Hip and knee joint kinematics during a diagonal jump landing in anterior cruciate ligament reconstructed females Eamonn Delahunt a,b,⇑ , Anna Prendiville a , Lauren Sweeney a , Mark Chawke a , Judy Kelleher a , Matt Patterson a , Katie Murphy a a School of Public Health, Physiotherapy and Population Science, University College Dublin, Dublin, Ireland b Institute for Sport and Health, University College Dublin, Dublin, Ireland article info Article history: Received 3 July 2011 Received in revised form 16 February 2012 Accepted 16 February 2012 Keywords: Knee ACL Ligament Reconstruction Biomechanics Injury abstract Anterior cruciate ligament (ACL) injury is a common injury encountered by sport medicine clinicians. Surgical reconstruction is the recommended treatment of choice for those athletes wishing to return to full-contact sports participation and for sports requiring multi-directional movement patterns. The aim of ACL reconstruction is to restore knee joint mechanical stability such that the athlete can return to sporting participation. However, knowledge regarding the extent to which lower limb kinematic pro- files are restored following ACL reconstruction is limited. In the present study the hip and knee joint kine- matic profiles of 13 ACL reconstructed (ACL-R) and 16 non-injured control subjects were investigated during the performance of a diagonal jump landing task. The ACL-R group exhibited significantly less peak knee joint flexion (P = 0.01). Significant between group differences were noted for time averaged hip joint sagittal plane (P < 0.05) and transverse plane (P < 0.05) kinematic profiles, as well as knee joint frontal plane (P < 0.05) and sagittal plane (P < 0.05) kinematic profiles. These results suggest that aberrant hip and knee joint kinematic profiles are present following ACL reconstruction, which could influence future injury risk. Ó 2012 Elsevier Ltd. All rights reserved. 1. Introduction Anterior cruciate ligament (ACL) rupture is a common injury encountered by clinicians involved in the prevention, treatment and rehabilitation of sports injuries. The ACL functions to provide mechanical stability to the knee joint by providing restraint to excessive anterior tibial translation as well as frontal and trans- verse plane movements (Andersen and Dyhre-Poulsen, 1997). The ACL, in addition to its role in providing mechanical stability to the knee joint also plays an integral role in knee joint sensorimo- tor control and proprioception (Johansson et al., 1991). Thus, rup- ture of the ACL can negatively influence knee joint function (Bonfim et al., 2003). The aim of ACL reconstruction surgery is to restore knee joint mechanical stability such that the athlete can return to sporting par- ticipation. However, full restoration of knee joint function following ACL reconstruction is often limited, and future complications such as the development of knee joint osteoarthritis (Chaudhari et al., 2008), future knee joint injury (Waldén et al., 2006) and re-rupture are of particular concern (Shelbourne et al., 2009). Reports in the literature suggest that female athletes have a higher incidence of non-contact ACL injuries when compared to male athletes participating in the same sports (Agel et al., 2005; Waldén et al., 2011). A high proportion of ACL injuries in female athletes are non-contact in mechanism and occur during sporting activities such as twisting, cutting and single-leg landing (Olsen et al., 2004; Krosshaug et al., 2007). Specific biomechanical mea- sures that have been reported to contribute to the ACL injury mechanism in female athletes include, an increased knee valgus angle, and decreased knee flexion range of motion (Myer et al., 2011). Furthermore, a recent model-based image-matching study by Koga et al. (2010) indicated that ACL injury is characterized by a low knee flexion angle during initial contact followed by a sudden increase in knee joint valgus angular displacement. Traditionally the success of ACL reconstruction has been as- sessed in terms of the anterior tibial translation (Daniel et al., 1985; Jonsson et al., 1993) and rotational laxity (Musahl et al., 2007; Lorbach et al., 2009) present following reconstruction. These methods of assessment measure passive knee joint laxity and do not replicate the loading patterns experienced during dynamic functional activities. Recently numerous studies has examined knee joint biomechanics during various activities such as walking (Butler et al., 2009; Gao and Zheng 2010) and pivoting tasks (Ristanis et al., 2005; Claes et al., 2011; Lam et al., 2011). Two more 1050-6411/$ - see front matter Ó 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.jelekin.2012.02.009 ⇑ Corresponding author. Address: School of Public Health, Physiotherapy and Population Science, University College Dublin, Health Sciences Centre, Belfield, Dublin 4, Ireland. Tel.: +353 1 7166671. E-mail address: eamonn.delahunt@ucd.ie (E. Delahunt). Journal of Electromyography and Kinesiology 22 (2012) 598–606 Contents lists available at SciVerse ScienceDirect Journal of Electromyography and Kinesiology journal homepage: www.elsevier.com/locate/jelekin