Background Surgical site infection (SSI) after acute hip fracture surgery is a devastating complication associated with increased suffering and mortality. The aim of the study was to investigate early SSI, sepsis, pneumonia and urinary tract infections over five years, before and after the implementation of the Safe Hands project.

Methods This was a single-centre observational study with a 5-year longitudinal design, investigating the effects of an infection-prevention intervention targeting the clinical care pathway of individuals with acute hip fracture. Statistical analyses were based on routinely collected patient outcome data comprising 3553 patients. The study conforms to the criteria of the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE).

Results The incidence of early SSIs decreased from 2.5% in years 1–2 to 1.1% in years 4–5. Similar results were observed for sepsis (2.7% to 1.3%) and urinary tract infections (14.2% to 4.2%). The multivariable regression results suggest that, for every observed year, the odds of early SSIs decreased. Male gender, procedure time, sepsis and preoperative skin damage increased the odds significantly.

Conclusions Our preventive bundle, based on partnership between researchers, managers and clinicians and a strong commitment to change from the involved professions, appear to be effective in reducing the frequency of potentially devastating SSIs and other hospital acquired infections after hip fracture surgery. The use of external and internal facilitators was crucial to enable individual and organisational learning and overcoming barriers to improvements.

Trial registration: Clinical Trials.gov ID: NCT02983136 Registered 6 December 2016—Retrospectively registered.