What Are Femoral Neck Fractures?

Femoral neck fractures often occur in the elderly. With the increase of life expectancy, the incidence of femoral neck fractures is increasing. Especially with the aging of the population, it has become a serious social problem. There are two major problems in clinical treatment of fracture nonunion and femoral head ischemic necrosis. To date, many aspects remain unsolved in the treatment and outcome of femoral neck fractures.

Basic Information

English name: femoral neck fractures
Visiting department: orthopedics
Multiple groups: Seniors

Common causes: Associated with osteoporosis, decreased bone strength, and degeneration of the hip muscles in the elderly
Common symptoms: Hip pain, unable to stand and walk
Contagious: no

Causes of femoral neck fractures

There are two basic factors that cause fractures in the elderly. The decline in osteoporotic bone strength and dense nourishment of blood vessel holes in the upper femoral neck area can weaken the femoral neck biomechanical structure and make the femoral neck fragile. In addition, due to the degeneration and slow response of the hip muscles in the elderly, it can not effectively offset the harmful stress of the hips. In addition, the hips are subject to heavy stress (2-6 times the weight), and the local stress is complex and changeable. Violence, such as slipping on the ground, falling from the bed, or sudden twisting of the lower limbs, can cause fractures even without obvious trauma. Fractures of the femoral neck in young adults are often caused by severe injuries such as car accidents or falls from heights. Fatigue fractures are those who gradually develop fractures due to excessively long and heavy load labor or walking.

Clinical manifestations of femoral neck fractures

Symptoms

The elderly complain of hip pain after falling and cannot stand and walk. Think of the possibility of femoral neck fracture.

2. Signs

(1) The deformed iliac crest has mild hip flexion and external rotation deformity.

(2) Pain: In addition to spontaneous pain in the hip, the pain is more noticeable when moving the affected limb. When the heel or trochanter of the affected limb is beaten, the hip is also painful, and there is often tenderness below the midpoint of the inguinal ligament.

(3) Swollen patellar femoral neck fractures are mostly intracapsular fractures, and there is not much bleeding after the fracture, and they are surrounded by extra-articular thick muscle groups. Therefore, it is not easy to see swelling locally.

(4) Dysfunction: Patients with displaced fractures cannot sit up or stand after the injury, but there are some cases of non-displaced linear fractures or impact fractures that can still walk or ride a bicycle after the injury. Special attention should be paid to these patients, not to cause a non-displacement stable fracture to become a displaced unstable fracture due to a missed diagnosis. In displacement fractures, the distal end is displaced upwards by traction by the muscle group, thereby shortening the affected limb.

(5) The gross trochanter on the affected side is elevated : the greater trochanter is above the zygomatic-sciatic tubercle; the horizontal distance between the major trochanter and the anterior superior iliac spine is shorter than that on the healthy side.

Femoral neck fracture examination

X-ray examination serves as a reference for the classification and treatment of fractures. In some non-displaced fractures, the fracture line can not be seen on the X-ray film taken immediately after the injury. CT, magnetic resonance examination is available, or after 2 to 3 weeks, the fracture line is clear due to the absorption of bone in the fracture part. Ground is displayed. Therefore, anyone who suspects a femoral neck fracture in clinical practice should be treated as an insert fracture, although the fracture line is temporarily not seen on the X-ray film, and re-examined after 2 to 3 weeks. Another situation that is easy to miss is multiple injuries, which often occur in young people. Because some obvious injuries, such as femoral shaft fractures, conceal femoral neck fractures, it is important to pay attention to hip examinations for such patients.

Diagnosis of femoral neck fracture

The final diagnosis requires an X-ray examination of the hip joint, especially for linear or impact fractures.

Femoral neck fracture complications

1. Femoral neck fracture does not heal

Nonunion of femoral neck fractures is more common. The nonunion rate of femoral neck fractures is reported to be 7% to 15%, with the highest incidence in limb fractures.

2. Avascular necrosis of the femoral head

Avascular necrosis of the femoral head is a common complication of femoral neck fractures. With the progress of treatment in recent years, the fracture healing rate can reach over 90%. However, the rate of ischemic necrosis of the femoral head has not decreased significantly so far.

Femoral neck fracture treatment

Surgical treatment

The best treatment for femoral neck fractures is manual reduction and internal fixation. As long as there is a satisfactory reduction, most internal fixation methods can achieve a healing rate of 80% to 90%, and non-healing cases require surgical treatment in the future and only 5% to 10%. Even if femoral head necrosis occurs, only one-third of the cases require surgery. Therefore, the treatment principle of femoral neck fracture should be: early non-invasive reduction, reasonable multiple nail fixation, early recovery. Artificial joint replacement is only suitable for those over 65 years old with Garden III and IV fractures and can tolerate surgical anesthesia and trauma.

2.Reset internal fixation

The results of reduction and internal fixation methods are not only related to the degree of fracture damage, such as the degree of displacement, the degree of comminution, and the blood flow damage, but also the correctness of the reduction, the correctness of the fixation, and the postoperative rehabilitation.

3. Artificial prosthesis replacement.