The Assessment of Blood Loss During Total Knee Arthroplasty When Comparing Intravenous vs Intracapsular Administration of Tranexamic Acid.

BACKGROUND: Administration of tranexamic acid topically and intravenously has demonstrated effectiveness in decreasing blood loss and transfusion rates. METHODS: We randomized 131 patients undergoing primary total knee arthroplasty to receive either intracapsular (69) or intravenous tranexamic acid (62). Postoperative blood loss was calculated using the formula derived by Nadler et al. The number of units transfused was recorded, as well as length of hospital stay. RESULTS: We found no statistically significant difference on calculated blood loss (postoperative day [POD] 1: 624 ± 326 vs 644 ± 292; P = .71, POD 2: 806 ± 368 vs 835 ± 319; P = .64, and POD 3: 1076 ± 419 vs 978 ± 343; P = .55). There was no difference in number of blood transfusions, length of stay, or complications. CONCLUSION: Intracapsular tranexamic acid is not inferior to intravenous tranexamic acid in decreasing blood loss and blood transfusion rate in primary total knee arthroplasty.

Can a high-flexion total knee arthroplasty relieve pain and restore function without premature failure?

BACKGROUND: High-flexion TKA prostheses are designed to improve flexion and clinical outcomes. Increased knee flexion can increase implant loads and fixation stresses, creating concerns of premature failure. Whether these goals can be achieved without premature failures is unclear. QUESTIONS/PURPOSES: We assessed pain relief, knee motion, function, incidence of premature failure, and radiographic appearance in patients with a mobile-bearing high-flexion TKA and determined whether preoperative knee flexion affects postoperative knee flexion. PATIENTS AND METHODS: We prospectively followed all 142 patients implanted with 154 mobile-bearing high-flexion TKAs between 2004 and 2007. We obtained Knee Society scores (KSS) and assessed radiographs for loosening. Minimum followup was 24 months (mean, 46 months; range, 24-79 months). RESULTS: Average knee flexion improved from 123° to 129°. Patients with preoperative flexion of 100° to 120° had a greater postoperative flexion increase (mean, 13°; range, 114°-126°) than patients with preoperative flexion of greater than 120° (mean, 3.0°; range, 128°-131°). The mean KSS improved from 41 to 95 postoperatively. Patients with preoperative flexion of less than 120° had a greater improvement in KSS (62 versus 48). Posterior femoral radiolucent lines were observed in 43% without evidence of prosthetic loosening. CONCLUSIONS: Our data were similar to those reported in patients implanted with traditional and other designs of high-flexion TKA. We found no increased incidence of premature failure, although a higher than expected incidence of posterior femoral radiolucent lines merit continued observation. Patients with less preoperative motion were more likely to benefit from a high-flexion TKA.

Limitations of structural allograft in revision total knee arthroplasty.

UNLABELLED: Management of large bone defects in total knee arthroplasty (TKA) usually has involved modular prostheses with metal augments, structural allografts, and megaprostheses. We retrospectively reviewed the outcome of treatment of major bone defects for 74 patients (79 knees) who had revision TKAs with structural allografts; nine patients were lost to followup before 5 years, leaving 65 patients (70 knees, or 88%) followed for a minimum of 5 years or until revision or death. Medical records, radiographs, patient surveys, and correspondence were used for all data. Sixteen patients (22.8%) had failed reconstructions and underwent additional revision surgery; eight of the 16 were secondary to allograft failure, three were secondary to failure of a component not supported by allograft, and five were secondary to infection. In patients not requiring revision surgery, the Knee Society score improved from 49 preoperatively to 87 postoperatively. We observed revision-free survival of 80.7% (95% confidence interval, 71.7-90.8) at 5 years and 75.9% (95% confidence interval, 65.6-87.8) at 10 years. Our data support the selective use of structural allograft for large cavitary defects encountered during TKA. However, the rates of complications and reoperations suggest efforts to improve results or develop more durable alternative methods are warranted for these challenging reconstructions. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.