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Steven Mattheos, M.D.


Shoulder & Knee


Arthroscopy & Sports Medicine

About Dr. Mattheos

Dr. Steve Mattheos is a board-certified and fellowship-trained orthopedic surgeon at Sports Medicine North. He specializes in minimally-invasive surgical techniques involving the knee and shoulder. Dr. Mattheos’ clinical interests include arthroscopic and robotic surgery of the knee and shoulder.

A graduate of Amherst College and University of Massachusetts Medical School, Dr. Mattheos completed his orthopedic surgery training at the Harvard Combined Orthopaedic Residency Program, which included Massachusetts General Hospital, Boston Children's Hospital, Brigham and Women’s Hospital, and Beth Israel Deaconess Medical Center. He then completed a fellowship in sports medicine at New England Baptist Hospital in Boston, where he was involved in caring for the Boston Celtics.

He was raised in Lowell, Massachusetts, and graduated valedictorian of Central Catholic High School in Lawrence, Massachusetts. He speaks Greek fluently. He has been a speaker at multiple conferences, predominantly on topics involving meniscal repair, ACL reconstruction, calcific tendonitis of the shoulder, and robot-assisted partial and total knee replacement. He has been instrumental in bringing the robotic technology as it relates to orthopedic surgery to the North Shore of Massachusetts. Through the use of these technologies, Dr. Mattheos is able to create virtual preoperative treatment plans to better predict surgical outcomes and then execute those plans in the operating room. This form of precision medicine leads to more personalized care and more predictable outcomes for patients. He utilizes such techniques for treating orthopedic problems related to sports, as well as work-related injuries, traumas, and degenerative conditions, like arthritis.

In addition to his responsibilities at Sports Medicine North, Dr. Mattheos is the team physician for several local high schools, including Newburyport High School and Central Catholic High School.


Postgraduate Training

  • Sports Medicine Fellowship: New England Baptist Hospital, Boston, MA, 2008 – 2009
  • Orthopedic Residency: Harvard Combined Orthopaedic Residency Program, Boston, MA, 2003 – 2008


  • Doctorate of Medicine: University of Massachusetts Medical School, Worcester, MA, 1999 – 2003
  • Bachelor of Science in Biology: Amherst College, Amherst, MA, 1993 – 1997
  • Central Catholic High School, Lawrence, MA, 1989 – 1993


  • American Board of Orthopaedic Surgery

Professional Memberships

  • American Academy of Orthopaedic Surgeons (AAOS)
  • American Medical Association (AMA)
  • American Orthopaedic Society for Sports Medicine (AOSSM)
  • Massachusetts Medical Society (MMS)
  • New England Hellenic Medical and Dental Society (NEHMDS)

Sports Medicine Fellowship-Trained at New England Baptist Hospital

  • ACL (anterior cruciate ligament) reconstruction of the knee
  • Allograft cartilage reconstruction
  • Arthroscopic Acromioclavicular joint reconstruction
  • Arthroscopic repair of ligaments after shoulder dislocation
  • Arthroscopic rotator cuff repair
  • Arthroscopic labral and SLAP repair
  • Arthroscopic subacromial decompression
  • Arthroscopic treatment of all shoulder and knee injuries
  • Cartilage restoration procedures of all joints
  • Complex knee ligament (PCL, MCL, LCL) reconstruction
  • Knee arthroscopy
  • Meniscal repair and knee preservation
  • Microfracture cartilage restoration
  • Robot-assisted partial and total knee replacement