Does well‐controlled overt hypothyroidism increase the risk of total knee arthroplasty?

Abstract

Background: Overt hypothyroidism is widely accepted as a risk factor for adverse events following total knee arthroplasty (TKA). However, no prior study has preoperatively reversed hypothyroidism and reevaluated its risk. This retrospective study aimed at investigating whether well-controlled overt hypothyroidism would still increase the risk of TKA. Methods: Between November 2009 and November 2016, patients diagnosed with overt hypothyroidism but well controlled and underwent TKA were compared with euthyroid TKA patients. Data were extracted from our departmental database. Chi-squared test and ttests were used for comparisons. Results: Hypothyroid patients had more blood loss and lower postoperative haemoglobin (Hb) and haematocrit level than the control group (all P < 0.05). Although the postoperative anaemia rate was lower in the control group (P = 0.01), there was no significant difference in the transfusion rate between the two groups (2.99% versus 7.46%, P = 0.10) or in the rates of other complications (P > 0.05). Interestingly, intramuscular venous thrombosis rate in hypothyroid patients was significantly lower than that in the control group (1.49% versus 9.70%, P = 0.00). Clinical outcome scores were comparable between the two groups throughout the course. And only one case of infection occurred in the hypothyroid patients. Conclusion: Well-controlled overt hypothyroidism did not increase the risk of TKA, except for perioperative blood loss. Surgeons should be aware that even if hypothyroidism is reversed, the risk of more perioperative blood loss still exists and that, consequently, perioperative blood management is still essential in this population.

Is thyroid disease associated with post-operative complications after total joint arthroplasty? A systematic review of the literature

“…All studies reporting perioperative blood loss-related complications demonstrated a significantly higher rate of postoperative anemia in hypothyroid than euthyroid patients undergoing TJA ( 7 , 14 , 16 , 17 ). These studies also showed a significant increase in transfusion rates in patients with hypothyroidism, except for the study by Yuan et al .…”

“…They mainly were retrospective and prospective observational and cohort studies. One study presented data on total ankle arthroplasty ( 13 ); four studies presented data on TKA ( 7 , 14 , 15 , 16 ); one study included data on THA ( 17 ); and one for total elbow arthroplasty ( 18 ). Two studies demonstrated data on both TKA and THA operations ( 19 , 20 ).…”

“…( 18 ) 2019 RC Elbow 1452 1132 106 PJI: 62 60 3 Yuan et al . ( 16 ) 2020 RC Knee 134 134 232 36 TD: 67.29 65.96 69.6 Yuan et al . ( 17 ) 2020 RC Hip 63 63 68 58 TD 53.4 56.1 78 Jing et al ( 14 ) 2021 CS Knee 398 398 700 96 TD: 64.8 65.1 25.4 Yang.…”

“…Three cohort studies ( 7 , 14 , 16 ) were measured to be of high methodological quality and one ( 17 ) of moderate quality. A cross-sectional study was of high ( 20 ), three of moderate ( 15 , 19 , 21 ), and one of low methodological quality ( 18 ).…”

“…Five of the included studies reported postoperative medical complications ( 7 , 14 , 16 , 17 , 19 ). In two studies, the rate of deep venous thrombosis, pneumonia, and non-specified cardiac complications was significantly increased among hypothyroid patients.…”