Intracapsular Femoral Neck Fractures ORIF

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Intracapsular Femoral Neck Fractures -ORIF

January 19, 2008 Kyle Jeray Greenville Hospital
System
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OBJECTIVES

• ANATOMY
• BONY
• VASCULAR
• CLASSIFICATION
• EXPOSURES
• FIXATION TECHNIQUES
• SUMMARY

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Femoral Neck Fractures-Bimodal Distribution

• Elderly
• Low energy
• Falls
• Often impacted
• Younger
• High energy
• MVC
• Impaction is unusual

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Vascular Anatomy

• Terminal Branches
• - Lateral epiphyseal artery
• - Inferior metaphyseal artery
• - Ligamentum teres artery

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Femoral Head Blood Supply

• Femoral head blood supply is primarily from
  medial femoral circumflex a.
• Artery enters posteriorly
• No significant blood supply is carried to the
  femoral head from the anterior hip capsule

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Classification

• GARDEN
• USEFUL WITH ELDERLY
• PAUWELS
• MORE USEFUL WITH YOUNG

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Arthroplasty vs. ORIF
Old patients should get a Hemi.
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How Old is Old?

• Chronologic age vs. physiologic age
• Many older patients more active and have higher
  functional expectations
• The real issue is bone density

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Singh Index

• Loss of trabeculae with increasing osteoporosis
• In advanced stages the femoral neck is hollow

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Consequence of Poor Bone Quality

• ORIF - Poor mechanical construct
• Leads to significant shortening and collapse
• Shortened leg
• Shortened abductor moment arm
• Limp

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Poor Bone Quality

• Collapse
• Prominent screws
• Poor gait

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Femoral Neck FracturesThe Key Factors

• Not under your control
• Bone quality
• Degree of posterior comminution
• Under surgeons control
• Accuracy of reduction
• Screw position relative to the femoral neck

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Key 1
Accuracy of Reduction
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Acceptable Reduction

• AP view
• Anatomic or slight valgus
• Cant accept varus

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Reduction Problems
Too much focus on AP view
Dont Forget the Lateral View
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Acceptable Reduction

• Lateral
• Mild or no angulation
• No anterior translation

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Femoral Neck FracturesAcceptable Reduction

• Lateral
• If shaft anteriorly translated fracture will
  collapse posteriorly
• Press femoral shaft posteriorly to reduce fracture

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Rotational Malalignment

• May be determined based on alignment of principle
  compressive trabeculae

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Closed ReductionOperative Technique

• Fracture table
• Reduction
• Confirm reduction with C-arm prior to prep

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Femoral Neck FracturesClosed Reduction

• Begin with hip extended, slightly abducted,
  externally rotated
• Apply traction
• Internally rotate to lock fracture

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Femoral Neck FracturesClosed Reduction

• If off in lateral plane
• Externally rotate to unlock fracture
• Direct force on thigh to correct displacement
• Internally rotate to lock in

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Open Reduction

• Allows visualization of fracture reduction
• Permits perfect anatomic reduction
• Permits evacuation of capsular hematoma

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Open Reduction

• Lateral skin incision
• Curve anteriorly at iliac crest to allow
  disection between tensor fascia lata and gluteus
  medius

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Open Reduction

• Incise tensor fascia lata

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Open Reduction

• Develop interval between tensor fascia lata and
  gluteus medius (Watson-Jones approach)

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Open Reduction

• Sweep fat off anterior hip capsule
• Hohmann retractor placed along anterior
  acetabular rim

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Open Reduction

• Open hip capsule
• Dissect capsule off inter-trochanteric line and
  tag with suture

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Open Reduction

• A schantz pin placed in the proximal femur can
  aid fracture reduction
• Common reduction maneuver
• Traction
• Internal rotation of shaft

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Smith-Peterson Anterior Approach

• Direct view of fracture
• Separate incisions
• Less soft tissue

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Anterior Approach
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Anterior Approach
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Key 2
Screw position relative to the femoral neck
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Femoral Neck FracturesCancellous Screw Fixation

• 3 parallel screws
• No advantage of gt 3 screws

Swiontkowski MF et al. J Orthop Res. 5 433,
1987.
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3-Point Cortical Support
61 y/o healthy woman with a valgus impacted
femoral neck fracture
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In OR
10 dayspost-op
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10 days post-op
In OR
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Two Point Fixation

• Screws passing through the osteoporotic femoral
  neck have only two points of fixation
• Lateral cortex
• Femoral head subchondral bone
• No resistance to shear forces along the plane of
  the fracture

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Two Point FixationLoss of Reduction
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Femoral Neck Cortical Support

• Evaluated screw position with respect to cortex
  of the femoral neck

Lindequist Tornkvist. J Orthop Trauma. 9
215, 1995.
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Femoral Neck Cortical Support
Number of screws with cortical support

• Union rate

• Both

16/18 (89 )
Lindequist Tornkvist. J Orthop Trauma. 9
215, 1995.
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Femoral Neck Cortical Support
Number of screws with cortical support

• Union rate

• Both
• One

16/18 (89 ) 13/22 (59 )
significantly worse, plt0.05
Lindequist Tornkvist. J Orthop Trauma. 9
215, 1995.
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Femoral Neck Cortical Support
Number of screws with cortical support

• Union rate

• Both
• One
• None

16/18 (89 ) 13/22 (59 ) 0
significantly worse, plt0.05
Lindequist Tornkvist. J Orthop Trauma. 9
215, 1995.
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Good 3-Point Cortical Support
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Femoral Neck FracturesCancellous Screw Fixation

• Avoid starting screws below level of the lesser
  trochanter
• 20 risk of subtrochanteric fracture

• Karr RK and Schwab JP.
• Clin Orthop. 194 214, 1985.

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Femoral Neck FracturesCancellous Screw Fixation

• At end of case must confirm that screws have not
  penetrated joint
• Need more than just AP and lateral image
• Live fluoroscopy
• Rotate leg or C-arm
• See end of screw approach, then withdraw from the
  articular surface

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ORIF Outcome

• Collapse during healing is common
• Altered hip mechanics
• Prominent painful screws

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ORIF Future

• Injection of resorbable cement-like material with
  growth factors
• No loss of reduction
• Improved healing

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Femoral Neck FracturesKeys to Successful ORIF

• Assess bone quality
• If OK ? ORIF
• Anatomic reduction
• Good screw position relative to the femoral neck
  (3-point cortical support)

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Thank You

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Posterior Neck Comminution

• Hip externally rotates during a fall
• Femoral neck hits against posterior acetabular
  wall
• May explain comminution often seen in posterior
  neck region