Characterizing the mechanical parameters of forward and backward falls as experienced in snowboarding

Abstract

Wrist injuries are frequently observed after falls in snowboarding. In this study, laboratory experiments mimicking forward and backward falls were analysed. In six different falling scenarios, participants self-initiated falls from a static initial position. Eighteen volunteers conducted a total of 741 trials. Measurements were taken for basic parameters describing the kinematics as well as the biomechanical loading during impact, such as impact force, impact acceleration, and velocity. The effective mass affecting the wrist in a fall also was determined. The elbow angle at impact showed a more extended arm in backward falls compared to forward falls, whereas the wrist angle at impact remained similar in forward and backward falls. The study results suggest a new performance standard for wrist guards, indicating the following parameters to characterize an impact: an effective mass acting on one wrist of 3-5 kg, an impact angle of 75 degrees of the forearm relative to the ground, and an impact velocity of 3 m/s.

Wrist biomechanics during snowboard falls

“…22 Unfortunately, the use of wrist protectors remains relatively low and varies widely around the world, with approximately 17%–42% utilization rates among snowboarders. 23,26,27 However, the rate of wrist protector use was much lower, between 1% and 11%, for injured snowboarders. 4,14,17 In one study, injured snowboarders without wrist protectors were twice as likely to be seen for a wrist injury as those who wore protectors.…”

Trauma Biomechanics

“…Generally a wide spread of data was observed. Hwang et al 2006;Schmitt et al 2012a) are presented. Table 8.2 summarizes further cadaver studies on the loading of the wrist.…”

“…Several parameters were identified that influence the risk of sustaining wrist fracture including the degree of elbow flexion, the impact direction, the impact velocity and the effective mass (Chiu and Robinovitch 1998;Chou et al 2001;DeGoede et al 2002a, b;Kim and Ashton-Miller 2003;Schmitt et al 2012a). The elbow flexion, for instance, has a significant influence on the effective mass that loads the forearm at impact.…”

Numerical study of 10-year-old child forearm injury

“…Based on a literature review, three parameters defining the mechanical responses of backward falls were identified: the effective mass, impact angle, and impact velocity (related to drop height). Schmitt et al (2012) reviewed several studies and reported that the lowest reported effective mass was about 5% of an adult body weight. In the current computational simulation, three different effective masses were tested: 10.8 kg (Greenwald et al (1998), about 1/3 of total body weight of 10-year-old child), 1.62 kg (5% of total body weight of 10-year-old child), and 6.2 kg (the average of the aforementioned effective masses).…”

“…The majority of wrist injuries are consequences of falls. Distal radius fractures on the outstretched arms/hands were observed in both backward and forward falls (Schmitt et al 2012). Several studies have indicated that the risk of sustaining wrist factures can be decreased by wearing a wrist guard (Lewis et al 1997, Machold et al 2002).…”