Background: The purpose of this study was to review internal fixation of humerus fractures using a large national database and assess the incidence of implant removal procedures based on patient characteristics.
Methods: The 2007 Nationwide Inpatient Sample was used to identify two different sets of patients: (1) all patients who received an open internal fixation procedure for a fracture of the upper end, shaft, or lower end of the humerus; and (2) all patients with a removal of implanted devices from the humerus. Patient variables included age, gender, race/ethnicity, median household income, patient geographic region, metropolitan location, and primary expected payor. The differences of characteristics between both groups were determined using χ, Fisher's exact, or unpaired t tests.
Results: Open reduction with internal fixation was reported in 7,391 patients. Hardware removals were reported in 751 patients who were determined to have an associated diagnosed complication. From these numbers, the "failure" removal rate as a percentage of the total number of procedures for the year was 10.2%. Nonunion (17.5%) and Mechanical Complication of the Implant (16.2%) were the most common complications. Both payor (p=0.0023) and age (p<0.0001) were found to have significantly different distributions among the open reduction with internal fixation and removal groups.
Conclusion: These results suggest that the age of the patient and the patient's ability to pay may influence the likelihood of an implant removal procedure. The results will help identify patients who are at high risk for revision and who may benefit from preventative care.