The purpose of this study is to more fully understand the reason(s) that joint replacement implants fail and to better identify diagnosis and outcome methods both pre-operatively and post-operatively with revision surgery. Analysis of joint replacement failure will include a through analysis of laboratory, radiographic, implant, surgical and demographic data.

To examine all clinical data in patients with failed total hip and total knee replacements including patient demographics (age, sex, comorbidities, etc.), patient clinical data (history and physical exam and lab findings) and including implant specifications and radiographic findings (for implant type, implant size, implant bearing surface type, position, stability, etc.).

Inclusion Criteria:

• ≥18 years of age
• failed hip or knee replacement
• willing to sign informed consent

Exclusion Criteria:

• none

Patients ≥18 years of age, that present with a failed joint replacement.