Motor Control Patterns During an Active Straight Leg Raise in Chronic Pelvic Girdle Pain Subjects

Study Design. Repeated measures. Objective. To investigate motor control (MC) patterns in chronic pelvic girdle pain (PGP) subjects during an active straight leg raise (ASLR). Summary of Background Data. The ASLR is a test used to assess load transference through the pelvis. Altered MC patterns have been reported in subjects with chronic PGP during this test. These patterns may impede efficient load transfer, while having the potential to impinge on respiratory function and/or to adversely affect the control of continence. Methods. Twelve female subjects with chronic PGP were examined. Electromyography of the anterior abdominal wall, right chest wall and the scalene, intraabdominal pressure, intrathoracic pressure, respiratory rate, pelvic floor kinematics, and downward leg pressure of the nonlifted leg were compared between an ASLR lifting the leg on the affected side of the body versus the nonaffected side. Results. Performing an ASLR lifting the leg on the affected side of the body resulted in a predominant MC pattern of bracing through the abdominal wall and the chest wall. This was associated with increased baseline shift in intraabdominal pressure and depression of the pelvic floor when compared with an ASLR lifting the leg on the nonaffected side. Conclusion. This MC pattern, identified during an ASLR on the affected side of the body, has the potential to be a primary mechanism driving ongoing pain and disability in chronic PGP subjects.