[Risk factors for infection in total knee artrhoplasty, including previously unreported intraoperative fracture and deep venous thrombosis].

PURPOSE: To carry out a statistical analysis on the significant risk factors for deep late infection (prosthetic joint infection, PJI) in patients with a knee arthroplasty (TKA).

METHODS: A retrospective observational case-control study was conducted on a case series of 32 consecutive knee infections, using an analysis of all the risk factors reported in the literature. A control series of 100 randomly selected patients operated in the same Department of a University General Hospital during the same period of time, with no sign of deep infection in their knee arthroplasty during follow-up. Statistical comparisons were made using Pearson for qualitative and ANOVA for quantitative variables.

RESULTS: The significant (p>0.05) factors found in the series were: Preoperative previous knee surgery, glucocorticoids, immunosuppressants, inflammatory arthritis.

INTRAOPERATIVE: prolonged surgical time, inadequate antibiotic prophylaxis, intraoperative fractures. Postoperative secretion of the wound longer than 10 days, deep palpable haematoma, need for a new surgery, and deep venous thrombosis in lower limbs. Distant infections cutaneous, generalized sepsis, urinary tract, pneumonia, abdominal.

CONCLUSIONS: This is the first report of intraoperative fractures and deep venous thrombosis as significantly more frequent factors in infected TKAs. Other previously described risk factors for TKA PJI are also confirmed.