Incidence and risk factors of delayed wound healing in patients who underwent unicompartmental knee arthroplasty

Unicompartmental knee arthroplasty (UKA) has been proven as an ideal alternative surgical procedure to treat symptomatic isolated knee osteoarthritis, and recently this technique has gained its popularity. However, postoperative complications would inevitably compromise the effectiveness and patients' satisfaction. The objective of this study is to demonstrate the incidence and risk factors of delayed wound healing (DWH) after UKA. This retrospective cohort study was conducted from February 2021 to May 2022 and a total of 211 patients were enrolled. Demographic characteristics, operation‐related variables, and laboratory indexes were extracted. Receiver operating characteristic analysis was performed to detect the optimum cut‐off value for continuous variables. Univariate and multivariate logistic regression analysis was performed to demonstrate the risk factors of DWH. There were 155 female and 56 male patients with an average age of 64. 6 ± 6.9 years included in this study. After 6.6 ± 4.9 months’ follow‐up, 12 cases of DWH were observed which indicated an incidence of DWH of 5.7%, mean wound healing duration for 12 patients was 43.1 ± 19.3 days. In the univariate analysis, age > 62.5 years, postoperative hospital stay < 5.5 days, surgical incision < 10.5 cm, barbed suture, body mass index (BMI) > 32.0 kg/m(2), operation duration > 102.5 minutes, intraoperative blood loss > 102.5 mL, preoperative white blood cell count > 5.95*10(9)/L, preoperative seroglobulin (GLB) > 29.6 g/L, postoperative total protein < 63.4 g/L, postoperative serum albumin < 36.4 g/L, and postoperative GLB > 26.8 g/L were significantly different between patients with and without DWH (P < .05). In final multivariate logistic analysis, results showed that intraoperative blood loss > 102.5 mL (odds ratio [OR], 3.09; P = .001), postoperative hospital stay < 5.5 days (OR, 1.74; P = .014), surgical incision < 10.5 cm (OR, 1.67; P = .000), and BMI > 32.0 kg/m(2) (OR, 4.47; P = .022) were independent risk factors for DWH. DWH prolongs hospital stay in UKA patients and increases healthcare expenditure; also affected the implementation schedule of postoperative functional exercise plans. Surgeons should identify patients at risk, meanwhile, make timely and correct clinical interventions to decrease the incidence of this complication.