OBJECTIVE To explore the risk factors for postoperative incision infections in the patients with open calcaneal fracture and observe the association with immune function and nutritional status.

METHODS A total of 120 patients with open calcaneal fracture who were treated in the Third Hospital of Hebei Medical University from May 2021 to Apr. 2023 were recruited as the research subjects and were divided into the infection group with 31 cases and the non-infection group with 89 cases according to the status of postoperative incision infection. The pathogens causing the infections were identified, multivariate logistic regression analysis was performed for the risk factors for the postoperative incision infections, and the immune function and nutrition indexes were observed and compared between the two groups.

RESULTS Totally 34 strains of pathogens were isolated from the 31 patients with postoperative incision infections, among which gram-negative bacteria. Univariate analysis showed that there were no significant differences in gender, body mass index, smoking history, causes of fracture, Sanders fracture classification, complication with hypertension and bone grafting between the infection group and the non-infection group. The proportion of patients aged more than 60 years old was higher in the infection group than in the non-infection group, the proportion of patients complicated with diabetes mellitus was higher in the infection group than in the non-infection group, the operation duration of the infection group was longer than that of the non-infection group(P < 0.05). Multivariate logistic regression analysis indicated that the age, complication with diabetes mellitus and operation duration were the risk factors for the postoperative incision infections in the patients with open calcaneal fractur. The CD₃⁺, CD₄⁺ and CD₄⁺/CD₈⁺ of the infection group were lower than those of the non-infection group, while the CD₈⁺ level of the infection group was higher than that of the non-infection group(P < 0.05). The levels of hemoglobulin (Hb), albumin (ALB) and prealbumin (PA) of the infection group were lower than those of the non-infection group(P < 0.05).

CONCLUSIONS The gram-negative bacteria are dominant among the pathogens isolated from the open calcaneal fracture patients with postoperative incision infections. There are a variety of risk factors for the postoperative incision infections. The patients with the incision infections show the decline of immune function and nutritional status.