RESUMO
More than 40 million individuals participate in organized baseball and softball leagues in the United States every year. Unfortunately, it has also been estimated by the Consumer Product Safety Commission that softball and baseball are the two main sports leading to emergency-room visits in the United States. A previous field study has determined that the utilization of breakaway bases has the potential of preventing 96% of sliding injuries, thereby preventing 1.7 million injuries a year in the United States with a savings of $2 billion a year in health care costs. It is the purpose of this study to analyze and compare the potential attenuating capabilities of various types of bases. We found the force at the ankle upon impact when compared to the standard base revealed all breakaway bases reduced the force of impact to a statistically significant level. The force at the foot upon impact when compared to the standard base revealed all breakaway bases reduced the force at variable levels, with the Rogers bases having the only statistically significant reduction. However, the force delivered to the tibia/fibula was increased with the Stay Down and Mag-Net large bases as compared to the standard stationary base. The moments of inversion/eversion and dorsiflexion/plantar flexion upon impact, when compared to the standard base, revealed all safety bases were reduced to a statistically significant level. We conclude breakaway bases reduce the force of impact and moments to a statistically significant level and confirm previous field studies. Though there is a difference among the breakaway bases themselves, they should be used on all fields.
