Acceptability and compliance with wearing energy-shunting hip protectors: a 6-month prospective follow-up in a Finnish nursing home

Age and Ageing, March, 1998 by Jari Parkkari, Jussi Heikkila, Pekka Kannus

Introduction

Hip fractures are an important public health problem in economic terms [1, 2] and because of their association with high morbidity and disability, high risk for long-term institutionalization and increased risk of death in older people [3-8].

In the pathogenesis of the hip fractures, falling, the impact energy created by the fall and the energy-absorption capacity of trochanteric soft tissue are the main determinants of hip fracture [9-16], although bone mineral density also plays an independent role in the pathogenesis of this injury [16, 17]. Most hip fractures relate to a direct impact on the trochanteric area of the hip [9, 10, 13, 17]: approximately 25% of such falls cause hip fracture [18] while less than 2% of all falls lead to this injury [19, 20].

Thus, it seems reasonable to consider that a well-designed external hip protector could prevent some hip fractures, even in those older people in whom bone quality and propensity to fall would remain unaltered. A randomized study indicated that the use of external hip protectors could reduce the risk of hip fracture [18]. However, only 24% of the nursing home residents participating in this study wore hip protectors regularly [18].

A passive injury prevention strategy, such as an external hip joint protector, requires evidence on protector efficacy as well as evidence of acceptance and compliance of the device by potential users before any population-level benefit can be expected. The efficacy of an external hip protector in prevention of hip fractures has been provisionally shown in both biomechanical and clinical studies [18, 21, 22]; however, the acceptability and compliance in older subjects is not well studied.

Previous studies on hip protector compliance among elderly people have identified factors that relate to a positive attitude to wearing hip protectors. These include: female sex, living alone, having mobility problems, experiencing previous falls and injuries, perceived intrinsic cause of falls and dissatisfaction with social contacts [23, 24]. The most often mentioned protector-related factors indicating acceptability include: appearance, comfort, fit and efficacy, easy laundering and low cost [23, 25]. Cameron and Quine [25] reported that the main factors for compliance are perception of personal risk of fall and fracture and belief that the fracture is preventable. Also, awareness of the prevalence, causes and consequences of hip fracture might increase the motivation to buy and wear a hip protector, despite some extra effort and slight discomfort caused by protector usage [25].

A recent study gives preliminary evidence of the increased compliance if additional support is given when starting to wear an external hip joint protector [26].

The purpose of the present study was to investigate prospectively the acceptability and compliance for the use of an energy-shunting hip protector in institutionalized elderly people. Our research question was: what will the protector acceptability and compliance be if information and education is given to the nursing home caregivers only? This relatively low-effort approach was thought to approximate the real-life situation in nursing homes. The main outcome measures were the proportion of the residents who agreed to use the device, the number of hours of wearing the protector and the attitudes of the study subjects and the caregivers about the appearance, comfort, fit, efficacy and laundering of the protector.

Materials and methods

Study subjects

The voluntary ambulatory elderly subjects for this 6-month follow-up study were recruited from the Himminkoto nursing home, Lempaala, Finland. At the time of the study, the home had 57 elderly residents, 26 of whom were mobile and thus potential study subjects.

The caregivers of the nursing home were given an introductory talk, where they received information on hip fractures and a list of the risk factors for hip fracture. After this session, the authors did not influence the selection of the study subjects; the caregivers independently selected 19 people who they felt had a high risk for a fall and fracture of the hip. The caregivers regarded the remaining seven residents as having a low risk of falling because of their independent walking ability. The selected 19 residents all needed a walking aid.

The carers were then asked to list all residents to whom they offered the protector and to note reasons for negative responses. Also, during the 6-month follow-up, the possible interruptions in the use of the protector and the reasons for these were recorded. Wherever possible, any subject who stopped wearing the protectors was replaced by a same-gender, same-aged new resident. One of the authors (J.P.) determined the mental status of the study subjects, grading the status on 4-point scale (cognitively intact, mild dementia, moderate dementia and severe dementia) [27, 28] and recorded their medical conditions and medications.

KPH hip protector

The detailed description and the force attenuation capacity of the selected hip protector (Figure 1) has been reported in the previous biomechanical studies [22, 29, 30]. The protector was designed to cover the greater trochanter, to shunt the impact energy away from the greater trochanter to the soft tissues lying anterior, posterior and superior to the proximal femur and to absorb partially the fall-induced impact energy from the hip. The inferior contact of the protector was on the femoral shaft.