Methods

Data were collected prospectively for all cases of instrumented thoracic and lumbar spine surgery undertaken by the senior author (DB) from 01/10/2008 to 1/10/2010. Variables recorded included patient factors (age, co-morbidities, drug history) and operative factors (type of operation, duration of operation, elective/emergency, in hours/out of hours, consultant/junior, perioperative antibiotic administration). Routine povidone-iodine application commenced on 1/06/2009. Surgical site infection was defined as wound infection confirmed on wound swab or blood cultures. Comparison was made between patients receiving povidone-iodine intraoperative wound irrigation and those who did not using Fisher's exact test.