Hip Anatomy

Definition: Fracture of the proximal femur, through the neck, which connects the femoral head with the femoral shaft


  • Elderly: Low energy fall is the most common cause
  • Young: High energy trauma

Epidemiology (Skinner 2014, Egol 2015)

  • Estimated 6.3 mil hip fractures worldwide by 2050
  • 50% of hip fractures in US involve the femoral neck
  • 80% women, 20% men
  • Old>>Young
  • White>Black

Fracture Classification Systems

  • Pauwel – based on angle fracture forms with horizontal plane
  • Garden – based on degree of valgus displacement
    • Type I – Incomplete/Valgus Impacted
    • Type II – Complete and nondisplaced on AP and lateral views
    • Type III – Complete with partial displacement
    • Type IV – Complete displaced
  • For ED purposes, can simply classify as “displaced” or “nondisplaced”

Pauwels’ Classification (intranet.tdmu.edu.ua)

Short and Externally Rotated (gurgaonkneeandshoulderclinic.com)

Physical Exam

  • Examine the patient from head to toe looking for other areas of trauma
  • Displaced fracture
    • Leg shortened, externally rotated
    • Non ambulatory
    • Typically in considerable amount of pain in hip and/or groin area
  • Nondisplaced fracture
    • No deformity
    • Patient may be ambulatory
    • May complain of vague pain in hip, groin, buttocks, thigh, knee
  • Perform a complete neurovascular exam focusing on distal pulses and sensation

Base of Right Femoral Neck Fracture (Case courtesy of Dr M Osama Yonso, Radiopaedia.org. From the case rID: 18409)

Diagnostic Imaging:

  • Required radiograph views
    • AP pelvis, AP and cross table lateral hip, AP/lateral femur
  • Frog leg view contraindicated – may cause worsening displacement or displace a nondisplaced fracture
  • Evaluation of X-Rays 
    • Look for disruption along Shenton’s Line
    • Evaluate the neck-shaft angle (normal is 120-130 degrees)
  • If X-rays negative, consider advanced imaging for occult fracture
    • Up to 10% of hip fractures will be missed on X-ray
    • Approximately 2% of occult hip fractures on X-ray and CT are identified on MRI (Hakkarinen 2012)
    • MRI currently gold standard but new research suggests CT may be just as good (Thomas 2016)

Hip Fracture Imaging Algorithm

ED Management

  • Analgesia
    • Systemic analgesia. Typically in form of parenteral opiate
    • Nerve Block
      • Consider ultrasound guided femoral nerve block and/or fascia iliaca compartment block
      • Advantage: can provide significant reduction in pain without systemic effects often seen with opiates (i.e respiratory depression, nausea, hypotension)
  • Medical Assessment
    • Consider cause of fall
      • Mechanical fall leading to trauma vs. syncope leading to fall
      • Liberal use of EKG and tests evaluating for syncope beneficial
    • Consider associated conditions
      • Systemic infection
      • Dehydration
      • Rhabdomyolysis (especially if found down for unknown period of time)
  • Assess for other injuries
    • Consider head and neck trauma in all patients
    • Consider other orthopedic injuries
  • Orthopedic surgery consultation for operative management

Femoral Neck Blood Supply (nutritionreview.org)


  • One year mortality 20-30% (Brauer 2009)
  • Increased mortality risk has been associated with
    • Male sex
    • Age >85
    • Higher ASA classification
    • Delay to surgery and early mobilization
  • Complications
    • Infection, Thromboembolism, Nonunion
    • Avascular necrosis (AVN)
      • Due to location of blood supply, femoral neck fractures have higher incidence of AVN than intertrochanteric fractures
      • 5-15% of nondisplaced fractures develop AVN (Egol)
      • Incidence of AVN increases with degree of displacement

Take Home Points:

  • Investigate the cause of trauma in all patients presenting with femoral neck fractures (mechanical vs syncope)
  • Assess for concomitant injuries, especially in the elderly patient
  • Occult fractures are common – proceed to advanced imaging if index of suspicion high
  • Provide adequate pain control and consider regional nerve block

Read More

The Ultrasound Podcast: Episode 24 – Femoral Nerve

Steele M, Stubbs AM. Hip and Femur Injuries. In: Tintinalli JE, Stapczynski J, Ma O,

Yealy DM, Meckler GD, Cline DM. eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 8e New York, NY: McGraw-Hill; 2016.

Smith WR et al. Chapter 2. Musculoskeletal Trauma Surgery. In: Skinner HB, McMahon PJ. eds. Current Diagnosis & Treatment in Orthopedics, 5e New York, NY: McGraw-Hill; 2014.


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

Egol, KA et al.  Chapter 29. Femoral Neck Fractures. Handbook of Fractures. 2015. Link

Hakkarinen, DK. Magnetic Resonance Imaging Identifies Occult Hip Fractures Missed by 64-slice Computed Tomography. J Emerg Med. 2012; 43(2) 303-7. PMID: 22459594

Schnell S et al. The 1-Year Mortality of Patients Treated in a Hip Fracture Program for Elders. Geriatr Orthop Surg Rehabil 2010: 1(1): 6-14. PMID: 23569656

Skinner, Harry B., and Patrick J. McMahon. Current Diagnosis & Treatment in Orthopedics. McGraw-Hill Education, 2014.

Thomas RW et al. The Validity of Investigating Occult Hip Fractures Using Multidetector CT. Br J Rad 89.1060 (2016). PMID: 26838948