A pilot biomechanical assessment of curling deliveries: is toe sliding more likely to cause knee injury than flatfoot sliding?

Abstract

BackgroundThe aim of this study was to determine whether toe sliding is more likely to cause knee injuries than flatfoot sliding in curling.MethodsTwelve curlers participated in the study, each delivering 12 stones. Six stones per volunteer were delivered using a flatfoot slide and six were delivered using a toe slide. The Pedar-X in-shoe pressure system recorded the plantar pressure during each of the slides, while a sagittal plane digital video recorded the body position of the curler. Measurements were taken from the video recordings using a software overlay program (MB Ruler), and this, combined with the Pedar-X data, gave the overall joint force in the tuck knee.ResultsThe knee joint force for toe sliding was more than double that of flatfoot sliding (p<0.05). There was a strong correlation between the increase in knee joint force and the increase in the moment arm of the ground reaction force. Images produced using the three-dimensional Vicon system confirm that toe sliding produces a larger moment arm than flatfoot sliding.ConclusionInjuries are more likely to occur in toe sliding, compared with flatfoot sliding, due to the increase in force and moment, pushing the weight of the curler forward over the knee, which could make the adopted position less stable. Curlers might consider avoiding toe sliding to reduce the risk of knee injuries if the two types of delivery could be performed equally well.

An examination of studies related to the sport of curling: a scoping review

“…This analysis occurred via an optotrak certus device (Northern Digital Instruments, Waterloo, ON) and a Curling-Specific Balance Test. Biomechanical force analysis was compared between flat-foot and toe sliding with toe sliding producing a larger moment arm than flat-foot sliding ( 12 ). Three of these studies assessed delivery variables according to movement phases ( 54 , 55 , 60 ).…”

“…Both acquired a reportive methodology to assess information on the demographics, site of injury, type of injury, and curling-specific aggravated conditions. A supplemental article (cross-referenced from delivery mechanics) addressed injury in terms of biomechanical delivery measurements according to force vector analysis of delivery positions ( 12 ). Studies concluded that curling is a safe winter sport compared to its Winter Olympic sports counterparts ( 13 , 14 ).…”

“…Delivery mechanics literature further introduced technological devices. Online programs were utilized in terms of measuring kinematic motion ( 58 ), pressure and force vectors ( 12 ), as well as the stone position relative to the line of delivery ( 60 ). From the findings that robotic agents can outperform human curlers in game scenarios, we can accurately store digital curling informatics, and can greatly enhance accuracy in the training and testing of elite-level curlers.…”

“…This comparison was most prevalent in studies regarding delivery biomechanics, in which elite and sub-elite curlers were contrasted in terms of core strength, flexibility, and balance with elite curlers outperforming their sub-elite counterparts ( 57 ). Comparisons also occurred for the center of mass, plantar pressure, and joint angles of elite and sub-elite curling deliveries ( 12 ). Timing methods used to estimate rock displacement were established to be reliable for elite athletes to vary stone delivery velocity, but not for sub-elite ( 56 ).…”

“…Curling delivery mechanics were the main topic of eight studies (12,(54)(55)(56)(57)(58)(59)(60). Delivery variables of flexibility, balance, and core strength were assessed in two studies (57,58).…”