Table 1.

A2CPS eligibility criteria.

	Inclusion criteria	Exclusion criteria
A2CPS Common Criteria	1. Provision of signed and dated informed consent form 2. Stated willingness to comply with all study procedures and availability for the duration of the study 3. Age 18–85 years	1. Patients unable to provide informed consent or unable to read/speak English or Spanish 2. Patients with known contra-indications to magnetic resonance imaging (MRI)
Knee Arthroplasty Cohort	1. Individuals diagnosed with knee osteoarthritis scheduled to undergo a single primary partial or total knee replacement; conversion of a partial to total knee replacement for mechanical failure (aseptic loosening, implant fracture, instability), wear-related complications (osteolysis, synovitis) or component malposition; or a revision of a knee replacement for mechanical failure (aseptic loosening, implant fracture, instability), wear-related complications (osteolysis, synovitis) or component malposition. All surgical approaches including robotic-controlled and muscle-sparing techniques will be included for the study.	1. Patients undergoing unilateral primary partial or total knee replacement for an inflammatory arthritic condition such as rheumatoid arthritis or osteonecrosis 2. Patients undergoing revision surgery with an infectious diagnosis involving the joint to be replaced (as this will be a 2-stage procedure) 3. Patients undergoing bilateral knee replacements, planned staged bilateral knee replacements within 3 months of each other, or are within 3 months of a prior contralateral knee replacement
Thoracic Surgery Cohort	1. Individuals who are scheduled for surgery using a thoracic approach (including thoracotomy, VATS, and robotic surgery) at any of the participating hospitals	1. Patients who have undergone prior thoracic surgery within 3 months 2. Patients undergoing a bilateral thoracic procedure 3. Patients undergoing another planned major surgery in the 6-month follow-up period