Steven M. Koehler, MD

As Chief of Adult Reconstruction at Montefiore, Sun Jin Kim, MD, specializes in adult reconstruction, primary and revision hip and knee replacements, nonoperative management of hip and knee arthritis. He is well versed in patient-specific technology, minimally invasive approaches, and blood-conserving surgical options. He also serves as an Assistant Professor at our Albert Einstein College of Medicine. Dr Kim received his medical degree from the prestigious Honors Program in Medical Education at Northwestern University's Feinberg School of Medicine in Chicago.

Daniel Berman, MD, is an attending orthopedic spine surgeon at Montefiore Einstein and Assistant Professor, Orthopedic Surgery at our Albert Einstein College of Medicine. Dr Berman has a clinical focus in minimally invasive endoscopic spine surgery as well as complex, adult spinal deformity and revision operations. After completing his Bachelor of Arts in Chemistry at Cornell University in 2014, Dr Berman attended Eastern Virginia Medical School, completing his Doctor of Medicine in 2019. He came to Montefiore Einstein for postgraduate training, completing his orthopedic surgery residency in 2024. In 2025, he completed his orthopedic spine fellowship at Mount Sinai School of Medicine.

David Gonzalez, MD, is a board-certified orthopedic surgeon specializing in treating sports injuries. He is an expert in performing arthroscopic shoulder and knee surgery, including rotator cuff repair, instability repair, labral repair, meniscal tears and the treatment of associated conditions. He is the Director of the Sports Medicine section and serves as an Assistant Professor of Orthopedic Surgery at our Albert Einstein College of Medicine. Dr Gonzalez is a member of the American Orthopedic Society for Sports Medicine and the American Academy of Orthopedic Surgeons and is a diplomate of the American Board of Orthopedic Surgery.

Jonathan Krystal, MD, joined the Department of Orthopedics at Montefiore in August 2017 as a spine surgeon and attending physician. He specializes in treating diseases of the spine. Dr Krystal earned his medical degree from University of Connecticut School of Medicine and completed a residency in orthopedics at our Albert Einstein College of Medicine. He followed that with a fellowship in spine surgery at the Rothman Institute at Jefferson University Hospitals in Philadelphia. Dr Krystal’s research has focused on spinal diseases, particularly on the use of advanced technologies such as radiosurgery to treat them. He is a member American Academy of Orthopedic Surgeons and the American Medical Association.

Yossef Blum, MD, is a board-certified orthopedic surgeon with a focus in primary and revision hip and knee replacement, as well the nonsurgical management of hip and knee arthritis. He specializes in less-invasive techniques, blood conserving options, advanced pain management, custom joint replacement, and partial knee replacement. Dr Blum currently serves as Assistant Clinical Director of the Joint Replacement Center. Dr Blum received his B.A. at Yeshiva University, where he was class valedictorian. Dr Blum received his medical degree from the University of Pennsylvania School of Medicine.

Benjamin Berenfeld, MD, specializes in upper extremity surgery and is one of the few specialists in Westchester and the Bronx performing endoscopic carpal and cubital tunnel releases and wrist arthroscopy. His clinical practice also encompasses a wide variety of nonoperative treatments, including collagenase injections for Dupuytren?s disease and the use of ultrasound guidance for joint injections with particular expertise in minimally invasive management of various disorders of the hand, wrist and elbow. At our Albert Einstein College of Medicine, he serves as an Assistant Professor.

Eli Kamara, MD, is an Orthopedic Surgeon at Montefiore Einstein and an Associate Professor at Albert Einstein College of Medicine. He specializes in adult reconstructive orthopedic surgery, mainly hip and knee replacements. He also focuses on primary joint replacement, as well as revisions of hip and knee arthroplasty, anterior hip arthroplasty, partial knee replacement, knee arthroscopy, and fractures of the lower extremity. Dr Kamara received his Doctor of Medicine at Albert Einstein College of Medicine and completed a residency in Orthopedics at Lenox Hill Hospital in New York City. He then completed a fellowship in Adult Reconstruction at the University of San Francisco School of Medicine.

Eloy Dario Tabeayo Alvarez, MD, is an attending physician in orthopedic surgery at Montefiore-Einstein. Dr Tabeayo Alvarez’s clinical focus is on the treatment of hand, wrist, elbow and shoulder injuries. He began his medical education in Spain. After earning his Bachelor degree from Instituto Rosalía de Castro, Dr Tabeayo Alvarez attended Universidade de Santiago de Compostela, earning his Doctor of Medicine in 2011. He continued with medical training in Spain, completing a six-year residency in orthopedic surgery at Hospital Universitario La Paz, Madrid, in 2017.