A 2D video-analysis scoring system of 90° change of direction technique identifies football players with high knee abduction moment

Abstract

Purpose Abnormal joint biomechanics and poor neuromuscular control are modifiable risk factors for Anterior Cruciate Ligament (ACL) injury. Although 3D motion capture is the gold standard for the biomechanical evaluation of high-speed multidirectional movements, 2D video analysis is a growing-interest alternative because of its higher cost-effectiveness and interpretability. The aim of the present study was to explore the possible association between a 2D evaluation of a 90° change of direction (COD) and the KAM measured with gold standard 3D motion analysis. Methods Thirty-four competitive football (soccer) players (age 22.8 ± 4.1, 18 male and 16 females) were enrolled. Each athlete performed a series of pre-planned 90° COD at the maximum speed possible in a laboratory equipped with artificial turf. 3D motion analysis was recorded using 10 stereophotogrammetric cameras, a force platform, and three high-speed cameras. The 2D evaluation was performed through a scoring system based on the video analysis of frontal and sagittal plane joint kinematics. Five scoring criteria were adopted: limb stability (LS), pelvis stability (PS), trunk stability (TS), shock absorption (SA), and movement strategy (MS). For each criterion, a sub-score of 0/2 (non-adequate), 1/2 (partially adequate), or 2/2 (adequate) was attributed to the movement, based on objective measurements. The intra-rater and inter-rater reliability were calculated for each criterion and the total score. The Knee Abduction Moment (KAM) was extracted from the 3D motion analysis and grouped according to the results of the 2D evaluation. Results Excellent intra-rater reliability (ICC > 0.88) and good-to-excellent inter-rater reliability (ICC 0.68–0.92) were found. Significantly higher KAM was found for athletes obtaining a 0/2 score compared to those obtaining a 2/2 score in all the sub-criteria and the total score (20–47% higher, p < 0.05). The total score and the LS score showed the best discriminative power between the three groups. Conclusion The 2D video-analysis scoring system here described was a simple and effective tool to discriminate athletes with high and low KAM in the assessment of a 90° COD and could be a potential method to identify athletes at high risk of non-contact ACL injury. Level of evidence IV.

A 2D qualitative movement assessment of a deceleration task detects football players with high knee joint loading

“…The integrated frontal plane assessment (i.e., LS criteria, Table 2 Peak knee abduction moment based on the 2D scoring system Data are expressed in Newton*m/Bodyweight as mean ± standard deviation * Statistically significant differences between the three groups evaluated through the ANOVA (p < 0.05). "GRF vector to knee" means the knee-GRF vector overlay on the frontal plane [12] 2D score Groups…”

“…< 0.001* 1.9 ± 1.0 1.3 ± 0.8 1.2 ± 0.8 GRF vector to knee 0 1 2 < 0.001* 2.0 ± 0.9 1.4 ± 0.7 1.2 ± 0.8 Total score 0-4 5-7 8-10 < 0.001* 1.8 ± 1.0 1.4 ± 0.1 1.1 ± 0.9 Table 3 Multiple comparisons of the knee abduction moment based on the 2D evaluations Differences between the single groups are expressed in Newton*m/ Bodyweight as mean (95% CI) * Statistically significant differences between the single groups evaluated through the t test with Bonferroni correction (p < 0.05). "GRF vector to knee" means the knee-GRF vector overlay on the frontal plane [12] the FPKPA, and the GRF vector) demonstrated great sensibility and specificity for the KAM: only 4% of the athletes were misclassified in the high-KAM group and 2% in the low-KAM group (Fig. 1).…”

“…A 2D scoring system was adopted based on the qualitative movement evaluation of frontal and sagittal plane joint kinematics. Such a scoring system is included in a clinical multiple movements evaluation for RTS decision-making after ACL reconstruction [ 7 , 8 , 12 ]. The test is aimed to identify biomechanical and neuromuscular control deficits providing an intuitive and quick response to the patient.…”

“…All athletes performed six valid repetitions (three right and three left strikes). 3D motion analysis was recorded in a specialized laboratory equipped with artificial turf [12,14]. A set of ten stereophotogrammetric cameras, a force platform embedded in the floor (AMTI 400 × 600, Watertown, MA USA), and three high-speed cameras placed frontally and bilaterally towards movement direction (VICON Nexus, Vicon Motion Systems Ltd, Oxford, UK) were used.…”

“…To facilitate the screening for ACL injury risk in a user-friendly fashion, 2D scoring systems are emerging as a valuable option for complex movement assessment during rehabilitation after ACL injury and reconstruction [ 5 , 12 , 16 , 23 , 26 , 28 ]. These scoring systems have been mainly focused on jump landings [ 5 , 23 , 26 ] and change of direction [ 12 , 16 , 28 ] tasks. To the best of the authors’ knowledge, no 2D assessment method of the deceleration task evaluation has been proposed.…”