The gold standard after shoulder resection for tumors is reconstruction by reverse prosthesis and allograft. This is an intervention also performed for more frequent etiologies (revisions of prosthesis, non cancerous humeral bone loss ...).

The results in these etiologies are good, and do not find any particular mechanical complications (including no osteolysis of the graft). In the case of reconstruction for cancer, the numbers of patients are lower (rare pathologies) and some studies on small numbers found osteolysis of the allograft. The aim of this study is to analyze the presence or not osteolysis in these patients, and to quantify it precisely by scanner measurement (no data yet in the literature).

quantify bone stock of the allograft by scanner measurement in post operative and in 6 month to 1 years after surgery.

This is a retrospective study, and the scanner was performed routinely every 3 to 6 month, during 2 years, for oncological follow up.

Inclusion Criteria:

• tumors of proximal humerus
• Malawer type I resection
• primary reconstruction by allograft prosthetic composite

Exclusion Criteria:

• resection and reconstruction by prosthesis alone
• resection and reconstruction by prosthesis and cement sleeve reconstruction
• resection and reconstruction by hemiarthroplasty
• revision protheses.

All patients treated for tumors of proximal humerus, who underwent a Malawer type I resection of this tumors