Effects of shear-thickening polymer on force attenuation capacities in hip protectors

Many elderly people use hip protectors to prevent hip fractures from sideways falls. These hip protectors absorb or shunt away the energy applied to the greater trochanter. Herein, shear-thickening polymer (STP)-based hip protectors composed of STP and polyurethane foam are studied. The purpose of this study was to identify the main factor that reduces the impact force directly applied to the femoral neck region and to determine the optimal thickness of STP in hip protectors. Seven hip protectors of different thicknesses were prepared, and two sets of free-fall mechanical tests with a low impact energy of 25.1 J and moderate impact energy of 44.1 J were conducted for each hip protector. When the thickness of STP exceeded 8 mm, the resultant peak force tended to plateau under both impact conditions, and the force attenuation capacity decreased even under low impact energy conditions. Thus, a hip protector with a 6 mm or 8 mm STP and 5 mm foam was recommended. The STP was the key factor affecting force attenuation capacity, not the polyurethane foam. However, the foam also played an important role in helping the STP function and improving compliance for users.

Hip Protectors for Community-Dwelling Older Adults

In community-dwelling older adults who wore hip protectors there was no difference in the risk of hip fractures or pelvic fractures, compared to those who did not wear hip protectors. Three guidelines were identified that include recommendations around the use of hip protectors in older adults. One guideline suggests that hip protectors should be considered in adults at risk for falls and hip fracture. One guideline conditionally recommends hip protectors for frail older adults in the appropriate environment. One guideline suggests that hip protectors should not be considered in older adults in community settings.

Hip Protectors and their Role in Hip Fracture Prevention: A Review

Hip fractures cause severe worldwide morbidity and loss of independence, costing national healthcare systems millions of pounds each year. The incidence is increasing with the expanding elderly population common of many Western countries. Hip protectors have been progressively studied in recent years focussing upon their use in hip fracture prevention, and compliance levels. This review aims to determine the effectiveness of protectors, and also investigates compliance levels. A search for English language Randomised Controlled Trials (RCTs) testing effectiveness of hip protectors was performed on Medline and Embase. Nine articles fulfilling the search criteria were found. Each was reviewed for hip protector effectiveness and compliance rates within the study, with results and conclusions critically-appraised. Of the nine articles, six (66.6%) found hip protectors to be effective in preventing hip fractures in selective populations. However, poor compliance rates were found in all reviewed trials. Future research should therefore focus upon improving compliance rates in the studied population.