Modified Golf Swing May Reduce Back Injury
It has been documented that up to 62% of golfers may suffer with a game-related injury.  Of those injuries low back pain is the most common.  Most of these golfers are simply swinging incorrectly. 
Many golfers think that the further their shoulders go back during the backswing, the better the swing, and the longer the drive.  Unfortunately this puts the spine in a position of great stress.  A study was done to find if a restricted backswing does indeed prevent injury by eliminating excessive rotation in the spine. 
The results of the study concluded that a backswing shortened by an average of 47 degrees did little to affect club speed or stroke accuracy.  The target spot on the clubhead was also the same.  When they measured EMG (by putting electrodes on the particular muscle groups) it was found that there was 19% less muscle strain to the right external oblique before impact, 12% less activity in the left lumbar during acceleration, 21% less in the right latissimus during activation, and 14% in the left lumbar during follow through.  The EMG activity did increase in the shoulder muscles as the golfers made compensations. 

As much as golfers may not want to change their swing mechanics for fear of decreased game performance, this study showed very no measurable effect to speed or accuracy.  What is important is that the change in the swing can reduce their odds for low back pain.   This may not be indicated for people with shoulder injuries, as it may complicate them.  The authors point out that while the reduced backswing may prevent low back injuries, it may lead to a less severe shoulder issue. 
Bulbulian R, Ball KA, Seaman DR. The short golf backswing: Effects on performance and spinal health implications. Journal of Manipulative and Physiological Therapeutics 2001:24(9), pp. 569-575.

For the latest research in chiropractic, please visit the sites below:
www.activator.com
www.chiro.org/research
nccam.nih.gov/health/chiropractic
http://chiropracticreport.com/portal/index.php?option=com_content&task=view&id=22&Itemid=45
www.jvsr.com/abstracts/abstracts_index.asp