Browse Health
License & Identifications

A medical license is required for a doctor to practice medicine in a particular state. Requirements vary by state but most require, at a minimum, post-graduate training in the doctor’s specific specialty. An NPI number is a national identifier unique to an individual health care provider and is managed by the Center for Medicare & Medicaid Services (CMS).

Patient Reviews

Patient comments (9)

The overall average patient rating of Dr. Denis O'Brien is Good. Dr. O'Brien has been reviewed by 11 patients who have provided 9 comments. The rating is 3.5 out of 5 stars.

Patient Ratings
Ease of Appointment 4.5
Promptness 4.1
Courteous Staff 4.3
Accurate Diagnosis 3.7
Bedside Manner 3.8
Spends Time with Me 3.3
Follows Up After Visit 3.5

Specialties & Research

  • He has special expertise in 5 areas:
  • Hip Osteoarthritis
  • Hip Surgery (Hip Replacement Arthroplasty)
  • Knee Osteoarthritis
  • Knee Surgery (Knee Replacement Arthroplasty)
  • Sports Medicine

Education & Awards

Dr. O'Brien graduated from Georgetown University, Washington. He has 2 awards.

Castle Connolly's Top Doctors™ (2012 - 2013)
Patients' Choice Award (2013)


Dr. O'Brien has 2 hospital affiliations:

  • Montgomery General Hospital Inc 
  • Howard County General Hospital 

Similar doctors nearby

Dr. Sheldon Mandel

Orthopaedic Surgery
40 years experience
Olney, MD

Dr. Douglas Murphy

Orthopaedic Surgery
22 years experience
Olney, MD

Dr. Mohit Bhatnagar

Orthopaedic Surgery
23 years experience
Olney, MD

Dr. Charles Mess

Orthopaedic Surgery
47 years experience
Olney, MD

Dr. Alan Nagel

Orthopaedic Surgery
25 years experience
Olney, MD

Dr. Sanjog Mathur

Orthopaedic Surgery
28 years experience
Olney, MD
Search All Similar Doctors
Additional Information
Dr. Denis Peter O'Brien MD is a male Orthopaedic Surgeon, has 28 years of experience and practices in Orthopaedic Surgery and Surgery.
Where does Dr. Denis P. O'Brien practice?
Dr. Denis O'Brien has 4 office locations.
Dr. Denis O'Brien practices Orthopaedic Surgery and Surgery near Olney, MD.
Additional practice locations include: Silver Spring, MD and Ellicott City, MD.
See Olney Orthopedic Surgeons and Olney Surgeons.