Shoulder injuries associated with handling luggage presenting to U.S. emergency departments: 2003-2017

Abstract

BACKGROUND:

Demand for travel for both work and leisure continues to rise in the U.S. However, handling luggage subjects the shoulder to excessive physical loads.

OBJECTIVE:

To report national estimates, demographic characteristics, and injury mechanisms of patients presenting to U.S. emergency departments with luggage-associated shoulder injuries.

METHODS:

This cross-sectional, retrospective study analyzes the National Electronic Injury Surveillance System (NEISS) database (2003-2017) to identify annual cases of luggage-associated shoulder injuries presenting to U.S. emergency departments.

RESULTS:

On average, 1,811 luggage-associated shoulder injuries presented to U.S. emergency departments annually (95% Confidence Interval: [C.I.] 1,123–2,499). Patients were commonly females (62.3%; 57.9%–66.8%) sustaining sprains, strains, or muscle tears (60.1%; 52.6%–67.7%). The majority of patients sustained shoulder injuries while lifting their luggage (70.1%; C.I. 64.9%–75.2%). Injuries were most often observed in patients 40–49 (21.5%; C.I. 16.5%–26.5%) and 50–59 (24.9%; C.I. 20.2%–29.6%) years of age. However, those sustaining shoulder injuries due to falls to the ground were significantly older (p < 0.001) on average than those with injuries from lifting or pulling their luggage.

CONCLUSIONS:

We recommend that at-risk individuals for luggage-associated shoulder injuries take certain precautions when handling heavy baggage to reduce said chances of injury.

Keywords

Travel baggage airport transportation lifting

1 Introduction

Technological advancements and economic prosperity have made it possible for people to travel faster, further, and more frequently in the United States [1, 2]. U.S. airlines, for example, have reported figures vacillating between about 700 and 800 million passengers being carried in a given year to both domestic and international destinations over the past decade [3]. Likewise, rail systems continue to increase in popularity [4]. However, the rising demand for transportation services means that travelers will necessarily be handling luggage more often, which has been shown to increase the risk for musculoskeletal injuries of the neck, lower back, and upper extremity [5, 6]. Of these, the most commonly injured anatomic region associated with handling luggage is the shoulder, which may be subjected to excessive physical loads in a variety of awkward positions. For example, both storing and removing belongings from overhead bins can force the shoulder into positions of excessive abduction, extension, or external rotation [7]. This is especially concerning when considering that the shoulder is also one of the most commonly injured regions in the body overall by virtue of its propensity for instability and proclivity for rotator cuff injury [8 –10].

The pushing and pulling forces experienced while carrying heavy bags, possibility of tripping and falling over bulky belongings, and utilization of repetitive overhead movements to access storage areas can all cause shoulder injuries in travelers. Moreover, these injuries can range from muscle pains to tendon tears and even fractures; the risk for injury is potentiated if hurried travelers handle their personal items while distracted in an effort to comply with stringent departure schedules [11 –15]. Despite this, the national injury burden that handling luggage may have on the shoulder has never been investigated outside of several single-institution studies limited to those employed as flight baggage handlers at airports [16 –18]. These few studies did in fact reveal an increased risk of severe pain and subsequent decreased workplace productivity secondary to handling of luggage. Thus, the relationship between handling luggage and acute shoulder injury in the general population associated with travel merits further examination [18].

The purpose of this study was to report national estimates, demographic characteristics, and injury mechanisms of patients presenting to U.S. emergency departments between 2003 and 2017 with travel-associated shoulder injuries related to handling luggage. We hypothesized that the physical act of lifting luggage would most commonly be associated with injury, relative to other mechanisms.

2 Methods

2.1 Data sources

The Consumer Product Safety Commission’s (CPSC) publicly available and deidentified National Electronic Injury Surveillance System (NEISS) was used for this cross-sectional, retrospective epidemiological study. The database is a nationally representative probability sample of about 100 designated hospital emergency departments, and serves the purpose of collecting and reporting product or activity associated injuries in the United States. The NEISS sample stratifies by both hospital size and geographic location in order to ensure that national estimates of emergency department visits remain unbiased, and do not over represent injuries which are more likely to occur in densely populated settings. Statistically validated, reliable weighted national estimates and sampling errors for queried injuries may be derived from this database. Specific data collection methodologies, quality control precautions, and other general information are available on the CPSC webpage [19 –21].

Key variables included in the NEISS database include: the date of treatment; the case record number; the age, gender, race and ethnicity of the patient; the injury diagnosis; the body part affected by the injury; disposition (treated and released, admitted, etc.); the product involved (if any) in the injury; the location where the injury occurred; whether fire was involved in the injury; a narrative of the incident and scenario leading to the injury.

2.2 Data analysis

In this study, each yearly sample in the NEISS database was queried between 2003 and 2017 for shoulder injuries associated with handling luggage (Product Code: 1623). In addition to suitcases and explicitly categorized luggage, this product code also included attach $\overset{´}{e}$ cases, cosmetic bags or cases, duffle bags, and suit bags; in addition, this product code specifically excludes backpacks, knapsacks, book bags and back carriers, footlockers, otherwise unspecified bag types, and any tools used for luggage transport (such as dollies, hand carts, or other carriers) from our study [21]. 683 unique cases were identified in the NEISS database during this period, which yielded an overall weighted national estimate of 27,163 shoulder injuries associated with handling luggage occurring between 2003 and 2017. These weighted national estimates were calculated using the svyset function in Stata/IC 15.1 statistical software, which uses the “PSU,” “Weight,” and “Stratum” columns intrinsic to the NEISS database as variable inputs for its primary sampling unit, sample weight, and strata fields, respectively, in order to output weighted national estimates and standard errors for given queries, which can subsequently be summed across years for analyses of trends [22, 23]. Each of the 683 case narratives was individually read, reviewed, and classified by shoulder injury mechanism, including: falls to the ground caused by imbalance from handling or tripping over luggage; sustaining injury from lifting the luggage off the ground or overhead; injury resulting from pulling luggage while still in contact with the ground; other mechanisms.

National estimates, standard errors, and 95% confidence intervals were derived using the svyset function in Stata/IC 15.1 [22]. Significance of trends and hypothesis testing in the total national survey estimates were determined using adjusted Wald tests, for which p values <0.05 (two-sided) were considered significant. Of note, it is inappropriate to use the more commonly encountered independent t-tests when analyzing weighted, stratified, and large-sample survey data from a national database. This is because the typical and requisite underlying statistical assumption that observed cases are independent of each other is potentially violated. Therefore, we use the adjusted Wald test because it is able to take into account the survey design (i.e., weighting, stratification, and degrees of freedom) in order to yield accurate post-estimation results, and is commonly employed for these purposes.

2.3 Sources of funding

This study received no external funding support given the use of this publicly available, deidentified dataset from an online, government-sponsored website.

3 Results

The annual estimated national number of shoulder injuries associated with handling luggage that presented to U.S. emergency departments between 2003 and 2017 are depicted in Table 1. There was no significant change in the national number of injuries between 2003 (N = 1,772; C.I.: 1,025–2,519) and 2017 (N = 2,669; C.I. 1,286–4,051) (p = 0.31), as determined using the adjusted Wald test. On average, 1,811 shoulder injuries associated with handling luggage presented to U.S. emergency departments each year (C.I. 1,123–2,499).

Table 1
Weighted national estimates of shoulder injuries associated with handling luggage presenting to U.S. emergency departments, 2003-2017

Year National estimate of cases Standard error 95% confidence interval

2017 2,669 693 1,286–4,051

2016 2,523 321 1,883–3,162

2015 2,104 406 1,293–2,914

2014 1,424 304 819–2,030

2013 1,749 333 1,085–2,413

2012 1,692 322 1,049–2,334

2011 1,882 292 1,300–2,464

2010 1,632 316 1,002–2,261

2009 1,392 277 839–1,945

2008 1,793 308 1,179–2,407

2007 1,518 262 995–2,041

2006 1,814 292 1,231–2,397

2005 1,576 376 826–2,326

2004 1,623 297 1,032–2,215

2003 1,772 375 1,025–2,519

Annual average (2003-2017) 1,811 345 1,123–2,499

Year	National estimate of cases	Standard error	95% confidence interval
2017	2,669	693	1,286–4,051
2016	2,523	321	1,883–3,162
2015	2,104	406	1,293–2,914
2014	1,424	304	819–2,030
2013	1,749	333	1,085–2,413
2012	1,692	322	1,049–2,334
2011	1,882	292	1,300–2,464
2010	1,632	316	1,002–2,261
2009	1,392	277	839–1,945
2008	1,793	308	1,179–2,407
2007	1,518	262	995–2,041
2006	1,814	292	1,231–2,397
2005	1,576	376	826–2,326
2004	1,623	297	1,032–2,215
2003	1,772	375	1,025–2,519
Annual average (2003-2017)	1,811	345	1,123–2,499

The diagnoses and mechanisms of injuries for patients presenting to U.S. emergency departments with should injuries associated with handling luggage between 2003 and 2017 are shown in Table 2. Almost three-quarters of patients sustained their injuries while trying to lift their luggage (70.1%; C.I. 64.9%–75.2%). Another 15.9% (C.I. 11.4%–20.4%) of luggage-associated injuries resulted from falls to the ground, such as from tripping or being made off balance while holding said luggage. Only 6.3% (C.I. 4.2%–8.3%) of patients sustained shoulder injuries while pulling their luggage, and 7.7% (C.I. 4.9%–10.5%) were associated with other injury mechanisms. Most commonly, patients sustained a sprain, strain, or muscle tear (60.1%; 52.6%–67.7%). Another 14.6% (C.I. 10.3%–18.8%) of patients presented with generalized pain, whereas 8.9% (C.I. 6.3%–11.6%) experienced a dislocation, 4.4% (C.I. 2.5%–6.3%) a fracture, and 4.2% a contusion (C.I. 2.6%–5.7%); 7.9% (2.6%–5.7%) of patients sustained other types of injuries.

Table 2

Diagnoses and mechanisms of injuries for patients presenting to U.S. emergency departments with shoulder injuries associated with handling luggage, 2003-2017

Injury characteristics	Percentage	Standard error	95% confidence interval
Mechanism
Lifting (overhead or off ground)	70.1%	2.6%	64.9%–75.2%
Falling to ground	15.9%	2.3%	11.4%–20.4%
Other	7.7%	1.4%	4.9%–10.5%
Pulling	6.3%	1.0%	4.2%–8.3%
Diagnosis
Strain or sprain (including tears)	60.1%	3.8%	52.6%–67.7%
Pain	14.6%	2.1%	10.3%–18.8%
Dislocation	8.9%	1.3%	6.3%–11.6%
Other	7.9%	1.3%	5.3%–10.4%
Fracture	4.4%	0.9%	2.5%–6.3%
Contusions (abrasions)	4.2%	0.8%	2.6%–5.7%

Table 3 describes the demographic characteristics of the overall population of patients sustaining shoulder injuries while handling luggage that presented to a U.S. emergency department during our study period. There was a slight but significant peak of injuries sustained during the summer (27.2%; C.I. 23.4%–31.0%) as compared to the lowest proportion of injuries occurring during the fall season (20.9%; C.I. 17.6%–24.2%) (p = 0.03). The majority of injuries occurred in patients 40 to 49 years of age (21.5%; C.I. 16.5%–26.5%) and 50 to 59 years of age (24.9%; C.I. 20.2%–29.6%). Patients were most commonly white (53.0%; C.I. 43.6%–62.5%) females (62.3%; 57.9%–66.8%), though 30.6% (C.I. 20.2%–41.0%) of entries for patient race were not specified. Nearly all patients were treated and released (97.4%; C.I. 95.9%–98.8%), with an insignificant percentage requiring admission to hospital. 20.6% (C.I. 16.8%–24.3%) of injuries occurred in public settings, and 31.3% (C.I. 23.4%–39.1%) occurred at home; 44.9% (C.I. 38.2%–51.7%) occurred in an unknown location.

Table 3

Overall demographics of patients presenting to U.S. emergency departments with shoulder injuries associated with handling luggage, 2003-2017

Demographic variable	Percentage	Standard error	95% confidence interval
Age
0 to 9 years^a	0.4%
10 to 19 years^a	1.9%
20 to 29 years	8.9%	1.5%	5.9%–11.9%
30 to 39 years	16.0%	2.1%	11.8%–20.2%
40 to 49 years	21.5%	2.5%	16.5%–26.5%
50 to 59 years	24.9%	2.3%	20.2%–29.6%
60 to 69 years	11.4%	1.6%	8.2%–14.7%
70 to 79 years	10.6%	1.3%	7.9%–13.2%
80 years and older	4.4%	0.9%	2.5%–6.2%
Sex
Male	37.6%	2.2%	33.1%–42.0%
Female	62.3%	2.2%	57.9%–66.8%
Race
White	53.0%	4.8%	43.6%–62.5%
Black	11.5%	2.6%	6.3%–16.7%
Hispanic^a	3.2%
Race not specified	30.6%	5.2%	20.2%–41.0%
Disposition
Treated and released	97.4%	0.7%	95.9%–98.8%
Treated and admitted^a	1.5%
Location
Unknown	44.9%	3.4%	38.2%–51.7%
Home	31.3%	3.9%	23.4%–39.1%
Public	20.6%	1.9%	16.8%–24.3%

Legend: a - The estimate is considered to be potentially unstable due to the number of unweighted cases from the sample frame totaling <20, the weighted national estimate totaling <1200, or coefficient of variation >33%. Therefore, no standard errors or confidence intervals are provided; the unstable percentage estimate is provided for reference purposes only. Variable results with sample frame totals <20 cases or percentages <0.1% were omitted from this table, resulting in percentage totals not necessarily summing to 100%.

Lastly, the average ages of patients presenting to U.S. emergency departments with shoulder injuries associated with handling luggage are illustrated in a forest plot, categorized by the mechanism of injury (Fig. 1). Patients who experienced falls were significantly older (58.66 years; C.I. 55.27–62.06 years) on average than those sustaining injuries due to lifting (49.18 years; C.I. 46.97–51.39 years) or pulling (41.73 years; C.I. 35.60–47.86 years) mechanisms (p < 0.001). The average ages of patients sustaining shoulder injuries associated with handling luggage resultant from other mechanisms (50.30 years; C.I. 41.18–59.41 years) was expectedly insignificantly different from the afore mentioned mechanisms.

Fig. 1

Average ages of patients presenting to U.S. emergency departments with shoulder injuries associated with handling luggage by mechanism of injury, 2003–2017. This forest plot illustrates the average ages of patients sustaining shoulder injuries associated with handling luggage between 2003 and 2017, categorized by the mechanism resulting in said injury. The figure demonstrates that, on average, those sustaining falls to the ground were significantly older than those sustaining shoulder injuries resultant from pulling or lifting luggage.

4 Discussion

Our study is the first to quantify a previously underreported shoulder injury burden associated with handling luggage. For the past fifteen years, nearly 2,000 American patients per year have suffered a shoulder injury secondary to personal luggage handling which was sufficiently disabling to merit a visit to an emergency department. The majority of reported injuries were sprains, strains, and muscle/tendon tears, but a considerable proportion were more critical injuries, such as dislocations and fractures. Importantly, we highlighted that women are most at risk for luggage-associated injuries of the shoulder, and that nearly one-third of injuries occur while still at home. Lastly, we demonstrated that older individuals were more likely to sustain luggage-associated shoulder injuries, often resultant from falls to the ground while trying to handle their luggage.

Based on our results, we make several recommendations for travelers in order to avoid shoulder injuries associated with handling luggage (Table 4). First, travelers should pack lightly whenever possible: given that the majority of observed injuries were sprains, strains, and muscle tears sustained while people lifted their luggage, it is probable that more manageable loads would also be less likely to severely strain joints and muscles [24]. However, care should be taken to ensure that belongings are firmly secured within baggage, since loose luggage is likely to shift loads upon being lifted and increase the risk of injury [25]. Second, patients with a history of shoulder surgery or instability should refrain from over extending their arms in order to store belongings in overhead compartments. Instead, they may benefit from requesting assistance from experienced transportation staff when placing or removing belongings from overhead bins, or even consider storing belongings underneath their seats if space and travel protocols permit [26, 27].

Table 4
Summary of recommendations for reducing the risk of shoulder injury in travelers handling luggage

Number Recommendation

1 Pack lightly whenever possible, but ensure that belongings are firmly secured and do not shift when lifted

2 Avoid over extending arms to reach overhead bins (especially if there is a history of shoulder surgery or instability)

3 Avoid reaching to pull luggage off of conveyor belts during baggage claim (allow luggage to move to a position directly in front of body for safer lifting position)

4 Deliberately take breaks when carrying luggage for long distances to avoid shoulder muscle fatigue and injury

5 Read Occupational Safety &Health Administration (OSHA) guidelines for safe lifting techniques when manually handling luggage

Number	Recommendation
1	Pack lightly whenever possible, but ensure that belongings are firmly secured and do not shift when lifted
2	Avoid over extending arms to reach overhead bins (especially if there is a history of shoulder surgery or instability)
3	Avoid reaching to pull luggage off of conveyor belts during baggage claim (allow luggage to move to a position directly in front of body for safer lifting position)
4	Deliberately take breaks when carrying luggage for long distances to avoid shoulder muscle fatigue and injury
5	Read Occupational Safety &Health Administration (OSHA) guidelines for safe lifting techniques when manually handling luggage

Third, travelers should refrain from extending their arms in an effort to reach and pull on luggage still on a conveyor belt during baggage claim. Once belongings have arrived at a point directly in front of their bodies, travelers will have more time and space to safely lift their luggage [25]. Fourth, travelers should be mindful of shoulder muscle fatigue when handling luggage, especially for those who have been carrying their luggage for long distances. Overall, a fatigued muscle is more susceptible to injury, and suggests that regular breaks from carrying luggage when traveling may help reduce the risks of strains, sprains, and muscle tears [28, 29]. Fifth, all travelers should be encouraged to read the publicly available recommendations posited by the Occupational Safety & Health Administration (OSHA) for the manual handling of luggage, which include education about proper lifting techniques and the benefits of using two hands to perform lifts irrespective of where a handle might be located [30].

Of course, the benefits of these preventive measures can only be realized if there is sufficient compliance with safety recommendations related to handling luggage. This will likely require a concerted effort by luggage manufacturers, airlines and their staff, and travelers themselves. For instance, luggage manufactures may produce luggage with features conducive to safe handling recommended by OSHA, as well as designs that reduce the risk of fatigue from pulling. This might include multiple handles closer to waist height, greater diameter wheels which function as larger levers and reduce the amount of force needed to turn said wheels around axels when pulling, and inner straps to help secure loose belongings [25, 31]. Additionally, to reduce the need for overhead movements, airlines may elect to increase storage space underneath seats, and conduct safety checks at the boarding gate that enforce size and weight limits for carry-on luggage [32, 33]. Lastly, for travelers especially at risk for shoulder injuries, physicians may play a key role in helping to reinforce the importance of following safety recommendations. For example, we found that older women were most at risk for experiencing luggage-associated shoulder injuries due to falls to the ground. This is particularly concerning because the prevalence of osteoporosis in older women –about 16%–is four-fold higher than in men [34]. Thus, falls to the ground due to tripping over or being pulled down by heavy belongings are more likely to result in fragility fractures not only in the shoulder region, but potentially even in the hip, which carries substantial morbidity and mortality risks [35 –37]. Therefore, clinicians should advise at-risk patients intending to travel to follow these aforementioned safety recommendations [38]. By taking multiple steps towards improving compliance with safety guidelines, the national burden of luggage-associated shoulder injuries may be reduced.

4.1 Limitations

Of course, analyses making use of nationally representative survey samples inherently have certain limitations. First, our data only includes patients who presented at U.S. emergency departments. Therefore, patients solely presenting at outpatient clinics or urgent care centers were not captured by this study [39, 40]. As a result, we consider our findings to represent conservative estimates of the national burden of luggage-associated shoulder injuries, highlighting cases sufficiently severe to merit visiting an emergency department. In addition, specific details of the injuries are not mentioned in the database, meaning that distinctions cannot be made between open or closed fractures, muscle strains versus full-thickness tears, or even which specific bones or joints of the shoulder girdle were affected. This may have allowed for a more in-depth analysis of risk factors, expected long-term sequelae, and time to recovery than the database presently allows.

5 Conclusion

Travel often serves as a relaxing hobby for people of all ages, from students and families seeking restful vacations to retirees using their newly flexible schedules to visit a variety of interesting places. However, a luggage-related shoulder injury has the potential to derail these otherwise positive travel objectives by imparting considerable, negative health consequences on travelers, and may decrease productivity for those returning to work thereafter. For at-risk populations, taking certain precautions such as asking for assistance with handling heavy baggage or allotting enough time to deliberately handle belongings more carefully can reduce the chances of sustaining a shoulder injury. Furthermore, awareness of this appreciable incidence of luggage-related injuries may spur public educational efforts which emphasize proper lifting techniques and ways to minimize forceful eccentric loads which are known to potentiate the development of rotator cuff injury.

Conflict of interest

None to report.

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