Effects of a Knee Ligament Injury Prevention (KLIP) Program on the Incidence of Non-Contact ACL Injury: A Two-Year Study of Exercise Intervention in High School Female Athletes
Authors:
Ronald P Pfeiffer EdD, ATL, ATC, Boise State University, Boise, ID
Kevin G. Shea MD, Intermountain Orthopaedics, Boise, ID
Sara Grandstrand BS, ATC, Boise State University, Boise, ID
Dana Roberts BS, ATC, Boise State University, Boise, ID
Objective: Studies have suggested that exercise programs can reduce the incidence of non-contact ACL injury in female athletes.(1,2) The limitations of these previous studies include: 1) measures of program compliance were not performed, 2) limitations in data collection for injury exposure and for knee injury rates. Our study has attempted to address these design flaws. We conducted a two-year prospective study on ACL injury in females that was implemented in August of 2001 and concluded in March of 2003.Methods: High school female athletes from a defined geographic area were entered into a two-year prospective study. Three sports were evaluated (Soccer, Volleyball, Basketball). The schools were divided into two groups: 1) Intervention Group--Participation in a plyometric/strengthening (KLIP) program twice a week throughout the season, and 2) Control Group--Non-participation in the plyometric/strengthening program. The athletic trainer and coach at each participating school received training in the implementation of the program. Coaches and/or athletic trainers conducted weekly monitoring of participation in the intervention program for each athlete. Weekly participation in practice and games was recorded for all athletes. The athletic trainer and an orthopaedic surgeon evaluated all serious knee injuries. Suspected non-contact ACL injuries were confirmed by history along with surgery and/or MRI.Results: 11 high schools participated in the first year of the study and 12 in the second year. There were three confirmed non-contact ACL injuries in the intervention schools and four such injuries in the control schools. Average weekly exposures and numbers of participants in both groups were used to calculate an odds ratio between intervention and control schools, after collapsing within school, team and level (varsity, junior-varsity, sophomore, etc.). The calculated odds ratio was not statistically significant.Conclusions: Our study has a relatively high number of athletes and practice/game exposures, and is comparable to other studies. The strengths of this study include improved data collection related to exposure and participation in an exercise program. Our results suggest that exercise/strengthening programs may not have a significant effect on reducing the incidence of ACL injury in female athletes.References:
Hewett, TE, et al. (1999). The effect of neuromuscular
training on the incidence of knee injury in female athletes—a prospective
study. AJSM, Vol.27(6), pp. 699-705.
Caraffa, A, et al. (1996). Prevention of anterior cruciate ligament injuries in soccer – a prospective controlled study of proprioceptive training. KSSTA, Vol. 4, pp. 19-21.
Acknowledgements: Funding for this study was provided by St. Alphonsus Orthopaedic Institute, Boise, ID
