Total hip and knee replacement surgery results in changes in leukocyte and endothelial markers

Abstract

Background: It is estimated that over 8 million people in the United Kingdom suffer from osteoarthritis. These patients may require orthopaedic surgical intervention to help alleviate their clinical condition. Investigations presented here was to test the hypothesis that total hip replacement (THR) and total knee replacement (TKR) orthopaedic surgery result in changes to leukocyte and endothelial markers thus increasing inflammatory reactions postoperatively.

Methods: During this 'pilot study', ten test subjects were all scheduled for THR or TKR elective surgery due to osteoarthritis. Leukocyte concentrations were measured using an automated full blood count analyser. Leukocyte CD11b (Mac-1) and CD62L cell surface expression, intracellular production of H(2)O(2 )and elastase were measured as markers of leukocyte function. Von Willebrand factor (vWF) and soluble intercellular adhesion molecule-1 (sICAM-1) were measured as markers of endothelial activation.

Results: The results obtained during this study demonstrate that THR and TKR orthopaedic surgery result in similar changes of leukocyte and endothelial markers, suggestive of increased inflammatory reactions postoperatively. Specifically, THR and TKR surgery resulted in a leukocytosis, this being demonstrated by an increase in the total leukocyte concentration following surgery. Evidence of leukocyte activation was demonstrated by a decrease in CD62L expression and an increase in CD11b expression by neutrophils and monocytes respectively. An increase in the intracellular H(2)O(2 )production by neutrophils and monocytes and in the leukocyte elastase concentrations was also evident of leukocyte activation following orthopaedic surgery. With respect to endothelial activation, increases in vWF and sICAM-1 concentrations were demonstrated following surgery.

Conclusion: In general it appeared that most of the leukocyte and endothelial markers measured during these studies peaked between days 1-3 postoperatively. It is proposed that by allowing orthopaedic surgeons access to alternative laboratory markers such as CD11b, H(2)O(2 )and elastase, CD62L, vWF and sICAM-1, an accurate assessment of the extent of inflammation due to surgery per se could be made. Ultimately, the leukocyte and endothelial markers assessed during this investigation may have a role in monitoring potential infectious complications that can occur during the postoperative period.

Figure 1

Effect of THR and TKR surgery on total leukocyte concentration. The points represent mean ± SD. p = <0.05 for THR and TKR, as determined by ANOVA and the Friedman tests respectively. p = 0.05 baseline vs day 1 postoperative THR, as determined by pairwise comparison testing; p = <0.05 baseline vs 5 minutes reperfusion, day 1 and day 3 postoperative TKR, as determined by the Wilcoxon test. (*, p < 0.05 compared to baseline).

Figure 2

Effect of THR and TKR surgery on CD62L cell surface expression of neutrophils (A) and monocytes (B). A, the points represent mean ± SD. p = <0.001 for neutrophils following THR and TKR surgery, as determined by ANOVA and the Friedman tests respectively. Baseline vs day 3 postoperative following THR p = 0.017, as determined by pairwise comparisons. p = <0.05 baseline vs 5 and 15 minutes reperfusion, day 1 and day 3 postoperatively following TKR (Wilcoxon test). (* = p < 0.05 compared to baseline). B, the points represent mean ± SD. p = >0.05 for monocytes following THR and TKR surgery.

Figure 3

Effect of THR and TKR surgery on CD11b cell surface expression of neutrophils (A) and monocytes (B). A, the points represent mean ± SD. p = <0.05 for neutrophils following THR and TKR surgery, as determined by ANOVA. Baseline vs day 3 postoperative following THR (p = 0.027, as determined by pairwise comparisons). Baseline vs 15 minutes reperfusion, following TKR (p = 0.022, as determined by pairwise comparisons). (*, p < 0.05 compared to baseline). B, the points represent mean ± SD. p = 0.004 for monocytes following TKR, as determined by ANOVA.

Figure 4

Effect of THR and TKR surgery on intracellular H₂O₂ production of neutrophils (A) and monocytes (B). A, the points represent mean ± SD. p = 0.035, as determined by ANOVA following THR surgery. B, the points represent mean ± SD. p = 0.002, as determined by ANOVA following TKR surgery. Baseline vs day 1 postoperative following TKR (p = 0.011, as determined by pairwise comparisons) (*, p < 0.05 compared to baseline).

Figure 5

Effect of THR and TKR surgery on elastase concentration. The points represent mean ± SD, p = 0.003 for TKR surgery, as determined by the Friedman test. p = <0.05 baseline vs 15 minutes reperfusion, day 1 and day 3 postoperative, as determined by the Wilcoxon test. (*, p < 0.05 compared to baseline).

Figure 6

Effect of THR and TKR surgery on vWF concentration. The points represent mean ± SD, p = <0.001 TKR surgery, as determined by ANOVA. Baseline vs day 3 postoperative for TKR surgery (p = <0.05), as determined by pairwise comparison tests. (*, p < 0.05 compared to baseline).

Figure 7

Effect of THR and TKR surgery on sICAM-1 concentration. The points represent mean ± SD, p = 0.032 for THR surgery, as determined by ANOVA.