The reconstruction of the distal femur using modular systems has become increasingly popular over the years, surpassing primary arthrodesis or amputation. Despite the significant advantages of using megaprostheses, complications are not uncommon. Although the Limb Preservation System™ (LPS™, DePuy Synthes; Warsaw, USA) is one of the most widely used megaprostheses in the French market, there is currently no national evaluation of this system, and only two studies have been conducted worldwide.

The aim of our study is to present the mid-term survival rates of the LPS™ implant in order to answer three main questions:

1. What are the overall outcomes of the LPS™ system in distal femur replacement?
2. What factors are associated with a reduced survival rate of the implant?
3. What is the cumulative risk of complications according to Henderson's classification?

The secondary objective is to analyze the occurrence of specific failures, providing insights for potential improvements in the design and use of the LPS™ implant.

Inclusion Criteria:

- Patients who underwent distal femoral reconstruction using the LPS system.

Exclusion Criteria:

• Lost to follow-up before 3 months.
• Associated tibial reconstruction using the LPS system.
• Total femoral reconstruction using the LPS system.

The institutional databases of university hospitals belonging to the HugOrtho network (Hôpitaux Universitaires du Grand Ouest) will be examined to identify patients who will have undergone reconstruction using the Limb Preservation System™ (LPS™, DePuy Synthes; Warsaw, USA) for segmental resection of the distal femur, regardless of the indication.

All collected data that underlie results in a publication

Data will be available beginning three years and ending fifteen years following the final study report completion

Data access requests will be reviewed by the internal committee of Brest UH. Requestors will be required to sign and complete a data access agreement