Penn Medicine Provider
Orthopaedic Surgery
John Gabriel Horneff, III, MD, FAAOS
4.9
(1144)
Accepting new patients
Sees patients age 18 and up
Penn Orthopaedics Pennsylvania Hospital - Cathcart Building
View 2 additional locations
Schedule onlineCall 800-789-7366

About me

  • Director, Shoulder and Elbow Fellowship
  • Associate Professor of Clinical Orthopaedic Surgery

Dr. Gabe Horneff is a board certified orthopaedic surgeon specializing in the treatment of shoulder and elbow conditions. Originally from southern New Jersey, he completed medical school and residency at the University of Pennsylvania. He was then awarded a fellowship in Shoulder and Elbow Surgery at the Rothman Institute at Thomas Jefferson University.

Dr. Horneff has been the recipient of numerous awards including the Joseph P. Iannotti Award for Excellence in Shoulder Surgery as well as the Rockwood Clinical Grant in Shoulder Care. He performs a variety of surgical procedures on the shoulder and elbow including arthroscopic surgery, fracture care, and arthroplasty for arthritic conditions.

Dr. Horneff has published many original papers, abstracts, and book chapters in the field of orthopaedic surgery with a focus on shoulder and elbow care. He remains academically active with a dedication to ongoing research of the shoulder and elbow. He current serves on multiple committees as a fellow of the American Academy of Orthopedic Surgeons (FAAOS) and as a member of the American Shoulder and Elbow Society.

Education and training

  • Medical School: University of Pennsylvania School of Medicine
  • Residency: Hospital of the University of Pennsylvania
  • Fellowship: Thomas Jefferson University Hospital

What my patients think about me

Average Rating
4.9

1144 reviews

Comments are submitted by patients and reflect their views and opinions. The comments are not endorsed by and do not necessarily reflect the views of Penn Medicine.

June 2025
5.0
5.0
knowledgeable and professional
May 2025
5.0
5.0
good communication
May 2025
5.0
5.0
dr horneff, is thorough, explains well your results/situation, he is respectful, and let you ask questions, and well mannered!
May 2025
5.0
5.0
pleasant and professional

Insurance accepted

My Locations

Penn Orthopaedics Pennsylvania Hospital - Cathcart Building

Penn Medicine hospital privileges

  • Hospital of the University of Pennsylvania: Has privileges to treat patients in the hospital.
  • Pennsylvania Hospital: Has privileges to treat patients in the hospital.
  • Penn Presbyterian Medical Center: Has privileges to treat patients in the hospital.
Dr. Horneff is a Penn Medicine physician. In New Jersey, providers are affiliated with Penn Medicine through Clinical Health Care Associates of New Jersey or Princeton Healthcare Affiliated Physicians, PC.

Qualifications and experience

Treatments and Conditions

My research

Lawand JJ, Rizk AA, Sogbein OA, Granruth C, Ghali A, Hill BW, Khan AZ, Horneff JG, Abboud JA. Preoperative malnutrition is associated with increased risk of 90-day major medical complications and increased 2-year revision rates following total shoulder arthroplasty. , J Shoulder Elbow Surg.: 2025

Daher M, Parmar T, Boufadel P, Mares MY, Khalil W, Horneff JG, Abboud JA, Khan AZ. Patient-specific instrumentation in primary total shoulder arthroplasty: a meta-analysis of clinical outcomes. Clin Shoulder Elb. 2025 Apr 30. (Online ahead of print). , Clin Shoulder Elb.: 2025

Livesey M, Myerson CL, Horneff JG 3rd. Reverse shoulder arthroplasty in the revision setting. , JSES International: 2025

Fares MY, Parmar T, Boufadel P, Daher M, Berg J, Witt A, Hill BW, Horneff JG, Khan AZ, Abboud JA. An assessment of the performance of different chatbots on shoulder and elbow questions. , J Clin Med., 14(7): 2025,2289

Benjamin R Campbell, Corey J Schiffman, Raymond E Chen, Justin C Wong, John G Horneff, Mark D Lazarus Clinical and radiographic outcomes of shoulder hemiarthroplasty for patients with glenoid medialization , Journal of Shoulder and Elbow Surgery, 34(1): 2025,e15-e21

Mohammad Daher, Oscar Cobvarrubias, Peter Boufadel, Mohamad Y Fares, Daniel E Goltz, Adam Z Khan, John G Horneff, Joseph A Abboud Outpatient versus inpatient total shoulder arthroplasty: a meta-analysis of clinical outcomes and adverse events , International Orthopaedics, 49(1): 2025,151-165

Gutman MJ, Patel MS, Connelly JW, Paxton ES, Namdari S, Horneff JG. Early clinical outcomes of polyaxial locking cap plate fixation for fixation of displaced olecranon fractures. , Arch Bone Jt Surg., 13(1): 2025,23-29

John G Horneff, Joseph A Abboud, Antonia Chen, Asif Ilyas Reducing opioid use in orthopaedic surgery , AAOS Instructional Course Lectures, 74: 2025,313-322

Horneff JG 3rd, Abboud JA, Chen AF, Ilyas A. Chapter 25: Reducing Opioid Use in Orthopaedic Surgery , AAOS Instructional Course Lectures, Volume 74.: 2025

Rashad Madi, Ryan Lopez, Holt S Cutler, C Lucas Myerson, Alexander Lee, Cody Hansen, David L Glaser, G Russell Huffman, John D Kelly 4th, John G Horneff 3rd Primary open Latarjet procedure versus revision to open Latarjet procedure for anterior shoulder instability , Orthopedics, 47(6): 2024,343-348

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