Risks of subsequent contralateral fractures of the trochanteric region in elderly

Abstract

Background:

Fractures in elderly are always a dramatic event and the healing is often not complete. In a context of bone fragility, repeated fractures are a growing problem in the industrialized world, in which the mean age of population is increasing. The aim of this study was to identify those general factors which may increase the risk of subsequent trochanteric fractures after an initial lesion.

Materials and methods:

Three-hundred and thirty-one patients who underwent intramedullary fixation for trochanteric fractures between January 2012 and December 2013 were studied. Forty subjects yet alive (group 1), affected by a subsequent contralateral hip fracture, were compared with 202 patients (group 2) affected by isolated trochanteric fracture. Days of hospitalization before surgery, hospitalization, period of rehabilitation, type of discharge and comorbidities, that are reported in literature as possible risk factors for hip refracture, were analyzed. In addition, all patients were interviewed in order to assess if a therapy for osteoporosis was prescribed after the initial fracture and how their gait had been modified by fractures.

Results:

Days of hospitalization before surgery, hospitalization, period of rehabilitation and type of discharge were not predictive factors for subsequent fractures, as well as diabetes mellitus, hypertension and cardiac diseases. The presence of neurologic and respiratory diseases were associated to a higher risk of refractures, as well as the absence of specific medical treatment for osteoporosis.

Conclusions:

Neurologic and respiratory comorbidities and the absence of osteoporosis medical treatment are the variables associated to a higher risk of contralateral fractures. Physicians can do more in terms of prevention and strategies must consider these risk factors. (www.actabiomedica.it)

Introduction

Osteoporosis is a systemic skeletal disease characterized by low bone mass and microarchitecture deterioration of bone tissue, with a consequent increase in fragility and susceptibility to fracture (1). Fractures of the proximal femur in elderly are always a dramatic event and the physical and psychological healing is often not complete.

Hip fractures are an important cause of death and disability among elderly (2, 3), who are characterized by decreased quality of life (4, 5) as well as walking restrictions, difficulty in climbing stairs and problems in self-care. In a context of bone fragility, refractures are a growing problem in the industrialized world, in which the aging population is constantly increasing (6). Patients who have suffered hip fracture have an increased risk of subsequent fracture of the contralateral hip (second hip fracture) (7). The one-year risk of this complication varies from approximately 2% to 10% (8, 9). The lifetime risk of a second hip fracture has been estimated at 20% but may be as high as 55% (10). A second fracture necessitates further surgery and hospital care and may result in additional disability or death.

Given these clinical risks among individuals, as well as the economic costs related, it seems important to identity those subjects at greater risk for a second fracture so that they can be targeted for fracture prevention interventions.

Risk factors for first hip fracture have been well studied (11, 12) and may be divided as consequent to alteration of bone quality/integrity or falls.

Relatively less known are risks and protective factors for hip refracture. These may be categorized as related to specific bone quality disorders (e.g. type and grade of osteoporosis) or to more general conditions (demographic, clinic and therapeutic).

The aim of this study was to identify these general factors which may increase the possibility of a subsequent contralateral hip fracture.

Methods

Three hundred thirty-one patients, older than seventy years of age, underwent intramedullary fixation for fractures in the trochanteric region between January 2012 and December 2013 at the University Hospital of Parma.

Data acquisition were extracted from medical records of the hospital.

Eighty-nine subjects were excluded: 31 died within a year of the trauma, 40 were unable to walk before surgery and were not admitted to the rehabilitation program and in 18 was not possible to obtain the consent for the management of the personal data.

Forty patients (group 1) out of 242 available for the study, and all characterized by a sufficient preoperative walking ability, had another contralateral hip fracture. This first group was compared with 202 patients (group 2) affected by isolated femoral fracture.

It was assumed that all fractures in this study were the result of banal falls; pathological metastatic fractures and high-impact injuries (traffic accident or falls from more than sitting height) were not included.

In all cases age, gender, body mass index (BMI), days of hospitalization before surgery, hospitalization, period of rehabilitation, type of discharge (at home or in a rehabilitative institute) and comorbidities, that in literature (3) are reported as possible risk factors for subsequent fractures, were collected.

The latter included neurologic pathologies (cognitive impairment and dementia), diabetes mellitus, hypertension, cardiac diseases (myocardial infarction, angina pectoris, cardiac insufficiency, arrhythmia) and respiratory diseases [chronic obstructive pulmonary diseases (COPD) comprising chronic bronchitis and emphysema, asthma, interstitial pneumonia, chronic respiratory insufficiency].

In addition, these patients were interviewed by phone in order to assess if a specific therapy for osteoporosis was prescribed after the initial fracture and how their gait pattern had been modified after surgery. In particular, it was asked to describe how much the walking skills worsened after the trochanteric fracture of the femur in both groups and subsequent fracture in group 1.

These changes were quantified as follows:

• - unchanged: if the fracture did not result in any change in the walking ability

• - slightly reduced: if the ability to walk remained valid but limited

• - reduced: if this ability was possible with the help of orthopaedics devices such as crutches

• - greatly reduced: if after the fracture the patient could walk only with the help of another person.

Statistical analysis

Results were statistically analyzed using the SPSS Statistics software (version 20.0).

Quantitative variables (age, BMI, period of rehabilitation and hospitalization) were compared between groups by a two-tailed unpaired t-test. Differences in the categorical variables (gender and type of discharge) were compared using the chi-squared test. The relation between the fracture and comorbidities was evaluated by the chi-squared test in a univariate analysis.

Furthermore, responses to phone interviews were analyzed using the chi-squared test. The differences were considered significant when p value was less than 0.05.

Results

Age, gender and BMI of group 1 and 2 are reported in table 1.

Table 1.

General characteristics of the two groups of patients

	Group 1	Group 2	p value
Women (n. 202)	34	168	>0.05
Men (n. 40)	6	34
Mean age (years)	84 (range: 70-99)	83.7 (range: 70-97)	>0.05
BMI	26.4 (range: 22.4-28.4)	26.6 (range: 23-28.2)	>0.05

Risk factor

The analysis of risk factors is illustrated in table 2 and 3. In particular days of hospitalization before surgery, hospitalization, period of rehabilitation, type of discharge and concomitant diabetes mellitus, hypertension and cardiac diseases were not predictive factors for subsequent fractures. Significant differences between the two groups regarding neurologic and respiratory diseases were observed. These 2 risk factors were more frequent in group 1.

Table 2.

Days before surgical procedure, hospitalization, period of rehabilitation and type of discharge in group 1 and 2

	Group 1	Group 2	p value
Days before surgery (average)	2.9 (range 1 – 9)	3 (range 1- 7)	0.482
Hospitalization (days/average)	15.1 (range 7 – 35)	15 range (7 – 34)	0.593
Period of rehabilitation (days/average)	41.2 (range 35 – 50)	40.5 (range 36 – 48)	0.210
Type of discharge	at home: 6 to a rehabilitative institute: 34	at home: 34 to a rehabilitative institute: 168	0.607

Table 3.

Comorbidities in group 1 and 2

	Group 1	Group 2	p values
Neurologic pathologies (cognitive impairment/dementia)	21/40 (52.5%)	60/202 (29.7%)	<0.05
Diabetes Mellitus	5/40 (12.5%)	25/202 (12.4%)	>0.05
Hypertension	19/40 (47.5%)	97/202 (48%)	>0.05
Cardiac diseases	12/40 (30%)	65/202 (32%)	>0.05
Respiratory diseases	13/40 (32.5%)	23/202 (11.4%)	<0.05

Results of telephone interviews

In group 1 only seven patients had a specific therapy with bisphosphonate after the initial fracture, which was suspended in 2 cases after less than three months of treatment for side effects, and 1 received therapy with Vitamin D and Calcium (table 4).

Table 4.

Specific osteoporosis medical therapy in group 1 and 2

	Group 1	Group 2	p values
Specific osteoporosis therapy	8/40 (20%)	91/202 (45%)	<0.05

In group 2 sixty subjects underwent a therapy with bisphosphonate and 31 had an empiric treatment with Vitamin D and Calcium (table 4).

Regarding gait patterns after a trochanteric fracture, the results of both groups are summarized in table 5. The analysis of these parameters did not show differences between group 1 and 2 (Chi Square = 0.2559, p = 0.8799).

Table 5.

Gait pattern after trochanteric fracture in group 1 and 2

Gait	Group 1	Group 2	Total
Unchanged	2	10	12
Slightly reduced	23	110	133
Reduced	7	41	48
Greatly reduced	8	41	49
Total	40	202	242

The significant worsening of quality of gait of patients of group 1 after trochanteric fracture and following a contralateral subsequent femoral fracture is illustrated in table 6 (Chi Square = 9.983, p = 0.006797).

Table 6.

Gait patterns after trochanteric fracture and subsequent contralateral femoral fracture in group 1

Gait	After trochanteric fracture	After subsequent contralateral femoral fracture
Unchanged	2	0
Slightly reduced	23	3
Reduced	7	10
Greatly reduced	8	27
Total	40	40

Discussion

Aging is associated with a progressive loss of bone-muscle mass and strength as well as of hormone production. This decline in mass and strength associated with concomitant diseases typical of the geriatric status (13) increases the risk of fall and consequent fragility fractures (14).

Among these, hip fractures are accompanied by a high disability and mortality rate. These complications are more frequent in those subjects who undergo to a subsequent contralateral injuries, as well demonstrated by results regarding the gait pattern of this study (7, 15, 16).

For these reasons these traumatic events represent an important problem in elderly and the identification of the modifiable risk factors and an adequate therapy become a research priority in Ortho-Geriatric Medicine in order to prevent first lesion and its possible recurrence (17).

Nevertheless, preventing initial hip fractures by treating osteoporosis and avoiding falls by the elderly living in the community is not easy. Many specialized physicians (including rheumatologists, orthopaedics, rehabilitators, geriatrics, gynaecologist and endocrinologist) and generalists (internal medicine practitioners) are involved in the management of patients who sustain fractures. These providers have different priorities and connectivity in the care process is often lacking (18).

As consequence, authors believe that it could be easier to prevent the second hip fracture, especially for an orthopedic surgeon who tends to overlook the importance of proper diagnosis and preventive therapy focusing in the healing of the “fracture” and not of the “patient” as a whole.

In this study, 40 out 242 subjects (16.5%) underwent a second contralateral trochanteric fracture. This rate is higher than the incidence of past retrospective studies (5.4-11.3%) (7, 8), probably because in this case series all patients were older than 70 years of age.

The observational period was of 3 years after trauma because, as reported in the literature, the refracture occurs within this time in 85.7% of the cases (7, 18-20).

It has previously been reported that age and female gender were important risk factors for hip fracture and recurrences (21, 22). However, some reports have indicated that there are no differences in age or gender between unilateral and second hip fractures (7, 8). In the present study an influence of age and gender on second hip fractures was not possible to find because group 1 and 2 were similar for these two parameters.

Fragility fractures may also be linked to BMI. This variable has a negative correlation with hip fracture, and some authors (18-20, 23) have reported that a second hip fracture is related to a lower BMI. In the present study it was not possible to demonstrate a relation between BMI and second fracture because this parameter was similar in both group.

Days before surgery and rehabilitation period were not statistically different between the groups in this study as previously observed in other reports (2, 7, 9). In the University Hospital of Parma rehabilitation following trochanteric fractures is offered in the same way in all collaborative patients regarding walking ability. The rehabilitation program is always administered by a physiotherapist, started the day after the surgical procedure and continues at home or in a rehabilitation ward at least for 25-30 days.

In this study, it was initially hypothesized that discharge to a rehabilitative institute could diminish the possibility of a second fracture, but a statistically significant difference was not found. This was probably the consequence of the same rehabilitation protocol that was applied in both type of discharge. Furthermore, the admission of the patients in these dedicated structures is decided by specialized physicians who analyse in each subject several variables including architectural barriers in their apartments (presence of stairs and elevator and rooms distribution and measures), family dynamics and physical and psychiatric functions.

Regarding comorbidities, in this report cognitive impairment/dementia and respiratory diseases were important risk factors for trochanteric refractures. In the literature some authors confirm this result (7, 18-20) but others did not demonstrate this relation. However, neurologic problems decrease quality of life as well as walking ability and capacity of climbing stairs, thus facilitating the risk of recurrent falls.

In the same way, patients affected by impaired respiratory function have these problems with higher risk of subsequent fractures.

Furthermore, in subjects with chronic obstructive pulmonary disease the progression of osteoporosis has been demonstrated (24), thus worsening bone resistance and increasing its fragility.

For these reasons, when elderly patients have neurologic or respiratory disease, they should be carefully monitored and managed. The basic strategy for preventing a second trauma should be the fitting of hip protectors (25) and modifications to the home. For an elderly person with a respiratory disease, improving activity by pulmonary rehabilitation and aerobic exercises are recommended.

In addition, administration of osteoporosis medication should be considered as a preventive strategy.

Many studies examined the effects of different types of pharmacotherapy on the risk of subsequent fracture (2, 3, 26). When compared with no treatment or placebo, all pharmacologic interventions examined showed evidence of a protective effect for subsequent fracture, even relatively low doses of calcium and vitamin D (2, 3, 26, 18-20).

Unfortunately, it is well documented that osteoporosis itself is undertreated among patients in general, including individuals post hip fracture (27-29), and, among patients who do receive treatment, many have difficulty continuing with treatment on a long-term basis (18,19).

The findings of this study confirm that osteoporosis medications have a protective effect on fragility fractures. Authors underline the importance of treating osteoporosis and suggest that individuals post hip fracture who cannot tolerate, or have contraindications for certain medications (e.g. bisphosphonates, high-dose vitamin D) be encouraged to try others (e.g. lower dose vitamin D, calcium).

The present study was limited fragility by the small number of cases. However, its population was similar to other reports of the literature as well as the results obtained. For these reasons authors consider this case series valid and reliable.

It is therefore evident how the diagnostic-therapeutic management of fractures of the proximal femur is not simple, and it requires a multi-disciplinary approach including orthopaedic surgeon, geriatrics and physicians specialized in rehabilitation, as well demonstrated in several pathologies (30-33).

Conclusion

Fragility fractures of the trochanter region are a complex and multidisciplinary disease affecting elderly. Subsequent contralateral hip fractures are not infrequent and may be a devastating event for the patient. Neurologic and respiratory diseases, as well as the absence of osteoporosis medical therapy, are associated to a greater risk of contralateral refractures. Prevention strategies have to improve and they must take in consideration these observations.