Among 1179 PJIs treated during the study period, 15 (1%) PJIs were due to C avidum (14 classified as late chronic and 1 as early postoperative). They involved only obese patients with hip arthroplasties (median age 65 years, body mass index 35 kg/m2). Twelve patients’ PJIs developed after primary hip arthroplasty. Thirteen patients’ last clean operation had used an anterior approach. Fourteen preoperative joint aspirate cultures yielded C avidum. The 14 chronic PJIs were treated with 1-stage exchange arthroplasty, the acute case with excision synovectomy. Antibiotic therapy was administered for 12 [6-13] weeks, intravenously for 4 [2-6] weeks. The most used first-line agents were intravenous clindamycin (n = 8) or cefazolin (n = 6). After median follow-up of 27 [3-136] months, 1 relapse occurred. Compared to C acnes PJI patients, those with C avidum PJIs were significantly younger, had higher body mass indices, had only hip involvement, and had more frequent anterior surgical approach. C acnes PJIs were more frequent after revision arthroplasty.