This retrospective cohort study asked whether a 7-day course of oral antibiotics after discharge reduces periprosthetic joint infection in high-risk primary TKA and THA patients. It compared 90-day PJI rates across 2,181 arthroplasties performed from 2011 to 2016, before and after a formal extended prophylaxis protocol was introduced in January 2015.
Standard practice limits perioperative antibiotic prophylaxis to 24 hours after TJA — a threshold endorsed by the International Consensus on PJI and the 2017 CDC guidelines. For average-risk patients, that is probably appropriate. For high-risk patients, this study suggests it leaves a meaningful infection window open.
When you are consenting a patient with morbid obesity, diabetes, chronic kidney disease, autoimmune disease, active smoking, or MRSA colonization for primary TKA or THA, this paper supports adding a 7-day course of cefadroxil 500 mg twice daily at discharge. For MRSA carriers, substitute Bactrim DS or clindamycin.
The numbers matter for counseling: a diabetic patient with BMI ≥40 faces roughly a 1-in-10 chance of PJI in some series; this protocol brought that rate to zero in this cohort. That is a clinically meaningful difference, not just a statistical one.
The antimicrobial resistance concern is real and the authors acknowledge it. This is not a protocol for every patient, and the CDC explicitly recommends against routine extended prophylaxis. The evidence supports a selective, risk-stratified approach, not blanket use.
This retrospective cohort study asked whether a 7-day course of oral antibiotics after discharge reduces periprosthetic joint infection in high-risk primary TKA and THA patients. It compared 90-day PJI rates across 2,181 arthroplasties performed from 2011 to 2016, before and after a formal extended prophylaxis protocol was introduced in January 2015.
Standard practice limits perioperative antibiotic prophylaxis to 24 hours after TJA — a threshold endorsed by the International Consensus on PJI and the 2017 CDC guidelines. For average-risk patients, that is probably appropriate. For high-risk patients, this study suggests it leaves a meaningful infection window open.
When you are consenting a patient with morbid obesity, diabetes, chronic kidney disease, autoimmune disease, active smoking, or MRSA colonization for primary TKA or THA, this paper supports adding a 7-day course of cefadroxil 500 mg twice daily at discharge. For MRSA carriers, substitute Bactrim DS or clindamycin.
The numbers matter for counseling: a diabetic patient with BMI ≥40 faces roughly a 1-in-10 chance of PJI in some series; this protocol brought that rate to zero in this cohort. That is a clinically meaningful difference, not just a statistical one.
The antimicrobial resistance concern is real and the authors acknowledge it. This is not a protocol for every patient, and the CDC explicitly recommends against routine extended prophylaxis. The evidence supports a selective, risk-stratified approach, not blanket use.