Navigation makes more accurate femur resection compared to conventional total knee arthroplasty in lateral femoral bowing greater than 5º.

There are many disagreements about the merits of navigation in total knee arthroplasty (TKA). We compared and analyzed the difference in the accuracy of femoral resection according to the degree of lateral femoral bowing in 2 surgical methods (conventional and navigation-assisted TKA). A total of 238 (100 who underwent navigation TKA and 138 who underwent conventional TKA from 2016 to 2021) were included in this study. The surgeon first performed TKA as the main operator in 2016. Most of the TKAs were navigation-assisted between 2016 and 2018, and most of the TKAs were conventional between 2019 and 2021. For more accurate distal femoral cutting in patients with lateral femoral bowing, a preoperative scanogram was used to set up the insertion point of the IM rod in conventional TKA. Femoral lateral bowing was divided into 3 groups based on the angle. Group 1 was divided into groups with negative values, group 2 into mild bowing of 0° to 5°, and group 3 into groups with moderate bowing of ≥ 5°. The postoperative mechanical hip knee ankle angle and mechanical lateral distal femoral angle (mLDFA) were aimed to be 0° and 90°. The allowable ranges of these values were set as 0°â€…±â€…3° and 90°â€…±â€…3°, respectively. The distribution of outliers of the mLDFA in the 3 groups divided according to lateral femoral bowing in the navigation-assisted group was not statistically significant difference (P = .59). On the other hand, the distribution of outliers of mLDFA was statistically significant difference in the conventional method group (P = .01). The odds ratio of the outlier occurrence of mLDFA in the conventional method was 2.50, which was statistically significant (P = .03). Also, when the lateral femoral bowing value was moderate; i.e., ≥5°, the odds ratio was 4.20, which was statistically significant (P = .003). In the case of navigation-assisted TKA, the accuracy of femur resection was consistent regardless of the degree of lateral femoral bowing. However, in conventional TKA, the outlier of femur resection increased as lateral femoral bowing increased. Especially, for patients with lateral femoral bowing >5°, navigation-assisted TKA allows for more accurate femur resection compared to conventional TKA.

Effects of intraoperative or postoperative administration of intravenous iron supplements on hemoglobin recovery in patients with total knee arthroplasty: A systematic review and meta-analysis.

BACKGROUND: The objectives of the researchers are as follows: First, to investigate whether intraoperative or postoperative administration of Intravenous (IV) iron supplements in patients undergoing primary total knee arthroplasty (TKA) can contribute to the hemoglobin recovery during the postoperative period (between 4 and 8 weeks after surgery). Second, to examine whether the administration of IV iron supplements during or immediately after TKA in patients undergoing primary TKA can reduce the need for allogenic blood transfusion during hospitalization. METHODS: Articles published between January 1, 1990, and June 30, 2023 were searched in PubMed, Cochrane, and Embase. The population, intervention, comparison, and outcome of this study are as follows; Population: Patients undergoing primary total knee arthroplasty; Intervention: Administration of IV iron supplements during or immediately after surgery; Comparison: Non-administration of IV iron supplements; Outcome: Degree of hemoglobin recovery (between 4 and 8 weeks after surgery) and the need for blood transfusion during hospitalization. RESULTS: There was a statistically significant difference in the amount of change in hemoglobin between iron supplementation group and non-iron supplementation group. The effect size were -0.44 (95% confidence interval: -0.69 to -0.19, P value < .001) in all patients. This means that the amount of change in hemoglobin were significantly reduced in the iron supplementation group than in the non-iron supplementation group. There was a statistically significant difference for post-operative transfusion rate between 2 groups. The effect size were 0.28 (95% confidence interval: 0.10-0.81, P value = .02) in all patients. This means that the post-operative transfusion rate was significantly less in the iron supplementation group than in the non-iron supplementation group. CONCLUSION: The administration of IV iron supplements during or after TKA surgery increases hemoglobin recovery between 4 and 8 weeks after surgery and reduces the need for allogeneic blood transfusion during hospitalization.