Fragility Fractures: Introduction

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Fragility Fractures: Introduction

Osteoporosis is a disease that is the most common bone disease in humans and is characterized by low bone mass and skeletal fragility, which results in an increased risk of fracture.  Annually, two million fractures are attributed to osteoporosis, causing more than 432,000 hospital admissions, almost 2.5 million medical office visits, and about 180,000 nursing home admissions in the USA (1).  Osteoporotic fractures, also known as fragility fractures, are those occurring from a fall from a standing height or less, without major trauma such as a motor vehicle accident. The most common areas affected are the spine, hip, wrist, humerus and pelvis.  The geriatric hip fracture fracture ranks as the third most expensive musculoskeletal diagnosis for the US Centers for Medicare and Medicaid Services (CMS), following only hip and knee arthroplasty (2).  Fractures of the hip and spine are associated with an increased mortality rate of 10 to 20 percent (3).  A personal history of vertebral fracture has been shown to increase the risk of subsequent fractures 5-fold and the risk of hip and other fractures 2 to 3 fold (4).  As the population ages, the number of patients at risk will continue to increase. The best interest of both the patient and society remains preventing these fractures.  Many strategies and programs have been proposed for patients who present with acute fragility fractures, but the overwhelming majority are not effectively treated to prevent secondary fractures.

Bone strength is typically determined by bone mineral density (BMD), bone geometry, degree of mineralization, microarchitecture and bone turnover (5).  The measurement of bone mineral density is vital in the detection of osteoporosis and fracture risk increased exponentially as BMD decreases (6). BMD measurements remain an integral component of all tools to assess an individual’s absolute risk of fragility fractures because it has been shown to be an excellent predictor of future fracture risk (6). This is usually done with using dual energy x-ray absorptiometry (DXA) and this is the gold standard for the diagnosis of osteoporosis and low bone mass.  The World Health Organization diagnostic classification defines osteoporosis by BMD at the hip or spine less than 2.5 standard deviations below peak bone mass (young adult gender matched population), which is more commonly labeled as T-score. Another metric is called the Z-score, which is matched to an age, sex and ethnicity matched reference population and used for people less than the age of 50. Serial measurements should be performed in accordance with medical necessity, expected response and consideration of the local regulatory requirements.  The National Osteoporosis Foundation recommends repeat BMD assessments every 2 years but more frequent testing may be warranted in certain clinical scenarios (6).

Figure 1 : WHO definition of osteoporosis

Figure 1: WHO definition of osteoporosis

Screening , or primary prevention, for individuals at risk for osteoporosis can be done by many different providers including family practice, internal medicine, rheumatology and orthopedics (Figure 2).  Any postmenopausal woman or man age 50 or older should be evaluated for osteoporosis risk in order to determine the need for BMD testing. Non-BMD factors that need to be factored in include age, previous fractures, falls, chronic glucocorticoid therapy, family history of hip fracture and smoking status.  Some professional organizations, such as the American Association of Clinical Endocrinologists recommend screening individuals that have osteopenia radiographically. Other organizations include heavy alcohol use or more than 2 drinks a day, low body weight and early menopause (7). In general, the more risk factors, the greater risk of fracture.   Osteoporosis is preventable and treatable and the burden for primary prevention does fall on primary care providers in most healthcare systems. Other qualified specialists may be able to step in and help with this burden and there is a need for improvement with primary prevention of fractures.  

Figure 2 : BMD Testing

Figure 2: BMD Testing

Many tools have been developed to help assess risk of fractures.  FRAX was developed in 2008 by the World Health Organization to calculate the 10-year probability of hip fracture and 10 year risk of a major osteoporotic fracture, which includes vertebral, hip, forearm or proximal humerus fracture.  This was designed for adults over the age of 50 (8). FRAX takes into account femoral neck BMD along with clinical risk factors including age, gender, low BMI, prior osteoporotic fracture, chronic oral glucocorticoid use, rheumatoid arthritis, parental history of hip fracture, current smoking, greater than 3 drinks per day and secondary causes of osteoporosis.  FRAX underestimates fracture risk in patients with recent fractures, multiple osteoporosis-related fractures, and those at increased risk for falling (2). It is readily available online (https://www.sheffield.ac.uk/FRAX/).  

QFracture was developed in the UK in 2009 and calculates 10 year hip and major fracture risk without BMD testing.  It is applicable to people aged 30-85 and also includes clinical risk factors, similar to FRAX. The clinical risk factors included in the QFracture algorithm in men and women are: age, sex, BMI, smoking, alcohol intake, glucocorticoids, asthma, cardiovascular disease, history of falls, chronic liver disease, rheumatoid arthritis, type 2 diabetes and tricyclic antidepressants. Additional factors used in women only are: hormone replacement therapy, parental history of hip fracture, menopausal symptoms, gastrointestinal malabsorption and other endocrine disorders.  The algorithm was undergone updates with the most recent in 2016 and is readily available online (https://qfracture.org/).  

The World Health Organization recommends considering BMD testing for adults suffering a fracture that are aged 50 or greater.  Despite compelling evidence that treatment of patients with fragility fractures can reduce the risk of future fractures by up to 50%, the majority of patients are not effectively treated to prevent a secondary fracture.  Due to this, many liaison programs and initiatives have been started including Own the Bone (OTB), AAOS’ Hip Fracture Clinical Practice Guideline, AAOS’ Appropriate Use Criteria, Performance Measures quality documents and IGFS’s Critical Care Pathways.  Many hospitals have also included a follow up DXA scan as part of quality measures.

Many methods have been explored in attempts to prevent secondary fractures.  Some of the programs have been staff based, some IT-based and some are a combination.  The most successful focus on a multi-disciplinary liaison service (3). A multi-disciplinary team usually involves clinicians and clinical nurse specialists and most have a goal of communicating with the patient while they are admitted with a fracture.  Capture the Fracture (http://www.capturethefracture.org/) was started by the International Osteoporosis Foundation to “facilitate the implementation of coordinated, mmulti-disciplinary models of care for secondary fracture prevention.”   This program provides a guide for secondary fracture prevention, a global map with a quality grading scheme to document fragility fractures.  

Figure 3:  Capture the Fracture framework breakdown ( https://capturethefracture.org/best-practice-framework )

Figure 3: Capture the Fracture framework breakdown (https://capturethefracture.org/best-practice-framework)

Another similar program that is gaining popularity is the Own the Bone (OTB) (https://www.ownthebone.org/OTB) program.  After a successful pilot program involving 14 enrollment sites, OTB was designated by the AOA as a national quality improvement project in 2009 (9). OTB was a quality improvement initiative, which included an online, web-based registry of de- identified patient history and fracture data that encouraged orthopedic surgeons to include bone health education and treatment as a distinct part of comprehensive fracture care. As a secondary benefit, the OTB registry has evolved into a large and robust dataset, which thoroughly characterizes fragility fractures presenting for inpatient care in the USA. This data enables benchmarking of institutions involved in the OTB program to help define best practices and to identify those factors and practices associated with suboptimal outcomes.  After institutional enrollment in the OTB program, with its minimal annual fee, access is provided to the secure online registry. Information regarding de-identified patient demographics, presenting fracture and previous fractures, medical comorbidities, and patient risk factors as well as prior BMD testing is obtained for registry entry. Health professional training occurs through national and regional meetings as well as online webinars, newsletters, site submitted Best Practice Materials, health professional calls, and online enrolled site forums. Patient education can be provided through face-to-face encounters between patients and members of the bone health care team as well as through online resources and educational materials on the OTB web site. 

Recent data was collected for 35,038 cases of fragility fractures using the OTB registry (9).  Seventy-three percent were female, Caucasian and post-menopausal. Hip fracture was the most commonly documented fracture at 54 percent, with spine fractures second at 11 percent.  The average femoral neck T-score was -2.06. This was comparable to other international studies (9).

Summary. In summary, It is widely accepted that bone health and osteoporosis have a significant impact on our current healthcare landscape.  Roughly two million fractures attributed to osteoporosis occur each year in the United States and estimates show this problem will continue to grow (2).  Bone strength for individuals at risk is typically determined by bone mineral density and determined by DXA. Tools, such as the FRAX and QFracture have been developed to determine 10 year risk of major fractures to help determine who needs treatments for either primary or secondary prevention.  Programs such as Own the Bone and Capture the Fracture have also been started to document fractures and educate both providers and patients on fragility fractures.


References

  1. Office of the Surgeon General (US) (2004) Bone health and osteoporosis: a report of the Surgeon General. Office of the Surgeon General (US), Rockville (MD)

  2. Curtis EM, Moon RJ, Harvey NC, Cooper C. Reprint of: The impact of fragility fracture and approaches to osteoporosis risk assessment worldwide. Int J Orthop Trauma Nurs. 2017;26:7–17. doi:10.1016/j.ijotn.2017.04.004

  3. Poole KE, Compston JE. Osteoporosis and its management. BMJ 2006; 333:1251.

  4. Ross PD, Davis JW, Epstein RS, Wasnich RD (1991) Pre-existing fractures and bone mass predict vertebral fracture incidence in women. Ann Intern Med 114(11):919–923

  5. Ahlborg HG, Johnell O, Turner CH, et al. Bone loss and bone size after menopause. N Engl J Med 2003; 349:327.

  6. Cosman F, de Beur SJ, LeBoff MS, et al. Clinician’s guide to prevention and treatment of osteoporosis. Osteoporosis Int. 2014;25:2359-81.

  7. Jeremiah MP, Unwin BK, Greenawald MH, Casiano VE. Diagnosis and management of osteoporosis. Am Fam Physician. 2015;92:261–8.

  8. National Clinical Guideline Centre (UK). Osteoporosis: Fragility Fracture Risk: Osteoporosis: Assessing the Risk of Fragility Fracture. London: Royal College of Physicians (UK); 2012 Aug. (NICE Clinical Guidelines, No. 146.) 4, Risk assessment tools (FRAX, QFracture, BMD)

  9. Carlson, B., Robinson, W., Wanderman, N. et al. Osteoporos Int (2018) 29: 2101. https://doi.org/10.1007/s00198-018-4585-7