Findings highlighted biomechanical differences between limbs which are consistent across jump tasks suggesting insufficient rehabilitation at 9 months post surgery. Results indicate that the SLDJ may identify greater performance deficits between limbs than SLHD, which may over-estimate rehabilitation status.

After anterior cruciate ligament reconstruction (ACLR), there is a higher re‐injury rate to the contralateral limb in athletes who undergo surgery using a bone‐patellar‐tendon‐bone (BPTB) autograft than using a semitendinosus and gracilis hamstring tendon (HT) autograft. This may be influenced by differing lower‐limb loading asymmetries present when athletes of each graft type return to play (RTP). The aim of this study was to compare bilateral countermovement jump (CMJ) phase‐specific impulse asymmetries between athletes with BPTB and HT autografts 9 months post‐ACLR, and to identify the relationship between impulse and isokinetic strength asymmetries. Male field sport athletes with a BPTB (n = 22) or HT (n = 22) autograft were tested approximately 9 months post‐ACLR. An uninjured control group (n = 22) was also tested on a single occasion. Phase‐specific bilateral absolute impulse asymmetries were calculated during the CMJ and compared between groups using Kruskal‐Wallis and post‐hoc testing. A linear regression model was used to assess the relationship between impulse asymmetries and isokinetic concentric knee extensor strength asymmetries. BPTB athletes demonstrated greater impulse asymmetries than HT athletes during the eccentric (P = 0.01) and concentric (P = 0.008) phases of the jump. Isokinetic strength asymmetry was a significant predictor of CMJ concentric impulse asymmetry in both BPTB (r2 = 0.39) and HT athletes (r2 = 0.18) but not eccentric impulse asymmetry in any group. The greater loading asymmetries demonstrated by BPTB than HT athletes 9 months after ACLR may contribute to the differing incidence rates of contralateral ACL injury. The findings suggest that graft‐specific loading asymmetries should be targeted during rehabilitation prior to RTP.

research.stmarys.ac.uk/ TITLE Biomechanical but not timed performance asymmetries persist between limbs 9 months after ACL reconstruction during planned and unplanned change of direction AUTHOR King, Enda; Richter, Chris; Franklyn-Miller, Andy; et al.