRIs) when they joined the team. Follow-up radiographs and MRIs were done at the completion of two seasons. The authors used the 32 participants who did not complete the two football seasons as controls. Signal intensity of the nucleus pulposus on the baseline and follow-up MRIs were used to evaluate disc degeneration. The mean signal intensity of the nucleus pulposus decreased from baseline to follow-up among participants who played for two years but not among those who quit. Participants who played lineman position or had a Schmorl node or disc herniation at baseline tended to have more disc degeneration than their peers in other positions or without baseline Schmorl nodes or herniations. Continuing players presented with more mild low back pain than noncontinuing players.
Football is a game of hits and tackles. Lineman take hits every play, which exposes their spine to repetitive loads. This may lead to more cases of disc degeneration. If we can detect early disc degeneration this may enable us to intervene and reduce the risk of pain later in life. Continuing to play football is related to more low back pain possibly due to sports-related mechanical stress. Degenerative discs may affect the onset of low back pain if the disc degeneration continues. This study looked at only one team of high school football players with no true control group. This makes the results of the study difficult to apply to all football teams or other sports. The cause(s) of low back pain still need to be identified and studied further. If possible, collegiate and professional football players should be screened for disc degeneration providing baseline measures in the event of an injury. Overall, this study should raise our awareness that playing a lineman position or the baseline presence of Schmorl nodes or disc herniations may be risk factors in disc degeneration among high school American football players. Applying these finding to the clinical setting, athletic trainers, doctors, and other medical personnel may try to reduce the risk of disc degeneration among lineman and players with baseline lesions by reminding coaches and athletes about proper hitting technique. We can also encourage them modify lifting programs and practice drills to reduce the stress placed on the spine. Head down tackling should also be avoided and can be monitored by the number of marks on linemen helmets.
Questions for Discussion: The high school season is shorter than the college season and both are shorter than the professional season, what do you think the back looks like in those populations? Will technology find a way to regenerate discs that are degenerative? As clinicians, how do you handle athletes with low back pain? Can we keep them playing their sport and playing it successfully?
Written By: Franki Gironda
Reviewed By: Lisa Chinn and Jeffrey Driban