Article, Geriatrics

Is there such a thing as a mechanical fall?

a b s t r a c t

Objectives: The term mechanical falls is commonly used in the emergency department (ED), yet its definition and clinical implications are not established. It may be used to attribute falls to extrinsic factors in the environment exonerating clinicians from conducting a thorough assessment of the fall’s underlying intrinsic causes. We con- ducted this study to determine how clinicians assess “mechanical” and “nonmechanical” falls; we explored con- ditions, fall evaluation, and outcomes associated with these diagnoses.

Methods: This study was a secondary analysis of a retrospective study at 1 urban ED. Data were obtained from medical records of patients aged 65 years and older who presented to the ED for a fall. We compared the associ- ated conditions/causes, the ED fall evaluation, mortality, ED revisits, subsequent hospitalizations, and recurrent falls between the 2 terms.

Results: We had a sample size of 350 patients: 218 (62.3%) with “mechanical falls” and 132 (37.7%) with nonme- chanical falls. There was little difference among associated conditions between the 2 fall labels other than me- chanical falls had more associated environmental causes but fewer syncope causes. However, more than a quarter of nonmechanical falls had associated Environmental factors as well. Similarly, there was little difference in the fall evaluation, ED revisit rates, recurrent falls, subsequent hospitalizations, and death between the 2 groups.

Conclusions: The term mechanical fall is unclear, inconsistently used, and not associated with a discrete fall eval- uation and does not predict outcomes. We propose eliminating the term because it inaccurately implies that a benign etiology for an older person’s fall exists.

Introduction

The term mechanical falls has become commonly used in emergency departments (EDs), yet its definition and clinical implications have not been established. It may be used to attribute falls to extrinsic factors in the environment and excuse clinicians from conducting a thorough as- sessment of underlying intrinsic causes in the patient. Given that a third of older adults in the United States fall annually and 2.3 million nonfatal falls were treated in EDs in 2010 [1],a figure that is likely to increase as the elderly population grows [2], it is important to understand what is often termed mechanical falls in the ED.

? Funded by the Hartford Foundation’s Center of Excellence.

* Corresponding author at: Emergency Department, Vajira Hospital, Navamindradhiraj University, 681 Samsen Road, Dusit District, Bangkok, Thailand, 10300. Tel.: +66 896840010.

E-mail addresses: [email protected] (J. Sri-on), [email protected]

(G.P. Tirrell), [email protected] (L.A. Lipsitz), [email protected] (S.W. Liu).

¹ Please contact: [email protected] with any questions or concerns.

The term mechanical fall is not well defined in academic research, and it is open to interpretation what differentiates a mechanical from a nonmechanical fall [3,4]. The term implies that an external mechanical force or object caused the fall. Although more than 25% of community- dwelling older adults have falls related to slipping, tripping, or stum- bling [5,6], external factors are seldom the sole cause of an elderly patient’s fall. In almost all cases, patients’ comorbidities and health sta- tus are involved: a younger person in the same environment probably would not have fallen. Because elderly fall patients are at high risk for recurrent falls [7,8], evaluation of fall patients should determine modifi- able fall risk factors. We hypothesized that the use of the term mechan- ical fall may lead to a less thorough evaluation of the elderly fall and may not adequately assess elderly fall etiology.

We conducted this secondary analysis of a retrospective study to determine what ED clinicians do to assess what they call “mechanical” and “nonmechanical” falls; we explored what conditions or pathologies ED clinicians attribute to these labels, whether the labels led to a specific fall evaluation approach, and what outcomes are associated with these diagnoses.

http://dx.doi.org/10.1016/j.ajem.2015.12.009

Methods

J. Sri-on et al. / American Journal of Emergency Medicine 34 (2016) 582-585

2.5. Data analysis

583

Study setting

This “mechanical fall” study was a secondary analysis of a retrospec- tive study that described the evaluation of ED fall patients presenting to 1 urban, level 1 trauma center, academic hospital ED [9].

Study population

We included patients aged 65 years and older who presented to the ED for a fall from January 1, 2012, through December 31, 2012, who had been assigned an International Classification of Diseases, Ninth Revision, “E” code of a fall (E880-E886 and E888) and had visited a primary care physician affiliated within the hospital’s network in the past 3 years. We excluded patients who were transferred from other hospitals to re- duce the potential of missing study data.

Data collection

We adapted our data collection form from the recommendations of the American Geriatrics Society/British Geriatrics Society Clinical Prac- tice Guideline for Prevention of Falls in Older Persons 2010 [10] and the Geriatric EMergency Department (GED) Guideline [11]. Details of the adaption have been described elsewhere [9].

One emergency physician and 1 research assistant performed the data abstraction. We met once a week to clarify terms and discuss the progression of data collection. The study’s principal investigator (SL) su- pervised data collection and monitored the quality of data abstraction. We randomly sampled 5% of 350 patient’s charts to test for Interrater agreement using Cohen ? coefficient.

There is no standard definition for what constitutes a “mechanical

fall.” “Mechanical fall” is a subjective term which is often associated with a slip or trip leading to a fall. We did not define “mechanical fall” ourselves; rather, we recorded the number of falls which were described as a “mechanical fall” by clinicians (ED residents and/or ED at- tending) in the patients’ electronic charts.

Outcomes

We first examined conditions/factors associated with mechanical vs nonmechanical falls. The categories for conditions associated with the

We compared differences in associated conditions/factors of the fall, evaluation, and follow-up events between mechanical- and nonmechanical-labeled patients. Proportions were presented for cate- gorical data and compared using ?² or Fisher exact test. Continuous data were presented as means with SDs if normally distributed and me- dians with interquartile ranges (IQRs) if nonnormally distributed; a t test was used to compare data if normally distributed and Wilcoxon rank sum test was used for nonnormal data. We analyzed all data using STATA software (version 13.0).

Results

A total of 450 patients were eligible for inclusion in this study. One hundred were excluded: 40 because they were improperly assigned an International Classification of Diseases, Ninth Revision, code; 29 be- cause they were transferred from other hospitals; 22 because they revisited for the same fall; 8 because they were duplicate charts; and 1 because the chart was inaccessible due to legal reasons. Our final analy- sis was based on 350 patients. In terms of reliability of chart review, the ? value was 0.84 (95% confidence interval, 0.67-1.00).

Two hundred eighteen patients (62.3%) had what was described as a mechanical fall, and 132 patients (37.7%) had nonmechanical falls. Me- chanical and nonmechanical falls were similar in terms of age, sex, race/ ethnicity, primary insurance, residence, and Charlson Comorbidity Index score (Table 1).

Overall, there was no clear discrete difference in the associated con- ditions between the 2 fall labels other than mechanical falls had more associated environmental factors than nonmechanical falls (57.3% vs 28.8; P b .01) but fewer syncope causes (0.9% vs 12.9%; P b .01). Howev- er, more than a quarter of nonmechanical falls also had associated envi- ronmental factors. Mechanical fall patients fell indoors less frequently than nonmechanical fall patients (54.1% vs 70.4%; P b .01) and had fall location recorded less frequently (22.9% vs 13.6%; P = .03). Mechanical fall patients lost consciousness or had an altered mental state less fre- quently than nonmechanical fall patients (4.6% vs 25.0%; P b .01) and also had a lower rate of dementia (9.6% vs 18.9%; P = .01).

Table 1

Demographic data between mechanical and nonmechanical fall patients

fall were taken from the practice guideline of Baraff et al for elder falls [12]. Data for such conditions/factors were taken from the history of

Variable Mechanical,

n = 218 (%)

Nonmechanical, P

n = 132 (%)

the present illness section of the clinician note.

We then explored whether patients labeled as having a mechanical fall vs patients who were not described as having had a mechanical fall had discrete ED evaluations. We examined the ED evaluation of el- derly fall patients in 4 categories: (1) history, (2) physical examination (PE), (3) diagnostic evaluation, and (4) safety assessment. Key history elements consisted of factors associated with falls as identified by the GED Guideline [11] and included the location of fall, comorbidities and other health problems, fall history, loss of consciousness or alteration of mental status immediately before or after the fall, activities of daily living, alcohol consumption, and certain medications. Key elements of the PE included an examination of gait, balance, foot problems, ortho- static hypotension, muscle strength, and cognition. Key elements of the diagnostic evaluation include complete blood count, electrolyte panel, electrocardiogram (ECG), x-ray, and computed tomography (CT). Finally, key elements of the safety assessment before discharge are a get-up and go test (a test for assessing physical mobility) [13] in the ED and a Physical therapy (PT) evaluation (gait, balance, and muscle strength) before disposition from ED. Finally, we explored whether me- chanical vs nonmechanical labels predicted follow-up events, 30-day and 6-month mortality, frequency of ED revisits, subsequent hospitali- zations, and recurrent falls.

Age, mean +- SD 80.5 (8.9) 79.3 (8.4) .20

Sex (male), n (%) 145 (66.5) 80 (60.6) .26

Race/ethnicity, n (%)

White 201 (92.2) 126 (95.5) .23

Black 6 (2.7) 4 (3.0) 1.00

Hispanic 4 (1.8) 0 (0) .30

Asian 8 (3.7) 2 (1.5) .24

Other 1 (0.5) 0 (0) 1.00

Primary insurance, n (%) .08

Medicare	191 (87.6)	143 (85.6)
Commercial	14 (6.4)	14 (10.6)
Company	7 (3.2)	0
Welfare	0 (0)	1 (0.8)
Self-pay	5 (2.3)	4 (3.0)
Other	1 (0.5)	0
Residence, n (%) Home with relative(s)	77 (35.3)	39 (29.5)	.68
Home alone	106 (48.6)	76 (57.6)
Assisted living	28 (12.8)	15 (11.3)
Skilled rehab facility	4 (1.8)	1 (0.8)
Acute rehab facility	1 (0.5)	0
Homeless	1 (0.5)	0
Unknown	0	1 (0.8)
Charlson comorbidity index, mean (SD)	6.8 (3.0)	6.6 (2.9)	.49
ED length of stay, median (IQR), h	5 (3-7)	6 (4-8)	.01
Hospital length of stay, median (IQR), d	3 (1-5)	2 (1-4)	.12

584 J. Sri-on et al. / American Journal of Emergency Medicine 34 (2016) 582-585

Overall, there was no difference between the frequencies of record- ed recommended PE between patients termed mechanical vs nonme- chanical fall (Table 2). Emergency department clinicians examined gait, balance, orthostatic hypotension, and foot problems in less than a quarter of all elderly fall patients.

More than half of all elderly fall patients had some diagnostic investiga- tion. Although the rate at which ECGs and CTs were performed for mechan- ical fall patients was less than for nonmechanical fall patients, there were no differences in the number of patients with Abnormal ECGs (ECG abnormal- ities [11.6% vs 5.2%; P = .23] or CT abnormalities [40.4% vs 31.3%; P = .20]). The most common ECG abnormality that we found was atrial fibrillation (6/

Table 2 The conditions/associated factors of fall and the key evaluation elements among mechan- ical and nonmechanical older adult ED fall patients

11 [54.5%]). Few elderly fall patients had a PT evaluation or performed the get-up and go test before disposition from the ED (Table 2).

In terms of disposition and short- and long-term outcomes, the ED disposition of patients was similar in terms of discharge to place of pre- admission residence, admission to the hospital, and admission to the observation unit. There were similar ED revisit rates, recurrent falls, sub- sequent hospitalizations, and death between mechanical and nonme- chanical fall patients (Table 3).

Discussion

Our exploration of the term mechanical fall revealed that mechanical vs nonmechanical falls are not clearly differentiated by the associated conditions/factors surrounding the fall nor do the terms guide a fall evaluation or predict outcomes.

The term mechanical fall implies that an external force (eg, environ-

Mechanical,

Nonmechanical, P

mental) caused the patient to fall and/or that there is no underlying pa-

out first. Our en not true of th mechanical isome causes, sociated with anical fall was atients had an

	n = 218 (%)	n = 132 (%)	thology of concern and/or the patients did not pass
Conditions/associated factors of fall			exploratory data show that these implications are oft
Environment	125 (57.3)	38 (28.8)	b.01 falls which are described as mechanical in nature. Bo
Poor light source	7 (3.2)	0	^.05 and nonmechanical fall patients had high rates of worr
Uneven or slippery surfaces	77 (35.3)	22 (16.7)	b.01
Loose rugs	13 (6.0)	2 (1.5)	_.06 such as poor balance, and high rates of comorbidities as
Steep stairs	10 (4.6)	3 (2.3)	.39 them. Furthermore, our study found that the term mech
Objects in pathway	12 (5.5)	7 (5.3)	.94 not used consistently; a quarter of nonmechanical fall p
Lack of handrails	4 (1.8)	1 (0.8)	^.65 environmental cause for their fall.
Inappropriate furniture	5 (2.3)	2 (1.5)	^.72 Our study showed little overall difference between
Aging/functional decline	59 (27.0)	44 (33.3)	.21
Weakness	12 (5.5)	14 (10.6)	.08 tions of the 2 groups indicating labeling patients as havi
Poor balance	48 (22.2)	33 (25.0)	.52 falls does not lead to a distinct evaluation approach. In s
Vision impairment	2 (0.9)	0	.53 the evaluation of mechanical fall patients was less c
Syncope and presyncope	2 (0.9)	17 (12.9)	^b.01 than the evaluation of nonmechanical fall patients. In ou
Other medical problems	4 (1.8)	9 (6.8)	.02
Delirium	3 (1.4)	6 (4.6)	_.09 nicians asked fewer mechanical fall patients about their f
Foot and footwear problem	4 (1.8)	1 (0.8)	.65 they asked of nonmechanical fall patients. A history of p
Unclear	38 (17.4)	39 (29.6)	b.01 one of the most important key history items for elder
History key elements			[6-8]. This information can help prevent future falls an
Indoor	118 (54.1)	93 (70.4)	^.01 morbidity, and many studies have recommended asking
Outdoor	50 (22.9)	21 (15.9)	.01
Not recorded	50 (22.9)	18 (13.6)	.03 tients this key history element [6-8]. Evaluating a patien
Fall history asked about	60 (27.5)	57 (43.2)	b.01 tors is not any more or less applicable for elderly pati
Loss of consciousness/Altered mental status	10 (4.6)	33 (25.0)	b.01 the cause of their fall. Mechanical falls may seem reass
Alcohol use	42 (19.3)	26 (19.7)	^.92 still a sign of potential decline.
Polypharmacy (>= 5 medications), n (%)	151 (71.6)	95 (71.9)	.93
Independence with ADLs	90/115 (78.3)	47/73 (64.4)	_.04 For follow-up events, there were similar rates of ED r
Dementia	21 (9.6)	25 (18.9)	.01 quent hospitalization; recurrent falls; and death at 7
Prior Hip fracture	18 (8.2)	7 (5.3)	.29 and 6 months after discharge from the ED. More imp
Physical examination key elements
Gait and/or balance evaluation	35 (16.1)	25 (18.9)	.49
Orthostatic evaluation	22 (10.1)	21 (15.9)	.11 Table 3
Cognitive assessment (orientation to	216 (99.1)	130 (99.5)	.61 The outcomes among mechanical fall and nonmechanical fall
time, place, person)			ED disposition place Mechanical Nonme
Muscle strength test	132 (60.5)	67 (50.8)	.07 fall, n = 13
Foot problem evaluation	3 (1.4)	2 (1.5)	.08 n = 218 (%)
Investigation evaluation Complete blood count	116 (53.2)	83 (62.9)	.07 Discharge to place of preadmission 120 (55.1) 67 (50.8
Electrolyte panel	116 (53.2)	83 (62.9)	.07 residence, n = 187
ECG, n = 127	69 (31.6)	58 (43.9)	.02 Transfer to hospital, n = 92 57 (26.2) 35 (26.5
New ECG abnormalities, n = 11	8 (11.6)	3 (5.2)	.23 Discharge to place of preadmission 19 (33.3) 19 (55.9

the fall evalua- ng mechanical ome instances, omprehensive r study, ED cli- all history than revious falls is ly fall patients d substantial elderly fall pa- t’s fall risk fac- ents based on uring but are

evisits; subse- days, 30 days, ortantly, there

chanical, 2 (%)

)

.74

.94

.04

Atrial fibrillation	5 (7.2)	1 (1.7)	.24	residence, n = 38
Sinus bradycardia	2 (2.9)	1 (1.7)	1.00	Discharge to skill rehab facility, n = 53	38 (66.7)	15 (44.1)	.04
ST abnormality	1 (1.5)	1 (1.7)	1.00	Institutionalization, n = 1	0	1 (2.9)	.90
X-ray, n = 275 178 (81.7)		97 (73.5)	.07	Transfer to observation, n = 67	37 (16.9)	30 (22.7)	.19
CT, n = 184	104 (47.7)	80 (60.6)	.02	Discharge to place of preadmission	23 (62.2)	26 (86.7)	.02
CT abnormality, n = 67	42 (40.4)	25 (31.3)	.20	residence, n = 38
Head CT abnormality, n = 56	33 (31.7)	23 (28.8)	.66	Discharge to skill rehab facility	14 (37.8)	3 (17.7)	.02
soft tissue injury Fracture	17 (16.4) 10 (9.6)	8 (10.0) 5 (6.3)	.21 .41	Discharge to nursing home New nursing home, n = 4	0 4 (0.9)	1 (3.3) 0	.63
Subarachnoid hemorrhage	1 (1.0)	5 (6.3)	.09	Revisit within 30 d	34 (15.6)	28 (21.2)	.18
subdural hematoma	1 (1.0)	4 (5.0)	.17	Revisit within 6 mo	94 (43.1)	55 (41.7)	.79
Cerebral hemorrhage	1 (1.0)	0	1.00	Recurrent fall in 30 d	14 (6.4)	12 (9.1)	.36
Cerebral contusion	1 (1.0)	0	1.00	Recurrent fall in 6 mo	45 (20.6)	34 (25.8)	.27
Safety assessment before ED disposition Get-up and go test	8 (3.7)	0	.08	Subsequence hospitalization in 30 d Subsequence hospitalization in 6 mo	23 (10.6) 71 (32.7)	16 (12.1) 38 (28.8)	.65 .46
Patients have PT evaluation	26 (11.9)	20 (15.2)	.39	Death within 30 d	1 (0.5)	1 (0.8)	1.00
Abbreviation: ADLs, activities of daily living. Death within 6 mo 3 (1.4) 6 (4.6) .07

J. Sri-on et al. / American Journal of Emergency Medicine 34 (2016) 582-585 585

were very high rates of recurrent falls, ED revisits, and hospitalizations in the mechanical fall group, indicating that there is likely some under- lying pathology in these so-called mechanical falls.

Our study shows that nothing distinguishes a mechanical fall from a nonmechanical fall. The terms mechanical and nonmechanical are not clearly defined. There are no particular conditions/etiologies associated with them, and there are no associated discrete, nonoverlapping evalu- ations of mechanical and nonmechanical fall patients. The terms also do not predict outcomes, suggesting that they are not useful. In past years, the terms intrinsic and extrinsic have been used to describe falls. Howev- er, it is clear now that falls are multifactorial. All fall patients need a thor- ough evaluation at least following GED guideline to determine the etiology of the fall to impact outcomes.

Limitations

This study was conducted at a single hospital. The results of this study may not be generalizable to EDs in other areas. Our sample size was relatively small. The number of patients with undesirable outcomes was limited. In addition, chart reviews are limited in their ability to ac- curately measure quality of care. There is a potential for missing data if the patients sought care outside our hospital’s network. Causes of falls were based on ED charts and not some independent criterion standard evaluation. Finally, the rate of recurrent falls may be lower than the ac- tual rate depending on how often patients reported these events to their health care provider.

Conclusion

In conclusion, our data show that the term mechanical fall is unclear and inconsistently used; the terms mechanical and nonmechanical falls overlap to a great extent and do not describe distinct entities, nor do they lead to a specific evaluation or predict outcomes. We propose elim- inating the term mechanical fall. A fall, mechanical or not, is often a sen- tinel event leading to a decline in the older patient.

Acknowledgments

This study was funded by the Hartford Foundation’s Center of Excellence.