21
Hip Fractures
Rengena E. Chan-Ting
Learning Objectives
Upon completion of the chapter, the student will be able to:
1. Identify the major risk factors for hip fractures in the geriatric population.
2. Recognize the signs and symptoms of hip fractures in the elderly.
3. Understand the consequences of hospitalization of an older adult with a hip fracture.
4. Explain postoperative complications in the elderly after a surgical hip procedure.
373 Material in this chapter is based on the following chapters in Cassel CK, Leipzig RM, Cohen HJ, Larson EB, Meier DE, eds. Geriatric Medicine: An Evidence- Based Approach, 4th ed. New York: Springer, 2003: Pottenger LA. Orthopedic Problems with Aging, pp. 651–667. Morrison RS, Siu AL. Medical Aspects of Hip Fracture Management, pp. 669–680. Selections edited by Rengena E.
Chan-Ting.
Case (Part 1)
Ms. Hope is a petite, 86-year-old Caucasian woman who lives indepen- dently in a three-story walkup apartment. She has not seen a physician for many years because she feels that she is in “good health.” One evening, as she was on her way to the bathroom, she tripped and fell on her left side. She was unable to stand due to excruciating pain. Luckily, she was able to pull the telephone close enough to her and call for an emergency ambulance. The emergency medical service brought Ms.
Hope to the emergency room with a diagnosis suspicious for a left hip fracture.
What is Ms. Hope’s chances for a full recovery?
General Considerations
Hip fractures are an important cause of mortality and functional depen- dence in the United States. Approximately 250,000 hip fractures occur annually in this country, and this number is expected to increase to over 650,000 by the year 2040 (1,2). For adults over age 65, the annual incidence of hip fracture is 818 per 100,000 persons (3), and women are two to three times more likely to experience a fracture than are men (4,5). Indeed, it is estimated that a white woman with an average life expectancy of 80 years has a 15% lifetime risk of fracture and by age 80, she has a 1% to 2%
annual risk (6). The mortality seen in the Medicare population following fracture is 7% at 1 month, 13% at 3 months, and 24% at 12 months (7).
For those patients who survive to 6 months, 60% have recovered their prefracture walking ability, 50% have recovered their prefracture ability to perform their activities of daily living (ADLs), and about 25% have recovered their prefracture ability to perform instrumental activities of daily living (IADLs) (8). However, after 1 year, only 54% of surviving patients are able to walk unaided, and only 40% are able to perform all physical ADLs independently (8). Furthermore, it is estimated that these total annual costs will increase to $16 billion by the year 2040 as a result of the projected increase in the number of adults over age 65.
Case (Part 2)
In the emergency room, Ms. Hope is seen by an orthopedic surgeon, who notes on physical exam that her left foot is externally rotated and that her left hip is shorter and tender to slight passive range of motion.
Radiographs and physical exam confi rm that she sustained a left femoral intertrochanteric neck fracture.
What is the leading factor that places Ms. Hope at an increased risk for a hip fracture?
Diagnostic Evaluation
Symptoms and Signs
The majority of hip fractures are easily diagnosed on the basis of history, physical exam, and standard radiographs. Ninety percent of hip fractures result from a simple fall, and the characteristics of the fall (direction, site of impact, and protective response), as well as certain patient charac- teristics, are recognized as important factors infl uencing the risk of fracture (9).
A diagnosis of osteoporosis is the leading factor that places patients at increased risk for hip fracture (9). Other patient characteristics that have
been shown to be associated with hip fracture include female sex, white race, maternal history of hip fracture, physical inactivity, low body weight, consumption of alcohol, previous hip fracture, nursing home residence, visual impairment, cognitive impairment, and psychotropic medication use (9). Patients with hip fracture typically report hip pain on weight bearing following a fall, and on physical exam the involved leg is often foreshort- ened and externally rotated.
Ancillary Tests
Plain radiographs (an anteroposterior view of the pelvis and a lateral view of the femur) hip confi rm the diagnosis in the majority of circumstances.
Occasionally, however, plain fi lms do not reveal evidence of a fracture despite a high clinical suspicion (e.g., pain with weight bearing after a fall).
In these cases, an anteroposterior view obtained with the hip internally rotated 15 to 20 degrees may reveal a fracture by providing an optimal view of the femoral neck (9). In circumstances in which all plain fi lms are nega- tive but clinical suspicion is still high, either a technetium-99m bone scan or magnetic resonance imaging (MRI) should be undertaken to rule out an occult fracture. The MRI appears to be a more sensitive test to detect early fractures as the bone scan can be normal within the fi rst 72 hours following a fracture. If all tests or imaging studies are unrevealing, other diagnoses to consider include fractures of the pubic ramus, acetabulum, or greater trochanter, trochanteric bursitis, or trochanteric contusion.
Classifi cation of Hip Fractures
Femoral Neck Fractures
Femoral neck fractures occur distal to the femoral head but proximal to the greater and lesser trochanters and are thus located within the capsule of the hip joint. The location of the fracture has important implications for healing and operative repair. Fractures in this region can disrupt the blood supply to the femoral head and can result in complications such as non- union and avascular necrosis of the femoral head. Thus, although nondis- placed and minimally displaced femoral neck fractures can often be treated by insertion of cannulated screws, displaced femoral neck fractures typi- cally require a hemiarthroplasty procedure to ensure appropriate fracture healing.
Intertrochanteric Fractures
Intertrochanteric fractures are located lateral to the femoral neck. These fractures occur in a well-vascularized metaphyseal region between the greater and lesser trochanters, and although intertrochanteric fractures
can be associated with considerable blood loss, they typically are not asso- ciated with the healing complications associated with femoral neck frac- tures. Intertrochanteric fractures are typically repaired by open reduction and internal fi xation (ORIF) with a compression screw device.
Subtrochanteric Fractures
Subtrochanteric fractures occur just below the lesser trochanter and account for only 5% to 10% of hip fractures. These fractures behave clinically like long bone fractures and are repaired either by insertion of an intramedullary device or by placement of a compression screw and long side plate.
Case (Part 3)
Ms. Hope is diagnosed as having a left femoral intertrochanteric neck fracture. The orthopedic surgeon had a lengthy discussion involving the risks and benefi ts of an ORIF surgical procedure, which will repair her femoral intertrochanteric neck fracture.
What are Ms. Hope’s management considerations and options at this point?
Management Considerations
Nonoperative Management
Nonoperative management should be considered for nonambulatory patients with advanced dementia. One recent study suggested that mortal- ity following fracture in patients with end-stage dementia exceeds 50% at 6 months (10). For such patients, aggressive pain management and a return to their previous home environment may be the most optimal treatment plan given the burdens associated with routine hospitalization (e.g., delirium, restraints, and painful therapeutic interventions, such as phleb- otomies, arterial blood gas monitoring, intravenous catheter insertions) (10,11).
Timing of Surgery
The timing of surgical repair of hip fracture may affect patients’ outcomes in two ways. Delay in surgical repair, and hence delay in return to weight bearing, could affect functional recovery. Conversely, failure to stabilize medical problems before surgery could increase the risk of preoperative complications. Although the scheduling of surgery is set by the orthope-
dist, the rate-limiting step in this process is often the internist’s preopera- tive medical evaluation.
For patients who are medically stable without active comorbid illness (e.g., active heart failure), surgical repair of hip fracture within the fi rst 24 to 48 hours of admission is associated with a lower 1-year mortality as compared to patients whose surgery is delayed. Patients who would benefi t from delay and further medical evaluation have not been well characterized. Until further data are available, it seems reasonable to attempt surgical repair for the majority of patients with hip fracture within 24 to 48 hours of admission to the hospital. Patients with active comorbid medical illness such as congestive heart failure, active infection (e.g., pneumonia), unstable angina, or severe chronic obstructive pulmonary disease probably would benefi t from a more extensive preoperative evalu- ation and medical management of their comorbid condition prior to repair of their fracture.
Case (Part 4)
Ms. Hope wants to return to her apartment, and continue to live inde- pendently; therefore, she decides to give consent for an ORIF surgical procedure.
What can be done to minimize preoperative and postoperative com- plications for Ms. Hope?
Antibiotic Prophylaxis
Antibiotic prophylaxis has become the standard of care for major surgical operations to prevent postoperative wound complications. In hip fracture, the timing of administration, the duration of antibiotic therapy, and the effectiveness of antibiotic prophylaxis have been the subject of some debate in the literature.
Available evidence supports the use of a single dose of an intravenous antibiotic with a long half-life to reduce the incidence of deep wound infec- tion, superfi cial wound infection, urinary tract infections, and respiratory tract infections. Given that the major pathogen appears to be Staphylococ- cus aureus, administration of a fi rst-generation cephalosporin (e.g., cefazo- lin 1 to 2 g intravenously) is recommended. For patients allergic to penicillin and cephalosporin and for patients admitted to hospitals in which methicil- lin-resistant S. aureus and Staphylococcus epidermidis are frequent causes of postoperative wound infections, vancomycin is probably the most appro- priate prophylactic agent (1 g intravenously) (12). Prophylactic antibiotic therapy should probably be initiated within 2 hours prior to surgery and continued for 24 hours following surgery.
Thromboembolic Prophylaxis
Venous thromboembolism is an important cause of morbidity and mortal- ity in postoperative hip fracture patients. Although thromboembolic pro- phylaxis is becoming a routine aspect of the care of the patient with hip fracture, a number of questions remain as to the choice of the optimal agent, the timing of prophylaxis, and the duration of prophylaxis post–
fracture repair. Studies to date have focused on four classes of agents:
heparinoids, antiplatelet agents, warfarin sodium, and the use of compres- sion stockings.
Patients receiving epidural/spinal anesthesia and receiving concurrent low molecular weight heparin should be monitored frequently for signs and symptoms of neurologic impairment. Aspirin has been found to signifi - cantly reduce the risk of deep venous thrombosis and pulmonary embolism by about one third, with much of this benefi t appearing to occur after the fi rst postoperative week. Aspirin also appears to have some benefi t, but to a lesser extent, and may be considered for patients at high risk for hemor- rhagic complications (13).
Overall, low-dose warfarin appears to be an effective agent for throm- boembolic prophylaxis. It appears more effective than aspirin but is probably less effective than low molecular weight heparin. The required international normalized ratio (INR) monitoring required for appropriate treatment with warfarin to prevent either over- or under-anticoagulation is a potential drawback. Conversely, it might be a better tolerated agent for patients wishing to avoid the discomfort of a twice-daily injection (14–17).
It is recommended that intermittent pneumatic compression devices be routinely used until the patient is ambulating on a routine basis. They have been shown to decrease the incidence of postoperative deep vein throm- bosis in urologic, neurosurgical, and general surgical patients (13). Com- pression stockings have also been evaluated in patients with hip fracture and have been shown to signifi cantly reduce the incidence of thromboem- bolic events as compared to no treatment (18).
There is strong evidence supporting the use of either low-dose heparin or low molecular weight heparin as prophylaxis for deep venous throm- bosis. The latter may be slightly more effective but is more expensive and has been associated with bleeding or hemorrhage in the spinal cord following epidural anesthesia in non–hip fracture populations. For these reasons, and until further data are available, low-dose heparin is probably the preferred agent. At present, it seems reasonable to begin anticoagula- tion on admission and continue prophylaxis until the patient is fully ambulatory and to extend prophylaxis further in patients in whom the risk of deep venous thrombosis may be increased (patients who exper- ienced prolonged immobility postrepair or patients for whom surgery was delayed).
Case (Part 5)
Ms. Hope underwent left ORIF and is now 3 hours postoperative and in the postoperative recovery unit. She is slowly weaned from breathing support and is now breathing on her own, as well as voiding urine after the indwelling catheter was discontinued. She continues to receive mor- phine for pain.
What are some postoperative management strategies that Ms. Hope could benefi t from?
Nutritional Management
Malnutrition has been associated with increased surgical morbidity and mortality (19,20), increased hospital length of stay (20), and poorer func- tional outcomes (20). It has been reported that as many as 20% of patients experiencing a hip fracture suffer from severe malnutrition (21). Interven- tions to improve nutritional status, therefore, might improve outcomes and decrease complications.
Oral protein supplementation appears to be benefi cial in reducing minor postoperative complications, preserving body protein stores, and reducing overall length of stay. They also have signifi cantly fewer complications at 6 months, signifi cantly higher albumin levels, and signifi cantly shorter overall lengths of stay than nonsupplemented subjects. Patients with evi- dence of moderate-severe malnutrition may benefi t from nocturnal enteral tube feeding if tolerated (see Chapter 11: Nutrition, page 189).
Urinary Tract Management
Urinary retention, incontinence, and urinary tract infections are com- monly observed in postoperative hip fracture patients (22). Because of the frequency of postoperative bladder problems, successful strategies to reduce voiding problems might lead to decreased morbidity.
Indwelling catheters should probably be removed within 24 hours of surgery. Evidence does not exist regarding the management of patients who continue to experience urinary retention following 48 hours of intermittent catheterization. In one study, those postoperative patients who had the indwelling catheter removed the morning after surgery had signifi cantly lower rates of urinary retention (23).
Case (Part 6)
On postoperative day 2 Ms. Hope is stable enough to be transferred to the ward, where she can accept visitors for an extended period of time.
Her family and friends notice that Ms. Hope is not at her baseline
Delirium
Delirium is a transient global disorder of cognition and attention character- ized by concurrent disorders of attention, perception, thinking, memory, psychomotor behavior, and the sleep-wake cycle (24,25), which may be the most frequent medical complication observed following hip fracture (26).
Delirium occurs in an estimated 11% to 30% of elderly general medical patients (27) and in 13% to 61% of patients with hip fracture (28). The occur- rence of delirium in hospitalized patients has been shown to increase length of stay, risk of complications, mortality, and institutionalization (29–33).
Furthermore, the majority of patients who develop delirium have at least some persistent symptoms that may linger as much as 6 months later.
In patients with a hip fracture, delirium has been associated with poorer functioning in physical, cognitive, and affective domains 6 months post- fracture and with slower rates of recovery (34,35).
Baseline risk factors for delirium appear to be fairly consistent across most studies. Advanced age, history of cognitive impairment, greater illness severity, and history of alcohol use appear to place hospitalized medical and surgical patients at increased risk for the development of confusion. A number of recurring potentially modifi able risk factors for developing delirium include electrolyte and metabolic laboratory abnor- malities, medications with psychoactive properties, and infection. Environ- mental manipulation and supportive reorientation appear to reduce the incidence of delirium and benefi t the acutely delirious patient, although more research addressing the optimal symptomatic management is needed.
A more thorough review of delirium may be found in Chapter 13: Depres- sion, Dementia, and Delirium, page 236.
mental status. She appears to have a short attention span and has acute and fl uctuating symptoms of disorganized thinking. A computed tomo- graphy (CT) scan of the brain reveals no acute pathology. Ms. Hope’s mental status improves over the next 72 hours.
What could account for Ms. Hope’s change in mental status?
Case (Part 7)
On postoperative day 6, Ms. Hope is seen by her primary care physician, who diagnoses her delirium, and medical therapy is initiated. A reha- bilitation consult has been made to help facilitate a discharge plan. The physiatrist recommends that Ms. Hope be transferred to a subacute rehabilitation facility for approximately 5 weeks prior to returning to her three-story walkup apartment. She agrees, and a transfer to the subacute rehabilitation facility is initiated.
Why was rehabilitation to a subacute facility initiated?
Rehabilitation
Rehabilitative services for hip fracture patients may include limb and joint mobilization and progressive exercises, physical and occupational therapy to regain mobility and independence in ADL, physician oversight of the therapy, psychological counseling, social work, restorative nursing services, and recreational services.
Rehabilitation is a shared responsibility with the surgeon who, depend- ing on the fracture and type of surgery, may have specifi c recommenda- tions about mobilization and weight bearing. Available data suggest that early mobilization can be done safely in selected patients, although the potential benefi ts of early mobilization have not been well studied and quantifi ed. In the case of interdisciplinary rehabilitation featuring geriatric assessment, there is some suggestion from randomized trials that these programs can improve functional outcome and increase the likelihood of patients returning to the community (36–47) (see Chapter 10: Exercise and Rehabilitation, page 168).
Case (Part 8)
Ms. Hope is now at the subacute rehabilitation facility and has worked hard over the past 5 weeks at regaining her strength and mobility. In addition, she has been adherent to her osteoporosis medical therapy which was started before her hospital discharge. Prior to discharge, from the subacute rehabilitation facility all patients undergo a fall assess- ment. This fall assessment involves an occupational therapist, who inspects the patient’s home environment and then makes recommenda- tions. Ms. Hope’s home assessment revealed that her hallway to the bathroom was fi lled with clutter including a loose rug that could have attributed to her fall. Recommendations from the fall risk assessment were followed through and Ms. Hope returned home.
Given that Ms. Hope has osteoporosis, what are her chances of falling and fracturing herself for a second time?
Fall Assessment
Patients who have fractured a hip have an increased risk of a subsequent fracture (48). Interventions to reduce the likelihood and number of subse- quent falls therefore might have benefi cial effects on outcome. Studies suggest that interventions to reduce the incidence of falls are more likely to be benefi cial if they focus on persons at risk for falls and if the interven- tions target specifi c risk factors or behaviors. Exercise and balance training also appear to be somewhat effective in decreasing fall risk. Because
persons who have sustained hip fractures are at higher risk of subsequent falls, these fi ndings may be generalizable to this population (49–54). A comprehensive review of fall assessment and prevention may be found in Chapter 20: Instability and Falls, page 366.
General Principles
• The mortality seen in the Medicare population following fracture is 7% at 1 month, 13% at 3 months, and 24% at 12 months. For those patients who survive to 6 months, 60% have recovered their prefrac- ture walking ability, 50% have recovered their prefracture ability to perform their activities of daily living, and about 25% have recovered their prefracture ability to perform instrumental activities of daily living. However, after 1 year, only 54% of surviving patients are able to walk unaided, and only 40% are able to perform all physical activi- ties of daily living independently.
• The risks and benefi ts of a surgical procedure for hip fractures in the elderly must be thoroughly considered. If surgery is the option, then other considerations include prophylactic antibiotics, throm- boembolic prophylaxis, nutritional management, and prevention of delirium.
• A diagnosis of osteoporosis is the leading factor that places patients at increased risk for hip fracture. Others include female sex, white race, maternal history of hip fracture, physical inactivity, low body weight, consumption of alcohol, previous hip fracture, nursing home residence, visual impairment, cognitive impairment, and psychotropic medication use. It is imperative that an etiology of the hip fracture be sought as to prevent further risks of fracture.
Suggested Readings
Anderson BC. Offi ce Orthopedics for Primary Care: Diagnosis and Treatment, 2nd ed. Philadelphia: WB Saunders, 1999. Provides treatment care for common disorders including hip pain, low back pain, cervical spine pain, as well as repeti- tive motion syndromes for nonsurgeons.
Morrison RS, Siu AL. Medical aspects of hip fracture management. In: Cassel CK, Leipzig RM, Cohen HJ, et al., eds. Geriatric Medicine, 4th ed. New York:
Springer, 2003:669–680.
Pottenger LA. Orthopedic problems with aging. In: Cassel CK, Leipzig RM, Cohen HJ, et al., eds. Geriatric Medicine, 4th ed. New York: Springer, 2003:651–668.
Zuckerman JD, Schon LC. Hip fractures. In: Zuckerman JD, ed. Comprehensive Care of Orthopedic Injuries in the Elderly. Baltimore: Urban & Schwarzenberg, 1990. Describes the principles and practices involved in proper care of orthope-
dic injuries in the elderly including fractures and soft tissue injuries, from the most common “classic” injuries to the distinctly uncommon injuries that would be more frequently encountered in younger patients.
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