Table 5.
Descriptive characteristics of surgery duration (minutes), tourniquet use, and postsurgical hemoglobin for five different types of knee replacement implants.
| n |
Surgery durationa
Mean (SD) |
Tourniquet useb
% (n) |
Bleeding, mL Mean (SD) |
Hemoglobin, g/Lc |
Postoperative length of stay Mean (SD) |
||
|---|---|---|---|---|---|---|---|
| Day 0, 20:00 Mean (SD) |
Day 4 Mean (SD) |
||||||
| Sigma | 43 | 93.6 (20.0) | 11.6% (5) | 381 (172) | 107.9 (11.7) | 101.4 (15.0) | 9.60 (2.89) |
| AGC | 34 | 87.8 (20.6) | 26.5% (9) | 291 (165) | 108.4 (10.9) | 101.0 (12.1) | 8.74 (1.68) |
| Other implants: | 23 | 110.7 (27.7) | 30.4% (7) | 343 (215) | 103.7 (12.5) | 93.8 (11.5) | 8.91 (2.21) |
| LCS | 14 | 105.4 (21.1) | 50.0% (7) | 318 (192) | 100.4 (9.2) | 91.1 (11.5) | 8.29 (2.16) |
| Scorpio NRG | 5 | 104.0 (5.5) | 0% | 470 (311) | 110.0 (4.9) | 99.4 (8.5) | 10.80 (1.64) |
| NexGen | 4 | 137.5 (49.9) a | 0% | 275 (126) | 107.0 (24.8) | 96.5 (14.2) | 8.75 (2.06) |
Note. Italicized text represents the 3 types of implants grouped together as “other implants.” Implant types did not differ with respect to bleeding, length of postoperative hospital stay, creatinine values (not shown), or CRP values (not shown).
aSurgery duration differed significantly by implant type (p < .001). In post hoc testing, the Sigma (p = .014) and AGC (p = .001) implants had significantly shorter surgery durations than the other three implants. One patient with a NexGen implant had a surgery duration of 210 minutes; a sensitivity analysis excluding this patient yielded similar omnibus results (p = .004), and the remaining NexGen implants still had a mean surgery duration of 113.3 (SD 15.3) minutes.
bTourniquet was used with the LCS more often than with the other implants (p = .009).
cOn the night of the surgery, hemoglobin values did not differ by implant type. However, on postoperative Day 4, the more common implants (Sigma and AGC) were associated with higher hemoglobin values than the other implants (p = .020).