Abstract
Background and Objective: The dynamic stability of the knee joint may be influenced by the onset of metabolic fatigue during sports participation, potentially increasing the risk of knee injuries. The present study was conducted with the aim of examining the effect of a fatigue program on the kinematics of lower limb joints in basketball players with dynamic knee valgus pattern in various positions.
Method: In this study, 27 basketball players with dynamic knee valgus deficiency were purposefully selected in three groups: guards (mean age=19/77 ± 2/68 years, mean height= 1/77± 0/04 cm ,and mean weight=63/40 ± 5/10 kg), forwards (mean age=20/22± 2/90 years, mean height= 187± 0/04 cm, and mean weight= 76/80± 2/94 kg ) and centers (mean age=22/33 ± 3/27 years, mean height= 1/99±0/04 cm, and mean weight= 98/84±18/42 kg), within the age range of 16 to 26 years. To evaluate the lower limb angles in the sagittal and frontal planes, imaging was performed using two digital cameras at a distance of 366 centimeters and a height of 105 centimeters relative to the subject, and the subjects performed three counter movement jumps. The analysis was conducted using Kinovea software. A 40-minute basketball game fatigue protocol, including legal breaks, was implemented for fatigue induction. To compare the means of research variables, mixed-design ANOVA (2x3), one-way ANOVA, and Bonferroni post-hoc tests were utilized. All hypothesis tests were conducted at a significance level of 0.05 or less.
Findings: The results revealed that applying the fatigue protocol in the sagittal plane led to a significant decrease in the maximum knee flexion angle in the guard group (p=0.035), initial foot contact in the forward group (p=0.044), and initial foot contact in the center group (p=0.016). Additionally, there was a significant reduction in the maximum plantarflexion of the foot in the center group (p=0.018). In the frontal plane, an increase in the maximum knee valgus of the dominant foot was observed in the center group (p=0.039), and for the non-dominant foot in all three groups: guard (p=0.019), forward (p=0.002), and center (p=0.009). In inter-group comparisons, significant differences were found in initial foot contact between the guard and forward groups (p=0.031) and in the maximum valgus of the dominant foot between the forward and center groups (p=0.041), while no significant differences were observed in other angles.