Archives of Gerontology and Geriatrics 21 (1995) 179-189

ARCHIVES OF GERONTOLOGY AND GERIATRICS

Prevention of hip fractures in the elderly: receptivity to protective garments

Ann H. Myers *a, James D. Michelson b, Mark Van Natta c, Quentin Cox d, Riyaz Jinnah e

"Laboratory of Behavioral Sciences, National Institute on Aging, National Institutes of Health, Gerontology Research Center, 4940 Eastern Avenue, Baltimore, MD 21224, USA

bDepartment of Orthopaedic Surgery, School of Medicine, The Johns Hopkins University, The Johns Hopkins Outpatient Center,

601 N. Caroline Street, Baltimore, MD 21205, USA cCenter for Clinical Trials, The Johns Hopkins School of Hygiene and Public Health, The Johns

Hopkins University, 61$ North Wolfe Street, Baltimore, MD 21203, USA dDeparlmolt of Orthopaedics, Leicester University Hospital, Leceister, UK

eDepurtment of Orthopaedic Surgery, The Johns Hopkins University, Suite 204, 724 Maiden Choice Lane, Baltimore, MD 21228, USA

Received 6 February 1995; revision received 20 March 1995; accepted 22 March 1995

Abslract

A case study was undertaken to determine perceptions about protective garments for the prevention of recurrent hip fractures. We studied 169 patients with hip fractures, over 50 years of age, who were admitted to four university-afftliated hospitals. Proxy respondents were interviewed for 36% (n= 61) of the patients. Significant differences were found in the two groups; therefore, only the analyses from 108 patients who were interviewed are reported. Seventy percent of the patients were willing to wear a padded garment prescribed by a doctor. Factors associated with a positive response were no previous hip fracture, and an intrinsic cause of the fracture (P < 0.05). Over half (55%) of the patients were willing to wear an inflatable garment. Being female and fracturing the hip away from home were two factors that were associated with a positive response. Characteristics of the protective garment that patients thought were a concern or very important were effectiveness (83%), fit (82%), comfort (78%), laundering (66%), cost (57%), not showing (55%) and looked well (54%). These findings may assist investigators in the design of protective garments and thereby increase the recep- tivity and compliance among elderly patients.

* Corresponding author, Tel.: 410 558 8210; Fax: 410 558 8233.

SSD1 0167-4943(95)00637-Z

180 A.H. Myers et aL/Arch. GerontoL Geriatr. 21 (1995) 179-189

Keywords: Elderly; Energy-absorption; Hip fractures; Prevention; Protective garment; Recep- tivity

1. Introduction

The incidence of hip fractures is steadily increasing among elderly persons. By the year 2000 the number of hip fractures is expected to reach 300 000 (Brody et al., 1987). In North America and northern Europe, the age-specific rate of hip fractures begins to rise at about age 40 and doubles every 5-7 years, through to age 90. Given this exponential increase in the rate of hip fractures, in the report of Heithoff and Lohr (1990), the incidence of hip fractures might be reduced as much as 50% if the onset of this rise could be postponed by only 5 years. In addition, the overall reoc- currence rate for a second hip fracture is estimated to be 1% at 1 year, 8% at 5 years, 16% at 10 years and 29% at 20 years (Melton, 1982).

Most hip fractures are the result of the impact forces from a fall (Cummings and Nevitt, 1989). In a falling incident, the kinetic energy is converted into stress on the musculoskeletal system. An early classic work by DeHaven (1942), examined the biomechanics of falling and the effect of the landing surface. Investigators have con- tinued to address the mechanisms of hip fracture (Hayes et al., 1991; Lauritzen and Lund, 1990; Robinovtich et al., 1991) and the attenuation of the impact forces through the development of energy-absorbing materials (Hipp et al., 1991; Lauritzen and Askegaard, 1992; Wortberg, 1988). A passive, protective strategy would be pre- ferred to control or reduce such an injury (Haddon and Baker, 1989), but the use of energy-absorbing materials would require the active participation of an elderly person by wearing a protective undergarment. In a recent report of a clinical evalu- ation of hip protectors among nursing home residents, fractures occurred when residents fell and were not wearing the protectors (Lauritzen et al., 1993). Hip pro- tectors have been developed that are effective in preventing a fracture (Lauritzen et al., 1993); however, regularly wearing the protective garment remains an important issue. Reco~,nizing the importance of compliance, this case study was undertaken to explore receptivity to a protective garment and the importance of selected characteristics of the garment for compliance.

2. Materials and metlmds

A study of patients with hip fractures was undertaken to explore both the characteristics surrounding the hip fracture and elderly persons' perceptions about a protective garment. All patients, 50 years of age and older, with the diagnosis of a hip fracture, were admitted to four university-affiliated hospitals in Baltimore, from September 1988 through March 1990, were identified upon admission. Patients who had fallen in the hospital and fractured their hip were excluded. The patient or their proxy respondent was contacted and interviewed while the patient was in the hospital. The patient's medical record was reviewed and pre- and post-operative X- rays were read by two orthopaedic surgeons on the study team (JM, R J). Data collected from the interview, medical records and X-rays included: sociodemo-

A.H. Myers et ai . / Arch. Gerontoi. Geriatr. 21 (1995) 179-189 181

graphic, habitat, medical conditions, medications, history of falling and fractures, fear of falling, circumstances and environment surrounding the hip fracture, cogni- tive status, mobility, perceptions about the use of padded and inflatable protective garments, characteristics of the undergarment, type of fracture, surgical repair tech- nique, degree of displacement and comminution of the femur, length of hospital stay and discharge disposition.

Perceptions were elicited in four areas with the following order of questions. The patient was asked these questions near the end of an hour-long interview and without being shown a garment or picture of one.

(1) Do you think wearing a special garment could protect you from another frac- ture if you fell?

(2) If we were designing a garment you could wear which could prevent a fracture should you fall, how important are the following factors: cost, laundering, fit well, didn't show, looked well, comfort in summer and winter, was effective7

(3) If there were a garment, say a pair of underpants with padding, that you could wear to prevent another fracture should you fall, do you think you would be willing to wear them if your doctor prescribed them?

(4) If there were a protective garment that inflates like a cushion when a person fell, would you be willing to wear it to prevent a fracture?

Mental status was ascertained using the standardized mini Mental Status Exam (Folstein et al., 1975), which has a range of 0-30. Scores of 17 or less were categoriz- ed as severe dementia; 18-24 as moderate dementia; and 25-30 as being cognitively intact.

Difficulty with functional mobility was elicited by asking about three tasks: get- ting out of bed, getting out of a chair and walking. Difficulty in mobility was quan- rifled as no difficulty, or having difficulty in one, two or all three tasks.

The perceived cause of the fall was categorized as intrinsic, extrinsic or other fac- tors (Droller, 1955). Intrinsic factors included, dizziness, light-headedness, loss of balance, legs gave way and weakness. Extrinsic factors included, tripped, stumbled, slipped, slid off surface and pushed.

Respondents were asked about the presence of the most common chronic medical conditions in the elderly (Collins, 1988), and the most frequent acute medical condi- tions: heart disease, cancer and stroke. A medication history was also elicited for these conditions as well as for any sleep or psychotropic medications.

Associations between garment-related responses and other covariates were assess- ed using the x 2 statistic. Continuous variables, such as age and mini-mental status, were categorized. Due to the exploratory nature of the study, P-values are con- sidered descriptive statistics and therefore were not adjusted for multiple com- parisons. The correlations between garment characteristics were determined using Spearman's correlation coefficient statistic (Kendall, 1955). Analyses were perform- ed using SAS (1985).

3. Re~lts

Thirty-six percent (n = 61) of the 169 patients required proxy respondents. Com- parison of patients and proxy respondents versus self-reporting patients revealed sig-

182 A.H. Myers et al. / Arch. Gerontol. Geriatr. 21 (1995) 179-189

Table I Study population characteristics by respondent status

Characteristic Self Proxy Total P value (n = 108) (n = 61) (n = 169)

Soe~lmqCm~ Median age (yrs) 76 85 80 <0.001 Male sex 40% 41% 40% 0.882 Income ~: $5000/yr 570/0 57% 570A 0.988 Education ~e high school 38% 30% 35% 0.328 Lives in multi-story house 520A 49% 51% 0.739 Lives alone 35% 18% 29% 0.018

iatervtew Median length of interview

(rain) 62 63 63 0.367

lVldkal ~ t e ~ Falls last 3 months 22% 43% 30% 0.005 Previous fracture 45% 270/0 39% 0.025 Previous hip fracture 7% 16% 1 i% 0.069

PlffMeal/mm~ dmraeteri/les Mobility:

Normal 560/0 33% 470/o Mild difficulty 26% 39% 31% Severe difficulty 18% 28% 22%

Mental status: Cognitively intact 35% 0%0 30% Mild dementia 50% 35% 48% Severe dementia 15% 65% 22% Missing (n) 5 44 49

0.017

<0.001

~ eea41tiom Arthritis 51% 53% 50% 0.817 Hypertension 37% 43% 39% 0.450 Cataracts 33% 46%0 36% 0.113 Heart diw, ase 260/0 420/0 31% 0.034 Stroke 16o/o 29O/o 200/o 0.042 Cancer 19% 20e 190/0 0.837 Myocardial infarction i I% 120/o 12°/o 0.886 Osteoporosis 8% 17% 10% 0.092 Diabet~ raellitus 8% 10% 9% 0.745 Glaucoma 4% 11% 6% 0.087 Parkinson's disease 5% 5% 5% 0.948

P t ~ k a l emtremteat Type of footwear:

Shoes with heel 49% 53% 51% Shoes with no heel 35% 16% 28% No shoes 16% 31% 21% Unknown (n) 13 10 23

Site of lea Outdoors 34% 3% 23% Bedroom 14% 32% 21% Living/dining room 17% 17% 17%

0.017

A.H. Myers et al. / Arch. Gerontoi. Geriatr. 21 (1995) 179-189

Table 1 (Continued)

183

Characteristic Self Proxy Total P value (n = 108) (n = 61) (n = 169)

Kitchen 140"6 150"6 140/0 Bathroom 7% 8°'6 8% Stairs 6% 3% 5% Other 70/0 20o/0 12°/o

Tim of~y Daylight (8:01 am-4:00 pro) 53% 45% 50% Dusk (4:01 pm-8:00 pro) 34% 40°'6 36% Night (8:01 pm-8:00 am) 13% 16°/o 14% Unknown (n) 5 3 8 Adequate lighting 91% 94% 92% Normally wears glasses 64% 59% 62% Wearing glasses at time of fall 45% 470~6 46%

Biemedta~al faete~ Hard landing surfacc 71% 67°'6 70% Landed on fractured hip 72% 570/0 68%

Aetiviff at time ef fall Walking 53% 54% 54% Standing 160/0 90/0 140/0 Other 30°,6 36% 32%

P ~ came of blp fracture Extrinsic a 65% 540/0 620A Intrinsic b 35% 46% 38% Missing (n) 16 20 36

Type of f raca~ Intertr~hanteric 50% 48% 49% lntracapsular 34% 43% 370"6 Subtrochanteric 16% 10% 14%

Medkatlem l~chotropic agents:

Nerve/slceping 19% 23% 21% Alcohol 24 h before fall 9°'6 2% 70"6

Sm]lkal treatlteat Open reduction, internal 70% 48% 62%

f'mafion Endoprustbetic hip 28% 49% 36%

replacement Non-operative treatment 2% 3% 2%

<0.001

0.577

0.524 0.539 0.886

0.538 0.104

0.394

0.206

0.411

0.589 0.066

0.015

Mem~ Died before discharge 2% 11% 5% 0.007

aTripped, stumbled, slipped, pushed, missed seat, slid off surface, bumped into object, furniture broke. bLegs gave way, dizzy, light-headed, weakness, passed out, lost balance, paralysed.

184 A.H. Myers et al./Arch. Gerontol. Geriatr. 21 (1995) 179-189

nificant differences in the following variables: median age, 85 years vs. 76 years; living alone, 18% vs. 35%; outside location of fall, 3% vs. 33%; difficulty with mobil- ity, 67% vs. 44%; median mini-mental score, 13 vs. 23; and no shoes at time of frac- ture, 31% vs. 16%, respectively (P < 0.05). Analyses comparing self-reporting patients and proxy respondents revealed significant differences in response to all gar- ment questions (P < 0.05). The responses of the combined group (n = 169) revealed a greater proportion of 'don't know' responses, whereas in the self-reporting patient group (n = 108) there was an increased proportion reporting 'a concern'. Therefore, we did not combine the two groups and report here only the results of the 108 self- reporting patients.

Table 1 reveals that a majority of the study population were female (60%), had less than a high school education (62°/0), an income less than $5000 per year (57%), were community-dwelling (94%), and did not live alone (65%). As anticipated, arth- ritis and hypertension were the most prevalent chronic conditions reported (51% and 37%, respectively). Seven percent had experienced a previous hip fracture, and 44% had some difficulty with mobility.

Most fractures occurred indoors (66°/0), during daylight (53%) and with perceived adequate lighting (91%); however, a majority (55%) were not wearing glasses at the time. Most subjects were walking or standing at the time (69°/0), reported landing on a hard surface (71%) and landing on the fractured hip (72%). The most frequently reported extrinsic cause of the fall was slipping (20%), the most frequent intrinsic cause was 'legs gave out' (12%).

Table 2 Preceptions about protective garments

Questions a No Yes Don't know Unknown (%) (%) (%) (%)

About me of gmment Do you think garment could 25.0 33.3 38.0 3.7

protect Would you wear if prescribed 14.8 70.4 10.2 4.6 Would you wear inflatable 20.4 54.6 19.4 5.6

cushion

About garment Not A concern Very Don't d m ' ~ m t i ~ " important (%) important know (%)

(%) (%)

Unknown (%)

How important are: Cost 29.6 36.1 21.3 11.1 1.9 Laundering 22.2 50.9 15.7 8.3 2.8 Comfort in winter and 7.4 61,1 16.7 12.0 2.8 summer

Fit well 4.6 62,0 20.4 10.2 2.8 Didn't show 31.5 41.7 13.9 9.3 3.7 Looked well 30.6 40.7 13.9 11.1 3.7 Was effective 3.7 38.0 45.4 9.3 3.7

an = 108

A.H. Myers et ai. / Arch. Gerontoi. Geriatr. 21 (1995) 179-189 185

The responses from proxy respondents were not combined with the data from self- reporting patients to reduce bias in the results. The subjective nature of the study questions necessitated patients' personal responses. Proxy respondents, however, have been shown to reliably report more objective data such as demographic factors (Magaziner et al., 1988). Table 2 indicates that 38% of respondents did not know if a garment would protect against a hip fracture in case of a fall; however, 70°,6 replied that they would be willing to wear a padded protective garment if prescribed by their doctor. Fifty-five percent indicated their willingness to wear an inflatable cushion. The characteristic that was most important about the protective garment was its effectiveness. There was a concern, most frequently, about the comfort and fit of the garment and laundering. The factors that were less frequently important were cost and those of an aesthetic nature - - that the garment did not show and looked good.

Covariates that were associated with wearing protective garments are provided in Table 3 (P < 0.05). Those who were more likely to think a garment could protect did not sustain the fracture at home (RO = 7.4; P = 0.007) and fell on their sides (RO = 3.7; P = 0.029). Those persons who reported they would wear a protective garment if prescribed by their physician did not report a history of a previous hip fracture, and perceived an intrinsic reason for the fall preceding the fracture. Those

Table 3 Factors matooiated with preceptious about protective garments

No (n) Yes (n) RO 'yes' P value

De ym ahhk i~m~t ce~l l m ~ . Place of fracture:

Home 24 21 Other than home 2 13

Dkcgt~t of fall: Forward/backward 11 6 Sideways 13 26

Wmld yam wear ff iwucdlm~. Perc~ved cause of fall:

Intrinsic 0 19 Extrinsic 9 32

Previous hip fracture: No 12 83 Yes 4 4

7.4 0.007

3.7 0.029

11.4 0.027

6.9 0.005

Gender: Female 10 55 2.6 0.044 Male 12 25

Place of fracture: Home 20 53 Other than home 1 23 8.7 0.017

186 A.H. Myers et al./ Arch. Gerontol. Geriatr. 21 (1995) 179-189

who would consider an inflatable garment were likely to be female (RO = 2.6; P = 0.044), and who did not sustain the fracture at home (RO = 8.7; P = 0.017). Fe- males were 4 times as likely as males to report that laundering was a concern or very important (P = 0.002).

The correlation of responses between the garment characteristics was examined and revealed: how the garment looked and that it not show were highly correlated (r = 0.90); the garment fit and comfort were also highly correlated (r = 0.79). A moderate correlation (r = 0.49) was found between garment comfort and laundry. The effectiveness of the garment, which was most frequently reported to be very im- portant, was not correlated with any of the other characteristics.

The pattern of responses across the following three questions was examined: do you think a garment could protect?; would you wear a padded garment if prescrib- ed?; would you wear an inflatable garffment? Ten percent of the patients' responses were 'didn't know' or 'unknown' to all three questions. The largest proportion (28%) responded positively to all three questions. There did not appear to be a tendency to answer all 'yes' or all 'no' in responding to the questions.

4. Disemsion

This study explored elderly persons' perceptions about taking protective action to prevent a serious injury from reoccurring. At least one-third of the respondents did not know if a garment could protect them from another fracture. In addition, 25% did not think it could. This may suggest the need for information on how a hip frac- ture generally occurs. Even though all but one or two patients in this study ex- perienced the impact of a fall, it may not be clear to the patients that the impact was most likely the cause of the fracture. There seems to be a common hypothesis among lay persons, and even some health professionals, that a person's hip fractures first and then the person falls. This belief could explain why an elderly person would not know that a fracture might be prevented by protective wear. This belief can retard preventive strategies from being developed and used. In this study we also examined the hypothesis that the fall caused the fracture by asking several questions about pro- dromal symptoms and circumstances surrounding the fracture. We found only two patients who reported having sudden hip pain before falling. A small percentage of fractures occur with minimal stress to the bone and in patients who have received steroids, radiation to the pelvic area and certain bone diseases. Only two occurred with movement that placed torque on the hip. Most hip fractures are the result of impact forces, indicating that energy-attenuation is a very relevant preventive strategy.

Seventy percent of the patients in this study indicated they would wear a padded protective garment if prescribed by their physician. In other areas of injury control and protective behavior, such as seat-belt use, only 33% of elderly persons wear their safety belts regularly, the lowest proportion of any age group (Thornberry et al., 1986). However, there is some evidence that adult patients frequently heed physi- cians' advice about safety belts (Logsdon et al., 1989); they reported that patients who received safety belt counselling were 3.6 times more likely to use them a year

,4.tt. Myers et al./Arch. Gerontol. Geriatr. 21 (1995) 179-189 187

later. This study examined perceptions during the post-operative hospitalization period. It would be important to know if the perceptions persisted after discharge from the hospital and how these intentions correlate with subsequent use.

Over half of the patients responded positively to an inflatable protective garment. Patients may understand the concept from the use of airbags in automobiles. The application of airbag technology to the prevention of hip fractures had been sug- gested by Clark (1984). While the technical feasibility has been examined (Clark, 1984), the devices for laboratory testing and clinical evaluation are still in the developmental phases (Charpentier, 1994).

One of the next steps in developing the garment and examining compliance would be to show patients examples of garments, have them try them on and see it they can manage self-care activities. For instance, a certain type of garment may be easier for an elderly community-dwelling person with arthritis in the hands to use in- dependently. The elderly can provide valuable information if their co-operation is sought. It is important that information about preferences be obtained from focus groups' interviews and the direct involvement of potential consumers in the design process (Fozard, 1994). Long-term use will be necessary if hip fractures are to be prevented. Wallace et al. (1993) have been studying ways to enhance compliance and report using a period of time (usually a week) to familiarise nursing home residents with padded underwear prior to participation in a research protocol.

As has been noted above, physician advice has been shown to have an impact on elderly persons' behavior. Geriatricans, primary care physicians and providers are encouraged to take an active role in injury prevention, since hip fractures among the elderly are reaching epidemic proportions (Lowenstein and Hunt, 1990; Rockwood et al., 1990). Studies that address physician-patient communication about the need for and potential benefits from wearing the protective garment/device would be useful. Messages can be designed and evaluated in relation to compliance and outcomes.

It is equally important to understand what factors and characteristics are related to negative responses. Surveys indicate that the most frequently reported reasons for not wearing a seat belt were physical discomfort, followed by fear of entrapment, travelling only a short distance and too much trouble (Kenchenmeister and Yanik, 1978; Mawson and Biundo, 1985; Newport and Tarrance, 1981). The personal response system is another example of a technological device worn by the elderly that can summon help should a person fall or some other emergency arise. The system is comprised of a small electronic device that is worn and can alert, when ac- tivated, a facility that in turn provides personal assistance (Dibner, 1991). When this device was first introduced and evaluated among the elderly, 65% of a frail, elderly, urban sample accepted the service when offered. The most common reasons for re- jection included: afraid or distrustful of a mechanical device, afraid of cost, afraid or distrustful of the agency offering the service and confusion about how the system operated (Dibner et al., 1982). Understanding more fully the reasons for not wanting tO wear a protective garment can help researchers and clinicians with compliance issues.

188 A.H, Myers et al , / Arch. Gerontol. Geriatr. 21 (1995) 179-189

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