Knee flexion after total knee arthroplasty reduces blood loss.
OBJECTIVE
Extensive blood loss after total knee arthroplasty (TKA) may be a potential problem since it leads to anaemia, increased need for transfusion and prolonged hospitalization. Aim of this study was to investigate the effects of postoperative knee flexion after TKA on blood loss and the need for transfusion.


METHODS
One hundred consecutive patients undergoing primary TKA from 2012 to 2013 were randomizely divided into two groups. In one group, the knee was extended for the first 6 h after surgery, whereas in the other was flexed at 90° for the same time. Two doses of endovenous tranexamic acid were administered in all subjects. Patients were homogeneous for all the possible confounding factors.


RESULTS
Calculated blood loss was 846 ± 197 (ml) in the flexion group and 1,242 ± 228 (ml) in the extension group (p < 0.05). Drop of haemoglobin levels at 24 h in the study group and the control group was 1.9 ± 0.8 (g/dl) and 3.0 ± 0.5 (g/dl), respectively (p < 0.01). Drop of haematocrit at 24 h was 4.5 ± 0.2 (%) in the flexion group and 6.7 ± 0.3 (%) in the extension group (p < 0.05). Blood transfusion was necessary in 5 patients in the control group and was not necessary in any patient of the study group. Average knee flexion at day 7 was 105° ± 4° in the flexion group and 98° ± 7° in the extension group.


CONCLUSIONS
Knee flexion at 90° after TKA, associated with the intraoperative use of tranexamic, acid is an effective method to reduce blood loss and the need for blood transfusion. The routine use of the present protocol is effective in reducing social costs and length of hospitalization of TKA procedures.
Department of Medicine and Science for Health, Molise University, Via De Sanctis 1, Campobasso, Italy.
Alfredo Schiavone
AS
Panni
Simone
S
Cerciello
Michele
M
Vasso
Chiara
C
Del Regno
D000368:Aged; D000933:Antifibrinolytic Agents / Q000627:therapeutic use; D019645:Arthroplasty, Replacement, Knee; D001803:Blood Transfusion; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D056888:Patient Positioning; D019106:Postoperative Hemorrhage / Q000517:prevention & control*; D016059:Range of Motion, Articular; D014148:Tranexamic Acid / Q000627:therapeutic use; D014945:Wound Healing
D000933:Antifibrinolytic Agents; D014148:Tranexamic Acid