This single-surgeon, single-blinded RCT tested whether irrigating the subcutaneous layer with 0.05% chlorhexidine gluconate before deep dissection reduces C acnes contamination in primary total shoulder arthroplasty. 126 patients were randomized to CHG or saline lavage, with five intraoperative cultures taken per case. The primary endpoint was the rate of positive deep C acnes cultures.
The clinical takeaway is concrete: add a 100 mL 0.05% CHG lavage of the exposed subcutaneous layer after skin incision and before deep dissection during primary TSA.
The mechanistic model to remember is that C acnes lives intradermally, so preoperative skin prep alone cannot eradicate it. The organism is dragged into the deep field during dissection, and treating the subcutaneous layer intercepts that transfer.
Why the effect is time-dependent matters clinically. Superficial cultures taken right after lavage were unchanged, but deep cultures later in the case were reduced, arguing for a bactericidal mechanism that needs dwell time.
Keep the appraisal honest. This is a single-surgeon Level I trial funded in part by the irrigation manufacturer, and it measured culture positivity, not actual PJI rates. A lower culture load is a plausible surrogate, but the link to fewer clinical infections remains unproven.
This single-surgeon, single-blinded RCT tested whether irrigating the subcutaneous layer with 0.05% chlorhexidine gluconate before deep dissection reduces C acnes contamination in primary total shoulder arthroplasty. 126 patients were randomized to CHG or saline lavage, with five intraoperative cultures taken per case. The primary endpoint was the rate of positive deep C acnes cultures.
The clinical takeaway is concrete: add a 100 mL 0.05% CHG lavage of the exposed subcutaneous layer after skin incision and before deep dissection during primary TSA.
The mechanistic model to remember is that C acnes lives intradermally, so preoperative skin prep alone cannot eradicate it. The organism is dragged into the deep field during dissection, and treating the subcutaneous layer intercepts that transfer.
Why the effect is time-dependent matters clinically. Superficial cultures taken right after lavage were unchanged, but deep cultures later in the case were reduced, arguing for a bactericidal mechanism that needs dwell time.
Keep the appraisal honest. This is a single-surgeon Level I trial funded in part by the irrigation manufacturer, and it measured culture positivity, not actual PJI rates. A lower culture load is a plausible surrogate, but the link to fewer clinical infections remains unproven.