Volume 30, June 2020

Letter from the Editors
George Fryhofer, MD, MTR and Kelsey Bonilla, MD

Letter from the Chair
L. Scott Levin, MD, FACS

Letter from the Program Director
Daniel Farber, MD

Dedication & In Memoriam: Dr. William George DeLong, Jr., MD
Christopher T. Born, MD, FACS, FAAOS

In Memoriam: Dr. Carl T. Brighton, MD, PhD
Marvin E. Steinberg, MD

In Memoriam: Dr. Denis Drummond, MD
John M. Flynn, MD

Editorials & Perspectives

Orthopaedic Student Interest Group and Departmental Collaboration
Joshua T. Bram, BS, Alejandro Cazzulino, BS, and Jaimo Ahn, MD, PhD

Perry Initiative: Increasing Diversity in Orthopaedic Medicine and Research
Jaclyn A. Carlson, MS, Ashley K. Fung, MS, Hannah M. Zlotnick, BS

Faculty Updates

Reflections on a Year as President of AAOS
Kristy Weber, MD

Celebrating the 40th Anniversary of the McKay Research Laboratory
George Fryhofer, MD, MTR and Robert Mauck, PhD

PCMD Symposium 2019
Kelsey Bonilla, MD

Penn Orthopaedics Research Day 2019
Kelsey Bonilla, MD

Department Updates

Orthopaedic Trauma Division Update
Samir Mehta, MD

Spine Division Update
Harvey Smith, MD

Sports Division Update
Brian Sennett, MD

Hand Division Update
David Bozentka, MD

Shoulder and Elbow Division Update
David Glaser, MD

Adult Reconstruction Division Update
Charles Nelson, MD

Foot and Ankle Division Update
Keith Wapner, MD

Orthopaedic Oncology Division Update
Kristy Weber, MD

Neuro-Orthopaedic Division Update
Keith Baldwin, MD, MPH, MSPT and David Spiegel, MD

Orthoplastics Limb Salvage Division Update
Meghan Wilson, RN, Stephen Kovach III, MD and L. Scott Levin, MD, FACS

Children’s Hospital of Philadelphia Update
Divya Talwar, PhD, MPH and John Flynn, MD

Resident and Fellow Updates

Chief’s Corner: Academic Chief Update
Daniel Gittings, MD, Mark Hasenauer, MD and Matthew Sloan, MD, MS

2019 Intern Bootcamp
Stephen Barchick, MD

Visiting Professor Series 2019-2020
George Fryhofer, MD, MTR

Class of 2010 Alumni Residents—Where Are They Now?
Kelsey Bonilla, MD

Residents and Fellows

Current Residents

Current Fellows

Health System Update

Corporal Michael J. Crescenz VA Medical Center
Richard E. Grant, MD

Pennsylvania Hospital
Neil Sheth, MD

Penn Center for Musculoskeletal Disorders
Louis J. Soslowsky, PhD

McKay Orthopaedic Research Laboratory
Robert L. Mauck, PhD

VAMC Translational Musculoskeletal Research Center
George R. Dodge, PhD

Biedermann Lab for Orthopaedic Research
Elaine Schmidt, MS, Kayley Dear, MSE, Danielle Cristino, PhD and Michael Hast, PhD

Human Motion Lab
Josh Baxter, PhD

Clinical Research Section
Annamarie D. Horan, MPA, PhD

Human Tissue Lab
Lorianne Kish-Burdsall

Poised for Growth and Expansion
Neil Ravitz, MBA

Continued Evolution of the MSKR Service Line
Sean Looby, MHA

Orthopaedic Advanced Practice Providers
Christine McAndrew, PA-C

Clinical Research


Trauma Tips & Tricks: Nail Plate Combination Fixation for Distal Femur Fractures
Kendall M. Masada, MD, Gregory T. Minutillo, MD, MPH and Derek J. Donegan, MD, MBA

Improving the Neer and AO Classifications of Greater Tuberosity Fractures: A Computational Framework
Michael W. Hast, PhD, Kayley Dear, BS, Josh Baxter, PhD and Surena Namdari, MD

Low Risk, High Impact: 3-D Printed Fracture Models for Resident Education
Danielle M. Cristino, PhD, Kayley A. Dear, BS, Elaine C. Schmidt MS, Michael W. Hast, PhD and Samir Mehta, MD

Nitinol Staple Fixation of Clavicle Fractures Results in a More Flexible Construct than Plating
Elaine C. Schmidt, MS, Chelsea Hendow, MD, Liane Miller, MD, Kayley Dear, BS, Samir Mehta, MD and Michael W. Hast, PhD

Topical Administration of Raloxifene Does Not Significantly Improve Bone Toughness or Screw Pull-out Strength
Michael R. Eby, MD, Danielle M. Christino, PhD, Matthew Counihan, MD, Kendall M. Masada, MD, Michael W. Hast, PhD and Jaimo Ahn, MD, PhD


Spine Tips & Tricks: Performing a Pedicle Subtraction Osteotomy (PSO)
Sachin Gupta, MD

Engineered Total Disc Replacements in a Large Animal Model Recapitulate Native Disc Structure and Function
Sarah E. Gullbrand, PhD, Beth G. Ashinsky, Dong Hwa Kim, PhD, Lachlan J. Smith, PhD, Dawn M. Elliott, PhD, Thomas P. Schaer, VMD, Robert L. Mauck, PhD and Harvey E. Smith, MD

Inflammatory Cytokine and Catabolic Enzyme Expression in a Goat Model of Intervertebral Disc Degeneration
Chenghao Zhang, PhD, Thomas P. Schaer, VMD, Sarah E. Gullbrand, PhD, Zhirui Jiang, PhD, Yian Khai Lau, BS, Dawn M. Elliott, PhD, George R. Dodge, PhD, Robert L. Mauck, PhD, Neil R. Malhotra, MD and Lachlan J. Smith, PhD


Sports Tips & Tricks: Distal Triceps Tendon Knotless Anatomic Footprint Repair
Eric M. Pridgen, MD, PhD, Daniel Gittings, MD and John D. Kelly IV, MD

State of the Field: The Utility of Ultrasound in the Diagnosis of Rotator Cuff Tears
Alexander Lee, BS, Ali S. Farooqi, BA, Robert L. Parisien, MD, Viviane Khoury, MD and John D. Kelly IV, MD

Bankart Repair versus Bankart Repair with Remplissage: Meta-analysis and Comparison of the Shoulder Re-Dislocation Rate
Gabrielle Leavitt, John D. Kelly IV, MD and Leslie Barnes, MD


Hand Tips & Tricks: Tendon Transfers for Pin Palsy—Principles and Technique
C. Lucas Myerson, MD, Martin Griffis, MD, Ketan Sharma, MD and Benjamin Gray, MD

Engineered Anatomic Implants Restore Geometry and Load Transfer in the Porcine Accessory Carpal Joint
Brendan D. Stoeckl, MSE, George W. Fryhofer, MD, MTR, Megan J. Farrell, PhD, Hannah M. Zlotnick, BS, Michael W. Hast, PhD, Thomas P. Schaer, VMD, David R. Steinberg, MD and Robert L. Mauck, PhD


Pediatrics Tips & Tricks: Pros and Cons of Waterproof Cast Liners in Pediatric Injuries
Brandon Haghverdian, MD

Pediatric Ramp Lesions: Incidence, MRI Sensitivity, and Associated Risk Factors
Joshua T. Bram, BS, Jie C. Nguyen MD, MS, Margaret L. Wright, MD, Tomasina M. Leska, BS, Julien T. Aoyama, BA and Theodore J. Ganley, MD

Pediatric Jones Fractures
Nicolas Pascual-Leone, BA, Nishank Mehta, BA, Joshua Bram, BS and Theodore Ganley, MD

Shoulder and Elbow

Shoulder Tips & Tricks: The Essentials of Physical Examination
Lauren M. Boden, MD, Stephanie A. Boden, MD and Allison L. Boden, MD

Long-Term Nicotine Exposure Alters Rat Supraspinatus Tendon and Bone Properties
Julianne Huegel, PhD, Courtney A. Nuss, Peter Chan, Adnan N. Cheema, MD, Andrew F. Kuntz, MD and Louis J. Soslowsky, PhD

Mechanisms of Action of Pulsed Electromagnetic Field Therapy on a Rat Model of Rotator Cuff Injury and Repair
Julianne Huegel, PhD, Stephanie N. Weiss, BS, Courtney A. Nuss, Harina Raja, MS, E.I. Waldorff, N. Zhang, J.T. Ryaby, Louis J. Soslowsky, PhD and Andrew F. Kuntz, MD


Arthroplasty Tips & Tricks: Manual Fixed-Bearing Medial Unicompartmental Arthroplasty
Yehuda E. Kerbel, MD, Rahul Singh, MBBS, Pedro N. Giglio, MD and Neil P. Sheth, MD

Comparison of Perioperative Adverse Outcomes Following Total Hip Arthroplasty In Patients with Diabetes: Insulin Dependence Makes a Difference
Matthew L. Webb, MD, Marissa A. Justen, BS, Andrew Konopitski, MD, Yehuda E. Kerbel, MD, Christopher M. Scanlon, MD, Charles L. Nelson, MD and Jonathan N. Grauer, MD

Ceramic-on-Ceramic Hip Arthroplasty in Young Patients: 12-year Median Follow-Up of Patients Aged 55 Years or Younger
Matthew L. Webb, MD, Perry J. Evangelista, MD, Andrew Konopitski, MD, Yehuda E. Kerbel, MD, Christopher M. Scanlon, MD and Charles L. Nelson, MD

Foot and Ankle

Case Report: Late Presentation of a Retained Stingray Spine in the Plantar Medial Hindfoot
David P. Falk, MD, Sreenivasulu Metikala, MD, Viviana Serra Lopez, MD, MS, Matthew Stein, MD, Karim Mahmoud, MD and Wen Chao, MD

Limited Scar Resection for Chronic Achilles Repair: Use of a Rat Model
Matthew Counihan, MD, Courtney Nuss, AS, Joseph Newton, BS, Louis Soslowsky, PhD and Daniel Farber, MD

Liquid Poly-N-Acetyl Glucosamine (sNAG) Improves Achilles Tendon Healing in a Rat Model
Courtney Nuss, AS, Julianne Huegel, PhD, Sergio Finkielsztein, BS and Louis Soslowsky, PhD

Microdialysis as a Longitudinal, In Vivo Assessment of Achilles Tendon Healing in a Rat Model
Joseph B. Newton, BS, Snehal S. Shetye, PhD, Courtney A. Nuss, AS, Matthew M. Counihan, MD, Daniel C. Farber, MD and Louis J. Soslowsky, PhD

The Role of Weight-Bearing Computed Tomography Scan in Hallux Valgus
Karim Mahmoud, MD, Sreenivasulu Metikala, MD, Samir D. Mehta, MD, George W. Fryhofer, MD, MTR and Daniel C. Farber, MD

Ultrasound Echogenicity is Associated with Fatigue Damage and Failure of Achilles Tendon in a Cadaveric Loading Model
Elaine C. Schmidt, MS, Todd J. Hullfish, BS, Kathryn O’Connor, MD, Michael W. Hast, PhD and Josh R. Baxter, PhD


Reflection: A Light in the Darkness
Andrew Summers, MD


Orthoplastics Tips & Tricks: The Posterior Interosseous Artery Reverse Flap for Coverage of Distal Upper Extremity Defects
Agnes Z. Dardas, MD, MSc and L. Scott Levin, MD, FACS, FAOA

Basic Science

Bone & Development

Single Cell Transcriptome Analysis of Aging Effect on Bone Marrow Mesenchymal Progenitors
Lutian Yao, MD, Leilei Zhong, PhD, Robert J. Tower, PhD, Yulong Wei, MD, Zhen Miao, PhD, Jihwan Park, PhD, Rojeshi Shrestha, Luqiang Wang, MD, PhD, Yejia Zhang, MD, PhD, Katalin Susztak, MD, PhD, Mingyao Li, PhD, Jaimo Ahn, MD, PhD and Ling Qin, PhD

Identification of a Novel Adipose Lineage Cell Population that Regulates Bone Marrow Environment
Leilei Zhong, PhD. Lutian Yao, MD, Robert J. Tower, PhD, Yulong Wei, MD, Luqiang Wang, MD, PhD, Yulong Wei, MD, Yejia Zhang, MD, PhD, Yanqing Gong, MS, PhD, Fanxin Long, PhD, Patrick Seale, PhD, Chider Chen, PhD, Jaimo Ahn, MD, PhD and Ling Qin, PhD

Biophysical Cues Regulate Nanoscale Chromatin Organization in Mesenchymal Stem Cells
Su-Jin Heo, PhD, Shreyasi Thakur, PhD, Claudia Loebel, MD, PhD, Peter Relich, PhD, Boao Xia, Jason Burdick, PhD, Melike Lakadamyali, PhD and Robert Mauck, PhD

Abnormal Vascularity and Extracellular Matrix Remodeling are Associated with Impaired Secondary Ossification in Mucopolysaccharidosis VII
Zhirui Jiang, PhD, Casey P. Johnson, PhD, Olli Nykänen, PhD, Mikko Nissi, PhD, Yian Khai Lau, Meilun Wu, Kai D. Ludwig, PhD, Jutta Ellerman, MD, Margret L. Casal, VM, MS, PhD and Lachlan J. Smith, PhD

Cellular Pathogenesis in Mucopolysaccharidosis Dogs at the Onset of Postnatal Growth
Zhirui Jiang, PhD, Yian Khai Lau, Margret L. Casal, PhD and Lachlan J. Smith, PhD

An Adaptable CT-Derived 3D-Printed Alignment Fixture Minimizes Errors in Whole-Bone Biomechanical Testing
Jordan V. Inacio, Danielle M. Cristino, PhD, Michael W. Hast, PhD and Hannah L. Dailey, PhD

Cartilage, Meniscus & Muscle

Dynamic Changes in the Porcine Meniscus and Articular Cartilage After Meniscal Injury
Sonia Bansal, BA, Liane M. Miller, MD, Jay M. Patel, PhD, Kamiel S. Saleh, BA, Brendan D. Stoeckl, MSE, Dawn M. Elliott, PhD, Michael W. Hast, PhD, Miltiadis H. Zgonis, MD, and Robert L. Mauck, PhD

Fabrication of Integrated Multi-Phasic MSC-Laden Composite Scaffolds for Osteochondral Repair
George W. Fryhofer, MD, MTR, Hannah M. Zlotnick, BS, Brendan D. Stoeckl, MSE, Megan J. Farrell, PhD, David R. Steinberg, MD and Robert L. Mauck, PhD

Cellular Dynamics And Zonal Specialization of the Murine Meniscus ECM During Postnatal Growth
Tonia K. Tsinman, BS, Xi Jiang, MS, MD, Lin Han, PhD, Eiki Koyama, PhD, DDS, Robert L. Mauck, PhD and Nathaniel A. Dyment, PhD

Identification of Gli1 as a Progenitor Cell Marker for Meniscus Injury Repair
Yulong Wei, MD, Hao Sun, MD, Lutian Yao, MD, Leilei Zhong, PhD, Wei Yu, Su Chin Heo, PhD, Lin Han, PhD, Fanxin Long, PhD, Robert L. Mauck, PhD, Jaimo Ahn, MD, PhD and Ling Qin, PhD

Gli1 Labels a Subpopulation of Fap Cells that Respond to Muscle Injury
Lutian Yao, MD, Elisia D. Tichy, PhD, Leilei Zhong, PhD, Luqiang Wang, Foteini Mourkioti, PhD and Ling Qin, PhD

Tendon & Ligament

Injury and Healing Effect on Fatigue Properties of Collagen V Haploinsufficient Female Murine Tendons
Jaclyn Carlson, MEng, Zakary Beach, BS, Stephanie Weiss, BS, David Birk, PhD and Louis Soslowsky, PhD

Determining the Roles of Decorin and Biglycan in Tendon Healing Using Conditional Deletion at Time of Injury
Ashley Fung, Stephanie Weiss, David Birk and Louis Soslowsky

The Differential Roles of Decorin and Biglycan in the Early Proliferative and Remodeling Phases of Tendon Healing
Thomas Leahy, BS, Ashley Fung, BS, Stephanie Weiss, BS, David Birk, PhD and Louis Soslowsky, PhD

Collagen V Deficiency during Healing Mitigates the Quasi-Static Mechanical Deficits of Injured Tendons
Ryan Leiphart, BS, Stephanie Weiss, BS, David Birk, PhD and Louis Soslowsky, PhD

Acute Reduction in Collagen V Expression Increases Viscoelasticity in Mature Tendons
Ryan Leiphart, BS, Stephanie Weiss, BS, David Birk, PhD and Louis Soslowsky, PhD

Role of Ligamentous Restraints During Anterior-Posterior Drawer Tests of the Murine Knee
Snehal Shetye, PhD, John Bova, BS, Andrew Kuntz, MD, Miltiadis Zgonis, MD, David Butler, PhD and Nathaniel Dyment, PhD

Knockdown of Collagen V during the Inflammatory Healing Phase Significantly Affects Quasi-Static Tendon Mechanics
Brittany Taylor, PhD, Ryan Leiphart, BS, Stephanie Weiss, BS, David Birk, PhD and Louis Soslowsky, PhD