Lumbo-Pelvic Biomechanics and Quadratus Lumborum Asymmetry in Cricket Fast Bowlers

CREWE, H., A. CAMPBELL, B. ELLIOTT, and J. ALDERSON. Lumbo-Pelvic Biomechanics and Quadratus Lumborum Asymmetry in Cricket Fast Bowlers. Med. Sci. Sports Exerc., Vol. 45, No. 4, pp. 778-783, 2013. Purpose: This study aimed to analyze lumbo-pelvic lateral flexion kinematics and kinetics in junior fast bowlers and compare bowlers with varying quadratus lumborum (QL) cross-sectional area (CSA) asymmetry profiles. Methods: Magnetic resonance imaging was used to determine QL CSA of 39 participants who also underwent three-dimensional analysis of their bowling action. Results: Bowlers with greater than 10% QL asymmetry (n = 26) experienced a larger peak lumbo-pelvic lateral flexion; angle (21.6 degrees +/- 4.2 degrees), angular velocity (314.9 degrees.s(-1) +/- 86.6 degrees.s(-1)), moment (12.8 +/- 2.5 N.m.kg(-1).m(-1)), positive power (25.6 +/- 12.6 W.kg(-1).m(-1)), and negative power (48.6 +/- 20.9 W.kg(-1).m(-1)) compared with the bowlers with less than 10% asymmetry (n = 13) (angle = 18.1 degrees +/- 1.9 degrees, angular velocity = 243.8 degrees.s(-1) +/- 64.9 degrees.s(-1), moment = 10.4 +/- 2.8 N.m.kg(-1).m(-1), positive power = 14.7 +/- 7.4 W.kg(-1).m(-1), and negative power = 33.8 +/- 17.7 W.kg(-1).m(-1); P < 0.05). Conclusion: Fast bowlers with QL CSA asymmetry in excess of 10% experience increased lumbo-pelvic lateral flexion loads during bowling. As increased lateral flexion loads may increase the risk of spondylolysis development, the presence of large QL asymmetry may be a useful screening tool for identifying bowlers at risk of developing lumbar spondylolysis.