Impact properties of floor coverings and their role during simulated hip fractures

Fractures of the hip are common among the elderly and preventative measures should be taken to reduce the risk. Hip protectors are a cost-effective solution and can be used successfully to reduce the likelihood of hip fracture. Unfortunately, they suffer from low patient compliance because they are uncomfortable to wear and require co-operation from the patient to wear them consistently. An alternative solution is to place a protective layer on the other impacting surface, which is the floor. This avoids the problem of patient compliance and ensures protection. Little research has been concerned with the role of floor coverings in an impact. A mechanical test rig has been designed and built to simulate a person falling onto floor coverings with sufficient impact energy to fracture the proximal femur if unprotected. Forces are measured using a piezoelectric load cell that is positioned under a pin to represent the greater trochanter. Both the time and frequency domain data have been analysed for each impact. Carpet and vinyl floor coverings have been tested with various underlay materials. The new underlay materials have been compared with typical carpet underlay. Results highlight the important energy absorption role that floor coverings have during impacts on the hip. In conclusion, it is suggested that it would be cost-effective to install energy absorbing flooring in areas where there is high risk of fall-induced injuries.