Influence of carrying a backpack on pelvic tilt, rotation, and obliquity in female college students.

The purpose of this investigation was to examine the influence of different methods of backpack carriage on pelvic tilt, obliquity and rotation of college-age females. Thirty subjects (mean age 22.4 years) participated in three conditions: walking without a backpack, carrying a backpack unilaterally, and carrying a backpack over both shoulders. The backpack was loaded with material that comprised 15% of the subject's body weight. Gait was analyzed using the Oxford Metrics VICON Clinical Manager system while the subject walked with no backpack, with a backpack unilaterally and bilaterally. Repeated measures analysis of variance was used to determine differences in angular motion and range of motion in pelvic tilt, rotation, and obliquity in three complete trials during the three walking conditions. Angular pelvic tilt was greatest with bilateral backpack carriage compared to unilateral carriage or walking without a backpack. Angles of pelvic obliquity and rotation were not changed across the three walking conditions. Range of motion for pelvic obliquity and rotation was significantly decreased when walking with a backpack. These results suggest that backpack carriage could cause permanent posture deviations in young female college students. More study is required to evaluate compressive forces during various walking conditions.