Femoral neck fracture refers to the fracture between the lower femoral head and the base of the femoral neck, which is a common and frequent clinical disease and can be seen in all age groups, with the highest incidence in middle-aged and elderly patients.
I. High-risk individuals
There are two basic factors that cause fractures in patients. Osteoporotic bone strength decreases in middle-aged and elderly people, coupled with dense trophoblastic vascular pores in the upper femoral neck area, both of which can weaken the biomechanical structure of the femoral neck and make it vulnerable. In addition, because the periprosthetic muscle groups of middle-aged and elderly people are degenerated and unresponsive, they cannot effectively counteract the harmful stresses in the hip, plus the hip is subjected to greater stress and complex and variable local stresses, so fractures can occur without much violence, such as slipping on flat ground, falling from bed or sudden twisting of lower limbs, even in the absence of obvious trauma! Fractures of the femoral neck in young adults, on the other hand, are often caused by serious injuries such as car accidents or falls from height. If the fracture occurs gradually due to excessive heavy work or walking, it is called fatigue fracture.
II. Clinical manifestations
1.Symptoms
When an elderly person complains of hip pain after a fall and is afraid to stand and walk, or when a middle-aged person suffers from hip pain and limited activity after a serious trauma, the possibility of femoral neck fracture should be thought of. Some small fractures may not have clinical symptoms in the early stage, and it is necessary to perform CT review for patients suspected of having such femoral neck fractures.
2. Physical signs
(1) Deformity: the affected limb has mild hip flexion and knee flexion and external rotation deformity, as shown in the figure.
(2) Pain: In addition to spontaneous pain in the hip, the pain is more obvious when moving the affected limb. The hip is also painful when the affected limb is tapped on the heel or the outer thigh, and there is often pressure pain at the mid-point of the groin.
(3) Swelling: most of the femoral neck fractures are intracapsular fractures, which do not bleed much after fracture and are surrounded by extra-articular thick muscles, so it is not easy to see obvious local swelling in appearance.
(4) Functional impairment: Patients with displaced fractures cannot sit up or stand after the injury, but there are some cases of nondisplaced linear fractures or insertion fractures that can still walk or ride a bicycle after the injury. Special care should be taken in these patients not to turn a nondisplaced stable fracture into a displaced unstable fracture by missing the diagnosis. In displaced fractures, the distal end is displaced upward by traction of the muscle groups, and thus a shortening of the affected limb is noted.
III. Treatment
1. Conservative treatment.
For elderly patients who cannot be treated surgically due to the combination of other serious underlying diseases, conservative treatment can be chosen. The patient brakes the affected limb, wears nail shoes to maintain the functional position of the affected limb, and resets the fracture manually in order to slowly heal the fractured end by itself. However, many serious complications may occur as a result of long-term bed rest. Eventually, the fracture may still be difficult to heal, and the patient may not be able to move to the ground for a long time, resulting in complications such as lung infection, pressure sores, phlebitis, deep vein thrombosis in the lower limbs, disuse muscle atrophy and osteoporosis, which can be life-threatening in severe cases.
2.Artificial joint replacement.
Middle-aged and elderly patients, patients who are feasible for surgical treatment can be considered for artificial joint replacement surgery treatment. The surgery is not very traumatic, and the patient can go down to the ground early after the surgery (generally 3 days after surgery) and functional exercise, basically preserving the function of the whole hip joint, and following the doctor’s instruction for functional exercise after the surgery, which is conducive to the recovery of elderly patients from injuries and diseases as soon as possible, effectively avoiding the complications of conservative treatment and reducing the burden on families and society. However, young patients must face the problem of re-operation due to the insufficient service life of the prosthesis (20-30 years).
3. Surgical repositioning and internal fixation treatment.
Another treatment method for femoral neck fracture is internal fixation by manipulative repositioning, which is suitable for young and middle-aged patients. As long as there is a satisfactory reset, fix the fracture end with internal fixation equipment, most of the internal fixation methods can obtain 80% to 90% of the healing rate, and only 5% to 10% of the non-healing cases require surgery later, but this method may still occur femoral head necrosis, about 1/3 of the cases need to re-operation or artificial hip replacement treatment. The method of early non-invasive reset, reasonable multiple nail fixation, is conducive to early recovery.
IV. Prevention
Elderly people at risk should pay attention to the prevention of fall trauma and active anti-osteoporosis treatment to maintain bone health; middle-aged and young people should avoid serious trauma and have self-protection to avoid fracture in case of danger.