Durations of service until first and recurrent episodes of clinically significant back pain, active component military members: changes among new accessions to service since calendar year 2000.

This report summarizes frequencies and timing of first and recurrent episodes of back pain treated in the U.S. Military Health System among more than 2 million military members who began active service between July 2000 and June 2012. In the population overall, at least 5% were affected by clinically significant back pain within 6 months and 10% within 13 months of beginning active service; and 34% had at least one episode of back pain while in active service during the surveillance period. After initial episodes of back pain, more than half (54%) of those affected had at least one recurrent episode; and after first recurrences, 65% had second recurrences while still in active service. In general, back pain episode-free periods preceding initial and between successive episodes markedly decreased during the period. Frequencies and timing of back pain episodes varied in relation to service branch, gender, and occupation. Acute back pain is a common disorder that is unpredictable in onset and often debilitating. Its prevention should be a military medical research objective of high priority.