colonization of the anterior and lateral thigh.

Aims: Of growing concern in arthroplasty is the emergence of atypical infections, particularly (formerly ) sp. infections. Currently, the dermal colonization rate of about the hip is unknown. Therefore, the aim of this study was to investigate colonization rates of sp. at locations approximating anterior and posterolateral approaches to the hip joint.

Methods: For this non-randomized non-blinded study, 101 adult patients scheduled for hip or knee surgery were recruited. For each, four 3 mm dermal punch biopsies were collected after administration of anaesthesia, but prior to antibiotics. Prebiopsy skin preparation consisted of a standardized preoperative 2% chlorhexidine skin cleansing protocol and an additional 70% isopropyl alcohol mechanical skin scrub immediately prior to biopsy collection. Two skin samples 10 cm apart were collected from a location approximating a standard direct anterior skin incision, and two samples 10 cm apart were collected from a lateral skin incision (suitable for posterior, direct-lateral, or anterolateral approaches). Samples were cultured for two weeks using a protocol optimized for .

Results: A total of 23 out of 404 cultures (collected from 101 patients) were positive for a microorganism, with a total of 22 patients having a positive culture (22%). Overall, 15 of the cultures in 14 patients were positive for sp. (65%), of which comprised the majority (n = 13; 87%). Other isolated microorganisms include coagulase-negative (n = 6), (n = 1), and (n = 1). Of all positive cultures, 15 were obtained from the anterior location (65%), of which seven (60%) were from the most proximal biopsy location. However, these findings were not statistically significant (anterior vs lateral, p = 0.076; proximal vs distal, p =0.238).

Conclusion: Approximately 14% (14/101) of the patients demonstrated a positive colonization about the hip, the majority anteriorly. Given the high colonization rate of , alternative skin preparations for total hip arthroplasty should be considered. Cite this article: 2020;102-B(7 Supple B):52-56.