Various strategies of preventing wound complications have already been developed, and the core goal of these strategies is to improve the prognosis and survival qualities of patients with TJA. However, the effect of application of diverse wound dressings remain unclear. Some present studies found that iNPWT has an advantage on wound healing [5, 21]. A previous systematic review [22] evaluating the prophylactic use of iNPWT for wound complications in several surgical fields such as laparotomy for abdominal, coronary arteries bypass grafting, and lymphadenectomy. It considered that incisional negative pressure wound therapy dressing seemed to be an effective prophylactic measure in decreasing complications and reoperation rate and be regarded as potentially cost saving especially in high-risk patients. However, there was limited studies on the application of iNPWT in orthopedic surgery. Newman et al [21] conducted a RCT on application of iNPWT compared with silver-impregnated occlusive dressing for revision total hip or knee arthroplasty in patients at high risk for infection. This study found that iNPWT may decrease the rate of postoperative wound complications. Pachowsky et al [23] conducted a RCT about iNPWT’s influence on the development of postoperative seromas in the wound area. The result of this RCT demonstrated that iNPWT may decrease development of postoperative seromas. One cost-effectiveness analysis [24] of iNPWT on primary hip and knee replacements showed that the efficacy of iNPWT in terms of improving cost-effectiveness and comfort for both patients and caregivers was irrefutable. One retrospective study reported that there was significant difference in overall complications between iNPWT and conventional wound dressing. However, the finding was not statistically significant when each individual complication was compared separately[25]. Another study found that iNPWT may increase the Occurrence of blisters, which resulted from trial stopping prematurely [18]. Gillespie et al [11] reported a RCT on iNPWT compared with hydrocolloid dressing for patients undergoing THA. This study found that the iNPWT patients had less surgery site infection indicators but experienced more other postoperative complications and its costs were higher. A systematic review, karlakki et al [26] demonstrated 9 studies reporting the application of iNPWT in orthopedic surgery, five of which were randomized controlled trials (RCTs). Only 3 RCTs involve either THA or TKA. Therefore, there was a lack of high level evidence in the field of adult arthroplasty concerning the application of iNPWT. The benefit of iNPWT after TJA was uncertain.
This meta-analysis including 5 RCTs and 1 prospective cohort study aims to evaluate whether there is difference between iNPWT and conventional wound dressing on wound healing in patients who received TJA. Results from this study showed that applying incisional negative pressure wound therapy dressing may decrease the postoperative dressing changes. It seems to demonstrate that iNPWT may reduce the drainage.
The complications including overall, minor and major were the primary outcome in our study. The occurrence of complications was a sign of wound status, even result in failure of surgery. Our meta-analysis defined complication as minor or major. Some studies indicated that iNPWT had an effect on decreasing complications but there were some studies reporting the opposite efficacy[18, 21, 23]. In this meta-analysis, no difference in overall, minor and major complications were found after TJA.
The rate of infection was also an important outcome in this study. Severe infection was associated with adverse effects including failure of surgery, difficulty of wound healing, and cost. Hence, infection control was desirable. Previous study reported that the iNPWT had less surgery site infection[23]. This was consistent with our study but these differences were no statistically significantly different.
With regard to the rate of reoperation, in our meta-analysis, four included studies reported that the rate of reoperation in iNPWT group was lower[9, 18–20]. However, there were no statistically significant difference. In addition, two included study reported that the reduction in the length of the stay for application of iNPWT, although measurable, was not statistically significant difference.
The limitations of this meta-analysis included that: firstly, there was selection bias in studies (2/5), which did not state the method of randomization. The potential bias of selective reporting due to the stopped prematurely may also influenced the true effect measurement. Secondly, the number of included studies and sample sizes in this meta-analysis was small, which may lead to an imprecise effect estimation. Finally, subgroup analysis could not be performed for any source of heterogeneity, which may impact the true effect of clinical outcomes.