Data Collection
Information on patient demographic including age, gender, body mass index (BMI), and whether unilateral or bilateral TKA was performed was recorded based on patient perioperative medication treatment group and used to assess possible discrepancy between groups (Table 1 & 2). Data was then collected for each treatment group evaluating pre- and post-operative metrics of joint function, surgical parameters, and bloodwork.
Preoperative
Preoperative knee status was determined using Hospital of Special Surgery (HSS) total knee score, a standardized 100-point approach to TKA assessment that includes joint range of motion (ROM), joint function, and pain. Pain was further assessed using a Visual Analog Scale (VAS). Baseline blood work was recorded measuring white blood cells (WBC), hemoglobin (HGB), C reaction protein (CRP), erythrocyte sedimentation rate (ESR), and rheumatoid factor (RF). Additionally, choice of anesthesia was also recorded for each surgery.
Postoperative
HSS score, joint function, pain and VAS score were all assessed at time of latest follow-up. While ROM was measured twice, shortly postoperative prior to patient discharge and again during follow-up. Evaluation of postoperative management also included volume of wound drainage, postoperative temperature at days one and three (T pod 1 and 3), need for postoperative blood transfusion, volume of blood transfusion, and bloodwork measuring WBC, HGB and HGB drop during surgery (calculated by subtracting postoperative HGB from preoperative HGB). Patients were monitored for 3 months postoperatively for incidence of deep vein thrombosis (DVT) and short-term complications such as acute infection, delayed wound healing, need for blood transfusion, RA flare, etc., which were categorized into: systematic, wound, and surgical issues. Long term follow-up was performed approximately 10 years after TKA to document all complications that may have resulted from the operation, including periprosthetic joint infection (PJI), fracture, prosthesis loosening and need for surgical revision.
Of note, HSS score and ROM were evaluated separately for each knee in patients undergoing bilateral TKA, while other parameters such as pain were assessed jointly to better reflect overall patient disease status.