Closed Incision Negative Pressure Wound Therapy vs Conventional Dry Dressings After Primary Knee Arthroplasty: A Randomized Controlled Study.

Background: The purpose of this study was to assess the effect of negative pressure wound therapy (NPWT) on quality of life (QoL), wound complications, and cost after primary knee arthroplasty.

Methods: A prospective analysis of 33 patients undergoing primary knee arthroplasty performed by 3 surgeons in one institution. The first 12 patients (3 bilateral and 9 unilateral) had conventional dry dressings (CDD) applied and cost of dressings was assessed. The other 21 patients all underwent bilateral knee arthroplasty and had either side randomized to receiving NPWT or CDD. Cost of dressings, wound complications, and QoL were compared.

Results: One patient had a reaction to the NPWT requiring readmission. Another had persistent wound drainage that required NPWT application. There were no wound issues in the remaining 31 patients. The average cost in the first 12 patients was Australian dollar $48.70 with an average of 1.5 changes on ward. In the 21 patients receiving both dressings, the average cost for CDD was less (Australian dollar $43.51 vs $396.02, P ≤ .011, effect size [ES] = 1.06). When comparing QoL factors, wound leakage (0.14 vs 0.39 P = .019, ES = 1.02), and wound protection (0.16 vs 0.33, P = .001, ES = 0.021) were better in the NPWT group. There was no other significant difference in QoL factors. The average number of changes on the ward was less for the NPWT group (1.19 vs 1.38, P = .317, ES = 1.02).

Conclusion: We found no benefit in wound healing or cost with NPWT post knee arthroplasty. There was some benefit in NPWT QoL factors less wound leakage and better protection.