Low Energy Trauma and Frailty

Frailty is a state of vulnerability associated with aging, physiological decline and depleted reserves. Frail people have impaired homoeostasis, such that a relatively minor stressor event (such as a fall) brings with it a disproportionately high risk of adverse outcomes including disability, prolonged hospitalization, and mortality.


In musculoskeletal medicine, frailty is often recognized in relation to “weakened bones” associated with osteoporosis, loss of muscle mass (sarcopenia), weakness, and impaired exercise tolerance. Frailty is better understood as a whole-person concept, incorporating not only weakened musculoskeletal system, but endocrine, neurological, cardiovascular, immune and psychological systems, among others as well.


Because frailty increases with age, and because the world’s population is getting older, it is likely that the incidence of frailty-associated injuries will rise as well. Improved recognition, assessment, and management of frailty in the older population are therefore essential for preventing injury, optimizing outcomes if injury is sustained, and choosing treatments appropriate for the patient’s frail state.



Structure and Function

Frailty is associated with age, co-morbidities and disability, but there is some evidence that it can exist independent of them. The hallmark of frailty is decreased reserve and resistance to (relatively minor) stressors, owing to decline in multiple physiologic systems, musculoskeletal included.


Musculoskeletal decline manifests as loss of lean body mass, decreased strength and endurance and poor balance. Accordingly, frailty can be seen as a cause or precursor to falls, and to a greater likelihood of injury if a fall is sustained.


Poor nutrition and sarcopenia are important contributors to the development of frailty. Sarcopenia is an age-related loss of muscle mass which results in a decrease in strength, mobility, and function. It is not only associated with the falls which cause the injury, but with the complications that affect outcomes from injury.


In addition to the physical associations of frailty, recently developed “bio-psycho-social” models acknowledge that frailty has many psychological and social components that may further decrease resilience to challenges. Depression, social isolation, and low socioeconomic status are obvious examples of psychosocial factors associated with human functioning that may impact negatively on outcomes to stressors.


Patient Presentation 

Frailty can be defined with the frail phenotype model, which is based on observable physical characteristics, or the frailty index model, which is based on a deficit accumulation.


Frail Phenotype Model

The frail phenotype is recognized by the presence or absence of five variables: unintentional weight loss; exhaustion; low physical activity; slow walking speed; and weakness. Frailty is defined by the presence of at least three of these variables. The term “pre-frail” is applied to those with one or two variables.


Table 1: The Frail Phenotype Model

Frailty Index Model

In the frailty index model, frailty is seen as a quantifiable property of multidimensional risks, rather than a binary state (of “present” or “absent”). In this model, frailty increases because of a cumulative decline of function across multiple physiological systems.


Many variables can be used to indicate deficits and create an index based on the presence of absence of deficits. To create a meaningful index, there should at least 20 variables which are age-related, associated with adverse outcomes, and cover several organ systems.


Items for consideration on a Frailty Index include symptoms, signs, diseases, disabilities, or laboratory abnormalities.


Typically, a person would be considered as frail if deficits are recorded in more than a given fraction (say 20%) of the measured variables. For example, if we were to create an index from 85 measured variables and deficits were found in 25 of the variables – then the FI would be 25/85, or 29%.


The advantage of using an index is that a continuous variable allows for a more quantitative approach to the measurement of frailty, assessing severity and temporal changes, especially after injury and other stressors. Likewise, an index can measure the response to treatment interventions. On the other hand, use of an index requires a more comprehensive clinical evaluation.


It may be helpful to use a simplified assessment tool as a means of determining whether a more comprehensive assessment is indicated. One such “Frailty Assessment Form”, as proposed by Fairhall, et al, is shown in Figure 1. This form may help identify the frailty phenotype and count deficits that may contribute to a frailty index rating.


Figure 1: The “Frailty assessment form” reproduced from Fairhall, et al, Treating frailty-a practical guide BMC Med. 2011; 9: 83. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3146844/

Research is ongoing for the development and validation of trauma specific frailty indices. This research aims to identify the most sensitive and specific variables that predict poor outcomes after trauma. At the least, a validated trauma specific frailty index may help identify those patients in need of particular attention, or to help guide the appropriate treatment after injury. Just as the standard principles of fracture treatment may not apply in the case of injuries caused by metastatic cancer, so too these standard principles might have to be modified for patients too frail to benefit from them.


Objective Evidence

Beyond the general metrics of frailty, frailty in the musculoskeletal system can be quantified. Bone mineral density can be used to measure osteopenia, and sarcopenia can be defined through measurements of muscle mass (Figure 2). In one study abdominal CT scans were used to measure psoas major muscle cross sectional area at the L4-L5 intervertebral disc level and found that each square centimeter of psoas muscle cross-sectional area was associated with a 20% decrease in the need for dependent living.


Figure 2: CT Scans of normal muscle mass (top) and sarcopenia (bottom). As shown in the annotated figures to the right, all the muscle tissue seen on the CT is highlighted in red. (Image courtesy of Giovanni Marasco https://www.hindawi.com/journals/cjgh/2021/6669480/)



Frailty is associated with aging and population ageing is accelerating rapidly worldwide. There were approximately 461 million people older than 65 years in 2004, whereas that number is expected to grow to an estimated 2 billion people by 2050. Notably, the 80 and older age demographic is the fastest growing cohort.


Globally, the reported prevalence of frailty in the community rises from 4% in people aged 65-69 years to 26% in those 85 years or older (Figure 3).


Figure 3: Increasing prevalence of frailty as a function of 5-year age cohort.

Frailty is more common among females, for two reasons. One reason is at baseline, they have less muscle mass (and thus lower reserves to offset losses). Also, frailty is, as shown, particularly common among the particularly aged, and females tend to live longer than males. (In the United States, approximately 75% of all people 90 years of age or older are female.)


Data from a 20-year review of an Australian trauma registry showed in 2010, older patients accounted for a third of major trauma cases. The relative contribution of falls to this major trauma had increased from 46% to 69% (an average of 2.1% per year) over that 20-year period.



Treatment Options and Outcomes

Although more challenging to manage than younger patients, older trauma patients can still achieve good outcomes after injury. In general, the risk of poorer outcomes from any degree of trauma in older patients is heightened among those pre-existing chronic medical conditions, especially when associated with objective evidence of frailty. Higher scores on frailty indices are an independent predictor of in-hospital complications, greater discharge dependency, and death.


One of the biggest challenges in treating frail patients is fluid resuscitation and maintenance. There is a very fine line between insufficient and excessive fluid administration, but with appropriate hemodynamic monitoring in the intensive care unit, proper resuscitation can be achieved. Likewise, the sweet spot between giving too much pain medication and too little must be sought.


Because frailty is associated with lower physiologic reserves and vulnerability to relatively minor physiological stress, there is a strong argument for the use of so-called damage control orthopaedics in older patients with poly-trauma. The hallmark of damage control orthopaedics is to limit the initial treatment to simple stabilization techniques, however imperfect they may be. Patients may return to the operating room for more definitive surgery if their condition allows it. This approach may decrease the risk of hypothermia, acidosis and coagulopathy, adult respiratory distress syndrome, and multiple organ dysfunction.


Another important consideration in the management of musculoskeletal injury in frail patients is the involvement of geriatricians and the application of gerontology management principles. Whether the injured frail patient belongs on a medical service,  orthopaedic surgery service, or some hybrid of the two is a question beyond the scope of this text. Nonetheless, it goes without saying that all caregivers must be aware of, and attentive to, the patient’s physiological vulnerability.


Several strategies have been emerging in the last 20 years to improve the management of older trauma patients from the time of presentation.


Emergency departments might fail to meet the specific needs of older patients. In particular, training in gerontology principles and procedures, pain management, and resuscitation protocols should be universal. To address this issue, there has been a move towards the implementation of specialized Geriatric Emergency Departments, based on guidelines developed between Emergency and Geriatrics physician and nursing organizations. This approach should not only improve the management of the injury directly but also the underlying patient features of the patient’s presentation (e.g., dementia, delirium, and malnutrition) that negatively impact outcomes overall.

For older patients with hip fractures, services managed jointly by geriatricians and orthopaedic surgeons can help achieve optimal outcomes.

Best practice management of older patients can never be complete without consideration of advance directives and wishes for end-of-life care. A “save life at all costs” mindset is often the unwritten default position but may be markedly inappropriate.


Along those lines, the default position among some orthopaedic surgeons, “there is a fracture, and I have to fix it” may lead to unnecessary operations. For some frail patients, especially those who no longer walk, non-operative fracture care may be more than adequate. 


Risk Factors and Prevention

Frailty, as a marker of vulnerability, is itself a risk factor for poor outcomes. The main risk for developing frailty is, in turn, aging – which is a better outcome than its alternative, of course. (A glib means of avoiding frailty is to not live long, just as one can avoid all income taxes by not earning any money. Neither are necessarily appealing solutions.)


Many frailty-prevention steps are worthwhile, even in the absence of conclusive data proving their effectiveness. These interventions include optimizing nutrition; exercising; ensuring adequate sleep and rest; and maintaining social connection and self-expression. Happy people have measurably better resistance to illness.


Sarcopenia and weight loss might be ameliorated by exercise programs and nutrition supplementation. Clinical evaluation for medical diseases that cause exhaustion (e.g., heart failure) should be undertaken for its own sake. Reducing polypharmacy and in turn medication-related adverse events is likewise imperative for all patients. Older persons with frailty should be assessed for visual and hearing difficulties: both can lead to isolation, and visual impairment is a distinct risk for falls.




Hospitals were originally places for poor people to die, with admissions occurring at the end of the course of a disease, rather than at its beginning. Many religious institutions established hospitals accordingly not so much to provide health care, but to ensure a good death. Florence Nightingale has been credited with changing the focus in hospitals, and the nursing profession especially, to the provision of healthcare.



Key Terms

Damage Control Orthopaedics, frail phenotype, frailty index, trauma specific frailty index