Bleeding in TKA: posterior stabilized vs. cruciate retaining.
BACKGROUND
Posterior-stabilized (PS) and cruciate-retaining (CR) total knee arthroplasties (TKA) are both successfully used for treatment of end-stage osteoarthritis. The choice of constraint depends on knee deformity and stability as well as most importantly surgeon preference. The aim of this study was to compare the amount of blood loss and required transfusions following TKA with the two different designs.


METHODS
In a retrospective approach, 473 patients undergoing TKA were included (240 CR and 233 PS from a single manufacturer). Demographics at base line were comparable between both groups. Blood loss [red blood cell (RBC) loss] was calculated after documentation of pre- and postoperative hematocrit levels at discharge. Transfusion requirements were recorded. Statistical analysis was done using Mann-Whitney U test.


RESULTS
The calculated blood loss (RBC loss) at discharge was 548 ± 216 ml in the PS group compared with 502 ± 186 ml in the CR group (p = 0.032). There were no differences in the transfusion requirements between both groups (PS 0.41 vs. CR 0.37, p = 0.39).


CONCLUSIONS
The blood loss was significantly higher in the PS group. This may be due to the box preparation that exposes more cancellous femoral bone, which may add to postoperative bleeding. The differences remain, however, small, as they did not lead to a significantly higher transfusion rate with PS TKA.
Department of Diagnostic and Interventional Radiology, University Hospital Mainz, Langenbeckstr. 1, 55131, Mainz, Germany.
Aline
A
Mähringer-Kunz
Turgay
T
Efe
Susanne
S
Fuchs-Winkelmann
Karl F
KF
Schüttler
Jürgen R
JR
Paletta
Thomas J
TJ
Heyse
D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D020370:Osteoarthritis, Knee / Q000601:surgery*; D016119:Posterior Cruciate Ligament / Q000601:surgery*; D019106:Postoperative Hemorrhage; D012189:Retrospective Studies