How characteristics of swinging mechanics can lead to low back pain for golfers

Inherent downsides of golf's popularity
Due to its minimal level of physical stress and intensity, golf is an extremely popular activity enjoyed by more than 55 million people of all ages and skill levels throughout the world, a number that continues to increase regularly. Despite its low-key nature, however, injuries in golf still occur, with low back pain (LBP) being the most common complaint for both professional and amateur golfers. LBP injuries are usually defined as those that prevent participation in golf for 10 weeks or more per incident, with the potential to cause further health complications in the older population. These injuries have caused particular interest in the PT community, which has been investigating the specific dynamics that cause LBP and working to establish programs that treat and prevent these occurrences in golfers. Since the golf swing produces considerable mechanical forces and includes a number of different motions involving the trunk and hip, improper swing mechanics are assumed to be the cause of injury. To better understand the kinematics and kinetics of the trunk during the golf swing, golfers with and without LBP were compared side-by-side and evaluated for telltale characteristics in their swing.

Analyzing golf swing characteristics to a 'tee'
The study was comprised of two groups: one consisted of 16 male golfers with a history of mechanical LBP resulting from golf within the past two years, and the other contained 16 male golfers with no history of LBP. Kinematics and spinal loads of the trunk were assessed using the Vicon Motus system and reflective markers placed at important locations on each participant's body and on the golf club. Participants were instructed to perform a self-selected warm-up of swings, stretches and practice shots, and results were recorded. Trunk and hip muscle strength was assessed using the Biodex System III, with subjects performing five repetitions at 60º/s and 120º/s for both trunk rotation and flexion/extension, and isokinetic strength of trunk rotation and trunk flexion/extension tested in both a seated and semi-standing position. Hip range of motion (ROM) was measured using a standard goniometer by an experienced PT, hamstring flexibility was evaluated using the active knee extension test and postural stability was assessed using a Kistler force plate and a barefoot single-limb standing balance task.

Minor differences between groups that can have future implications
Results showed that the group with a history of LBP had significantly less maximum trunk rotation angle toward the non-lead side measured actively in neutral standing position than the group without LBP. The group with LBP also showed significantly less trunk extension strength at 60º/s and less left hip adduction strength than the other group. On the other hand, no significant differences were found for the kinematic variables and the maximum moments about the three anatomical axes at the L5-S1 level between the two groups, and there was also no significant difference in estimated driving distance between groups.

The finding that golfers with a history of LBP had less back extension strength at the speed of 60°/s could be one indicator of a hindrance on golf swing, since a flexed trunk angle must be maintained to make a proper turn back and return to the ball. The other deficits of less hip adduction muscular strength and of less trunk rotation motion may be theorized as having an affect on the dissipation of spinal loads generated by the golf swing over time. As a result, injury can occur. Unfortunately, it is unknown if the deficiencies found in the group with a history of LBP contributed to the back injury or were actually results of the injury. Therefore, these physical characteristics must be evaluated in more detail to determine the exact role they play in LBP-related injury. In the meantime, it's suggested that a comprehensive exercise program that focuses on trunk extension strength at slow speed, left hip adduction strength and backswing rotational ROM may improve the observed deficits noted in this study and may impact the incidence or recurrence of LBP as well.

-Summarized by Greg Gargiulo

-As reported in the July '10 edition of the Journal of Orthopaedic & Sports Physical Therapy