Dr. Gregory S. DiFelice is a fellowship-trained orthopedic surgeon specializing in Sports Traumatology and Joint Reconstruction Surgery at Hospital for Special Surgery and New York-Presbyterian Hospital. He also holds an academic appointment at the Weill Medical College of Cornell University as an Associate Attending Orthopedic Surgeon. His main surgical focus is on the treatment of the knee, shoulder, and hip. Using both non-surgical and surgical methods, he strives to utilize the latest technologies to improve patient outcomes, while preserving their native tissues. He refers to his customized approach as Preservation First, and this guides his practice. His philosophy, developed over 20+ years in practice, is to use surgery as a last resort, and if surgery is absolutely necessary, to perform the most conservative surgery that will give the best, most long-lasting results for the patient. This delicate balancing of the risks and benefits of surgery for each individual is, in essence, the art of surgery.
Dr. DiFelice is a surgical innovator and has developed several cutting-edge surgical techniques that allow him to save a patients’ torn ligaments, rather than replacing them, which is the current standard of care. His approach is called ligament preservation and includes conservative, minimally invasive techniques such as primary repair and primary repair with augmentation. By saving the patients’ native ligament tissues, he greatly reduces surgical injury to the patient, and thus diminishes the recovery time and restores more of the natural function of the knee. Currently, for 50% to 75% of his ACL injured patients, he is able to save most, if not all, of the patients’ native tissue, thereby diminishing the need for grafts. He uses ACL reconstruction – the replacing of the torn ligament with a graft, which is considered the standard of care throughout the world – only as a last resort when there is little or no native tissue available to save. As the surgical innovator of his modern-day preservation approach, he has published and lectured extensively, both domestically and internationally, on this and other topics.
Not all ligaments, nor all joints for that matter, can be saved, however. Dr. DiFelices’ Preservation First approach to surgery is also evident in his approach to arthritic joints. Rather than the standard approach of the majority of surgeons, in which most people with arthritis of the knee or hip get a total joint replacement surgery, his approach is more nuanced and is customized for each patient, based on their health, activity level and particular pattern of arthritis. He is an expert in both realignment osteotomy and robotic, unicompartmental arthroplasty – two techniques that allow the patient to avoid the larger, more morbid total joint arthroplasty when in their best interests. In addition, he is also an expert in both total hip and total knee arthroplasty, having performed thousands of these procedures over his 20+-year career, which allows him to provide patients with the treatment option that is best for them.
Associate Attending Orthopedic Surgeon, Hospital for Special Surgery
Associate Professor, Clinical Orthopedic Surgery, Weill Cornell Medical College
Associate Attending Orthopedic Surgeon, NewYork-Presbyterian Hospital
ACL and Ligament Preservation
Multi-ligament Knee Injury
Arthroscopic Knee surgery
Arthroplasty of the Knee and Hip
Knee ligament reconstruction & repair
Meniscal & cartilage surgery
Rotator cuff repair
Joint replacement of the knee and hip
The Associate of Bone and Joint Surgeons Clinical Orthopedics and Related Research Multimedia Award 2011
Patient Choice Award - Vitals.com 2008, 2009, 2010,2011, 2013, 2014, 2016, 2017, 2018
Teacher of the Year Award - Montefiore Orthopaedic Residency Program 2002 & 2005
American Academy of Orthopaedic Surgeons
American Orthopaedic Society for Sports Medicine
American Association of Hip and Knee Surgeons
New York State Society of Orthopaedic Surgeons
Medical Society of the State of New York
Alpha Omega Alpha Medical Honor Society- NJ Beta Chapter
One of the goals of HSS is to advance the science of orthopedic surgery, rheumatology, and related disciplines for the benefit of patients. Physicians at HSS may collaborate with outside companies for education, research and medical advances. HSS supports this collaboration in order to foster medical breakthroughs; however HSS also believes that these collaborations must be disclosed.
As part of the disclosure process, this website lists physician collaborations with outside companies. The disclosures are provided by information provided by the physician and other sources and are updated regularly. Further information may be available on individual company websites.
Below are the healthcare industry relationships reported by Dr. DiFelice as of September 17, 2019.
By disclosing the collaborations of HSS physicians with industry on this website, HSS and its physicians make this information available to their patients and the public, thus creating a transparent environment for those who are interested in this information. Further, the HSS Conflicts of Interest Policy does not permit physicians to collect royalties on products developed by him/her that are used on patients at HSS.
Patients should feel free to ask their HSS physicians questions about these relationships.
MD, UMDNJ- New Jersey Medical School, Newark, NJ/USA, 1994
Orthopedic Surgery, Hospital for Special Surgery, New York, NY/USA, 1999
Board Certified, ABOS, July 2003
New York, New Jersey
van der List JP, DiFelice GS. The Role of Ligament Repair in ACL Surgery. In: Ligamentous Injuries of the Knee, 2016, pp. 199-220.
DiFelice GS, van der List JP. Arthroscopic suture anchor primary ACL repair. In: Insall and Scott Surgery of the Knee (6th edition).
van der List JP, DiFelice GS. Primary Repair in the Pediatric Patient. In: The Pediatric ACL, 2017, Springer Publications. pp. 227-239.
Jonkergouw, Anne & Van der List, Jelle & Difelice, Gregory. (2019). Arthroscopic Primary Repair in the Multiple-Ligament Injured Knee. 10.1007/978-3-030-05396-3_14.
Vermeijden HD, Van der List JP, DiFelice GS. Cruciate ligament repair. The Complex Knee Management Guide: Restoring the Anatomy to Achieve Best Outcomes, in press.
DiFelice GS, Villegas C, Taylor SA. Anterior Cruciate Ligament Preservation: Early Results of a Novel Arthroscopic Technique for Suture Anchor Primary Anterior Cruciate Ligament Repair. Arthroscopy. 2015;31(11):2162-2171.
Taylor SA, Khair MM, Roberts TR, DiFelice, GS. Primary Repair of the Anterior Cruciate Ligament: A Systematic Review. Arthroscopy. 2015;31(11):2233-2247.
DiFelice GS, van der List JP. Arthroscopic primary repair of posterior cruciate ligament injuries. Oper Tech Sports Med. 2015;23(4):307-314.
van der List JP, DiFelice GS. Primary repair of the anterior cruciate ligament: A paradigm shift. Surgeon 2017;15(3):161-168.
DiFelice GS, van der List JP. Arthroscopic primary repair of proximal anterior cruciate ligament tears. Arthrosc Tech. 2016;5(5):e1057-e1061.
van der List JP, DiFelice GS. Gap formation following primary anterior cruciate ligament repair: a biomechanical study. Knee. 2017;24(2):243-249.
van der List JP, DiFelice GS. Preservation of the anterior cruciate ligament: A treatment algorithm based on tear location and tissue quality. Am J Orthop. 2016;45(7):E393-E405.
van der List JP, DiFelice GS. Preservation of the anterior cruciate ligament: Surgical techniques. Am J Orthop. 2016;45(7):E406-E414.
van der List JP, DiFelice GS. Successful arthroscopic primary repair of a chronic anterior cruciate ligament tear 11 years following injury. HSS J. 2017;13(1):90-95.
DiFelice GS, van der List JP. Regarding "Acute Proximal Anterior Cruciate Ligament Tears: Outcomes After Arthroscopic Suture Anchor Repair Versus Anatomic Single-Bundle Reconstruction". Arthroscopy. 2017;33(4):693-694.
van der List JP, DiFelice GS. Range of motion and complications following primary repair versus reconstruction of the anterior cruciate ligament. Knee. 2017;24(4):798-807.
van der List JP, DiFelice GS. The location of the anterior cruciate ligament tears: a prevalence study using magnetic resonance imaging. Orthop J Sports Med. 2017; 5(6):2325967117709966.
van der List JP, DiFelice GS. Primary repair of the medial collateral ligament with internal bracing. Arthrosc Tech. 2017;3(4);e933-e937.
van der List JP, DiFelice GS. The location of anterior cruciate ligament tears in Paediatric and Adolescent Patients: A magnetic resonance imaging study. J Ped Orthop. 2017;5(6):2325967117709966.
van der List JP, DiFelice GS. Role of tear location on outcomes of open primary repair of the anterior cruciate ligament: a systematic review of historical studies. Knee. 2017;24(5):898-908
van der List JP, DiFelice GS. Preoperative magnetic resonance imaging predicts eligibility for arthroscopic primary anterior cruciate ligament repair. Knee Surg Sports Traumatol Arthrosc. 2017;26(2):660-671
van der List JP, DiFelice GS. Arthroscopic primary repair of the anterior cruciate ligament with suture augmentation. Arthrosc Tech. 2017;6(5):e1459-e1534
van der List JP, DiFelice GS. Arthroscopic primary repair of the posterior cruciate ligament with suture augmentation. Arthrosc Tech. 20176(5):e1685-e1690
Daniels SP, van der List, JP, Kazam, JJ, DiFelice, GS. Arthroscopic primary repair of the anterior cruciate ligament: what the radiologist needs to know. Skeletal Radiol. 2018;47(5):619-629.
DiFelice GS, van der List JP. Clinical outcomes of arthroscopic primary repair of proximal anterior cruciate ligament tears are maintained at mid-term follow-up. Arthroscopy. 2018;34(4):1085-1093.
van der List JP, DiFelice GS. Reply to the letter to the editor regarding our article ‘Preoperative magnetic resonance imaging predicts eligibility for arthroscopic primary anterior cruciate ligament repair.’ Knee Surg Sports Traumatol Arthrosc. 2018;26(2):672-673.
Jonkergouw A, van der List JP, DiFelice GS. Multiligament repair with suture augmentation is a knee dislocation with medial-sided injury. Arthrosc Tech. 2018;7(8):e839-e843.
Jonkergouw A, van der List JP, DiFelice GS. Arthroscopic primary repair of proximal anterior cruciate ligament tears: outcomes of the first 56 consecutive patients and the role of additional internal bracing. Knee Surg Sports Traumatol Arthrosc. 2019;27(1):21-28.
Ahmed SS, DiFelice GS, van der List JP, Ateschrang A, Hirschmann MT. Primary repair of the anterior cruciate ligament: real innovation or reinvention of the wheel? Knee Surg Sports Traumatol Arthrosc. 2019:27(1);1-2.
van der List JP, Jonkergouw A, van Noort A, Kerkhoffs GMMJ, DiFelice GS, Identifying candidates for arthroscopic primary repair of the anterior cruciate ligament: a case-control study. Knee. 2019. In press.
van der List JP, Mintz DN, DiFelice GS. Postoperative magnetic resonance imaging following arthroscopic primary anterior cruciate ligament repair. Advances in Orthopedics. 2019;1-9.
van der List JP, Vermeijden HD, DiFelice, GS. Anterior cruciate ligament reconstruction following failed primary repair: surgical technique and a report of three cases. Minerva Ortoped e Trauma. 2019;70(2):70-7
HD Vermeijden, JP van der List, GS DiFelice. Arthroscopic Posterior Cruciate Ligament Primary Repair. Sports Medicine and Arthroscopy Review 2020; 28: 23-29
Van Der List JP, Mintz DN, Difelice GS. The Locations of Anterior Cruciate Ligament Tears in Pediatric and Adolescent Patients: A Magnetic Resonance Study. J Pediatr Orthop 2019;39:441–448.
Vermeijden HD, van der List JP, O’Brien RJ, DiFelice GS. Patients Forget About Their Operated Knee More Following Arthroscopic Primary Repair of the Anterior Cruciate Ligament Than Following Reconstruction. Arthroscopy 2020;36:797–804
van der List JP, Vermeijden HD, Sierevelt IN, et al. Arthroscopic primary repair of proximal anterior cruciate ligament tears seems safe but higher level of evidence is needed: a systematic review and meta-analysis of recent literature. Knee Surg Sport Traumatol Arthrosc. 2020
Vermeijden HD, Yang XA, van der List JP, DiFelice GS. Large variation in indications, preferred surgical technique and rehabilitation protocol for primary anterior cruciate ligament repair: a survey among ESSKA members. Knee Surg Sports Traumatol Arthrosc. 2020
Vermeijden HD, Jonkergouw A, Van der List JP, DiFelice GS. The Multiple Ligament Injured Knee: When is Primary Repair an Option? Knee, 2020;27(1):173-182.
Vermeijden HD, Van der List JP, DiFelice GS. Arthroscopic Primary Repair of the Anterior Cruciate Ligament with Single-Bundle Graft Augmentation. Arth Tech, 2020;9(3):e367-e373.
Vermeijden HD, O’Brien R, Van der List JP, DiFelice GS. Return to Sports Following Arthroscopic Primary Repair of the Anterior Cruciate Ligament in the Adult Population. Knee 2020;S0968-0160(20)30076-4.
Vermeijden HD, Van der List JP, DiFelice GS. Primary Repair of the Lateral Collateral Ligament using Additional Suture Augmentation. Arth Tech, in press.
Bachmaier S, DiFelice GS, Sonnery-Cottet B, et al . Treatment of Acute Proximal Anterior Cruciate Ligament Tears—Part 1: Gap Formation and Stabilization Potential of Repair Techniques. Orthop J Sport Med 2020;8:
Bachmaier S, DiFelice GS, Sonnery-Cottet B, et al. Treatment of Acute Proximal Anterior Cruciate Ligament Tears-Part 2: The Role of Internal Bracing on Gap Formation and Stabilization of Repair Techniques. Orthop J Sport Med 2020;8:2325967119897423.
Vermeijden, H.D., Yang, X.A., van der List, J.P. et al. Trauma and femoral tunnel position are the most common failure modes of anterior cruciate ligament reconstruction: a systematic review. Knee Surg Sports Traumatol Arthrosc (2020). https://doi.org/10.1007/s00167-020-06160-9
Vermeijden HD, Jonkergouw A, Van der List JP, DiFelice GS. The role of age on the failure rates and patient-reported outcomes following arthroscopic primary repair of proximal anterior cruciate ligament tears Arthrosopy, in submission.
Lin KM, Vermeijden HD, Klinger CE, Lazaro LE, Dyke JP, Rodeo SA, DiFelice GS. Differential Regional Perfusion of the Human Anterior Cruciate Ligament: A Quantitative MRI Assessment. Am J Sports Med., in submission.
van der List JP, DiFelice GS. A Closer Look at Primary Arthroscopic ACL Repair. Orthopedics Today. April 2016.
DiFelice GS, Sonnery-Cottet B, Douoguih WA, van der List JP. Should We Rethink How to Define Success After ACL Surgery? Letter to the Editor. Am. J. Sports Med. 2019;47:NP58–NP59
For more publications, please see the PubMed listing.
Arthroscopic Primary Repair of Proximal Anterior Cruciate Ligament Tears: With or Without Additional Suture Augmentation? AOSSM Annual Meeting. San Diego, CA. July 5-7, 2018.
Arthroscopic primary repair of proximal anterior cruciate ligament tears:With or without internal brace? Poster presentation at the 18th Biennial Meeting of the European Society for Sports Traumatology, Knee Surgery and Arthroscopy, Glasgow, Scotland. May 9 – 12, 2018.
Good outcomes of arthroscopic primary repair of proximal anterior cruciate ligament tears are maintained at mid-term follow-up. Poster presentation at the 18th Biennial Meeting of the European Society for Sports Traumatology, Knee Surgery and Arthroscopy, Glasgow, Scotland. May 9 – 12, 2018.
The location of anterior cruciate ligament tears: a prevalence study using magnetic resonance imaging. Podium presentation at the 85th Annual Meeting of American Academy of Orthopaedic Surgeons, New Orleans, LA, USA. March 6 – 10, 2018.
DiFelice, GS. We can get ACL to heal-Techniques & results. Warwick Orthopaedics Sports Knee Conference. Staffordshire, UK. November 20-21, 2017.
Primary ACL Repair: Why We Don’t, Why We Should, and How I do It? 4th Joint Preservation Congress. Warsaw, Poland. September 14-16, 2017.
Case Presentation: Multi-Ligament Knee Reconstruction,Technique and Fixation DeviceChoices, Surgical & Patient Selection Tips for Successful Surgical Outcomes. Grand Rounds: Michigan State University. Grand Rapids, MI. May 16-17, 2017.
Emerging Technique: ACL Repair. 2017 Kaiser Permanente Dale Daniel Orthopaedic Symposium. Huntington Beach, CA. February 11, 2017.
The Incidence of Proximal Avulsion Anterior Cruciate Ligament Tears: A Magnetic Resonance Imaging Evaluation. E-poster presentation at 11th Biennial ISAKOS Congress. June 4 – 8, 2017, Shanghai, China.
Is There a Role for Primary Repair of ACL Injuries? National Capital Knee Symposium, University of Ottawa. Ottawa, Canada. September 15-16, 2016.
ACL Repair- is there a role? Fortius International Sports Injury Conference. London, UK. October 12-13, 2015.
Surgical Spotlight: Overview of Anterolateral Ligament. AOSSM Annual Meeting 2015. Orlando, FL. July 9-12, 2015.
Suture Anchor Versus Drill Tunnel Primary ACL Repair: An In Vitro Comparison of Gap Formation, ISAKOS Congress, June 7-11, 2015.
ACL Preservation: Early Results of A Novel Arthroscopic Technique of Suture Anchor Primary ACL Repair, AANA Annual Meeting, April 23-25, 2015.
Knee Injuries in Athletes: Getting Patients Back in the Game. Rosemont, IL. April 8-10, 2010. Invited Instructor.
Dr. DiFelice has a special interest in Ligament Preservation surgery. This includes his pioneering work on Primary ACL and PCL repairs, and Primary collateral repairs. In addition, this includes remnant preserving procedures for the knee ligaments. He has written and published extensively on these topics, and lectures both nationally and internationally on a regular basis to share his research with the orthopaedic and healthcare community.
ACL injuries have become commonplace, along with its traditional treatment of reconstruction. According to Dr. Gregory DiFelice, orthopedic sports trauma surgeon at HSS, one size does not fit all for ACL tears. He has developed an innovative approach to repair the native ACL in tears where the ligament is largely intact, but has been torn from its bony attachment. His technique saves the patient's native anatomy which results in better outcomes. Watch exclusive footage of his patients who have undergone this technique, all of which are included in the new results that Dr. DiFelice just published. To view the study, please visit: http://www.sciencedirect.com/science/article/pii/S0749806315006647.