Development and Validation of a Preoperative Surgical Site Infection Risk Score for Primary or Revision Knee and Hip Arthroplasty. (21st September 2016)

• Record Type: Journal Article
• Authors: Everhart, Joshua S.; Andridge, Rebecca R.; Scharschmidt, Thomas J.; Mayerson, Joel L.; Glassman, Andrew H.; Lemeshow, Stanley
• Is Part Of: Journal of bone and joint surgery. Volume 98:Number 18(2016)
• Publication Date: 2016-09-21
• Subjects: Bones -- Surgery -- Periodicals; Joints -- Surgery -- Periodicals; Orthopedics -- Periodicals; Orthopedics; General Surgery; Bone Diseases; Joint Diseases; Bones -- Surgery; Joints -- Surgery; Orthopedics; Bot (anatomie); Gewrichten; Chirurgie (geneeskunde); Periodicals; Electronic journals; Periodicals; 617.47005
• DOI: 10.2106/JBJS.15.00988
• Languages: English
• ISSNs: 0021-9355

Abstract

Abstract : Background: Surgical site infection (SSI) is a major complication following total joint arthroplasty. Host susceptibility to infection has emerged as an important predictor of SSI. The purpose of this study was to develop and validate a preoperative SSI risk-assessment tool for primary or revision knee and hip arthroplasty. Methods: Data for 6, 789 patients who underwent total joint arthroplasty (from the years 2000 to 2011) were obtained from a single hospital system. SSI was defined as a superficial infection within 30 days or deep infection within 1 year. Logistic regression modeling was utilized to create a risk scoring system for a derivation sample (n = 5, 789; 199 SSIs), with validation performed on a hold-out sample (a subset of observations chosen randomly from the initial sample to form a testing set; n = 1, 000; 41 SSIs). Results: On the basis of logistic regression modeling, we created a scoring system to assess SSI risk (range, 0 to 35 points) that is the point sum of the following: primary hip arthroplasty (0 points); primary knee (1); revision hip (3); revision knee (3); non-insulin-dependent diabetes (1); insulin-dependent diabetes (1.5); chronic obstructive pulmonary disease (COPD) (1); inflammatory arthropathy (1.5); tobacco use (1.5); lower-extremity osteomyelitis or pyogenic arthritis (2); pelvis, thigh, or leg traumatic fracture (2); lower-extremity pathologic fracture (2.5); morbid obesity (2.5); primary bone cancer (4); reaction to prosthesis in the last 3 years (4); and history of staphylococcal septicemia (4.5). The risk score had good discriminatory capability (area under the ROC [receiver operating characteristic] curve = 0.77) and calibration (Hosmer-Lemeshow chi-square test, p = 0.34) and was validated using the independent sample (area under the ROC curve = 0.72). A small subset of patients (5.9%) had a >10% estimated infection risk. Conclusions: The patient comorbidities composing the risk score heavily influenced SSI risk for primary or revision knee and hip arthroplasty. We believe that infection risk can be objectively determined in a preoperative setting with the proposed SSI risk score.