Hip Fracture

Although sports injuries to the knee, ankle, and shoulder have been well documented, injuries to the pelvis, hip, and thigh get little attention because of their low prevalence. Unfortunately, severe consequences may result if these injuries are improperly managed.[1, 2, 3]

Femoral neck stress fractures were mainly seen in military recruits due to a triad of activity that is new, strenuous, and highly repetitive. However, as a result of self-imposed fitness regimens of recreational athletes, over the last 20 years the number of these injuries has been increasing in nonmilitary populations. In contrast, contact sports such as football, rugby, and soccer are usually the cause of most fractures of the hip. Stress fractures occur in normal bone undergoing repeated submaximal stress. As the bone attempts to remodel, osteoclastic activity occurs at a greater rate than osteoblastic activity. When these cumulative forces exceed the structural strength of bone, stress fractures occur.[4, 5, 6]

Stress fractures occur mainly at the femoral neck and are classified as either tension (at the superior aspect of the femoral neck) or compression (at the inferior aspect of the femoral neck). See the images below.

Hip fractures are classified as intracapsular, which includes femoral head and neck fractures, or extracapsular, which includes trochanteric, intertrochanteric, and subtrochanteric fractures. The location of the fracture and the amount of angulation and comminution play integral roles in the overall morbidity of the patient, as does the preexisting physical condition of the individual. Fractures of the proximal femur are extremely rare in young athletes and are usually caused by high-energy motor vehicle accidents or significant trauma during athletic activity. Other causes may be an underlying disease process such as Gaucher disease, fibrous dysplasia, or bone cysts.

Identification and initiation of treatment is imperative in attempts to avoid complications, such as avascular necrosis (AVN). AVN is more common in patients in the pediatric and adolescent age groups. This outcome is due to the precarious nature of the blood supply to the subchondral region of the femoral head, which does not stabilize until years after skeletal maturity, after which collateral flow develops.

For excellent patient education resources, visit eMedicineHealth's First Aid and Injuries Center. Also, see eMedicineHealth's patient education article Total Hip Replacement.

New guidelines for management of hip fracture in the elderly released

The American Academy of Orthopaedic Surgeons released new guidelines on the management of hip fractures in patients over the age of 65. Recommendations supported by strong evidence include the following:[7, 8]

• Regional analgesia can be used to improve preoperative pain control in patients with hip fracture.

• In patients undergoing hip fracture surgery, similar outcomes can be achieved with general or spinal anesthesia.

• Arthroplasty should be used for patients with unstable (displaced) femoral neck fractures.

• Use of a cephalomedullary device is recommended for the treatment of patients with subtrochanteric or reverse obliquity fractures.

• In asymptomatic postoperative hip fracture patients, a blood transfusion threshold of no higher than 8g/dl should be used.

• Intensive post-discharge physical therapy improves functional outcomes.

• Use of an interdisciplinary care program in hip fracture patients with mild to moderate dementia improves functional outcomes.

• Multimodal pain management should be used after hip fracture surgery.

Frequency

United States

• An estimated 340,000 hip fractures occur each year. Estimates indicate that in 2040, approximately 500,000 hip fractures will occur.

• Nine of 10 hip fractures occur in patients aged 65 years and older, and 3 of 4 occur in women.

• White females have been reported to be twice as likely to fracture their hips than black and Hispanic females. This frequency has been associated with a metropolitan setting, increased caffeine use, alcohol use, sedentary lifestyle, psychotropic drug use, and senile dementia.

• The rate of fractures is low in adolescent and young athletic populations, estimated to be less than 2% of all hip fractures (one hundredth of adult hip fractures).

The hip is a ball-and-socket joint composed of the acetabulum and the head of the femur. The femoral head is connected to the shaft by the femoral neck. These are supported by a network of trabecular bone.

Two other important landmarks on the proximal femur are the greater and lesser trochanters. These 2 structures are the main muscle attachment sites for the proximal bone. The iliopsoas muscle is connected to the lesser trochanter, and the abductors and short rotator muscles act through their insertion on the greater trochanter. In addition, many additional muscles attach along the intertrochanteric line, and, along with the muscles, they bring with them an abundant and redundant blood supply, which is conducive to healing. This is in contrast to the intercapsular femoral neck, which is prone to healing complications.

The blood supply to the femoral head has been studied extensively and has been found to change substantially during development. Until the cartilaginous growth plate forms a barrier at age 4 years, the major blood supply comes from the medial and lateral circumflex arteries (metaphyseal arteries), which arise from the deep femoral artery. After age 4 years, the posterosuperior and posteroinferior arterial branches of the medial femoral circumflex bypass the growth plate and form the main blood supply to the femoral head. During adolescence, the growth plate fuses and the metaphyseal vessels again become significant, traveling along the femoral neck. Fractures in this area can disrupt this delicate blood supply, leading to AVN, the most severe complication of this fracture.

The ball-and-socket joint provides most of the inherent stability of the hip joint, while allowing for a large range of motion. Additional stability is provided by the thick capsule and strong ligamentous structures that actually enforce the capsule, namely the iliofemoral, pubofemoral, and ischiofemoral ligaments. These ligaments are taut with internal rotation, which limits motion, and become lax with external rotation.

Motion about the hip occurs in the sagittal, frontal, and transverse planes. During normal gait, motion occurs in all 3 planes, and normal activities occur within the range of 120 º flexion, 20 º extension, 40 º abduction, 25 º adduction, and 45 º external and internal rotation.

The biomechanics of the neck-shaft angle, which averages 135 º and 10-15 º of anteversion, allows for a unique arrangement. This permits angular movements of the thigh to be converted to rotatory hip motion.

Patients with hip fractures may present in a variety of ways, ranging from an 80-year-old woman reporting hip pain after a trivial fall to a 30-year-old man in hemorrhagic shock after a high-speed motor vehicle accident.

Stress fractures usually manifest more insidiously, with an otherwise healthy person reporting pain related to activity and not healing with the conservative treatments suggested by their primary care doctor.

Although the classic presentation of a hip fracture is an elderly patient who is in extreme pain, a young, healthy athlete usually has the same presentation. The affected leg is externally rotated and may be shortened. The extremity shortening occurs because the muscles acting on the hip joint depend on the continuity of the femur to act, and when this continuity is disrupted, the result is a shorter-appearing leg. Assessing peripheral pulses and checking Doppler pressures to assure vascular patency is very important.

The patient with a stress fracture may present more subtly, reporting pain in the anterior groin or thigh. This pain increases with activity and can persist for hours afterward. The pain can progress to a point of consistency, even without activity. This pain generally expresses itself in the groin; however, it can also be referred to the knee. An antalgic gait pattern is often present. Signs and symptoms usually involve a diffuse or localized aching pain in the anterior groin or thigh region during weight-bearing activities that is relieved with rest. Night pain is also common.

A study by Brännström et al that included 408,000 older adults reported an association between antidepressant medications and hip fracture before and after the initiation of therapy. Further investigations are needed to study this association.[9]

Findings of the physical evaluation of the patient with a hip fracture may include the following:

• Testing reveals a painful hip with limited range of motion, especially in internal rotation.

• Pain is noted upon attempted passive hip motion. The heel percussion test also produces pain. Placing a tuning fork over the affected hip may also produce pain

• Ecchymosis may or may not be present.

• An antalgic gait pattern may be present.

• Deep palpation in the inguinal area produces discomfort. Tenderness to palpation is noted over the femoral neck. This area may also be swollen.

• Increased pain on the extremes of hip rotation, an abduction lurch, and an inability to stand on the involved leg may indicate a femoral neck stress fracture. If a femoral neck stress fracture is suggested, it must be excluded. Missing this diagnosis could lead to a completely displaced femoral neck fracture, AVN, nonunion of the bone, and eventual varus deformity.

Factors such as muscle fatigue, (which leads to abnormal gait patterns and altered stress distribution), training errors, improper footwear, and poor training surfaces can predispose an athlete to the development of stress fractures.

See the list below:

• If the diagnosis of hip fracture is still under consideration after taking into account the patient's history and presentation, laboratory studies should be ordered based on the patient and the potential for surgery. Laboratory studies to consider may include the following:

  • Complete blood cell (CBC) count

  • Electrolytes evaluation

  • Serum urea nitrogen value

  • Creatinine value

  • Glucose level

  • Urinalysis (UA)

  • Prothrombin time (PTT)

  • Activated partial thromboplastin time (APTT)

  • Arterial blood gas (ABG) determination

• These studies are used to determine the patient's medical condition before surgery and to allow correction of any abnormalities before surgical intervention.

See the list below:

• In addition to the recommended laboratory studies in a patient suspected of having a hip fracture, the physician should also obtain a chest x-ray film and an electrocardiogram (ECG) tracing to further assess the patient's medical condition before any surgical intervention.

• X-ray films are always indicated to determine which type of fracture, if any, is present. Anteroposterior (AP) views of the pelvis and hip and cross-table lateral x-ray films are usually sufficient to evaluate potential fractures. Rotating the affected leg internally or externally can increase the sensitivity of these radiographs. See the images below.

  Anteroposterior view of the pelvis with a displaced femoral neck fracture.

  Lateral view of a displaced femoral neck fracture.

• If the clinical picture is highly suggestive of a fracture or stress fracture and the x-ray findings fail to demonstrate a fracture, magnetic resonance imaging (MRI), linear tomography, or bone scanning can be useful in defining otherwise imperceptible fractures.

• A bone scan displays a radiographically occult fracture 80% of the time 24 hours after an injury, and it also shows almost all fractures after 72 hours. Negative bone scan findings virtually exclude the diagnosis of a stress fracture.

• MRI is able to show areas of decreased signal in the marrow of the involved bone soon after the injury. Because of the increased prevalence of bilateral involvement, consider performing imaging studies on the contralateral hip when a stress fracture is suggested.

Rehabilitation Program

Physical Therapy

The treatment of femoral neck fractures, intertrochanteric hip fractures, and most tension femoral neck stress fractures requires surgical intervention. Stress fractures occur most often in the femoral neck and are classified according to the location (ie, inferior or compression, superior or tension). Tension fractures have a poor prognosis and tend to be unstable. Compression fractures may heal with conservative management.

Compression fractures are most commonly treated with several days of rest followed by protected, crutch-assisted weight bearing. Frequent serial x-ray films are recommended to monitor fracture healing and progress and to assess for any changes. The operative treatment of tension stress fractures and hip fractures is discussed in Surgical Intervention.

Medical Issues/Complications

The most commonly used classification system for femoral neck fractures is the Garden classification. The fractures are divided into 4 groups according to the degree of displacement and fracture fragments.[4, 5, 6] This classification system gives guidance for treatment options and surgical implants. The following 4 groups comprise this classification system:

• Garden type I: Incomplete fracture with valgus impaction, as shown below

  Garden I femoral neck fracture. Note the valgus impaction with compression of the superior femoral head-neck junction.

  Lateral view of a Garden I femoral neck fracture. Compression of the head-neck junction inferiorly.

• Garden type II: Complete fracture without displacement

• Garden type III: Complete fracture with partial displacement of the fracture fragments

• Garden type IV: Complete fracture with total displacement allowing the femoral head to rotate back to an anatomic position

This classification can be further simplified into nondisplaced, Garden I and II, or displaced Garden III and IV fractures.

Classification of intertrochanteric hip fractures is based on a system introduced by Evans in 1949. This system is based on the fracture pattern and the ability to obtain a stable reduction. Evans recognized the importance of restoring the posteromedial cortex as a contributing factor to fracture stability. Others classify intertrochanteric fractures by the number of fracture fragments present; however, for ease of description and simplicity, these fractures are best classified as follows:

• Stable: Fractures with an intact posteromedial cortex

• Unstable: Fractures with comminution of the posteromedial cortex, fractures with diaphyseal extension

The classification system used most commonly for pediatric hip fractures is that of Colonna. In this classification, the fracture prognosis is dependent on the location of the injury and its interference with the blood flow to the femoral head.

• Type I: Transepiphyseal fractures, account for 8% of pediatric hip fractures, AVN rate approaches 100%

• Type II: Transcervical fractures, account for 45% of pediatric hip fractures, 80% are displaced, AVN rate approaches 80%

• Type III: Cervicotrochanteric fractures, account for 30% of pediatric hip fractures, AVN rate of 20-30%

• Type IV: Intertrochanteric fractures, account for 10-15% of pediatric hip fractures, fewer complications than types I-III

A study by Shin and Gillingham classified stress fractures based primarily on MRI findings.[10] The 3 basic categories were compression, tension, and displaced fatigue fractures. Compression side injuries were further subdivided on the basis of whether a fatigue line, which appears as a linear band of low-signal intensity lying perpendicular to the line of force across the femoral neck, was present.

The 2 subtypes are those that demonstrate a fatigue line less than 50% of the femoral neck width and those with a fatigue line greater than or equal to 50%. Tension side findings are subtle; their hallmark is increased signal intensity at the superior femoral neck on T2-weighted and short inversion time inversion recovery (STIR) images. Displaced fractures can be identified on plain radiographs.

Complications associated with poorly treated or misdiagnosed stress fractures are considerable. AVN, nonunion, varus deformity, osteonecrosis, and completely displaced femoral neck fractures may occur. These complications can lead to serious, life-altering changes in function and the patient's ability to ambulate efficiently and perform activities of daily living.

Surgical Intervention

Garden types I and II femoral neck fractures are surgically stabilized with closed reduction and internal fixation. Garden types III and IV are controversial in the type of implant used for treatment. In younger patients, closed or open reduction is recommended. In less active older patients, prosthetic replacement is recommended (see the images below). Patients with intertrochanteric hip fractures require surgical stabilization.

In acute (or chronic) displaced femoral neck tension stress fractures, most authors recommend aggressive treatment with internal fixation with percutaneously placed cannulated screws (see the images below). Postoperative treatment is similar as above, with crutch-assisted touch-down weight-bearing ambulation for the first 6 weeks and partial weight bearing for the subsequent 6 weeks. Thereafter, a supervised physical therapy program is outlined for progressive activity, lower extremity strengthening, and full weight-bearing ambulation.

Treatment of pediatric hip fractures requires expedient evaluation and, usually, surgical reduction and stabilization for displaced fractures. Timing of treatment is important and may play a role in the final outcome. A retrospective cohort study by Pincus et al that included 42,230 hip fracture patients reported an increase in complication risk (6.5% vs 5.8%) when patients waited more than 24 hours for surgery.[11]

Consultations

Femoral neck fractures and intertrochanteric hip fractures occur most often in elderly populations, who generally have other medical diagnoses. The fracture may have been due to a medically related problem such as a syncopal episode, dehydration, overmedication, or vertigo. The cause of a fall must be explored, and consultation with an internal medicine specialist is obtained to help rule out medical reasons leading to a fall and to obtain medical clearance for treatment and timing for surgical intervention. The reason for surgical treatment of hip fractures is to allow early patient mobilization and, hopefully, avoid associated medical complications from inactivity.

Supplementation with high dose oral vitamin D (≥800 IU daily) may help prevent hip fractures and other nonvertebral fractures in persons ≥65 years of age.[12]

Consultation with a pediatric specialist is recommended for assistance in pediatric hip fractures. Complications of pediatric hip fractures include AVN, premature physeal closure, femoral shortening, coxa vara, short femoral neck, trochanteric arrest, and nonunion.

Rehabilitation Program

Physical Therapy

Compression side stress fractures are usually treated with conservative care, using MRI to identify the minority of patients who warrant internal fixation. If no fatigue line on MRI greater than 50% of the width of the neck is present, rest and crutch-assisted touch-down weight-bearing gait are initiated. Recommend interruption of all aggravating activities until the patient is free from pain. This is followed by gradual introduction of weight-bearing activities to the limit of pain, progressively increasing activity until the patient returns to his or her previous level of function. Weekly x-ray films are taken to monitor changes in fracture status, and any sign of fracture displacement requires surgical intervention.

Medical Issues/Complications

If a significant compression stress fracture is initially apparent on the x-ray film, a more aggressive treatment plan must be initiated because of the tendency for fracture displacement and its associated complications. Closed reduction and internal fixation is recommended. Postoperatively, these patients are allowed to return to athletic activity once fracture healing and remodeling are complete, which may require up to 12 months. The internal fixation devices may be removed 12-18 months after surgery. An additional period of 6 weeks of protected activity is recommended to allow restoration of bone strength, before engaging in excessive athletic conditioning and activity.

Those patients who have sustained a tension-type stress fracture of the femoral neck require surgical stabilization because of the high prevalence of displacement. Following fixation, a standard progressive rehabilitation protocol is recommended. Protected touch-down weight-bearing ambulation with crutches is initiated postoperatively for 6 weeks, under the supervision of a physical therapist. Hardware may be removed 12-18 months following surgery.

Rehabilitation Program

Physical Therapy

Physical therapy in the maintenance phase focuses on more dynamic and functional training to ensure that the patient is able to safely return to his or her previous lifestyle. For athletes, sport-specific training must be incorporated, and the physical therapist must evaluate the overall condition of the hip and lower extremity in order to provide recommendations to the physician and patient. In elderly individuals, physical therapy continues until the patient has reached his or her maximum potential with range of motion and strength and until he or she is able to independently complete all required activities of daily living.

Nearly all patients with a femoral fracture are in significant pain, and parenteral analgesia should always be a consideration. Preoperative prophylactic antibiotics are recommended for the patient undergoing immediate internal fixation, with the usual dose being 1 g of a first-generation cephalosporin.

Prophylactic antibiotics are also indicated for open fractures. In a clean laceration smaller than 1 cm, an IV bolus of 1 g of a first-generation cephalosporin is adequate. An antibiotic that covers gram-negative organisms should be added for a laceration larger than 1 cm. With a laceration that has an extensive soft-tissue injury or appears moderately contaminated, 1.5 mg/kg of gentamicin or tobramycin should also be added. If the laceration appears grossly contaminated, penicillin should be added to cover clostridial infections.

The results from one study of elderly patients (65 y and older) noted that opioid analgesia can be used for postoperative hip surgery pain control without concern for a direct link to postoperative delirium.[13]

Class Summary

Antibiotic therapy must be comprehensive and cover all likely pathogens in the context of the clinical setting.

Cefazolin (Ancef, Kefzol, Zolicef)

First-generation semisynthetic cephalosporin that arrests bacterial cell wall synthesis, inhibiting bacterial growth. Primarily active against skin flora, including Staphylococcus aureus. Typically used alone for skin and skin-structure coverage. IV and IM dosing regimens are similar.

Tobramycin (Nebcin)

Used in skin, bone, and skin-structure infections caused by S aureus, Pseudomonas aeruginosa, Proteus species, Escherichia coli, Klebsiella species, and Enterobacter species. Indicated in the treatment of staphylococcal infections when penicillin or potentially less toxic drugs are contraindicated and when bacterial susceptibility and clinical judgment justifies its use.

Ampicillin and sulbactam (Unasyn)

Drug combination of beta-lactamase inhibitor with ampicillin. Covers skin, enteric flora, and anaerobes. Not ideal for nosocomial pathogens.

Gentamicin (Gentacidin, Garamycin)

Aminoglycoside antibiotic for gram-negative coverage. Used in combination with both an agent against gram-positive organisms and one that covers anaerobes.

Class Summary

Pain control is essential to quality patient care. Analgesics ensure patient comfort, promote pulmonary toilet, and have sedating properties, which are beneficial for patients who have sustained trauma or who have sustained injuries.

Morphine (Astramorph, Depodur, Duramorph)

DOC for analgesia because of reliable and predictable effects, safety profile, and ease of reversibility with naloxone.

Various IV doses are used; commonly titrated until desired effect obtained.

Ketorolac (Toradol)

Inhibits prostaglandin synthesis by decreasing the activity cyclooxygenase, which results in decreased formation of prostaglandin precursors.

As may be expected, each athlete with a hip fracture is treated on an individual basis. To return to play, the athlete should be off all pain medications, be relatively pain free, and have no return of symptoms during sports-specific activities.

Complications related to poorly treated or misdiagnosed stress fractures are considerable. AVN, nonunion, varus deformity, chronic pain, and completely displaced femoral neck fractures may occur and may lead to serious life-altering changes in function and the patient's ability to ambulate efficiently.

The prognosis for hip fractures is dependent on the age and condition of the patient and on the location and type of fracture. Athletes who sustain femoral neck stress fractures may or may not be able to return to their sport. Tension stress fractures are generally unstable and have an unfavorable prognosis. On the other hand, compression fractures are usually successfully treated with conservative measures and have a good prognosis for recovery. Hip fractures in elderly individuals have a mortality rate of 14-36% one year following surgery.

Patient education is a very important aspect to the rehabilitation process following hip fracture, regardless of the patient's age. Patients must be thoroughly informed about treatment options following their diagnosis, and they must understand the benefits and risks of treatment. If conservative treatment is an option, the patient may need instruction in the use of crutches initially to restrict weight bearing. A physical therapist should be involved in the patient's care for instructions in mobility training and reconditioning of the affected lower extremity. Patients are usually instructed in a home exercise program for continuing strengthening of the hip so that they are able to return to their previous level of activity.