Lumbar spine and hip flexibility and trunk strength in helicopter pilots with and without low back pain history.

BACKGROUND Low back pain (LBP) is one of the most common musculoskeletal issues facing military helicopter pilots. It is clinically important to identify differences in musculoskeletal characteristics between pilots with and without a LBP history for formulating effective interventions. OBJECTIVE To compare lumbar spine and hip flexibility and trunk strength in pilots with and without a LBP history. METHODS A total of 30 pilots with a LBP history were matched with pilots without a LBP history. An isokinetic dynamometer and a digital inclinometer were used to evaluate trunk and hip strength and a range-of-motion (ROM), respectively. All tests were performed bilaterally, if applicable, and agonist/antagonist ratios and side-to-side (low/high) symmetries were calculated. Paired t-tests or Wilcoxon tests were used to assess group differences (p <  0.050). RESULTS The LBP group demonstrated significantly lower trunk extension strength and trunk extension/flexion strength ratio (p <  0.008). The LBP group demonstrated significantly less lateral flexion ROM as well as greater lateral flexion and rotation side-to-side asymmetry (p <  0.009). The LBP group demonstrated significantly greater total hip rotation side-to-side asymmetry (p = 0.037). CONCLUSIONS Given the results, specific exercises that are targeted to improve trunk strength, ROM, and side-to-side symmetries could be developed to reduce LBP in helicopter pilots.