On reducing hand impact force in forward falls: results of a brief intervention in young males.
OBJECTIVE
To test the working hypotheses that after a brief (10 min) intervention, (a) young adults can volitionally reduce fall-related wrist impact forces, and (b) no difference in impact force would exist between intervention and control groups at 3-weeks or 3-months follow-up.


BACKGROUND
The wrist is the most commonly fractured site in the body at any age, most often as a result of impact with the ground while arresting a forward fall.Methods. Twenty-nine healthy young male volunteers participated. A 3-month intervention group (n=10) performed five standardized forward falls before and after a 10-min instructional intervention aimed at reducing wrist impact forces during the baseline visit. They, along with a 3-month control group (n=11) who did not receive the intervention, were remeasured in five trials at 3-weeks and 3-months follow-up, without intervening practice. A baseline control group (n=8) performed the five trials, then repeated them at the baseline visit without receiving the intervention. Unilateral body segment kinematics and bilateral hand-ground impact forces were measured and the hypotheses were tested using repeated measures analysis of variance.


RESULTS
At the baseline visit, a significant group-by-trial-block interaction was found (P=0.02): the 3-month intervention group reduced their average maximum impact forces by 18% from initial values (P=0.002); the baseline control group did not do so (0.5% increase, P=0.91). The 3-month intervention (20 falls) and control (15 falls) groups did not differ at the 3-month follow-up (P=0.62); however, when the groups were combined their maximum impact force had decreased significantly (8.9%, P=0.04) over that time.


CONCLUSIONS
Healthy young males learned in 10 min to significantly reduce wrist impact forces in forward falls, but retention was poor at 3-weeks follow-up. Irrespective of group, however, after the 5 falls at 3-weeks subjects had taught themselves to reduce their impact forces at the 3-months follow-up.


CONCLUSIONS
A brief educational intervention can significantly reduce forward fall-related impact forces in the short term. However, with or without the brief intervention, the experience of performing between 5-10 forward falls 3 weeks apart apparently resulted in decreased impact forces over the next 2 months, thereby reducing the risk of injury in these forward falls.
Lo
J
J
Department of Biomedical Engineering, Biomechanics Research Laboratory, GGB 3208, University of Michigan, Ann Arbor, MI 48109-2125, USA.
McCabe
G N
GN
DeGoede
K M
KM
Okuizumi
H
H
Ashton-Miller
J A
JA
D000058:Accidental Falls; D000222:Adaptation, Physiological / Q000502:physiology*; D000328:Adult; D003071:Cognition / Q000502:physiology; D006225:Hand / Q000502:physiology*; D006801:Humans; D008297:Male; D009038:Motion; D010812:Physical Stimulation / Q000379:methods*; D011187:Posture / Q000502:physiology*; D013314:Stress, Mechanical; D014836:Volition / Q000502:physiology; D016474:Weight-Bearing / Q000502:physiology*; D014954:Wrist Injuries / Q000517:prevention & control; D014955:Wrist Joint / Q000502:physiology*