Frequency and Complications of Major Orthopedic Procedures in Medicare Beneficiaries

Background: \- Orthopedic procedures are common in the United States. These include joint replacement and spine surgeries. Researchers want to study data about these procedures over time. They want to see if treatment has gotten better. They also want to find ways to change the care that people get before and after they have these procedures. These changes may lower the risk of problems people can have during and after treatment. They may also improve people s results. Objectives: \- To study a series of questions about surgery, medicine, treatments, and outcomes for orthopedic procedures. Eligibility: \- Data from the U.S. Centers for Medicare and Medicaid Services from 1999 to 2015. Design: * Researchers will look at data for people ages 20-100. * No new participants will be used in this study. * The study will last 6 years....

* Subjects will be either Medicare or Medicaid beneficiaries with available claims from 1999 to 2015. For projects requiring detailed medication information, inclusion will be limited to those with Part D claims from 2006 to 2015. Eligibility for each project will be based on claims for the appropriate disease (e.g. RA) or procedure (e.g. hip arthroplasty). Medicare beneficiaries will be excluded (or censored) if they do not have both Part A and Part B coverage, or enrolled in Medicare Advantage plans (Part C), as detailed claims for these beneficiaries are not available. We will also exclude dual-eligible (Medicare and Medicaid recipients) as these subjects have distinct clinical conditions (e.g. blindness) that distinguishes them from most Medicare beneficiaries. There will be no exclusions based on gender, race, ethnicity, or cognitive impairment.