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Jaimo Ahn, MD, PhD, FACS

Associate Professor of Orthopaedic Surgery at the Hospital of the University of Pennsylvania
Attending Orthopaedic Surgeon , Hospital of the University of Pennsylvania, Penn-Presbyterian Medical Center,Pennsylvania Hospital, Philadelphia, PA
Assistant Director, Orthopaedic Surgery Residency Program, University of Pennsylvania
Co-Director, Penn Orthopaedic Trauma and Fracture Reconstruction
Associate Director, Orthopaedic Surgery Residency Program , University Pennsylvania
Advisory Dean, University of Pennsylvania
Department: Orthopaedic Surgery

Contact information
Penn Presbyterian Medical Center
Orthopaedic Trauma and Fracture Service
3737 Market St, 6121
Philadelphia, PA 19104
Office: (215) 662-3340
Fax: (215) 349-5890
BS (Biological Sciences)
Stanford University, 1994.
PhD (Cell & Molecular Biology)
University of Pennsylvania School of Medicine, 1999.
MD (Medicine)
University of Pennsylvania School of Medicine, 2003.
Post-Graduate Training
Post-doctoral Fellow, Orthopaedic Surgery, University of Pennsylvania, 2000-2001.
Intern, General & Orthopaedic Surgery, University of Pennsylvania, 2003-2004.
Orthopaedic Surgery Residency , University of Pennsylvania Health System & Children's Hospital of Philadelphia, 2003-2008.
Clinician Scientist Development Program, AAOS-OREF-ORS, 2005-2005.
Fellow, Orthopaedic Trauma, Hospital for Special Surgery & Cornell University, 2008-2009.
Fellow, AO Trauma & Hip, Inselspital & University of Bern, Switzerland, 2009-2009.
Young Investigators Initiative, US Bone & Joint Initiative, 2011-2011.
Faculty Education Program, AO Foundation, 2012-2012.
Educator's Course, AAOS, 2013-2013.
USMLE Certification, 2001.
Advanced Trauma Life Support , 2003.
Advanced Cardiac Life Support, 2008.
American Board of Orthopaedic Surgery (Diplomate), 2011.
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Description of Research Expertise

I am an MD-PhD clinician-scientist with medical and scientific interest in the outcomes of orthopaedic trauma and fracture treatment and the molecular enhancement of bone formation and fracture healing. My investigative goals include the identification of interventions (biological, mechanical/surgical, decision-making) that improve patient care, to better understand them in the laboratory and to adapt them to the patient population that I treat. To those ends, I work with several interdisciplinary teams consisting of biologists, engineers, surgeons, veterinarians, clinical investigators to enhance our understanding and provision of orthopaedic care.

>> Gene regulation in bone healing - Using my background in molecular biology and gene regulation, I have delved into the investigation of a number of pathways and processes in bone healing and regulation that are consistent and synergistic with my orthopaedic trauma practice. I utilize primarily mouse models of traumatic fracture healing (with my collaborator, Kurt Hankenson) and have studied pathways related to thrombospondins, Wnt and Notch; and I have been especially interested in the geriatric condition (both fractures and bone loss). Select publications:
• Hebb JH, Ashley JW, McDaniel L, Lopas LA, Tobias J, Hankenson KD, Ahn J. Bone healing in an aged murine fracture model is characterized by sustained callus inflammation and decreased cell proliferation. J Orthop Res. Epub Jul 14, 2017.
• Ashley JW, Ahn J, Hankenson KD. Notch signaling promotes osteoclast maturation and resorptive activity. J Cell Biochem. 2015 Nov;116(11):2598-609.
• Lopas LA, Belkin NS, Mutyaba PL, Gray CF, Hankenson KD, Ahn J. Fractures in geriatric mice show decreased callus expansion and bone volume. Clin Orthop Relat Res. 2014 Nov;472(11):3523-32.
• Mutyaba PL, Belkin NS, Lopas L, Gray CF, Dopkin D, Hankenson KD, Ahn J. Notch signaling in mesenchymal stem cells harvested from geriatric mice. J Orthop Trauma. 2014;28 Suppl 1:S20-3.
• Dishowitz MI, Mutyaba PL, Takacs JD, Barr AM, Engiles JB, Ahn J, Hankenson KD. Systemic inhibition of canonical Notch signaling results in sustained callus inflammation and alters multiple phases of fracture healing. PLoS One. 2013 Jul 3;8(7):e68726.

>> Improving paradigms of medical decision-making - My investigations have led me to become involved in the systematic analysis of orthopaedic outcomes data and the systematic dissemination of education and information regarding evidence-based medicine. My collaborator, Joseph Bernstein, and I have taken this a step further and asked how to take medical decision-making into the future by not only refining what we know but exploring new methods to create improved paradigms to come to better clinical conclusions. Select publications:
• Bernstein J, LeBrun D, MacCourt D, Ahn J. Presumed consent: licenses and limits inferred from the case of geriatric hip fractures. BMC Med Ethics. 2017;18(1):17.
• Bernstein J, Kupperman E, Kandel LA, Ahn J. Shared Decision Making, Fast and Slow: Implications for Informed Consent, Resource Utilization, and Patient Satisfaction in Orthopaedic Surgery. J Am Acad Orthop Surg. 2016;24:495-502.
• Bernstein JR, Maliha G, Ahn J, Bernstein J. Levels of Influence: Habituation and the Prevalence of Declared Conflicts of Interest. J Bone Joint Surg Am. 2016 Nov 16;98(22):e99.
• Bernstein J, Morshed S, Helfet DL, Bhandari M, Ahn J. Applying evidence-based medicine principles to hip fracture management. Front Surg. 2014 Oct 20;1:40.
• Bernstein J, Long JS, Veillette C, Ahn J. Crowd intelligence for the classification of fractures and beyond. PLoS One. 2011;6(11):e27620.

>> Medical education (especially, the clinician-scientist) - Advances in biomedicine are driven by clinically minded scientists and scientifically minded clinicians. I have been studying, refining, improving, advocating for greater data-driven education and resource allocation for the training of medical scientists and clinician-scientists from the stages of undergraduate medical education and throughout graduate training. Select publications:
• Winterton M, Ahn J, Bernstein J. The prevalence and cost of medical student visiting rotations. BMC Med Educ. 2016 Nov 14;16(1):291.
• Schenker ML, Baldwin KD, Israelite CL, Levin LS, Mehta S, Ahn J. Selecting the Best and Brightest: A Structured Approach to Orthopedic Resident Selection. J Surg Educ. 2016 May 23.
• Daye D, Patel CB, Ahn J, Nguyen FT. Challenges and opportunities for reinvigorating the physician-scientist pipeline. J Clin Invest. 2015 Mar 2;125(3):883-7.
• Atesok KI, Hurwitz SR, Egol KA, Ahn J, Owens BD, Crosby LA, Pellegrini VD Jr. Perspective: Integrating research into surgical residency education: lessons learned from orthopaedic surgery. Acad Med. 2012 May;87(5):592-7.
• Baldwin K, Namdari S, Bowers A, Keenan MA, Levin LS, Ahn J. Factors affecting interest in orthopedics among female medical students: a prospective analysis. Orthopedics. 2011 Dec 6;34(12):e919-32.

>> The Practice of orthopaedic surgery. Select publications:
• Baron MD, DeFrancesco CJ, Liu TC, Leone FT, Ahn J. A Teachable Moment After Orthopaedic Fracture in the Smoking Patient: A Randomized, Controlled Trial. J Orthop Trauma. 2017;31(8):e252-e254.
• Bernstein J, Roberts FO, Wiesel BB, Ahn J. Preoperative Testing for Hip Fracture Patients Delays Surgery, Prolongs Hospital Stays, and Rarely Dictates Care. J Orthop Trauma. 2016 Feb;30(2):78-80.
• Sagi HC / Ahn J, Ciesla D, Collinge C, Molina C, Obremskey WT, Guillamondegui O, Tornetta P 3rd; Orthopaedic Trauma Association Evidence Based Quality Value and Safety Committee. Venous Thromboembolism Prophylaxis in Orthopaedic Trauma Patients: A Survey of OTA Member Practice Patterns and OTA Expert Panel Recommendations. J Orthop Trauma. 2015 Oct;29(10):e355-62.
• Scolaro JA, Schenker ML, Yannascoli S, Baldwin K, Mehta S, Ahn J. Cigarette smoking increases complications following fracture: a systematic review. J Bone Joint Surg Am. 2014 Apr 16;96(8):674-81.
• Schenker ML, Yannascoli S, Baldwin KD, Ahn J, Mehta S. Does timing to operative debridement affect infectious complications in open long-bone fractures? A systematic review. J Bone Joint Surg Am. 2012 Jun 20;94(12):1057-64.

I welcome discussion especially from students and trainees.

Jaimo Ahn, MD, PhD, FACS
Advisory Dean | Admissions & MSTP Steering Committees
Medical Student & Assoc. Residency Director, Orthopaedic Surgery
Co-Director, Orthopaedic Trauma & Fracture Reconstruction
Perelman School of Medicine, University of Pennsylvania

Selected Publications

Schwartz Andrew M, Schenker Mara L, Ahn Jaimo, Willett Nick J: Building better bone: The weaving of biologic and engineering strategies for managing bone loss. Journal of orthopaedic research : official publication of the Orthopaedic Research Society May 2017.

OʼToole Robert V, Joshi Manjari, Carlini Anthony R, Sikorski Robert A, Dagal Armagan, Murray Clinton K, Weaver Michael J, Paryavi Ebrahim, Stall Alec C, Scharfstein Daniel O, Agel Julie, Zadnik Mary, Bosse Michael J, Castillo Renan C: Supplemental Perioperative Oxygen to Reduce Surgical Site Infection After High-Energy Fracture Surgery (OXYGEN Study). Journal of orthopaedic trauma 31 Suppl 1: S25-S31, Apr 2017.

FAITH Investigators.: Fracture fixation in the operative management of hip fractures (FAITH): an international, multicentre, randomised controlled trial. Lancet (London, England) 389(10078): 1519-1527, Apr 2017.

Kaur G, Ahn J, Hankenson KD, Ashley JW. : Stimulation of Notch Signaling in Mouse Osteoclast Precursors. JoVE Feb 2017 Notes: In press.

Bernstein Joseph, LeBrun Drake, MacCourt Duncan, Ahn Jaimo: Presumed consent: licenses and limits inferred from the case of geriatric hip fractures. BMC medical ethics 18(1): 17, Feb 2017.

Silvestre Jason, Ahn Jaimo, Levin L Scott: National Institutes of Health Funding to Departments of Orthopaedic Surgery at U.S. Medical Schools. The Journal of bone and joint surgery. American volume 99(2): e5, Jan 2017.

Bernstein JR, Ahn J, Mahili G, Bernstein J: Levels of Influence: Habituation and The Prevalence of Declared Conflicts of Interest. Journal of Bone and Joint Surgery 98(22): e99, Nov 2016.

Winterton M, Ahn, Bernstein J: The prevalence and cost of medical student visiting rotations. BMC Medical Education 16(1): 291, Nov 2016.

Burgers P T P W, Hoogendoorn M, Van Woensel E A C, Poolman R W, Bhandari M, Patka P, Van Lieshout E M M: Total medical costs of treating femoral neck fracture patients with hemi- or total hip arthroplasty: a cost analysis of a multicenter prospective study. Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA 27(6): 1999-2008, Jun 2016.

Schenker M, Baldwin K, Israelite CL, Levin LS, Mehta S, Ahn J: Selecting the Best and Brightest: A Structured Approach to Orthopedic Resident Selection. Journal of Surgical Education 73(5): 879–885, May 2016.

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Last updated: 03/15/2019
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