1. Volume 4, Issue 2, Pages 153-157 (June 2018)
Two pegs are better than one: rare mode of femoral component failure in unicompartmental arthroplasty requiring revision to total knee arthroplasty 
Ryan Stancil, MD, Nathan Summers, PA-C, Douglas Van Citters, PhD, MS, Adam Sassoon, MD, MS 
Arthroplasty Today 
Volume 4, Issue 2, Pages (June 2018)
DOI: /j.artd
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2. Figure 1
Anteroposterior radiograph of right knee with no evidence of UKA failure.
Arthroplasty Today 2018 4, DOI: ( /j.artd )
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3. Figure 2
Lateral radiograph of a right knee with a medial UKA. Note the lucency posterior to the single femoral peg.
Arthroplasty Today 2018 4, DOI: ( /j.artd )
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4. Figure 3
Intraoperative photograph showing the clearly fractured and grossly loose femoral UKA component.
Arthroplasty Today 2018 4, DOI: ( /j.artd )
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5. Figure 4
(a) Anteroposterior and (b) lateral radiographs of final TKA components at 1 year postoperatively.
Arthroplasty Today 2018 4, DOI: ( /j.artd )
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6. Figure 5 Explanted Vanguard femoral UKA component.
Arthroplasty Today 2018 4, DOI: ( /j.artd )
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7. Figure 6
Close-up of fracture through femoral UKA component with evidence of fatigue striations.
Arthroplasty Today 2018 4, DOI: ( /j.artd )
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8. Figure 7
Close-up of the articular surface of the explanted femoral component with signs of scratching and burnishing.
Arthroplasty Today 2018 4, DOI: ( /j.artd )
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9. Figure 8
Electron microscopy revealing crack initiation and propagation sites.
Arthroplasty Today 2018 4, DOI: ( /j.artd )
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10. Figure 9 Electron microscopy showing crack around grain boundaries.
Arthroplasty Today 2018 4, DOI: ( /j.artd )
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11. Figure 10
Microstructure overview showing the presence of carbide precipitates within the grains as well as intermetallic phases along the grain boundaries.
Arthroplasty Today 2018 4, DOI: ( /j.artd )
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