Patients with femoral neck fractures usually present with a history of gradual insidious pain in the hip, groin, or knee, which worsens with exercise and activity. However, the pain is relieved with rest. Common features to all stress fractures may include insidious onset of pain, recent change in activity, pain aggravated by weight bearing and relieved with rest, history of trauma, menstrual irregularities and predisposing osteopenia. Physical examination of the affected limb will show a shortened, externally rotated and flexed leg.

X-ray plain films have low sensitivity in the diagnosis of femoral neck fractures. Nonetheless, they are routinely ordered as the first step in the workup for two main purposes: determining the site and extent of the fracture and ruling out any apparent fractures.

In many patients with femoral neck fractures, the X-rays will appear normal with no changes. However, if features do present, they may include sclerosis, callus, periosteal bone formation, or a fracture line.

The frog-leg X-ray view is sometimes used but not recommended, as it may lead to displacement and is usually not tolerated by patients. In cases where X-rays seem unobtrusive but symptoms still suggest the presence of a femoral neck fracture, other modalities may be used in the diagnosis such as magnetic resonance imaging (MRI). It will show a fracture line at the cortex surrounded by an intense zone of edema in the medullary cavity. Different patterns may be seen on MRI studies, depending on the patient being a young adults or an elderly person.

Bone scans may also be used in the diagnosis as they have the best sensitivity, even though their specificity is poor. They have a positive predictive value of 68% [16].

Both surgical and nonsurgical treatments are used in the management of femoral neck fractures in order to return patients to their previous normal function and prevent complications.

The first step in the management of the acute phase of femoral neck fractures is the control of painful symptoms. Acetaminophen or nonsteroidal anti-inflammatory drugs may be used to achieve this. However, they may be insufficient in some patients requiring the administration of a stronger pain reliever such as an opiate.

Compression fractures are usually more stable than tension ones, and nonoperative treatment will suffice in the management of these fractures with no need for surgical intervention. Nondisplaced tension femoral neck fractures should be stabilized with multiple parallel lag screws or pins. However, the management of displaced fractures may be different in each patient depending on certain factors such as age and activity.

Bed rest and the use of crutches are advised in patients suffering from nondisplaced fractures until the pain is relieved and passive movement of the hip is pain-free. There is still a high risk of displacement in these patients, which requires monitoring of fractures with serial X-rays. In some cases, the fracture may widen, which will require further management including open reduction and internal fixation with multiple pins or intramedullary hip screw [12].

Young patients suffering from displaced fractures are considered emergency cases with poor prognosis requiring early open reduction and internal fixation. In elderly patients, prosthetic replacement including hemiarthroplasty or total hip arthroplasty may be considered.

The prognosis of femoral neck fractures depends on the severity and the classification of the fracture. Displaced fractures in athletes may have poor prognosis and result in the ending of their career.

Blood supply may be affected in femoral neck fractures, which could result in avascular necrosis of the head of the femur [14]. Nonunion is also another common complication that may result from femoral neck fractures, leading to significant shortening of the femoral neck.

Inadequate fixation and reduction, shearing forces at the fracture site, and precarious vascularity are all risk factors for developing these complications [15]. There is a higher risk of developing osteonecrosis in young adults who have femoral neck fractures.

Femoral neck fractures rarely occur in adults younger than 50 years of age; however, they may result from a high-energy trauma such as a fall from height or a motor vehicle accident [5] [6]. Elderly people show a higher risk of developing intracapsular femoral neck fractures from simple falls [7] [8]. Several risk factors play a role in this, including multiple medical problems, poor bone density, and the high tendency to fall.

Athletes affected by femoral neck fractures usually suffer from insidious onset of pain over 2 or 3 weeks, which is related to a recent change of habits in training or equipment.

Women who develop femoral neck fractures may have the female athlete triad. This includes osteoporosis, amenorrhea, and poor eating, which leads to disturbances of the cardiovascular, endocrine, and gastrointestinal systems and to irreversible bone loss.

Femoral neck fractures rarely happen in young adults, but usually affect elderly people. Few studies reported the incidence of femoral neck fractures in some countries; however, the exact incidence is unknown. In a sample of 194 Israeli military recruits, 4.7% developed femoral neck fractures [9], and a higher rate was reported among female military recruits [10].

Variable outcome and poor prognosis are reported after different procedures for femoral neck fractures [11].

The mechanism of fractures differs between young adults and elderly people. The latter more commonly experiences falls directly onto the hip; elastic resistance in the fractured bone is generally deficient in those patients [12] [13]. In adults younger than 50 years of age, the most frequent mechanism is a high-energy trauma [12], which usually occurs while the hip is abducted. The abduction of the hip during the injury might result in a hip fracture-dislocation.

The weakest part of the femur is its neck, which makes it the most susceptible area for fractures. Femoral neck fractures may result in disruption of the blood supply, which may lead to morbidity. Hence, the classification of these fractures is very important.

Raising awareness through education is important in decreasing the risk of developing femoral neck fractures. Females, especially athletes, should maintain adequate bone density and muscle mass in order to prevent recurrent fractures. Sports-related injuries in general can be prevented through maintaining good flexibility. Seasonal athletes are advised to undergo preconditioning before participating in their particular sport. Increased blood flow and oxygenation to all tissues is important, and could be achieved through aerobic fitness.

Femoral neck fractures are common among elderly people, which is usually due to a low-energy trauma. Osteoporosis is a major risk factor for the developing of these fractures [1]. Young adults with normal bone may also suffer from femoral neck fractures due to a high-energy trauma, such as car accidents, falling from heights, or sport injuries [2]. Patients with femoral neck fractures usually present with a history of trauma and an insidious onset of pain, which is aggravated by activity and relieved by rest. Management of femoral neck fractures differs depending on the patient's age and the pattern of fracture. Usually, surgical intervention is required and includes hemiarthroplasty, total hip arthroplasty, artificial femoral head replacement, and internal fixation [3] [4]. Young athletes with displaced fractures may have poor prognosis with the inability to return back to their sport.

Femoral neck fractures occur in the femur bone, which is one of the leg bones. They may affect all age groups; however, the mechanism of the injury differs. Elderly people usually have weak bones due to a condition called osteoporosis, which increases the risk of developing femoral neck fractures from simple trauma such as falling down while walking. In young adults the fracture occurs due to a powerful trauma, including falling from heights, car accidents, and sport injuries.

Presentation

Insidious onset of pain in the hip or groin region is the most common symptom in patients with femoral neck fractures. Rest usually relieves the pain. There may be history of trauma, especially in young adults.

Diagnosis

X-rays, magnetic resonance imaging (MRI), and bone scans are used in the diagnosis of femoral neck fractures. The patterns seen on radiographic images may differ between elderly patients and young adults.

Management

Surgical intervention is usually required in order to prevent severe complications. Pain is managed by nonsteroidal anti-inflammatory drugs or acetaminophen. Stronger pain relievers, such as opiates, may be used to control pain if the preceding ones prove to be insufficient.

Outcome

The outcome of femoral neck fractures depends on the severity and the type of the fracture, which may be poor in displaced fractures. Young athletes with femoral neck fractures may not be able to return to their sport even after successful treatment.

Prevention

Education about femoral neck fracture and its risk factors helps in decreasing the risk of developing it. Maintaining good flexibility prevents sports injuries in young adults.

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