Can Addition of Doxycycline Perioperatively Reduce Propionibacterium Acnes in Shoulder Arthroplasty?

The purpose of this study is to investigate antibiotic treatment to target bacteria about the shoulder. This bacteria, Propionibacterium acnes, is detected in many revision shoulder surgeries and is thought to contribute to periprosthetic joint infections, pain, and failure of total shoulder arthroplasty as well as other shoulder surgeries. This study is investigating adding an FDA approved antibiotic that is commonly used for treatment of this bacteria and many common infections. The investigators will take intraoperative cultures to look for the presence or absence of specific bacteria. The investigators are conducting this trial to see if adding another antibiotic to specifically target this common bacteria found around the shoulder will be effective.

Patients undergoing total and reverse shoulder arthroplasty for primary glenohumeral arthritis will be invited to participate in this study if patients meet inclusion and exclusion criteria. Patients will be randomized to receive either standard perioperative antibiotics with cefazolin or to the treatment group to receive doxycycline in addition to cefazolin. Patients will then undergo routine surgical treatment. 3 cultures from the superficial tissue, dermis, and glenohumeral joint will be taken and cultured for 14 days to detect any bacterial growth.

All patients will receive standard perioperative antibiotics with 2g of cefazolin within 1 hour of incision. The control group will not receive any further antibiotic treatment.

All patients will receive standard perioperative antibiotics with 2g of cefazolin within 1 hour of incision. The treatment group will receive 100mg of doxycycline IV in addition to cefazolin within 1 hour of incision.

The treatment group will receive 100mg of doxycycline IV in addition to cefazolin within 1 hour of incision for total shoulder arthroplasty.

Intraoperative cultures will be taken from all study participants and tested for detection of bacteria. These cultures were held for 14 days and tested for aerobic and anaerobic bacteria. Reported data are presented for the number of participants with a positive bacteria culture from the intraoperative samples.

Inclusion Criteria: Patients undergoing primary total shoulder arthroplasty at Rush University Medical Center Exclusion Criteria: Patients with prior shoulder surgery of any kind Patients with a known infection or history of infection with clinical signs such as elevated erythrocyte sedimentation rate, C-reactive protein, positive culture aspiration Patients with a known allergy to doxycycline Patients with a known allergy to cefazolin or penicillin