Although it is currently known that post-operative hematoma leads to adverse outcomes following total knee arthroplasty, there is currently no literature to quantify the average size or progression of the intra-articular bleeding post operatively. It would be reasonable to assume that all patients develop a slight hematoma post operatively. The investigator aims to assess the size, and possible progression of the intra-articular hematoma following total knee arthroplasty.