Evaluation of Lower Extremity Kinematic Characteristics During Single-Leg Landing from Different Heights in Patients with Knee Valgus Deformity

Shahidi Zahra, Zandi, Mohammadreza Amir-Seifoddini, Mohammadtaghi Amiri-Khorasani, Shahidi Zahra, Mohammadreza Zandi, Mohammadtaghi Amir-Seifoddini, Amiri-Khorasani
2017 J Rehab Med   unpublished
and Aim: Single-leg landing is a common movement in many sports and is known to be an important cause of non-contact Anterior Cruciate Ligament (ACL) injuries that increase knee external motion in the frontal plane. The aim of the current study was to evaluate lower extremity kinematics during single-leg landing from different heights in patients with knee valgus deformity and to compare it with that in healthy individuals. Materials and Methods: A total of 15 female patients with knee valgus
more » ... with knee valgus deformity and 15 healthy female individuals, ranging from 18 to 25 years, were selected to participate in the study. Participants performed single-leg landing from heights of 20, 40, and 60 cm and their actions were monitored using a three-dimensional motion analysis system. After data processing using the CORTEX software, the following parameters were examined: maximum knee valgus angle, maximum knee flexion, maximum dorsiflexion, and duration of eccentric phase. Statistical analysis was carried out using the independent samples t-test and repeated measures analysis of variance at a significance level of less than 0.05. Results: Although the valgus angle in the knee valgus deformity group was greater than that in the healthy group, this parameter did not significantly differ among the different height. Further, the duration of the eccentric phase did not differ significantly between the groups, but maximum knee flexion and maximum ankle dorsiflexion did (P < 0.05). Conclusion: Compared to healthy individuals, those with knee valgus deformities land with lower knee flexion and ankle dorsiflexion angles during single-leg landing from different heights. All the parameters assessed in the present study have been identified as risk factors for ACL injury; therefore, thorough training and correction of the landing pattern should be considered in order to reduce the load applied to the lateral compartment of the knee joint and to prevent deformity progression.