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Effective 01/01/2019, TSAOG Orthopaedics is BACK IN NETWORK with Blue Cross and Blue Shield of Texas! 


Robert U. Hartzler, M.D., M.S.

Shoulder and Elbow; Sports Medicine; Joint Replacement


Dr. Hartzler is an orthopaedic surgeon with The San Antonio Orthopaedic Group. He is board certified by the American Board of Orthopaedic Surgery (ABOS) and fellowship trained in sports medicine and conditions of the shoulder and elbow. Dr. Hartzler treats all orthopedic conditions, with a focus on the shoulder and elbow, for patients aged 6 years and up.

Dr. Hartzler has a special interest in the complex arthroscopic repair of disorders and injuries of the shoulder and elbow as well as joint replacement for the shoulder and elbow. He has appointments available at our Stone Oak, Medical Center, and Central locations.

Dr. Robert Hartzler is an orthopaedic surgeon specializing in shoulder and elbow surgery and sports medicine. Although he treats many general orthopaedic conditions, he has a special interest in shoulder and elbow arthroscopy, reconstruction, and trauma surgery.

Dr. Hartzler was born in Austin and graduated from high school in Irving. After studying chemical engineering at The University of Texas at Austin, he taught junior high math and science in Austin. He was the highest ranking graduate from his medical school class at The University of Texas Southwestern Medical School and went on to complete his orthopaedic surgery residency at the Mayo Clinic.

Following his residency, Dr. Hartzler pursued his special interest in care of the shoulder and elbow, completing two separate fellowships (in shoulder and elbow reconstructive surgery and shoulder arthroscopy, respectively).

Dr. Hartzler remains active in the orthopaedic academic community. He has published scientific articles and book chapters on various topics related to shoulder and elbow surgery. He volunteers as a peer reviewer for The Journal of Shoulder and Elbow Surgery and Arthroscopy and has presented his scientific research at several academic meetings. Additionally, Dr. Hartzler has many active research and writing projects with his physician partners at TSAOG as well as UTHSCSA medical students.

Dr. Hartzler is married, and has three children.  He enjoys running, working out, and spending time with his family.

Dr. Hartzler was named to SA Scene’s list of SA Doctors: Best of 2017 and 2017 Rising Star Doctors.

View Dr. Hartzler’s CV

View Dr. Hartzler’s YouTube Playlist

Follow Dr. Hartzler on Twitter


Featured Video:

Arthroscopy and Sports Medicine
Shoulder arthroscopic treatment of rotator cuff tears

  • including arthroscopic repair of massive tears and revision repairs

Shoulder dislocations and chronic instability

  • including arthroscopic treatment of complex cases; treatment of bone loss with the Latarjet Procedure

Elbow arthroscopy
Problems with the thrower’s shoulder and elbow

Joint Replacement and Joint Preservation Surgery
Arthroscopic shoulder resurfacing for arthritis (joint preservation)
Reverse Shoulder Replacement
Total Shoulder Arthroplasty Replacement
Arthroscopic elbow surgery for arthritis (joint preservation)
Elbow replacement
Knee Replacement

  • Including partial knee replacement

Hip Replacement

Fracture and Trauma care
Upper extremity, specializing in clavicle, shoulder, arm, and elbow fractures
Lower extremity


Surgical Outcome Score (SOS) data was collected from May 2017 through January 2019:

  • The Visual Analog Pain Scale (VAS) records a patient’s self-reported pain level on a scale from 0-10, where 0 is no pain and 10 is the worst pain possible.
  • The ASES Shoulder Index Score records a patient’s self-reported outcome using a combination of pain level and shoulder function on a scale from 0-100, where 0 represents maximum pain and inability to perform 10 activities of daily living and 100 represents no pain and no difficulty performing 10 activities of daily living.

Scores are recorded prior to surgery and at designated intervals following surgery. Ideally, graphs using the Visual Analog Pain Scale should show a downward trend over time (as pain decreases) and graphs using the ASES Shoulder Index Score should show an upward trend over time (as shoulder function increases and pain decreases).


Total Shoulder Replacement – VAS:

Total Shoulder Replacement – ASES:

Reverse Total Shoulder Replacement – VAS:

Reverse Total Shoulder Replacement – ASES:

Proximal Humerus Fracture Repair – VAS:

Proximal Humerus Fracture Repair – ASES:

Rotator Cuff Repair – VAS:

Rotator Cuff Repair – ASES:

Clinical Coordinator
Deirdre R: 210.804.5630

Phone: 210.281.9595
Fax: 210.582.2670

Referrals and Authorizations
Phone: 210.804.5600
Fax: 210.804.5601

Billing Specialist
Phone: 210.396.5369
Fax: 210.804.6801


Joe Sigala, PA-C

Physician Assistant to Dr. Robert Hartzler

T: (210) 804-5630
F: (210) 804-5633

What is a P.A.?

Work History
Physician Assistant-Certified to Stephen Burkhart, M.D.
The San Antonio Orthopaedic Group, LLP
San Antonio, TX

Physician Assistant-Certified
New Braunfels Orthopaedic Surgery and Sports Medicine

The University of Texas Health Science Center San Antonio
Masters of Physician Assistant Studies
San Antonio, TX

The University of Texas at San Antonio
Masters of Science in Biology
San Antonio, TX

St. Mary’s University
Bachelors of Science in Biology
San Antonio, TX

Certification & Licensure
National Commission on Certification of Physician Assistants, 2013
Texas State Board of Physician Assistant Examiners, 2013
American Heart Association Basic Life Support Provider, 2013 to Present 

Professional Affiliations
American Academy of Physician Assistants
Texas Academy of Physician Assistants  

The National Honor Society for Physician Assistants (Pi Alpha) Graduate, 2013

South Texas PTSD Community Awareness and Response Education Seminar (C.A.R.E.S.)
The University of Texas Health Science Center San Antonio, 2013

Call (210) 804-5400
for Appointment
  • Medical Center
    Christus Santa Rosa NW, Tower I
    2829 Babcock Rd., #700
    San Antonio, TX 78229
    View Location
  • Quarry Area
    The Orthopaedic Institute
    400 Concord Plaza Dr.
    San Antonio, TX 78216
    View Location
  • Stone Oak
    Stoneterra Medical Building
    150 E. Sonterra Blvd, #300
    San Antonio, TX 78258
    View Location

Clinical Coordinator
Deirdre R: 210.804.5630

Phone: 210.281.9595
Fax: 210.582.2670

Referrals and Authorizations
Phone: 210.804.5600
Fax: 210.804.5601

Billing Specialist
Phone: 210.396.5369
Fax: 210.804.6801