Cutting Technique of Soccer Players After ACLR: On-Field Matched Control Study

Background: Anterior cruciate ligament (ACL) ruptures in soccer most commonly occur during cutting maneuvers with noncontact injury mechanisms. Biomechanical assessment of the cutting technique has become a critical component of return-to-sport (RTS) evaluation after ACL injury, particularly in young football players at elevated risk of reinjury. However, the cutting technique in players with ACL reconstruction (ACLR) has never been examined under sport-specific conditions. Purpose/Hypothesis: This study aimed to evaluate the cutting technique in pediatric soccer players who had ACLR after RTS clearance against matched healthy controls during on-field soccer (or football)-specific (FS) movements. It was hypothesized that players with ACLR would exhibit risk factors for ACL injury and biomechanical differences relative to healthy counterparts. Study Design: Case-control study; Level of evidence, 3. Methods: A total of 61 young soccer players—21 with ACLR (age, 16.7 ± 1.5 years) and 40 healthy matched controls—performed planned and unplanned FS cutting tasks on a regular soccer pitch. Kinematics of the lower limbs, pelvis, and trunk were collected using 8 wearable inertial sensors. Cut-stance phase kinematics were extracted as peak values, range of motion (ROM), initial contact values, and peak knee flexion. A linear mixed-effects model tested the effects of injury (β 1 , ACLR vs healthy), limb (β 2 , injured/dominant vs noninjured/nondominant), and their interaction effect (β 2 + β 3 , injury × limb) on kinematics ( P < .05). Results: Significant injury × limb interactions ( R 2 : 0.02-0.41; P < .001- P < .046) indicated altered kinematics in players with ACLR compared with healthy controls. Players with ACLR showed greater peak hip flexion (β 1 = 22.2°), knee valgus (β 1 = 2.3°), and lower knee flexion (β 1 = −2.6°) during the unplanned FS task. Players with ACLR also showed reduced lower limb flexion ROM (β 1 = −19.6° to −10.6°) but greater pelvis and trunk flexion ROM (β 1 = 2.2° to 4.8°) during unplanned FS task and greater contralateral pelvic drop and trunk tilt (β 1 = −2.9° to −3.7°) in both tasks. Conclusion: Players with ACLR showed biomechanical alterations during field-based sport-specific cutting maneuvers compared with matched healthy controls, despite RTS clearance.