OSF HEALTHCARE A fresh, new face. Same great heart. We've built a new home for your OSF HealthCare primary care services in Sheffield. Now known as OSF HealthCare - Medical Group, we are serving patients at 240 N. Mason St. in Sheffield. To schedule an appointment, please call our office at (815) 454-2811 or contact us online through OSF MyChart. OSF HEALTHCARE OSF HEALTHCARE A fresh, new face. Same great heart. We've built a new home for your OSF HealthCare primary care services in Sheffield. Now known as OSF HealthCare - Medical Group, we are serving patients at 240 N. Mason St. in Sheffield. To schedule an appointment, please call our office at (815) 454-2811 or contact us online through OSF MyChart. OSF HEALTHCARE