Intertrochanteric Fractures

Neck of Femur Classification (http://www.oxfordmedicaleducation.com/)

Definition: Fracture in the proximal femur, between the lesser trochanter and greater trochanter.

Mechanism 

• Elderly: > 90% are from a low energy fall (Egol 2010)
• Young: Typically a high-energy trauma, such as a motor-vehicle accident or fall from a height

Epidemiology

• Intertrochanteric fractures account for about 50% of proximal femur fractures (Egol 2010)
• Female to male ratio is 3:1, likely due to bone density changes in post-menopausal women (UptoDate 2017)

Hip Fracture Physical Exam (image.wikifoundry.com)

Physical Exam

• Non-displaced fracture
  • Patients may have minimal pain
  • Patients may be ambulatory despite presence of fracture
• Displaced fractures
  • Pain in lower extremity
  • Non-ambulatory
  • Affected leg is shortened and externally rotated

Fracture Types

• Stable vs Unstable
  • Stable
    • Posteromedial cortex is intact or minimal comminution
    • When load is applied, intact cortex will prevent external rotation and varus displacement
  • Unstable
    • Disruption of posteromedial cortex
    • Comminution of posteromedial cortex
    • Subtrochanteric extension
    • Reverse obliquity fracture: fracture line proximally from medial cortex distally to lateral cortex
• Occult Fracture
• • Fracture not visible on plain X-rays
  • Requires advanced imaging to diagnose

Evans Classification (https://image.slidesharecdn.com)

Intertrochanteric Fracture AP X-ray (Case courtesy of Dr M Osama Yonso, Radiopaedia.org. From the case rID: 16317)

Diagnostic Imaging

• X-Ray
  • Required views: AP Pelvis, AP and cross table lateral Hip, AP Femur
  • Will demonstrate fracture between the greater and lesser trochanter, with/out extension into the subtrochanteric region
  • Occult Fractures
    • X-rays will miss about 10% of hip fractures
    • Of all hip fractures, 8% are identified by CT scan but missed on X-ray
    • About 2% of all hip fractures are missed on X-rays and CT scan, but seen on MRI
• Advanced Imaging (CT and MRI)
  • Consider if X-Rays are negative but patient is unable to bear weight or physical exam is concerning for fracture

Hip Fracture Imaging Algorithm

ED Management

• Analgesia
  • Femoral nerve block
    • Pros
      • Easy to perform by landmark or ultrasound technique
      • Provides analgesia without systemic effects
    • Cons: Does not provide analgesia to lateral thigh
• • Fascia iliaca compartment block
    • Pros
      • Injection away from nerve and artery reducing complications
      • Provides analgesia to lateral thigh
    • Cons: Requires larger volume of anesthetic
• • Systemic analgesia typically provided with opiates/opioids
• Assess for secondary injuries
  • Assess for additional fractures
  • Consider head and cervical spine trauma in all patients
  • Consider complications from fall (i.e. prolonged immobility on ground)
• Investigate cause of fall (i.e. mechanical fall vs. syncope)
• Monitor blood loss
  • About 40% of patients with hip fractures require blood transfusions (Desai 2014)
  • Patients with intertrochanteric fractures are twice as likely to need blood transfusion as those with a femoral neck fracture
• Non-operative
  • Pursued for patients at very high-risk of perioperative mortality or non-ambulatory at baseline
  • Non-weight bearing
  • Goal: Early bed to chair mobilization to prevent complications such as pneumonia, VTEs, ulcers
• Operative
  • Stable: Sliding hip screw
  • Unstable: Intramedullary hip screw or arthroplasty

Prognosis

• 1 year mortality: 20-30% (Brauer 2009)
• Mortality higher than in femoral neck fracture (Haentjens 2007)
• Increased mortality associated with
  • Age over 85
  • Pre-existing medical conditions or ASA classification III and IV
  • Male
  • Operative delay for more than 2 days
• Low rates of non-union and malunion, because of extensive blood supply

Take Home Points

• Occult fractures are common. A negative X-ray with a high clinical suspicion should be followed by a CT and/or MRI
• Do not forget to assess for secondary injury and monitor blood loss
• Provide adequate analgesia with a regional nerve block or opioids
• It is important to diagnose hip fractures early because there is a high mortality rate with delay in operative management

Read More

Orthobullets: Intertrochanteric Fractures

UptoDate: Hip Fractures in Adults

Highland EM Ultrasound: Femoral Block

Ultrasound Podcast: Lower Extremity Nerve Block Mastery with Mike Stone!

References

Egol KA et al. Handbook of Fractures. Lippincott Williams & Wilkins; 2010. Link

Desai SJ et al. Factors affecting transfusion requirement after hip fracture: can we reduce the need for blood?. Can J Surg. 2014;57(5):342-8. PMID 25265109

Brauer CA et al. Incidence and mortality of hip fractures in the United States. JAMA. 2009;302(14):1573-9. PMID 19826027

Haentjens P et al. Survival and functional outcome according to hip fracture type: a one-year prospective cohort study in elderly women with an intertrochanteric or femoral neck fracture. Bone. 2007;41(6):958-64. PMID 17913614