Reverse Total Shoulder Arthroplasty in an Adult With Achondroplasia

Background: Achondroplasia can result in many skeletal manifestations, and degenerative osteoarthritis can develop in patients with achondroplasia. Morphologic changes to both the humerus and glenoid—short humeri with patulous metaphyses and a medialized glenoid—can cause challenges that must be overcome to achieve a successful surgical result in a patient with shoulder dysfunction. Because patients with achondroplasia have near-normal life expectancies, the operative shoulder must be functional as well as quite durable in the long term. In an achondroplastic dwarf with shoulder osteoarthritis and rotator cuff insufficiency, achieving functionality and durability requires the use of a reverse total shoulder arthroplasty (TSA). This procedure has its own set of issues, namely, baseplate fixation and correction of glenoid medialization, if present. Case Report: We present the case of an adult with achondroplastic dwarfism with shoulder osteoarthritis and rotator cuff insufficiency and report the 2-year clinical results for this patient after reverse TSA. Conclusion: Reverse TSA is a viable treatment option for adult achondroplastic patients with shoulder dysfunction. Careful preoperative planning is required to ensure a good clinical result in patients with potentially dysplastic anatomy.