Long-duration immediate postoperative knee flexion positioning results in better functional outcomes after total knee...

This study aimed to evaluate the effects of affected knee flexion for 24 vs. 72 hours on blood loss, pain, range of motion, and functional outcomes after total knee arthroplasty.

The present study included 46 participants with a mean age of 64.33 ± 6.70 years. The affected knee of the first 23 participants, based on the order of operations, was positioned at 70° flexion for 24 hours, and the knee of the next 23 participants was positioned at 70° flexion for 72 hours. Participants were evaluated before the operation and on postoperative day 3 and week 6. Pain, edema, range of motion, time up and go test scores, and Western Ontario McMaster Universities Arthritis Index scores, hemoglobin, and hematocrit were measured before the operation and on postoperative at day 3 and week 6.

We found that the calculated blood loss was 575.07 ± 282.44 and 578.39 ± 297.11 mL in patients who underwent short- and long-duration flexion positioning, respectively (p = 0.921). The active flexion angles at postoperative week 6 were 83.61° ± 22.03° and 105.91° ± 13.06° in the short- and long-duration flexion groups, respectively (p < 0.01). Furthermore, the Western Ontario and McMaster Universities Arthritis Index scores at postoperative week 6 were 35.52 ± 24.71 and 17.17 ± 15.37 in the short- and long-duration flexion groups, respectively (p < 0.01).

Long-duration flexion positioning after total knee arthroplasty may lead to better middle-term flexion range of motion and physical function scores than short-duration flexion positioning.