A systematic review of endoprosthetic replacement versus cement spacer in reconstruction of proximal humerus following proximal humerus metastasis

Background
The choice between cement spacer and endprosthesis in the treatment of metastatic lesions to the proximal humerus is increasingly controversial. However, it may be easier to categorize the patients, and their socioeconomic and perioperative parameters into two groups.
Aim
This work aims to review the available literature on the topic of endoprosthetic replacement versus cement spacer in the reconstruction of the proximal humerus following metastatic lesions to the proximal humerus regarding the surgical technique, its indications, its advantages, and limitations.
Patients and methods
We followed the preferred reporting items for systematic review and Meta-analysis (PRISMA) statement guidelines during this systematic review and performed all steps according to the Cochrane Handbook of Systematic Reviews of Intervention.
Results
Four studies were included in this systematic review, and a total of 100 patients were included (22 of which had cement spacer and 78 had endprosthesis). Several parameters were compared in the reviewed studies including the MSTS score of the patients; the primary tumor; postoperative complications; the patients’ age; follow-up periods; and the presenting symptoms of the patients.
Conclusion
This systematic review suggests that the cement spacer technique is not inferior to endoprosthetic replacement of the proximal humerus in cases of metastases. Therefore, we suggest that determining whether to use an end prosthesis or a cement spacer depends on categorizing the patients into two groups. Endoprosthetic replacement will be an appropriate choice for patients with preserved deltoid and axillary nerve function following resection, solitary and nonaggressive metastatic lesion, and long-life expectancy with minimal co-morbidities. We believe that cement spacer is a more appropriate choice in patients with nonfunctioning deltoid or axillary nerve following resection; multiple and aggressive metastatic lesions; short life expectancy with many co-morbidities, and poor socioeconomic status.