HealthCareAtlasUSA

This site republishes official CMS/Medicare Care Compare data. It is not medical advice and does not recommend any specific hospital or treatment — for medical decisions, talk to a doctor.

Doctors / CA

MATHIAS MASEM, MD

ORTHOPEDIC SURGERY

Medical school: UNIVERSITY OF MINNESOTA MEDICAL SCHOOL

Graduated: 1975

Offers telehealth

NPI: 1508810938

Practice Locations (4)

MATHIAS MASEM MD

80 GRAND AVE, SUITE 600

OAKLAND, CA 946123744

5107630884

UCSF MEDICAL GROUP BUSINESS SERVICES

1600 DIVISADERO ST

SAN FRANCISCO, CA 941153010

4154761000

UNIVERSITY OF CALIFORNIA SAN FRANCISCO

2330 POST ST

SAN FRANCISCO, CA 941153465

4154764029

UCSF MEDICAL GROUP BUSINESS SERVICES

400 PARNASSUS AVE

SAN FRANCISCO, CA 941432202

Source: CMS National Downloadable File, September 2026.