Background: Patellar tendinopathy is an overuse injury associated with loading activities, and it is thought to be caused by repetitive force applied to the patellar tendon. Patellar tendinopathy is popular among basketball and volleyball players, particularly in men. Although altered biomechanical characteristics during landing has been suggested as one of the risk factors for the development of patellar tendinopathy, previous evidence failed to show the link between the sagittal plane biomechanics of the hip and knee joint and patellar tendinopathy; and little was known about the frontal and horizontal plane biomechanics in athletes with patellar tendinopathy. Among those factors contributing to the biomechanical characteristics, hip and quadriceps strength were shown linked with the presence of patellar tendinopathy, while other factors such as motor control or muscle activation have not been explored fully. The purpose of this study is to compare hip motor control and biomechanical characteristics of the hip and knee joint during landing in athletes with and without symptomatic patellar tendinopathy. The investigators hypothesize that the athletes with symptomatic patellar tendinopathy have poorer motor control and different landing biomechanics as compared with asymptomatic athletes.~Method: the investigators plan to recruit seventeen symptomatic patellar tendinopathy athletes for the experimental group, using demographic data (sex, age, height, weight, exercise type) of experimental group to match seventeen non-symptomatic athletes as control group. The assessment included hip motor control in various directions, and measurement of kinetics, kinematics and muscle activation during the step-down task, drop vertical jump and countermovement jump using the computer-aided video motion analysis system (Vicon) and the surface EMG (Delsys). The group difference will be tested using Mann-Whitney U test for the score of motor control test battery, and MANOVA for the biomechanical characteristics. The significant level was set at 0.05.
Patellar tendinopathy (PT) is an overuse injury associated with loading activities, and popular among basketball and volleyball players. Although altered biomechanical characteristics during landing has been suggested as one of the risk factors for the development of PT, previous evidence failed to show the link between the sagittal plane biomechanics of the hip and knee joint and PT; and little was known about the frontal and horizontal plane biomechanics in athletes with PT. While other factors such as motor control or muscle activation also have not been explored fully. The purpose of this study is to compare hip motor control and biomechanical characteristics of the hip and knee joint during landing in athletes with and without symptomatic PT.