The purpose of this study is to follow the patient's short term and long term clinical outcome after undergoing joint replacement surgery.

This is a registry database. Consented subjects will have their medical data collected via a patient questionnaire in either paper or web based application form. Data will be collected prospectively and retrospectively and will be entered into the database generated by Memorial Bone and Joint Research Foundation. Collection of data will start during the initial clinic visit as part of standard of care. Subjects will be asked to fill out a 4-page "pre-operative hip questionnaire" or "pre-operative knee questionnaire", which includes questions for self-assessment from the Hip Disability and Osteoarthritis Outcome Score (HOOS), Knee disability and Osteoarthritis Outcome Score (KOOS), EQ-5D and University of California, Los Angeles Activity (UCLA) questionnaires. Demographic, intra-operative and additional data will also be collected to correctly identify the subject's specific disease process and treatment plan. Subjects will be asked to fill out a post-operative hip and knee questionnaire that is similar to the pre-operative questionnaire to evaluate the improvement in their clinical outcomes. The subjects will be requested to complete the post-operative questionnaires at 6 months and annually thereafter.

Inclusion Criteria:

• Inclusion criteria will be limited to subjects who have consented to undergo elective total joint replacement, hip resurfacing and partial knee surgery, arthroscopy and Femoro-actabular impingement (FAI) release performed by the PI.
• All patients of legal adult age will be eligible for the study. All patients will have an equal chance to participate in the study regardless of race or gender. Patients will be enrolled in the order as they are diagnosed by the PI.

Exclusion Criteria:

• Exclusion criteria will be limited to morbid obesity, active infection, heart failure, lung failure, severe bleeding abnormalities, subject with known metal allergy, subject who cannot legally decide for themselves.

Hip and knee replacement patients treated by the principal investigator.