Tissue adhesive is a sterile glue that exists in liquid form. Its chemical composition (2-octylcyanoacrylate) could rapidly polymerize in contact with hydroxyl ions of the blood and water. The resultant polymer is biodegradable within about ten days and bacteriostatic to gram-positive bacteria .
Incision closure can be a key factor in early rehabilitation of TKA. Skin sutures and staples have proven to have satisfying safety in clinical practise [4, 8]. However, the advent of ERAS promotes more earlier rehabilitation and less hospital stays following TKA, which draws two additional demand for incision closure. One is more cosmetic appearance, another one is less incision care, including regular disinfectant and removal of sutures or staples.
To cater to fast rehabilitation and cosmetic need, some surgeons introduced the tissue adhesive in orthopedic surgeries [17–19]. But the clinical study on the comparison with subcuticular suture in joint surgery was rare [10, 20–22].
Roumeliotis and Graham reported that tissue adhesive with subcuticular suture application was a viable option for skin closure after lower limb arthroplasty and can reduce the incidence of prolonged wound discharge . However, their study had several obvious limitations. Firstly, the study was retrospective and two groups of patients came from different time periods. Secondly, the incidence and duration of prolonged wound exudate were extracted from the medical records, but the bias in the subjectivity and reliability of medical record can’t be controlled properly. Thirdly, the study enrolled the patients undergoing total hip or knee arthroplasty and TKA accounted for only a third.
In another similar randomized and self-controlled study, Gromov et al enrolled 29 patients undergoing simultaneous bilateral TKA . They found that tissue adhesive plus skin staples could reduce the number of dressing changes after surgery, but not change the appearance or healing of the wound at postoperative 3 weeks. Their study only analyzed the wound drainage during the first postoperative 72 hours and didn’t compared the medical costs and satisfaction rate between two groups.
Although some surgeons have successfully applied the tissue adhesive in TKA, it is still too reckless to completely replace skin sutures or staples by tissue adhesive for skin closure. One prospective randomized and controlled clinical trial compared 2-octylcyanoacrylate, subcuticular suture and skin staples for skin closure following hip and knee replacement. They found that tissue adhesive in knee replacement was more directly associated with prolonged wound discharge . So we adopted the tissue adhesive as the supplement to, not substitute for subcuticular closure in this study.
This was the first study on comparing the clinical outcome, medical cost and patient preference of tissue adhesive plus subcuticular sutures with just subcuticular sutures in simultaneous bilateral TKA. The prospective and self-controlled clinical trial has eliminated the patients’ personalized characteristics, such as BMI, individual healing abilities and systemic disease.
In this study, we found that tissue adhesive combining with subcuticular sutures could effectively reduce postoperative wound drainage with the similar medical cost and ROM in TKA. The application of tissue adhesive and subcuticular sutures might be a relatively ideal method of skin closure for fast-recovery TKA.
Although the mere subcuticular sutures could provide the patients with superior cosmetic appearance and enough resistance to skin tension during knee flexion, it still left the problem of incision drainage unresolved [24–26]. In this study, just the application of subcuticular sutures in TKA was more likely to be the dragging reason of delayed discharge, especially in obese patients. Prolonged fat liquefaction or aseptic exudation could form a flow channel, where microorganisms can cause superficial or even deep infections. The tissue adhesive could isolate the internal incision and prevent the outside microorganisms from invading through the unhealed incision. Several studies also approved this view. As El-Gazzar and Gromov et al reported, when the tissue adhesive worked as an adjunct to skin staples after TKA, it could decrease post-operative wound drainage [11, 14]. Easier care of incision and fewer need of physicians could facilitate the patients’ early daily life greatly. The patients can go straight home from the hospital without having to go to the rehabilitation institute or clinic just for incision observation. With the similar medical costs during the hospital stay, patients preferred the combination of tissue adhesive and subcuticular suture than the control group. If the incision-related costs after discharge were took into consideration, perhaps the additional material cost of the tissue adhesive would be offset or even exceed. The use of tissue adhesive could increase the patients’ satisfaction and confidence in surgery, which was also found in other studies [10, 27].
The risk of allergy to tissue adhesive can’t be ignored, while we didn’t find any allergic contact dermatitis in this cohort. Several studies reported that the rate of allergy to tissue adhesive ranged from 0.5–1.7% [28, 29]. Another limiting factor for tissue adhesive was the additional costs. Notice, however, that the overall costs remain unchanged or even reduced when using tissue adhesive [20, 21].
The present study also had several important limitations. Firstly, the sample size and follow-up were small and short. Larger sample size and longer follow up are needed to analyze the incidence of infection and readmission. In fact, given that the prospective controlled clinical trial and incision healing period, it has already applied enough information and data. Secondly, the incision evaluation scales had subjective bias. Fortunately, the evaluation scores between the two observers had NEARLY PERFECT RELIABILITY. Thirdly, because the price of tissue adhesive varied in different regions and the incision-related costs after discharge were not included, the overall medical cost in this study might not applicable to other institutes. Fourthly, the patients undergoing simultaneous bilateral TKA generally have fewer medical disease when compared with the patients undergoing unilateral TKA, which might interfere with the incision healing.