High Yield Topics

Femoral Neck Fracture

By admin


Ovid: 5-Minute Orthopaedic Consult

Editors: Frassica, Frank J.; Sponseller, Paul D.; Wilckens, John H.
Title: 5-Minute Orthopaedic Consult, 2nd Edition
> Table of Contents > Femoral Neck Fracture

Femoral Neck Fracture
Daniel L. Miller BS
Tung B. Le MD
Basics
Description
  • Femoral neck fracture is the most common cause of a “broken hip.”
  • The femoral neck is the intracapsular
    portion of the proximal femur between the femoral head and the lesser
    and greater trochanters.
  • Femoral neck fractures are most common in
    elderly patients, although younger patients involved in high-energy
    trauma also are affected.
  • In the elderly, immobilization from these
    injuries can lead to secondary cardiopulmonary complications, severe
    morbidity, and mortality.
  • Classification (4):
    • Stable (nondisplaced fracture): May be impacted or incomplete
    • Unstable: Complete and displaced fracture
Epidemiology
Incidence
  • The occurrence of femoral neck fractures per 100,000 person years is 27.7 in males and ~63.3 in females (1,2).
  • Rates of fracture have leveled off, perhaps secondary to the use of antiresorptive agents (3).
Prevalence
  • In the young population, more males than females sustain this injury.
  • In elderly patients, females are affected 2–3 times more often than are males (3).
Risk Factors
  • Osteoporosis, which is the major risk factor for femoral neck fractures in the elderly
  • Factors that increase the risk of falling, such as an unsteady gait
  • Female gender (postmenopausal)
  • Physical inactivity
  • Caucasian race
Etiology
  • In patients <50 years old, femoral
    neck fractures often are the result of high-energy trauma with a direct
    force along the femoral shafts.
  • In the older population, these fractures are caused by low-energy trauma, such as a fall from a standing height.
Associated Conditions
  • Osteoporosis
  • Conditions that increase the risk of a fall:
    • Poor vision and macular degeneration
    • Urinary incontinence or frequency
    • Poor balance
    • Polypharmacy
    • Syncope
    • Use of benzodiazepams
Diagnosis
Signs and Symptoms
  • Patients have severe pain in the groin area and, with unstable fractures, the leg is shortened.
  • The patient may be unable to ambulate.
  • Patients hold their hips slightly flexed and externally rotated.
  • Pain is worsened with attempted ROM or axial loading.
  • Patients with stable fractures will not have shortening or rotational deformity.
History
A history of pain in the hip before the fracture is worrisome for metastatic disease.
Physical Exam
  • Perform an examination for pain on ROM, especially internal rotation.
  • With unstable fractures, the leg often is rotated externally and shortened.
  • Examine the pelvis with direct palpation and radiography to exclude a concomitant pelvic fracture.
  • Active straight-leg raise will provoke pain.
Tests
Lab
Preoperative laboratory tests, blood type and screen,
chest radiographs, and an electrocardiogram are needed at time of
admission.
Imaging
  • Radiography:
    • AP pelvic radiographs
    • AP and cross-table lateral radiographs of the affected hip and femur
  • MRI to diagnose occult femoral neck fractures in patients with negative radiographs
  • Dedicated hip CT is useful for patients with ipsilateral femoral shaft fractures.
Pathological Findings
Elderly patients may have comminution of the femoral neck, especially in the subcapital region.
Differential Diagnosis
  • When a fracture is not obvious on the
    plain films of a patient with hip pain secondary to trauma, an occult
    (nondisplaced) fracture should be suspected.
  • Other causes of hip pain include:
    • Pelvic fracture
    • Intertrochanteric fracture
    • Infection
    • Greater trochanter bursitis
    • Metastatic disease
Treatment
General Measures
  • Stable fractures should be stabilized internally with cannulated lag screws.
  • Treatment of unstable femoral neck fractures is controversial (5):
    • In general, displaced fractures in young
      (<50 years old), active patients should be reduced by closed or open
      means and stabilized internally with screws.
    • Because of the high rate of osteonecrosis
      of the femoral head, fractures in young patients (<50 years old) are
      considered orthopaedic emergencies.
    • In the multiply injured patient,
      attention to other organ systems and concurrent care with other members
      of the trauma team are essential.
    • In older (physiologic age >70 years)
      patients, more sedentary patients, or in those with Paget disease or
      neurologic diseases such as Parkinson disease or hemiplegia, partial or
      total arthroplasty is the treatment of choice.
  • In older patients with isolated femoral neck injuries, rapid medical consultation to optimize surgical outcomes is important.
  • Delayed treatment of femoral neck fractures in elderly patients can lead to major cardiopulmonary complications.
Activity
  • Patients are at bed rest.
  • Use of traction does not give pain relief and can cause skin complications.
Nursing
  • Avoid decubitus ulcers of the buttock and heels.
    • Turn the patient frequently.
    • Use heel protectors and specialized beds.
  • Avoid delirium in the elderly by:
    • Constant reorientation of the patient
    • Appropriate use of calendars and clocks
    • Avoidance of medicines that can provoke delirium (e.g., long-acting benzodiazepams)
Special Therapy
Physical Therapy
  • Begin physical therapy the day after surgery.
  • Elderly patients are allowed to bear weight as tolerated after fracture repair.
  • In younger patients, weightbearing is restricted until the fracture heals (6).
Medication
  • Analgesics
  • In the elderly, one should observe for a change in mental status and constipation with the use of narcotic analgesics.
  • Young patients need adequate narcotic doses to facilitate rehabilitation.

P.127


Surgery
  • The patient is placed supine on a
    fracture table, and the fracture is visualized through a small incision
    or percutaneously under fluoroscopy; alternatively, a lateral approach
    on a radiolucent table may be used.
    • In young patients or those with stable fractures:
      • 3 screws are placed with the aid of the image intensifier.
      • Screws should be spread out in a triangular pattern.
      • Screws must be inserted deeply into the subchondral bone of the femoral head.
    • Unstable fracture patterns, in which the fracture line is closer to the trochanters (basicervical fractures):
      • A hip screw and side plate are required.
      • Precise reduction of the fracture is crucial to a good outcome (7).
    • 6–9% of patients with femoral shaft
      fractures have an ipsilateral femoral neck fracture; fixation of the
      femoral neck takes precedence over that of the shaft (8).
  • Prosthetic replacement can be done
    through a lateral or posterior approach with uncemented or cemented
    devices, depending on bone geometry and surgeon comfort.
    • In minimally active patients, hemiarthroplasty (replacing only the femoral head and neck) is performed.
    • In active patients or those with
      pre-existing osteoarthritis, consider total hip replacement
      (replacement of both the acetabulum and the femoral head and neck) (9).
Follow-up
Prognosis
  • The mortality rate in the elderly population ranges from 4–31% at 30 days after hip fracture (10).
  • This rate is highest during the first 6 months and in patients with multiple medical problems or prolonged immobilization.
Complications
  • Osteonecrosis of the femoral head
  • Nonunion or malunion of bone
  • Prosthetic dislocation or loosening
  • Persistent pain
  • Infection
  • Cardiopulmonary complications
  • Postoperative delirium
  • DVT
Patient Monitoring
  • Intensive cardiovascular monitoring in
    multiply injured patients or in patients with multiple medical problems
    should be instituted during the perioperative period.
  • In patients with internally stabilized fractures, radiographs are obtained once a month until union is achieved.
  • In patients who have undergone arthroplasty, radiographs are obtained at 3 and 12 months.
References
1. Cummings
SR, Rubin SM, Black D. The future of hip fractures in the United
States. Numbers, costs, and potential effects of postmenopausal
estrogen. Clin Orthop Relat Res 1990;252:163–166.
2. Hedlund
R, Lindgren U, Ahlbom A. Age- and sex-specific incidence of femoral
neck and trochanteric fractures. An analysis based on 20,538 fractures
in Stockholm County, Sweden, 1972–1981. Clin Orthop Relat Res 1987;222:132–139.
3. Chang
KP, Center JR, Nguyen TV, et al. Incidence of hip and other
osteoporotic fractures in elderly men and women: Dubbo Osteoporosis
Epidemiology Study. J Bone Miner Res 2004;19:532–536.
4. Rodriguez-Merchan EC. In situ fixation of nondisplaced intracapsular fractures of the proximal femur. Clin Orthop Relat Res 2002;399:42–51.
5. Bhandari
M, Devereaux PJ, Swiontkowski MF, et al. Internal fixation compared
with arthroplasty for displaced fractures of the femoral neck. A
meta-analysis. J Bone Joint Surg 2003;85A:1673–1681.
6. Koval
KJ, Sala DA, Kummer FJ, et al. Postoperative weight-bearing after a
fracture of the femoral neck or an intertrochanteric fracture. J Bone Joint Surg 1998;80A:352–356.
7. Haidukewych
GJ, Rothwell WS, Jacofsky DJ, et al. Operative treatment of femoral
neck fractures in patients between the ages of fifteen and fifty years.
J Bone Joint Surg 2004;86A: 1711–1716.
8. Watson JT, Moed BR. Ipsilateral femoral neck and shaft fractures: complications and their treatment. Clin Orthop Relat Res 2002;399:78–86.
9. Blomfeldt
R, Tornkvist H, Ponzer S, et al. Comparison of internal fixation with
total hip replacement for displaced femoral neck fractures. Randomized,
controlled trial performed at four years. J Bone Joint Surg 2005;87A:1680–1688.
10. Roberts
SE, Goldacre MJ. Time trends and demography of mortality after
fractured neck of femur in an English population, 1968–98: database
study. Br Med J 2003;327:771–775.
Miscellaneous
Codes
ICD9-CM
820.8 Femoral neck fracture
Patient Teaching
  • Patients should be informed about the
    high incidence of osteonecrosis (also known as “AVN”) of the femoral
    head associated with this type of injury.
  • The risk of osteonecrosis depends on the type of injury and on the timing of diagnosis and treatment.
  • A multiply injured patient has a higher risk of osteonecrosis than does a patient with an isolated injury.
Prevention
  • In the elderly:
    • Calcium, vitamin D, bisphosphonates, and
      physical therapy should be used to reduce osteoporosis and minimize the
      risk of femoral neck fracture.
    • Fall prevention should be emphasized.
    • Ambulatory aids, such as walkers or canes to increase stability, are helpful.
    • Home modification strategies, such as handrails or single level homes, should be considered.
    • Externally worn hip protectors may decrease the incidence or fracture.
FAQ
Q: How likely is an elderly person to get back to the previous level of ambulation?
A: ~1/2; the other 1/2 require more aids to ambulate.

Q: What is the outcome of unstable fractures in the elderly treated with internal fixation?
A:
Patients treated with internal fixation may heal their fractures and
save their native hip. However, risk exists that either the fracture
will not heal or AVN will develop. More patients with internal fixation
require a 2nd surgery than do those with replacement.

Continue Reading
You might also like More from author

This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Accept Read More