Transcript Femoral Neck Fractures - Dr. Ahmad Abanamy Hospital

Femoral Neck Fractures
Steven A. Olson, MD
Original Author: Brian Boyer, MD; March 2004;
New Author: Steven A. Olson, MD; Revised March 2006
Anatomy
• Physeal closure age 16
• Neck-shaft angle
130° ± 7°
• Anteversion
10° ± 7°
• Calcar Femorale
Posteromedial
dense plate of bone
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
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
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 & ETOH
– Young: high energy trauma
Classification
• Pauwels [1935]
– Angle describes vertical shear vector
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
Classification
• Functional Classification
– Stable
• Impacted
• Non-displaced
(Garden I)
(Garden II)
– Unstable
• Displaced
(Garden III and IV)
Treatment
• Goals
–
–
–
–
Improve outcome over natural history
Minimize risks and avoid complications
Return to pre-injury level of function
Provide cost-effective treatment
Treatment
• Options
– Non-operative
• very limited role
• Activity modification
• Skeletal traction
– Operative
• ORIF
• Hemiarthroplasty
• Total Hip Replacement
Treatment
Decision Making Variables
• Patient Characteristics
– Young (arbitrary physiologic age < 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
Treatment
Young Patients
(Arbitrary physiologic age < 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
Treatment
Elderly 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]
Treatment
Pre-operative Considerations
• Skin Traction not beneficial
–
–
–
–
–
No effect on fracture reduction
No difference in analgesic use
Pressure sore/ skin problems
Increased cost
Traction position decreases capsular volume
• Potential detrimental effect on blood flow
Treatment
Pre-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
Treatment
Pre-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
Hemi
ORIF
THR
Non-displaced Fractures
• ORIF standard of care
• Predictable healing
– Nonunion < 5%
• Minimal complications
– AVN < 8%
– Infection < 5%
• Relatively quick procedure
– Minimal blood loss
• Early mobilization
– Unrestricted weight bearing with assistive device PRN
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
Approach For Open Reduction
Smith-Peterson
• Anterior approach
• Best for transcervical
and subcapitol fractures
• Fixation is performed
through a second
approach
Approach For Open Reduction
Watson-Jones
• Anteriolateral exposure
• Best for basalar neck and
IT patterns
• Allows placement of
sliding hip screw through
same incision
What Reduction Is Acceptable?
• Ideal reduction is Anatomic
– Acceptable: < 15º valgus < 10º AP angulation
• Any varus is unacceptable
• Fixation: Multiple screws in parallel
– No advantage to > 3 screws
– Uniform compression across fracture
– In-situ pin impacted fractures
* ↑ AVN with disimpaction [Crawford 1960]
– Fixation most dependent on bone density
Screw Fixation
• Screw location
– Avoid posterior/ superior quadrant
» Blood supply
» Cut-out
– Biomechanical advantage to inferior/ calcar screw
[Booth 1998]
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
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 doesn’t hurt
Case Example 42 yo male, MVC
Open reduction via Smith-Pete approach, screw
fixation placed through separate incision
Displaced Fractures
Hemiarthroplasty 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%
Displaced Fractures
Hemiarthroplasty 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]
Hemiarthroplasty
Unipolar vs. Bipolar
• Bipolar theoretical advantages
• Lower dislocation rate
• Less acetabular wear/ protrusio
• Less Pain
• More motion
Hemiarthroplasty
Unipolar vs. Bipolar
• Bipolar
– Disadvantages
• Cost
• Dislocation often requires open
reduction
• Loss of motion interface
(effectively unipolar)
• Polyethylene wear/ osteolysis
not yet studied for Bipolars
Hemiarthroplasty
Unipolar 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
Hemiarthroplasty
Cemented 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)
Hemiarthroplasty
Cemented 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
Treatment
Pre-operative Considerations
• Surgical Approach
– Posterior approach to hip
• 60% higher short-term mortality vs. anterior
– Dislocation rate
• No significant difference
[Lu-Yao JBJS 1994]
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]
Keating et al OTA 2002
ORIF or Replacement?
• Prospective, randomized study ORIF vs.
cemented bipolar hemi vs. THA
• ambulatory patients > 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
Stress Fractures
• Patient population:
– Females 4–10 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
Stress Fractures
• Clinical Presentation
–
–
–
–
–
Activity / weight bearing related
Anterior groin pain
Limited ROM at extremes
± Antalgic gait
Must evaluate back, knee, contralateral hip
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
Stress Fractures
• Classification
– Compression sided
• Callus / fracture at inferior aspect femoral neck
– Tension sided
• Callus / fracture at superior aspect femoral neck
– Displaced
Stress Fractures
Treatment
• Compression sided
• Fracture line extends < 50% across neck
– “stable”
– Tx: Activity / weight bearing modification
• Fracture line extends >50% across neck
– Potentially unstable with risk for displacement
– Tx: Emergent ORIF
• Tension sided
• Unstable
– Tx: Emergent ORIF
• Displaced
– Tx: Emergent ORIF
Stress Fractures
Complications
• Tension sided and Compression sided fx’s
(>50%) treated non-operatively
• Varus malunion
• Displacement
– 30-60% complication rate
• AVN 42%
• Delayed union 9%
• Nonunion 9%
Femoral Neck
Nonunion
•
•
•
•
Definition: not healed by one year
0-5% in Non-displaced fractures
9-35% in Displaced fractures
Increased incidence with
–
–
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Posterior comminution
Initial displacement
Inadequate reduction
Non-compressive fixation
Femoral Neck
Nonunion
• 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
Femoral Neck
Nonunion
• Treatment
– Elderly patients
• Arthroplasty
– Results typically not as good as primary elective
arthroplasty
• Girdlestone Resection Arthroplasty
– Limited indications
– deep infection?
Femoral Neck
Nonunion
• Young patients
(must have viable femoral head)
– Varus alignment or limb
shortened
• Valgus-producing osteotomy
– Normal alignment
• Bone graft / muscle-pedicle
graft
• Repeat ORIF
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
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
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
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 **
Femoral Neck Fractures
Complications
• Failure of Fixation
– Inadequate / unstable reduction
– Poor bone quality
– Poor choice of implant
• Treatment
– Elderly: Arthroplasty
– Young: Repeat ORIF
Valgus-producing osteotomy
Arthroplasty
Femoral Neck Fractures
Complications
• Post-traumatic arthrosis
• Joint penetration with hardware
• AVN related
• Blood Transfusions
– THR > Hemi > ORIF
– Increased rate of post-op infection
• DVT / PE
– Multiple prophylactic regimens exist
– Low dose subcutaneous heparin not effective
Femoral Neck Fractures
Complications
• One-year mortality 14-50%
• Increased risk:
–
–
–
–
–
Medical comorbidities
Surgical delay > 3 days
Institutionalized / demented patient
Arthroplasty (short term / 3 months)
Posterior approach to hip
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