Effect of Hamstring Stretching on Pelvic Angle and Biofeedback Pressure during Passive Straight Leg Raising

Abstract

During hip flexion, it is important to distinguish femoral motion from pelvic motion. Because hip joint and pelvis move sequentially during hip flexion, clinicians commonly attempt to detect the onset of pelvic rotation when measuring the range of hip flexion, or to limit pelvic movement when measuring hamstring muscle length. However, previous studies have demonstrated concurrent movement of the femur and pelvis, posterior tilting of the pelvis, and flattening of the lumbar spine during hip flexion; collectively, these movements are termed pelvifemoral rhythm. The contribution of pelvic rotation to hip flexion onsets at a very early point and then persists throughout the range of hip flexion. Thus, clinicians must consider simultaneous pelvifemoral rhythm when measuring the range of hip flexion or hamstring muscle length. In previous studies, pelvic motion accompanying hip flexion was analyzed using various tools, including tape lines or tape markers, spherical reflective markers, 8, 10 and magnetic sensors. However, these tools require time and effort for installation and analysis of the acquired data, Effect of Hamstring Stretching on Pelvic Angle and Biofeedback Pressure during Passive Straight Leg Raising