Combinatorics

Cage

Avascular necrosis

Population

Mathematics

Orthopedic surgery

Surgery

Fixation (population genetics)

Humerus

Arthroplasty

Femoral head

Proximal humerus

Medicine

Intramedullary rod

Environmental health

JBJS Case Connector

Case: The expandable intramedullary cage (Conventus Orthopaedics) may treat 3- and 4-part proximal humerus fractures. Cage removal for symptomatic avascular necrosis with humeral head collapse requiring conversion to arthroplasty can be challenging because the cage's collapsing mechanism becomes inoperable after fracture consolidation. We present cage explantation followed by reverse total shoulder prosthesis placement in a 54-year-old man who underwent plate/cage fixation for a 3-part proximal humerus fracture 10 months earlier. Conclusion: The proximal humeral cage can be extracted safely while preserving adequate bone stock for subsequent arthroplasty. Additional time and exposure are necessary compared with removing a locking plate alone.

Intramedullary Cage Removal for a Consolidated Proximal Humerus Fracture