Fracture of the Tibial Baseplate 16 Years after Miller-Galante II Total Knee Arthroplasty

Figure 6

(a) Gross observation of the retrieved broken tibial baseplate reveals that the fracture line extended in a coronal direction from the medial corner to the posterior cruciate ligament (PCL) recess. (b) Gross observation of the undersurface of the tibial baseplate shows uneven bone attachment surrounding the medial fracture line but even bone attachment at the posterolateral portion. (c) Surface of the break is complex rather than with regular fracture waves. A focal stair-step pattern can be observed grossly at the medial corner of the PCL recess (arrow), indicating a fatigue fracture. Scanning electron micrography shows fatigue striations (circle). (d) Retrieved polyethylene insert has severely worn medial sites that correspond to the posteromedial breakage area of the tibial baseplate. Polyethylene insert is also severely worn at the posterolateral area. (e) Retrieved portion of the fractured screw.

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