Impact of Hamstring Graft on Hamstring Peak Torque and Maximum Effective Angle After Anterior Cruciate Ligament Reconstruction: An Exploratory and Preliminary Study
Abstract
1. Introduction
2. Methods
2.1. Study Design
2.2. Randomization
2.3. Participants
2.4. Sample Size Calculation
2.5. Rehabilitation Protocol
2.6. Assessment Protocol
2.7. Statistical Analysis
3. Results
3.1. Participant Characteristics
3.2. Maximum Effective Angle
3.2.1. Comparison Between Test and Control Groups
3.2.2. Within-Group Comparison (Test Group)
3.3. Hamstring Peak Torque
3.3.1. Comparison Between Test and Control Groups
3.3.2. Within-Group Comparison (Test Group)
3.4. Hamstring-to-Quadriceps Strength Ratio
3.4.1. Comparison Between Test and Control Groups
3.4.2. Within-Group Comparison (Test Group)
3.4.3. Correlation Between MEA and Hamstring Peak Torque
4. Discussion
4.1. Maximum Effective Angle
4.2. Hamstring Peak Torque Deficits
4.3. Hamstring-to-Quadriceps Strength Ratio
4.4. Correlation Between MEA and Hamstring Peak Torque
5. Limits
6. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Characteristic | Control Group (n = 20) | Test Group at 3 Months (n = 20) | Test Group at 6 Months (n = 20) | p-Value |
---|---|---|---|---|
Age (years) | 27 (±5.46) | 26.25 (±8.14) | 26.50 (±8.14) | 0.64 |
BMI (kg/m2) | 24.05 (±3.57) | 23.50 (±3.30) | 23.50 (±3.30) | 0.53 |
Sex (Male/Female) | Male: 10/Female: 10 | Male: 10/ Female: 10 | Male: 10/ Female: 10 | 0.89 |
Side Tested (Left/Right) | Left: 9/Right: 11 | Left: 9/Right: 11 | Left: 9/Right: 11 | 0.78 |
Interval Between Surgery and Assessment (Months) | Ø | 3.37 (±0.42) | 6.21 (±0.40) | Ø |
Time Point | Control Group (n = 20) | Test Group (n = 20) | p-Value |
---|---|---|---|
MEA (°) 3 Months Post-Surgery | 36.4 ± 12.0 | 26.3 ± 8.2 | 0.0019 |
MEA (°) 6 Months Post-Surgery | 36.4 ± 12.0 | 28.2° ± 9.4 | 0.037 |
Time Point | Test Group at 3 Months (n = 20) | Test Group at 6 Months (n = 20) | p-Value |
---|---|---|---|
MEA (°) | 26.3 ± 8.2 | 28.2 ± 9.4 | 0.089 |
Time Point | Control Group (n = 20) | Test Group (n = 20) | p-Value |
---|---|---|---|
HPT (Nm) 3 Months Post-Surgery | 73.9 ± 36.7 | 55.4 ± 34.5 | 0.081 |
HPT (Nm) 6 Months Post-Surgery | 73.9 ± 36.7 | 80.3 ± 30.6 | 0.067 |
Time Point | Test Group at 3 Months (n = 20) | Test Group at 6 Months (n = 20) | p-Value |
---|---|---|---|
HPT (Nm) | 55.4 ± 34.5 | 80.3 ± 30.6 | 0.0094 |
Time Point | Control Group (n = 20) | Test Group (n = 20) | p-Value |
---|---|---|---|
H/Q Ratio (%) 3 Months Post-Surgery | 63 ± 14 | 51 ± 12 | 0.027 |
H/Q Ratio (%) 6 Months Post-Surgery | 63 ± 14 | 56 ± 13 | 0.034 |
Time Point | Test Group at 3 Months (n = 20) | Test Group at 6 Months (n = 20) | p-Value |
---|---|---|---|
H/Q Ratio (%) | 51 ± 12 | 56 ± 13 | 0.041 |
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Bouzekraoui Alaoui, I.; Moiroux-Sahraoui, A.; Mazeas, J.; Kakavas, G.; Biały, M.; Douryang, M.; Forelli, F. Impact of Hamstring Graft on Hamstring Peak Torque and Maximum Effective Angle After Anterior Cruciate Ligament Reconstruction: An Exploratory and Preliminary Study. Bioengineering 2025, 12, 465. https://doi.org/10.3390/bioengineering12050465
Bouzekraoui Alaoui I, Moiroux-Sahraoui A, Mazeas J, Kakavas G, Biały M, Douryang M, Forelli F. Impact of Hamstring Graft on Hamstring Peak Torque and Maximum Effective Angle After Anterior Cruciate Ligament Reconstruction: An Exploratory and Preliminary Study. Bioengineering. 2025; 12(5):465. https://doi.org/10.3390/bioengineering12050465
Chicago/Turabian StyleBouzekraoui Alaoui, Ismail, Ayrton Moiroux-Sahraoui, Jean Mazeas, Georgios Kakavas, Maciej Biały, Maurice Douryang, and Florian Forelli. 2025. "Impact of Hamstring Graft on Hamstring Peak Torque and Maximum Effective Angle After Anterior Cruciate Ligament Reconstruction: An Exploratory and Preliminary Study" Bioengineering 12, no. 5: 465. https://doi.org/10.3390/bioengineering12050465
APA StyleBouzekraoui Alaoui, I., Moiroux-Sahraoui, A., Mazeas, J., Kakavas, G., Biały, M., Douryang, M., & Forelli, F. (2025). Impact of Hamstring Graft on Hamstring Peak Torque and Maximum Effective Angle After Anterior Cruciate Ligament Reconstruction: An Exploratory and Preliminary Study. Bioengineering, 12(5), 465. https://doi.org/10.3390/bioengineering12050465