*4.1.1 Femur*

There were several classification systems described for supracondylar periprosthetic fracture of femur. Rorabeck et al. developed a classification that described fracture configuration and integrity of prosthesis to guide appropriate management of each fracture pattern. The key factors considered in the classification were the fracture displacement and the prosthesis stability [43, 44]. This classification later was widely known as "Lewis and Rorabeck classification" (**Table 6**).

The Lewis and Rorabeck classification recommended nonoperative treatment for type I classification [44]. However, Su et al. suggested surgical management in any type of fracture because of the high complication rate and further displacement in case of conservative treatment. An alternative classification was developed and proposed to characterize the fracture line in relation to the component for help in choosing among surgical options (**Figure 1**; **Table 7**) [45].

*Complications after Total Knee Arthroplasty: Stiffness, Periprosthetic Joint Infection… DOI: http://dx.doi.org/10.5772/intechopen.105745*


#### **Table 6.**

*Lewis and Rorabeck classification.*


#### **Table 7.** *Su classification.*

#### **Figure 1.**

*Anteroposterior and lateral radiographs showing periprosthetic fracture of TKA (A) Su classification type I; Lewis and Rorabeck classification type II (B) Su classification type II; Lewis and Rorabeck classification type II (C) Su classification type III; Lewis and Rorabeck classification type III.*
