Mark Amirtharaj, MD

Dr. Mark Amirtharaj is a fellowship-trained orthopedic surgeon at the HSS Sports Medicine Institute, specializing in hip, knee, and shoulder surgery. He is also an Assistant Professor of Orthopedic Surgery at Weill Cornell Medical College. Dr. Amirtharaj is committed to delivering personalized, cutting-edge care to each of his patients—from weekend warriors to elite athletes—helping them return to the sports and activities they love.

Dr. Amirtharaj holds an undergraduate degree in Electrical Engineering from the University of Maryland, College Park, where he developed a strong affinity for creating technology. He earned his medical degree from Georgetown University School of Medicine, where the principle of cura personalis—care for the whole person—deeply influenced his approach to patient care. He then did his orthopedic surgery residency at the University of Nebraska Medical Center. 

Following residency, he went on to complete a prestigious two-year fellowship in orthopedic sports medicine at the world-renowned Hospital for Special Surgery. During his fellowship, Dr. Amirtharaj trained alongside the top surgeons in the field, learning advanced techniques in arthroscopic surgery. He also served as assistant team physician for several professional teams including the New York Giants (NFL), New York Rangers (NHL), and New York Red Bulls (MLS), gaining firsthand experience in treating high-performance athletes.

With a background in engineering, Dr. Amirtharaj brings a unique perspective to orthopedic care, combining surgical expertise with a passion for innovation. He collaborates closely with the HSS Biomechanics Laboratory, pursuing various lines of research including joint computational modeling, ACL biomechanics, and the development of surgical planning tools. His work has been widely published in peer-reviewed journals, presented at leading national and international conferences, and recognized with several awards for excellence in orthopedic sports medicine. 

Outside of medicine Dr. Amirtharaj enjoys staying active and spending time with his wife, two kids and golden retriever.

Knee ligament injuries (ACL, PCL, MCL, LCL)
Meniscus injuries
Cartilage injuries
Knee malalignment, deformity
Patellar instability
Hip preservation – Femoroacetabular impingement (FAI), Hip dysplasia
Proximal hamstring injuries
Hip abductor injuries
Rotator cuff tears
Shoulder instability
Fracture care

Knee:
Knee Arthroscopy
ACL Reconstruction (adolescent and adult)
Revision ACL Reconstruction
PCL, MCL, Posterolateral Corner Reconstruction
Meniscus Repair
Cartilage Repair
High Tibial Osteotomy, Distal Femoral Osteotomy
Patella dislocation and MPFL Reconstruction, Tibial Tubercle Osteotomy
Robotic-Assisted Partial Knee Replacement

Hip:
Hip Arthroscopy
Hip Labrum Repair and Reconstruction
Proximal Hamstring Repair
Abductor Repair

Shoulder/Elbow:
Shoulder Arthroscopy
Rotator Cuff Repair
Proximal Biceps Tenodesis
Shoulder Labrum Repair (arthroscopic and open)
Distal Biceps Tendon Repair
Pectoralis Major Tendon Repair