Comparison of Landing Biomechanics in Male Amateur Basketball Players with and without Patellar Tendinopathy during Simulated Games

Abstract

This study compared male amateur basketball players with asymptomatic patellar tendon tendinopathy (ASYM) to healthy controls (CON) during simulated games to explore the differences in patellar tendon force (PTF) and related metrics. Data on kinematics, kinetics, and electromyography were collected from 24 participants, comprising 12 in the ASYM group and 12 in the CON group, performing a stop-jump task in four stages (1^st, 2^nd, 3^rd, 4^th). A musculoskeletal model was used to calculate PTF, and Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA) identified significant variables. In the first three stages, the ASYM group showed significantly greater PTF and the ankle discrete relative phase (ADRP) than the CON group, with differences of 0.98, 0.79, 0.81kg•BW^-1 (p < 0.001) and 7.34°, 11.24°, and 2.49° (p < 0.05), respectively. In the last three stages, the ASYM group had a higher knee co-activation index (KCAI) than the CON group, with differences of 0.33, 0.28, and 0.25 (p < 0.05). Correlations between PTF and the ADRP and between PTF and the KCAI were the highest, at 0.58 and 0.61, respectively. The OPLS-DA model effectively distinguished between the groups, suggesting potential applications in tendon health monitoring. The findings suggest that elevated PTF may be linked to tendinopathy in male amateur basketball players, highlighting the importance of comprehensive strategies, such as improving ankle symmetry and optimizing muscle coordination to mitigate tendon load and injury risk.

Keywords: guards; injury prevention; orthogonal partial least squares-discriminant analysis; patellar tendon force; simulated basketball load.

Figure 1

Diagram of data acquisition. (A) Diagram of the stop-jump test. (B) The schematic depiction of the Basketball Exercise Simulation Test. High indicates the high-intensity shuffling; Low indicates the low-intensity shuffling. (C) Experimental procedure.

Figure 2

Bland-Altman consistency evaluation plot of the musculoskeletal model. Note: Red dashed lines represent a 95% confidence interval for the difference between measurement methods and red solid lines represent the average of the difference between the two measurement methods

Figure 3

Detailed distributions of the correlation coefficient values between variables. PTF: patellar tendon force; HDRP: hip discrete relative phase; KDRP: knee discrete relative phase; ADRP: ankle discrete relative phase; KAV: left knee joint angular velocity; KS: knee joint stiffness; KCAI: knee joint co-activation index; ACAI: ankle joint co-activation index; BF, GM, PL, RF, SM, TA, VL, VM: IEMG contribution rates of each muscle

Figure 4

Performance evaluation and validation of the OPLS model; (A) model performance metrics; p1 indicates the model’s predictive component; o1 indicates the orthogonal component 1; o2 indicates the orthogonal component 2; (B) permutation test for model validation; (C) observation diagnostics; (D) scores plot from the OPLS model; blue indicates the ASYM group, and red indicates the CON group.