Abstract
Introduction:
It is unknown whether functional and isokinetic testing at 6 months following ACL reconstruction in patients with open-physes correlates with longer term outcomes. The purpose of this study was to compare subsequent ACL rupture risk, knee function, and activity level in patients with open-physes who had excellent 6-month testing to those who did not.
Methods:
Between the years of 2000 and 2015, 86 patients with open-physes underwent ACL reconstruction and had functional and isokinetic testing performed at 6-months post-operatively. Thirty-four (40%) tested in the excellent range in all categories of both functional and isokinetic testing and were labeled the excellent group. The remaining 52 (60%) patients were labeled the delayed testing group. Data regarding patient, injury, and surgical characteristics were retrospectively collected. The rate of second ACL injury as well as clinical outcome scores were collected postoperatively.
Results:
Graft rupture rate was 23.4% (n = 8) in the excellent group and 15.4% (n = 8) in the delayed group (p = 0.51). In the excellent group, 20.5% (n = 7) had a contralateral ACL tear versus 11.5% (n = 6) in the delayed group (p = 0.40). Five patients in the excellent group and 4 patients in the delayed group sustained both graft failure and contralateral ACL tear. The overall prevalence of second ACL injury was 29% in the excellent group and 23% in the delayed group. The delayed group returned to sport at an average of 8.8 months whereas the excellent group returned at an average of 6.6 months (p < 0.01). At mean follow up of 3.59 years, the excellent group had a higher Tegner activity level (8.9 versus 8.3) than the delayed group (p < 0.02).
Conclusion:
Pediatric patients with open-physes who had excellent isokinetic strength and functional testing 6-months postoperatively returned to sport sooner than those who did not. There was no statistical difference in either graft failure or contralateral ACL disruption between these groups. However, both groups had unacceptably high rates of second ACL injury (29% for the excellent group and 23% for the delayed group).
Significance:
Excellent 6 month return of strength and function was not protective of subsequent ACL disruption, the rate of which remains dismal within this pediatric population. Development of more sensitive functional measures for children could help to change these poor outcomes and guide clinicians when to allow return to sport.