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Asymmetry in Recreational Athletes One Year After Anterior Cruciate Ligament Reconstruction: Comparison of Isokinetic
Paulina Cárcamo-Aravena1, Joaquín Robledo-Medalla1, Nicolás Yañez1
1Investigation Unit, Alemana Sport Clínica Alemana de Santiago, Santiago, Chile.
Background And Purpose:
After anterior cruciate ligament (ACL) reconstruction, strength and performance asymmetries are widely considered relevant indicators for return to sport; however, the definition of acceptable asymmetry thresholds remains controversial. Here we compare the level of asymmetry in isokinetic knee extensor outcomes and vertical and horizontal single-leg hop tests performance one year after ACL reconstruction in recreational athletes.
Methods:
Cross-sectional study. A total of 32 recreational athletes (females n = 13) one year after ACL reconstruction, with a mean age of 26.21 ± 7.95 years, were included. Peak torque, power, and total work were determined at 60°/s and 180°/s during isokinetic testing. Single-leg hop tests (drop jump and countermovement jump) and vertical hop test (triple hop test) were assessed.
Results:
Significant differences were observed between limbs in all tests (p < 0.05). No differences in asymmetry were found between the isokinetic and vertical hop tests, with asymmetry values ranging between 13% and 18%. The horizontal hop test showed the lowest asymmetry (4%) and exhibited significant differences compared to all other tests (p < 0.05).
Discussion:
Our results indicate that, one year after ACL reconstruction, recreational athletes often continue to exhibit inter-limb asymmetries in isokinetic strength and jump performance that exceed the commonly accepted 10% threshold, except for the horizontal single-leg hop.