Open Access

Eduard Kurz, Matthias Keller, Wolfgang Schoch, Thomas Stein, Anja Hirschmüller, Daniel Niederer

• Objective: To investigate the feasibility, reliability, and validity of the Modified forward hop (MFH) test in participants after ACL reconstruction (ACLR). Design: Reliability study. Setting: Assessments were administered at different clinical locations in Germany and Switzerland by the same 2 investigators. Participants: Forty-eight active individuals participated in this study (N=48). Main Outcome Measures: The participants performed MFHs and Forward hops for distance in a predetermined order. The feasibility of the MFH was quantified with proportions of successfully executed attempts and Pearson's χ2 test. Its reliability was estimated using intraclass correlation coefficient (ICC) and standard error of measurement (SEM). Test validity was explored using Pearson's product moment correlation analyses. Results: Fewer failed attempts were recorded among the participants (age: 30 [Standard deviation 11] years; 22 women, 26 (13) months post-surgery) when compared with the Forward hop for distance test (25/288 trials; 9% vs 72/288 trials; 25%). Within-session ICC values were excellent (>0.95) for both types of Forward hop tests, independent of the side examined. The SEM values were comparable between the Modified (injured: 5.6 cm, uninjured: 5.9 cm) and the classic Forward hop (injured: 4.3 cm, uninjured: 7.2 cm). Conclusion: The MFH is a feasible, reliable, and valid tool for judging neuromuscular performance after ACLR. If the aim of a hop for distance incorporates enhanced perceived or real landing safety, landing on both feet should be used.