Temporal and Sex-Related Differences in Knee Biomechanics Over the Course of the Varsity Athletic Season: Pre- and Postseason Knee Kinematics in Collegiate Varsity Athletes Using Kinect
Bibliographic record
Abstract
Background: Anterior cruciate ligament (ACL) tears can be a source of significant morbidity, with the potential for career-altering implications for athletes who sustain them. Specific knee biomechanics during a drop vertical jump have been shown to be associated with an increased risk for ACL injury in collegiate varsity athletes. Presently, the evolution of these kinematics from preseason to postseason is not well-understood. Purpose: To compare preseason and postseason knee biomechanics during a drop vertical jump in collegiate varsity athletes and identify changes in ACL injury risk. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 114 collegiate athletes were prospectively enrolled. Of these 114, 67 athletes (male, 21 [31%]; female, 46 [69%]) completed properly captured preseason and postseason drop vertical jumps tracked by an affordable motion capture system. Initial coronal (IC), peak coronal (PC), and peak sagittal (PS) angles of the knee were compared between preseason and postseason using the Wilcoxon signed-rank test and paired-samples t test. Athletes at high risk for ACL injury were identified based on published cutoff angles: IC angle >2.96°, PC angle >6.16°, and PS angle <93.82°, then the distribution of these athletes was compared. Results: In male athletes, all preseason knee angles were in the low-risk range. At postseason, men presented a nonsignificant reduction in mean IC and PC knee angles and a nonsignificant reduction in mean PS angle (90.88 ± 10.69). On average, female athletes were at high risk at preseason according to mean IC and PS angles (4.24 ± 1.09 and 92.90 ± 6.94, respectively). There was a statistically significant reduction in mean IC angle (mean difference [MD], 2.23; P = .03) and mean PC angle (MD, 0.76; P = .04); however, mean IC angle remained in the high-risk range. There was a nonsignificant reduction in mean PS angle, which remained within the high-risk range (MD, 3.96; P = .24). Conclusion: Our study demonstrated that female collegiate varsity athletes demonstrate higher risk knee biomechanics in comparison with their male counterparts. Even with improved biomechanics as their season advances, female athletes have a persistently low PS angle, leaving them at high risk of ACL injury. Using a portable and reliable motion capture system may facilitate monitoring knee kinematics, which could translate into a tool for ACL injury prevention in athletes.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".