Femoral Neck Fractures

1
Femoral Neck Fractures
2
Anatomy

• Physeal closure age 16
• Neck-shaft angle
• 130 7
• Anteversion
• 10 7
• Calcar Femorale
• Posteromedial
• dense plate of bone

3
Blood Supply

• Lateral epiphysel artery
• terminal branch MFC artery
• predominant blood supply to weight bearing dome
  of head
• Artery of ligamentum teres
• from obturator artery
• supplies anteroinferior head
• Lateral femoral circumflex a.
• less contribution than MFC

4
Blood Supply

• Greater fracture displacement greater risk of
  vascular disruption to femoral head
• revascularization of the head
• intact vessels
• vascular ingrowth across fracture site
• importance of quality of reduction
• metaphyseal vessels

5
Epidemiology

• 250,000 Hip fractures annually
• Expected to double by 2050
• At risk populations
• Elderly poor balance vision, osteoporosis,
  inactivity, medications, malnutrition
• incidence doubles with each decade beyond age 50
• higher in white population
• Other factors smokers, small body size,
  excessive caffeine
• Young high energy trauma

6
Classification

• Pauwels 1935
• Angle describes vertical shear vector

7
Classification

• Garden 1961
• I Valgus impacted or
• incomplete
• II Complete
• Non-displaced
• III Complete
• Partial displacement
• IV Complete
• Full displacement
• Portends risk of AVN and Nonunion

I
II
III
IV
8
Classification

• Functional Classification
• Stable
• Impacted (Garden I)
• Non-displaced (Garden II)
• Unstable
• Displaced (Garden III and IV)

9
Treatment

• Goals
• Improve outcome over natural history
• Minimize risks and avoid complications
• Return to pre-injury level of function
• Provide cost-effective treatment

10
Treatment

• Options
• Non-operative
• very limited role
• Activity modification
• Skeletal traction
• Operative
• ORIF
• Hemiarthroplasty
• Total Hip Replacement

11
TreatmentDecision Making Variables

• Patient Characteristics
• Young (arbitrary physiologic age lt 65)
• High energy injuries
• Often multi-trauma
• High Pauwels Angle (vertical shear pattern)
• Elderly
• Lower energy injury
• Comorbidities
• Pre-existing hip disease
• Fracture Characteristics
• Stable
• Unstable

12
TreatmentYoung Patients(Arbitrary physiologic
age lt 65)

• Non-displaced fractures
• At risk for secondary displacement
• Urgent ORIF recommended
• Displaced fractures
• Patients native femoral head best
• AVN related to duration and degree of
  displacement
• Irreversible cell death after 6-12 hours
• Emergent ORIF recommended

13
TreatmentElderly Patients

• Operative vs. Non-operative
• Displaced fractures
• Unacceptable rates of mortality, morbidity, and
  poor outcome with non-operative treatment Koval
  1994
• Non-displaced fractures
• Unpredictable risk of secondary displacement
• AVN rate 2X
• Standard of care is operative for all femoral
  neck fractures
• Non-operative tx may have developing role in
  select patients with impacted/ non-displaced
  fractures Raaymakers 2001

14
TreatmentPre-operative Considerations

• Regional vs. General Anesthesia
• Mortality / long term outcome
• No Difference
• Regional
• Lower DVT, PE, pneumonia, resp depression, and
  transfusion rates
• Further investigation required for definitive
  answer

15
TreatmentPre-operative Considerations

• Surgical Timing
• Surgical delay for medical clearance in
  relatively healthy patients probably not
  warranted
• Increased mortality, complications, length of
  stay
• Surgical delay up to 72 hours for medical
  stabilization warranted in unhealthy patients

16
Hemi
ORIF
THR
17
Non-displaced Fractures

• ORIF standard of care
• Predictable healing
• Nonunion lt 5
• Minimal complications
• AVN lt 8
• Infection lt 5
• Relatively quick procedure
• Minimal blood loss
• Early mobilization
• Unrestricted weight bearing with assistive device
  PRN

18
Open Reduction or Closed Reduction?

• Open reduction can be considered for any
  displaced femoral neck fractures that are treated
  with reduction and internal fixation
• Open reduction is indicated after an attempt at
  gentle closed reduction results in a non-anatomic
  reduction
• Primary open reduction is preferred in young
  patients with a displaced femoral neck fracture

19
Approach For Open Reduction

• Smith-Peterson
• Anterior approach
• Best for transcervical and subcapitol fractures
• Fixation is performed through a second approach

20
Approach For Open Reduction

• Watson-Jones
• Anteriolateral exposure
• Best for basalar neck and IT patterns
• Allows placement of sliding hip screw through
  same incision

21
What Reduction Is Acceptable?

• Ideal reduction is Anatomic
• Acceptable lt 15º valgus lt 10º AP angulation
• Any varus is unacceptable
• Fixation Multiple screws in parallel
• No advantage to gt 3 screws
• Uniform compression across fracture
• In-situ pin impacted fractures
• ? AVN with disimpaction Crawford
  1960
• Fixation most dependent on bone density

22
Screw Fixation

• Screw location
• Avoid posterior/ superior quadrant
• Blood supply
• Cut-out
• Biomechanical advantage to inferior/ calcar screw
  
• 
  Booth 1998

23
Sliding Compression Screw Fixation

• Compression Hip Screws
• Sacrifices large amount of bone
• May injure blood supply
• Biomechanically superior in cadavers
• Anti-rotation screw often needed
• Increased cost and operative time
• No clinical advantage over parallel screws
• May have role in high energy/ vertical shear
  fractures

24
Intracapsular Hematoma

• incidence- 75 have some intracapsular
  pressure
• no difference displaced/nondisplaced
• sensitive to leg position
• extension internal rotation bad
• animal models intracapsular pressure
  perfusion
• Theoretical benefit with NO clinical proof
• but it doesnt hurt

25
Case Example 42 yo male, MVC
26
Open reduction via Smith-Pete approach, screw
fixation placed through separate incision
27
Displaced FracturesHemiarthroplasty vs. ORIF

• ORIF is an option in elderly
• Surgical emergency in young patients
• Complications
• Nonunion 10 -33
• AVN 15 33
• AVN related to displacement
• Early ORIF no benefit
• Loss of reduction / fixation failure 16

28
Displaced FracturesHemiarthroplasty vs. ORIF

• Hemi associated with
• Lower reoperation rate (6-18 vs. 20-36)
• Improved functional scores
• Less pain
• More cost-effective
• Slightly increased short term mortality
• Literature supports hemiarthroplasty for
  displaced fractures
  Lu-yao JBJS 1994
• 
  Iorio CORR 2001

29
HemiarthroplastyUnipolar vs. Bipolar

• Bipolar theoretical advantages
• Lower dislocation rate
• Less acetabular wear/ protrusio
• Less Pain
• More motion

30
HemiarthroplastyUnipolar vs. Bipolar

• Bipolar
• Disadvantages
• Cost
• Dislocation often requires open reduction
• Loss of motion interface (effectively unipolar)
• Polyethylene wear/ osteolysis not yet studied for
  Bipolars

31
HemiarthroplastyUnipolar vs. Bipolar

• Complications / Mortality / Length of stay
• No Difference
• Hip Scores / Functional Outcomes
• No significant difference
• Bipolar slightly better walking speeds, motion,
  pain
• Revision rates
• Unipolar 20 vs. Bipolar 10 (7 years)
• Unipolar more cost-effective
• Literature supports use of either implant

32
HemiarthroplastyCemented vs. Non-cemented

• Cement (PMMA)
• Improved mobility, function, walking aids
• Most studies show no difference in morbidity /
  mortality
• Sudden Intra-op cardiac death risk slightly
  increased
• 1 cemented hemi for fx vs. 0.015 for elective
  arthroplasty
• Non-cemented (Press-fit)
• Pain / Loosening higher
• Intra-op fracture (theoretical)

33
HemiarthroplastyCemented vs. Non-cemented

• Conclusion
• Cement gives better results
• Function
• Mobility
• Implant Stability
• Pain
• Cost-effective
• Low risk of sudden cardiac death
• Use cement with caution

34
TreatmentPre-operative Considerations

• Surgical Approach
• Posterior approach to hip
• 60 higher short-term mortality vs. anterior
• Dislocation rate
• No significant difference Lu-Yao
  JBJS 1994

35
Total Hip Replacement

• Dislocation rates
• Hemi 2-3 vs. THR 11 (short term)
• 2.5 THR recurrent dislocation
  Cabanela Orthop 1999
• Reoperation
• THR 4 vs. Hemi 6-18
• DVT / PE / Mortality
• no difference
• Pain / Function / Survivorship /
  Cost-effectiveness
• THR better than Hemi
  Lu Yao JBJS 1994
• 
  Iorio CORR 2001

36
ORIF or Replacement?
Keating et al OTA 2002

• Prospective, randomized study ORIF vs. cemented
  bipolar hemi vs. THA
• ambulatory patients gt 60 years of age
• 37 fixation failure (AVN/nonunion)
• similar dislocation rate hemi vs. THA (3)
• ORIF 8X more likely to require revision surgery
  than hemi and 5X more likely than THA
• THA group best functional outcome

37
Stress Fractures

• Patient population
• Females 410 times more common
• Amenorrhea / eating disorders common
• Femoral BMD average 10 less than control
  subjects
• Hormone deficiency
• Recent increase in athletic activity
• Frequency, intensity, or duration
• Distance runners most common

38
Stress Fractures

• Clinical Presentation
• Activity / weight bearing related
• Anterior groin pain
• Limited ROM at extremes
• Antalgic gait
• Must evaluate back, knee, contralateral hip

39
Stress Fractures

• Imaging
• Plain Radiographs
• Negative in up to 66
• Bone Scan
• Sensitivity 93-100
• Specificity 76-95
• MRI
• 100 sensitivity / specificity
• Also Differentiates synovitis, tendon/ muscle
  injuries, neoplasm, AVN, transient osteoporosis
  of hip

40
Stress Fractures

• Classification
• Compression sided
• Callus / fracture at inferior aspect femoral neck
• Tension sided
• Callus / fracture at superior aspect femoral neck
• Displaced

41
Stress FracturesTreatment

• Compression sided
• Fracture line extends lt 50 across neck
• stable
• Tx Activity / weight bearing modification
• Fracture line extends gt50 across neck
• Potentially unstable with risk for displacement
• Tx Emergent ORIF
• Tension sided
• Unstable
• Tx Emergent ORIF
• Displaced
• Tx Emergent ORIF

42
Stress FracturesComplications

• Tension sided and Compression sided fxs (gt50)
  treated non-operatively
• Varus malunion
• Displacement
• 30-60 complication rate
• AVN 42
• Delayed union 9
• Nonunion 9

43
Femoral Neck Nonunion

• Definition not healed by one year
• 0-5 in Non-displaced fractures
• 9-35 in Displaced fractures
• Increased incidence with
• Posterior comminution
• Initial displacement
• Inadequate reduction
• Non-compressive fixation

44
Femoral NeckNonunion

• Clinical presentation
• Groin or buttock pain
• Activity / weight bearing related
• Symptoms
• more severe / occur earlier than AVN
• Imaging
• Radiographs lucent zones
• CT lack of healing
• Bone Scan high uptake
• MRI assess femoral head viability

45
Femoral NeckNonunion

• Treatment
• Elderly patients
• Arthroplasty
• Results typically not as good as primary elective
  arthroplasty
• Girdlestone Resection Arthroplasty
• Limited indications
• deep infection?

46
Femoral NeckNonunion

• Young patients
• (must have viable femoral head)
• Varus alignment or limb shortened
• Valgus-producing osteotomy
• Normal alignment
• Bone graft / muscle-pedicle graft
• Repeat ORIF

47
Osteonecrosis (AVN)Femoral Neck Fractures

• 5-8 Non-displaced fractures
• 20-45 Displaced fractures
• Increased incidence with
• INADEQUATE REDUCTION
• Delayed reduction
• Initial displacement
• associated hip dislocation
• ?Sliding hip screw / plate devices

48
Osteonecrosis (AVN)Femoral Neck Fractures

• Clinical presentation
• Groin / buttock / proximal thigh pain
• May not limit function
• Onset usually later than nonunion
• Imaging
• Plain radiographs segmental collapse /
  arthritis
• Bone Scan cold spots
• MRI diagnostic

49
Osteonecrosis (AVN)Femoral Neck Fractures

• Treatment
• Elderly patients
• Only 30-37 patients require reoperation
• Arthroplasty
• Results not as good as primary elective
  arthroplasty
• Girdlestone Resection Arthroplasty
• Limited indications

50
Osteonecrosis (AVN)Femoral Neck Fractures

• Treatment
• Young Patients
• NO good option exists
• Proximal Osteotomy
• Less than 50 head collapse
• Arthroplasty
• Significant early failure
• Arthrodesis
• Significant functional limitations
• Prevention is the Key

51
Femoral Neck FracturesComplications

• Failure of Fixation
• Inadequate / unstable reduction
• Poor bone quality
• Poor choice of implant
• Treatment
• Elderly Arthroplasty
• Young Repeat ORIF
• Valgus-producing osteotomy
• Arthroplasty

52
Femoral Neck FracturesComplications

• Post-traumatic arthrosis
• Joint penetration with hardware
• AVN related
• Blood Transfusions
• THR gt Hemi gt ORIF
• Increased rate of post-op infection
• DVT / PE
• Multiple prophylactic regimens exist
• Low dose subcutaneous heparin not effective

53
Femoral Neck FracturesComplications

• One-year mortality 14-50
• Increased risk
• Medical comorbidities
• Surgical delay gt 3 days
• Institutionalized / demented patient
• Arthroplasty (short term / 3 months)
• Posterior approach to hip