2015 ISAKOS Biennial Congress ePoster #313

Quantitative Improvements in Hop Test Scores Following a 6 Week Neuromuscular Training Program

Adam Stephen Meierbachtol, PT, ATC, Bloomington, MN UNITED STATES
Eric Rohman, MD, Minneapolis, MN UNITED STATES
Eric Paur, PT, ATC, Bloomington, MN UNITED STATES
John Bottom, PT, Bloomington, MN UNITED STATES
Marc Tompkins, MD, Minneapolis, MN UNITED STATES

TRIA Orthopaedic Center, Bloomington , MN, USA

FDA Status Not Applicable

Summary: In addition to improving qualitative movement patterning, this data supports the fact that quantitative improvements in hop tests, both absolute and relative on both affected and unaffected legs, are also possible after completing an intensive six week neuromuscular re-education program following ACL reconstruction.




Intensive neuromuscular re-education (NMR) programs are becoming increasingly popular as they improve qualitative movement patterns which are thought to decrease injury risk following anterior cruciate ligament reconstruction (ACLR). Qualitative improvements, however, do not necessarily improve quantitative results as measured by standardized hop testing. Understanding improvements in hop test scores following NMR could give additional insight into return to play decisions following ACLR.

Our objective was to determine whether completing a six week NMR program following ACLR could improve absolute values, relative percentages, and symmetry between the affected (surgical) and unaffected (non-surgical) legs. Our hypothesis was that both legs would show absolute improvements, but the affected leg would show greater relative improvements compared to the unaffected leg.


Patients self-selected their participation in this six week NMR program which was completed after a full course of formal physical therapy following ACLR. The NMR program, based on work by Myer GD et al Clin Sports Med 2008, meets twice weekly for two hours per session over the course of six weeks. Patients are taken through five stages of progressively challenging plyometric, core strengthening and agility training exercises with special emphasis on proper technique. This was a retrospective analysis of all patients who had undergone unilateral ACLR and completed the NMR program, including pre and post standardized hop testing (n = 128). Hop testing included single leg hop, triple hop, triple crossover hop and timed hop; absolute improvements as well as a comparison of affected to unaffected legs were included. Student’s t-test in absolute and relative improvement was significant when p<0.05.


On the affected leg, pre to post test improvements were seen in single leg hop (53.79 in./61.86 in.), triple crossover hop (141.78 in./164.87 in.), and timed hop (2.30 sec/2.07 sec). On the unaffected leg, improvements were seen in the single leg hop (62.41 in./68.21 in.), triple crossover hop (164.98 in./182.74 in.), and timed hop (2.03 sec/1.88 sec). When comparing affected to unaffected legs, the affected leg improved significantly compared to the unaffected leg in both the single leg hop (17% to 10%) and crossover triple hop (18% to 12%). All values above were significant with p < 0.05.


Completing a six week NMR program is an effective way to improve absolute hop testing measurements on both affected and unaffected legs with single leg hop, crossover triple hop and timed hop reaching statistical significance. Because the affected leg showed a greater absolute and relative improvement compared to the unaffected leg across multiple hop tests, limb symmetry can be improved following completion of this program which may have a protective effect in terms of prevention of re-injury. In summary, in addition to improving movement patterning, this data supports the fact that quantitative improvements in hop tests are also possible after completing a NMR program.