Antibiotic-loaded bone cement reduces deep infection rates for primary reverse total shoulder arthroplasty: a retrospective, cohort study of 501 shoulders.

BACKGROUND: Deep infection after primary reverse total shoulder arthroplasty is a devastating event and has an increased incidence compared with anatomic total shoulder arthroplasty. Recent reports in the hip and knee arthroplasty literature suggest that antibiotic-loaded bone cement may lower infection rates for primary arthroplasties. We conducted a retrospective cohort study to evaluate the effect of antibiotic-loaded bone cement vs plain bone cement on the prevention of deep infection after primary reverse total shoulder arthroplasty. MATERIALS AND METHODS: Four surgeons from their respective facilities participated in the retrospective cohort data collection. From 1999 to 2008, 501 consecutive primary reverse total shoulder arthroplasties were performed. Patients with revision of failed previous arthroplasties were excluded, and patients with any other previous shoulder procedure were included. Two groups were examined in this retrospective cohort: In group 1 (265 shoulders), the cement used for humeral fixation did not have antibiotics; in group 2 (236 shoulders), antibiotic-impregnated bone cement containing tobramycin, gentamycin, or vancomycin/tobramycin was used for fixation. RESULTS: At an average postoperative follow-up of 37 months, no deep infection had developed in the 236 shoulders in group 2, whereas a deep infection had developed in 8 of the 265 shoulders (3.0%) in group 1. This difference between the groups was significant (P < .001). CONCLUSIONS: Antibiotic-impregnated bone cement was effective in the prevention of postoperative deep infection after primary reverse total shoulder arthroplasty during short-term follow-up.

Radiostereometric and Radiographic Analysis of Glenoid Component Motion After Total Shoulder Arthroplasty.

Aseptic glenoid component loosening is a common cause of total shoulder arthroplasty (TSA) failure, but early detection is difficult because pain often appears late and radiolucent lines are of uncertain significance. This study sought to answer the following questions: (1) What types of glenoid component motion may be observed during the first 3 years following implantation?; (2) Is the appearance of radiolucent lines around the glenoid component a reliable indicator of component motion?; and (3) Are clinical outcomes correlated with early glenoid component motion within the first 3 years after TSA? Eleven patients (mean age, 60.6 years) underwent TSA using a cemented, all-polyethylene glenoid component with tantalum bead implantation. Clinical outcomes (American Shoulder and Elbow Surgeons [ASES] score, visual analog scale [VAS] pain score, and range of motion) were compared pre- and postoperatively, and radiolucencies were graded according to the criteria of Lazarus et al. Patients were evaluated using radiostereometric analysis at 6 months and 1, 2, and 3 years postoperatively to measure component micromotion in translation and rotation. At a mean follow-up of 50.2 months, mean ASES score had improved from 30.3 to 81.3 (P<.001), mean VAS pain score had improved from 8 to 1 (P<.001), active forward flexion had improved from 109° to 155° (P=.001), active external rotation had improved from 28° to 54° (P=.003), and internal rotation had improved from the level of the sacrum to L3 (P=.002). Radiolucencies were detected around none of the components at 1 year, 6 components at 2 years, and 5 components at 3 years, and these radiolucencies were mostly found around components that experienced high levels of rotational motion.