Feasibility, reliability, and validity of the Modified forward hop test after anterior cruciate ligament reconstruction: Double- instead of single-legged landing is reliable and results in greater hopping distance.

OBJECTIVE: To investigate the feasibility, reliability, and validity of the Modified forward hop 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 two investigators.

PARTICIPANTS: Forty-eight active individuals participated in this study.

MAIN OUTCOME MEASURES: The participants performed Modified forward hops and Forward hops for distance in a predetermined order. The feasibility of the Modified forward hop was quantified with proportions of successfully executed attempts and Pearson's χ² test. Its reliability was estimated using intraclass correlation coefficients (ICC) and standard error of measurements (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 females, 26 (13) months post-surgery) when compared to the Forward hop for distance test (25/288 trials; 9% versus 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 Modified forward hop 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 utilized.