1.
The effect of post-operative limb positioning on blood loss and early outcomes after primary total knee arthroplasty: a randomized controlled trial
Wu Y, Zeng Y, Li C, Zhong J, Hu Q, Pei F, Shen B
International Orthopaedics. 2018
Abstract
INTRODUCTION The purpose of this study was to investigate the benefits of three different post-operative limb positions in primary total knee arthroplasty (TKA). METHODS The trial was a single-surgeon, randomized, controlled trial, and 135 patients following primary TKA were randomized into three groups: group A (45 patients who were treated with the hip fixed at 50 degrees and knee flexed at 90 degrees for 6 hours post-operatively), group B (45 patients who were treated with the hip elevated at 30 degrees and knee flexed at 45 degrees for 6 hours post-operatively), and group C (45 patients in whom the affected knee was fully extended after surgery). Tranexamic acid was used in all patients. RESULTS The total blood loss and hidden blood loss in group A (921 +/- 209 mL, 597 +/- 213 mL) were significantly less than in groups B (1125 +/- 222 mL, 784 +/- 229 mL) and C (1326 +/- 291 mL, 915 +/- 301 mL) and less in group B compared with group C. The drain volume in groups A (158 +/- 35 mL) and B (174 +/- 45 mL) was significantly lower than in group C (249 +/- 31 mL). The maximum haemoglobin drop in group A (3.1 +/- 0.5 g/dL) was statistically significantly less than in groups B (3.6 +/- 0.7 g/dL) and C (4.3 +/- 0.4 g/dL). The range of motion (ROM) in groups A (102 +/- 3 degrees , 105 +/- 2 degrees ) and B (100 +/- 3 degrees , 104 +/- 2 degrees ) was significantly better than in group C (98 +/- 3 degrees , 102 +/- 2 degrees ) at the time of discharge and one month after surgery; it was also significantly less for group A (104.9 +/- 2.1%, 108.0 +/- 2.4%) compared with groups B (106.7 +/- 3.1%, 108.3 +/- 2.7%) and C (108.4 +/- 3.2%, 110.6 +/- 3.0%) with post-operative knee swelling. No differences in transfusion requirements and complications were observed among the three groups. CONCLUSIONS The affected knee flexion position was superior to the use of a fully extended position for blood management, but it only contributed to better early functional recovery up to three months post-operatively in TKA. In addition, by fixing the affected knee at a high flexion position of 90 degrees , patients could achieve less blood loss, lower knee swelling, and better early results for ROM and patient satisfaction than the other two groups.
2.
Effect of different postoperative limb positions on blood loss and range of motion in total knee arthroplasty: An updated meta-analysis of randomized controlled trials
Wu Y, Yang T, Zeng Y, Si H, Li C, Shen B
International Journal of Surgery (London, England). 2016;37:15-23
Abstract
BACKGROUND Postoperative limb positioning has been reported to be an efficient and simple way to reduce blood loss and improve range of motion following total knee arthroplasty (TKA). This meta-analysis was designed to compare the effectiveness of two different limb positions in primary TKA. MATERIALS AND METHODS A meta-analysis of the PubMed, CENTRAL, Web of Science, EMBASE and Google Search Engine electronic databases was performed. In this meta-analysis, two postoperative limb positions were considered: mild-flexion (flexion less than 60 degrees ) and high-flexion (flexion at 60 degrees or more). The subgroups were analysed using RevMan 5.3. RESULTS Nine RCTs were included with a total sample size of 913 patients. The mild- and high-flexion positions significantly reduced postoperative total blood loss (P = 0.04 and P = 0.01; respectively). Subgroup analysis indicated that knee flexion significantly reduced hidden blood loss when the knee was fixed in mild-flexion (P = 0.0004) and significantly reduced transfusion requirements (P = 0.03) and improved range of motion (ROM) (P < 0.00001) when the knee was fixed in high-flexion. However, the rates of wound-related infection, deep venous thrombosis (DVT) and pulmonary embolism (PE) did not significantly differ between the two flexion groups. CONCLUSION This meta-analysis suggests that mild- and high-flexion positions have similar efficacy in reducing total blood loss. In addition, subgroup analysis indicates that the mild-flexion position is superior in decreasing hidden blood loss compared with high-flexion; the high-flexion position is superior to mild-flexion in reducing transfusion requirements and improving postoperative ROM. Thus, the use of the high-flexion position is a viable option to reduce blood loss in patients following primary TKA without increasing the risk of wound-related infection, DVT or PE.