is a fellowship trained, board-certified orthopedic surgeon who specializes in knee, shoulder and elbow conditions. He is a nationally recognized leader in sports medicine and knee and shoulder surgery. Dr. Delos has over 30 peer-reviewed articles and more than 50 national and international presentations. He has authored or co-authored more than five textbook chapters.
Dr. Delos has a particular interest in minimally invasive methods of shoulder surgery and complex knee preservation surgery, including revision surgery for torn ligaments, meniscal and cartilage transplantation, and joint replacement (both partial and total). Also, he has a particular interest in biologic forms of treatment, such as platelet rich plasma (PRP) and stem cell therapy, and has conducted seminal research on the topic.
Further, as an athlete whose playing career was affected by a serious knee injury, Dr. Delos works with competitive athletes and weekend warriors to help them achieve their goal of returning to highest levels of activity possible. He has extensive experience caring for athletes of all competitive levels, including professional, college and high school athletes. He is a former assistant orthopaedic surgeon for the NY Giants Football team and is currently the team physician for the Purchase College Athletic Department and the Westchester Flames semi-professional soccer team. Dr. Delos also serves as a team physician for many local high schools, including Greenwich High School and Iona Prep.
I have had several significant orthopedic procedures and, after a bike accident, decided to try ONS and Dr. Delos after hearing so many good things. Every aspect of my treatment was IMPECCABLE including: Speed to first consultation (same day); speed to surgery (would have been next day but had to wait a week due to COVID testing); never waited more than 3 minutes on any visit; first class surgical center in Stamford; professional and compassionate interaction with Dr. Delos, never late, never rushed, very clear and helpful answers to every question, no doubt that at the time you are with him you are his number one priority. ONS is a first class operation that clearly takes great pride in every aspect of their treatment. As a patient, what is most important to me is great medical care. It was a surprising bonus to also receive a truly first-class customer experience every step of the way whether at check in, radiology, pre-operative procedures, appointment scheduling, etc. (5 Star Review on Healthgrades)
I had both knees replaced by Dr Delos in June and was back to work full time in 3 weeks. By 6 weeks i was walking like a track star and nobody could tell that i ever had surgery. If you are considering a knee replacement run, don’t walk, and go see Dr Delos! (5 Star Review on Healthgrades from B.H.)
The ONS surgical team, physical therapy team and admin are all amazing. I had the good fortune of working closely with Dr. Delos and Tanya K., DPT (Greenwich PT Director), and they, and all on their team/staff were kind, knowledgeable, professional, efficient – – and it is clear they genuinely care about their patients and their improvement! They also give you the confidence and support you need to get through your recovery. From the moment you hobble in the door to the moment you walk out (better than ever), each member of the team makes a point get to know and be there for each individual client – particularly, so if you have a question or any need anything at all, someone on the team can assist you promptly/safely. They definitely go above and beyond in their patient care and it shows in the results! I never expected my recovery to be so pleasant and faster than expected! (5 Star Review on Google from S.S.)
Dr. Delos explained my displaced meniscus injury and his recommendations for fixing it so that I could get back to doing what I could before. He was very clear and very positive in his description, diagnosis and surgery to be done. I had been suffering for over a month and received several other recommendations from another doctor. I felt confident that the surgery he recommended would fix the issue. He also was able to get me in for the surgery within the week. Arthroscopic surgery went well, physical therapy went well and I was able to walk without a cane and drive in 2 weeks. No pain after surgery. It was important to get to PT quickly after surgery and to follow the plan outlined by the therapist. I would recommend Dr. Delos for a knee injury. (5 Star Review on Healthgrades, Aug. 6, 2019)
I recently had my ACL done by Dr. Delos. It was a great experience and the surgery went really well. I am really happy with how it is healing and how quickly I was able to get back to regular life.
Dr. Delos operated on my biceps as I ruptured it at the elbow. From initial consult to surgery to follow-ups, everything went fantastic. He explained everything, appointments were quick and easy and I couldn’t have been any happier. I would highly recommend him!!! (Five Star Review on Healthgrades from JA)
Dr. Delos changed my life! I went into my first appointment not knowing what to expect, and truly scared. He was kind, understanding, and extremely knowledgeable of my situation. I went in thinking my knee was dislocating, and after ten minutes of talking and examining my knee, Dr. Delos explained to me that my knee cap was dislocating, making it looser each time. I had surgery a month later and now I feel so much more secure! I can do everyday activities with ease, whereas before I was scared to even walk. I highly recommend Dr. Delos! He was amazing in every way! (5 Star Review on Healthgrades from B.A., Jul 2, 2019 )
Dr. Delos is wonderful. I went to him as a second opinion about my knee osteoarthritis. After that meeting, I knew I needed to have him do my surgery. I’m only 4 weeks out, but there is a positive difference already. I was scared to death if the total knee replacement and he made it so much easier for me. Dr Delos takes pride in his work which shows in the results, thank you Dr. Delos! (Comment on Instagram from E.F.)
Dr. Delos is an amazing man and surgeon. I had concerns about another physician that I was going to and heard great things about Dr. Delos, so I went to him for a second opinion. He was completely straight with me and reviewed everything with me. I didn’t feel the least bit rushed. He took all the time that I needed. I walked away knowing what was wrong with my knee and subsequently, chose him for my total knee replacement. His bedside manner is wonderful and he is compassionate, caring and confident. He made sure that I knew exactly what was wrong and how he would treat it. I had ad my surgery and am 6 weeks out. I’m already driving and back to work! His office staff are all great, and my PT is going well. They are all so supportive, as Dr. Delos is. I would recommend him to anyone. I can’t say enough wonderful things about him. Thank you Dr. Delos!!!!!! I’m a new woman with a brand new knee!! (5 Star Review on Google from E.N.) 07/10/2019
Dr Delos is the best! He performed surgery on my shoulder after a car accident and it’s 100% better! No pain and absolutely no problems after the surgery. He recently did a total knee replacement for me. I was in excruciating pain before the surgery. He was so compassionate with me. I could truly feel he felt my pain and wanted it to go away. He wanted the best for me and that’s exactly what he did for me! I’m completely pain free, have absolutely no problems with my knee now. He gave me my freedom back. He is a wonderful, caring, skilful, and knowledgeable doctor. I can’t say enough about him! I highly recommend him, as I said, he is the Best! (5 Star Review on Healthgrades from E.O.)
Dr. Delos is a great doctor. He performed surgery on my shoulder after massive injuries. There was no pain, and it healed very well. He takes his time when he talks to you and answers all questions. I am very pleased with his work. (Five Star Review on Healthgrades from L.B)
was fantastic. He made an expert repair on my torn tendon and the follow up and follow through with the Dr. and with ONS PT
was outstanding. (5 Star Review on Healthgrades from J.M. Jul 30, 2019)
Dr. Delos is an excellent person and doctor. Always on time for appointments. Awesome bedside manners. I never felt rushed. Always took the time to answer all of my questions. The facilities and staff were equally professional. (5 Star Review on Healthgrades) September 11, 2019
My son had a torn ACL. Dr. Delos is a great doctor, surgeon and has wonderful communication skills. Highly recommended. (5 Star Review on Google from C.R.)
My experience with ONS and Dr. Delos has been outstanding in every way. I had been suffering with osteoarthritis in my knees and was looking for a second opinion. During my first appointment with Dr. Delos and after his review of my x-rays and my medical history, he thoughtfully explained all of my options and we worked together to determine next steps. My condition was advanced and I had already tried medication and physical therapy which had not relieved my pain. I tried cortisone injections next, but this too proved to be of limited value and my ability to walk and degree of pain worsened. I ultimately decided to request bilateral knee replacement. Again, Dr. Delos went over everything with me in a patient and clear manner with all of the risks and benefits identified. I felt confident and prepared after our appointment and I knew that if I played my part both in prepping for and participating in the hard work after surgery, that I could return to a normal life. The entire ONS team was incredibly organized and helpful in every way. In no time, I was scheduled for surgery, booked for a pre-surgery class and all my questions were answered. Each person I interacted with was friendly, competent and caring. My surgery at Greenwich Hospital was a complete success. Dr. Delos and his team did an amazing job and the staff at the hospital was fantastic. I could not have asked for more. Today, 5 months after surgery, I am walking normally and without pain. I am continuing to exercise and follow the advice provided by my physical therapists and with each month that goes by I continue to be amazed at how different my life is than it was at this time last year. This surgery gave me my life back and I am forever grateful to Dr. Delos and his team of dedicated professionals for making that happen. (5 Star Review on Google from E.R.)
After years of PT, 2 surgeries that did not help, & numerous steroid injections I finally found ONS & Dr Delos. I WISH I had found him earlier! He listened to my story, understood MY situation & MY needs, evaluated MY condition & found a solution. He presented options & explained them all thoroughly. We made the decision together to undergo a partial knee replacement & WOW what a difference. At 7 months I walked a half marathon with NO ill effect, & I am back bike riding and hiking. And did I mention that this was an opioid free surgery – I did not need ANY strong painkillers – even in the hospital, I felt very little pain at all, I was only taking Tylenol!!! And as for the scar on my knee – what scar – you can barely see it! Thank you ONS and Dr Delos. (5 Star Review on Google from G.W.)
Dr. Delos performed ACL repair surgery as well as a meniscus repair after a ski accident in March 2018. Dr. Delos is not only an excellent surgeon, but also a caring and concerned doctor. I highly recommend him to anyone considering any type of knee surgery. I am almost back to my full strength and am forever grateful to Dr. Delos and the Physical Therapy team at ONS. (5 Star review on Healthgrades from M.R. in Riverside, CT)
Dr. Delos is an outstanding man, doctor, and friend. He helped save my leg and got me back on the field way quicker than anyone expected. Would recommend him to anyone who is looking for an orthopedic surgeon in Fairfield County, CT. One of the best around. (5 Star review on Healthgrades from P.)
Dr. Delos diagnosed my torn ACL and suggested reconstructive surgery using a part of my hamstring. I was reluctant to commit to surgery because of friends who had horror stories (with doctors in different practices), however Dr. Delos talked me off the ledge several times, boosting my confidence. Everything went seamlessly and his bedside manner both before and after the surgery was extraordinary. I couldn’t recommend him and the ONS team enough! (5 sSar review on Healthgrades from S.O. in Stamford, CT)
I was very pleased with the surgery Dr. Delos performed on my knee. I did not feel much pain at all after the surgery. I was walking normally in less than a week after my surgery. Dr. Delos was also very accommodating in that he used my MRI report from another center and didn’t make me do a new one, which saved me a lot of time. The office staff was also very good with all the follow ups and setting up appointments. Highly recommend Dr. Delos for knee arthroscopy. (5 Star review on Healthgrades by R.J.)
Dr. Delos was very helpful in determining expectations on the recovery time and reassuring that the whole process would go without a hitch. (5 Star review on Healthgrades from S.B. in Old Greenwich, CT)
Overall – very pleased. Great bedside manner and professional. Great surgeon and follow up post-surgery. Always available when needed as well as attention to detail. Listens to concerns and needs. Have recommended to friends and would go back. The staff at ONS was amazing also. (5 Star Review on Healthgrades from S.A.)
In a little less than two years ago, I had a small accident and broke my right shoulder. I had been seeing another physician for almost five months and my shoulder still wasn’t healing. The physician had tried of number of different things but nothing seemed to help. Needless to say my frustration level was over the top. Being right handed, many things in my life were quite difficult especially since my job requires me to type a lot on a computer. I had just seen the physician for an appointment and he wanted to wait a few more weeks to see if what we had been trying for months might finally work to get my bone to heal. A member of my family convinced me to see a doctor in the ONS practice because they had helped him a few years earlier. I made an appointment for Friday, July 29 with Dr. Delos. I met with him and conveyed my overwhelming frustration and I needed something done quickly. After reviewing my case and seeing the other things that had been tried, he realized surgery was the only option left. I agreed but told him it needed to be done as soon as possible because in six weeks I was going away and needed to be well on the way to being healed by then. Well, he and the staff took my request very seriously and started jumping through hoops to get me in for surgery. The staff was very helpful in getting everything together. Everything about the surgery was explained so I understood the procedure and recovery very well. Well, five days later on Wednesday, August 3, I was in Greenwich Hospital getting my surgery. The surgery was a total success. All my follow ups went well and the staff took great care of me. I would easily recommend ONS for any orthopaedic needs, big and small. Thank you. I can’t explain how good it was to get back the use of my arm. (F.V.O, 5 star review on the ONS Facebook page)
I had a bilateral knee replacement in May of this year and I could not be more pleased. While there was some concern about doing both knees at the same time, the procedure went extremely well and the recovery has been all I could have hoped for. I would highly recommend Dr. Delos for this procedure. If possible, he exceeded my expectations. (5 star review on Healthgrades from a patient in Stamford, CT)
Dr. Delos is a wonderfully gifted orthopedic surgeon who is also incredibly compassionate and personable. He instills a well-deserved sense of confidence in his patients, and even has a sense of humor! Dr. Delos surgically repaired my fractured collarbone by affixing a metal plate. The fractured bone and surgical wound healed completely without complication and post-surgery pain was well-controlled and never an issue. I highly recommend Dr. Delos and the highly efficient staff at ONS. (Five star review on Healthgrades from a patient in Port Chester, NY)
Dr. Delos recently performed arthroscopic knee surgery for a torn meniscus. I was pleased by his conservative approach to addressing my injury with a plan I was comfortable with. I started with Physical Therapy first, and then ultimately surgery. He thoroughly explained what the surgery would entail, the recovery process and set a realistic expectation of when I could return back to exercising. (Five star review on Healthgrades from M. in CT)
Dr. Delos is an awesome surgeon. He performed a knee replacement for my husband. Could not have had a better surgeon. Dr. Delos also helped our daughter who was injured in Canada with a fractured hip. His approach to her was so positive, and he was extremely honest with her prognosis as long as she followed his direction. She is now doing full marathons and an Ironman. All of this was because of Dr. Delos. He is the best surgeon I have ever met. His people skills are beyond reproach as well as his office staff. (Comment from Rate MDs)
I broke my shoulder and arm and Dr. Delos was brought in to operate on me. He’s got a wonderful manner about him and he’s an excellent doctor who follows up with his patients. (comment from Health Grades)
Dr. Delos is a very competent and caring surgeon, who is respectful of his patients as well as their time. He is knowledgeable and capable as well as kind. He operated on my broken ankle and I had an excellent results. (comment from Health Grades)
If it wasn’t for Dr. Delos I would not be walking without pain. I am almost 7 months out from TKR and I feel great!!! I am back to my normal routine. Dr. Delos’s bed side manner is fabulous. He is caring and listens to what you have to say. I recommend him all the time when people ask who did my surgery. (comment from Health Grades)
I broke my knee cap in 7 pieces. Dr. Delos repaired my knee with such expertise that I have healed quicker than expected. His professionalism is excellent and I would recommend him to my family and friends. (comment from RateMD)
Dr. Delos is not only an exceptional doctor, but he is caring and compassionate. My daughter had a torn ACL and Meniscus and was scheduled to compete in Disney. Dr. Delos worked with her to assure she could take the mat and compete prior to her surgery. He was factual but understanding of the opportunity she had in going to Disney. I would recommend him to EVERYONE in need of his specialty. (comment from RateMD)
Young, innovative, and on the cutting edge of his specialty. Dr. Delos replaced both my knees and I had wonderful results with minor pain, minimized by his phenomenal anesthesia formula. Best of all, the lack of external stitching (using medical glue instead) eased the healing process and left no ugly scarring. I could not ask for better results. Highly recommended by HSS and deservedly so. Thanks Dr. Delos. (comment from RateMD)
Dr. Delos and the entire staff at ONS are and always have been so friendly and professional. I cannot say enough positive things about him and will gladly recommend him and ONS to any and every one! Thank you all so much! (D.P.)
Dr. Delos has been an excellent physician throughout. I always felt like we were in this together. (Patient Survey)
I’ve had my share of experiences with orthopedic surgeons. But I must say Dr. Delos is by far one of the best if not the best doctor I’ve ever been to. He strives to do the best for you and your recovery. Thank you for all of your help Doc because of you I can go back to my normal life. God bless you this and every day. (R.M.)
For 21 year old S.R. the first game of the Division III soccer season at SUNY Purchase was her last. She twisted her knee awkwardly while running down the field and tore the anterior cruciate ligament (ACL) in her knee. She knew the ordeal she was in for, having torn the ACL in her other knee four years earlier while playing high school soccer. “I knew there would be surgery and six months of rehabilitation, but it was my senior year and I was determined to be back in shape to play lacrosse in the spring,” she said.
With the help and guidance of sports medicine specialist, Dr. Demetris Delos, S.R. achieved her goal. Not only did S.R. contribute to her team’s 9 and 3 season, she was named MVP of the team, and Female Athlete of the Year by the university. She also qualified for the First Team All Conference and All Regional in lacrosse.
“Dr. Delos was so nice and friendly and straightforward in terms of expectations and recovery time. He turned a bad situation into a great experience.” (S.R.)
12 year old soccer player, Sam M., was on top of his sport when he developed knee pain and swelling after a fall during a game last June. He kept it to himself because he didn’t want to jeopardize his chance to compete internationally at the Madrid Cup in September. Although he did make it to the tournament, he spent most of his time on the sidelines with his knee too painful, swollen, and difficult to move.
Upon returning home, Sam’s mother, Paula, brought him to see Dr. Demetris Delos, a sports medicine physician who specializes in knee injuries. Dr. Delos ordered an MRI, which revealed a slight fracture in Sam’s knee and a one inch piece of loose cartilage that would require surgery to repair. The injury was close to the growth plate, which could have had long term consequences. However, the surgery went well and Sam is back on the soccer field with his sights on the Hackley School’s Academy Team.
“Dr. Delos was always positive and everything he said would happen transpired, “said Paula M., Sam’s mother. “I was very impressed with the high level of care and collaboration with the physical therapists because they all wanted Sam to achieve his goal. Everyone was unbelievably caring.” (S.M.)
When my arthritis got so bad that I couldn’t walk, I knew I needed to have my right knee replaced. I went to ONS because my daughter had been treated by Dr. Camel and Dr. Sahler, and I was very impressed by how supportive and caring they were. As soon as I met Dr. Delos, I had every confidence that I was in good hands. He has a great bedside manner, he’s honest and straightforward. He took the time to answer every question my husband and I had about the procedure. Two months after my surgery, I was able to take a trip to Cancun and walk around the Mayan ruins and the only thing that bothered me was the heat. I’m going to Disney World next month, and I can’t thank Dr. Delos for making it all possible. I recommend ONS to everyone. (S.S.)
In July of 2014, Dr. Delos performed ACL surgery on my daughter. Brooke is doing great! In fact, since surgery Brooke has returned to playing volleyball & basketball. She played Varsity Volleyball from Stamford HS where she was a setter. She also played Varsity Basketball where she was the starting point guard. Both teams had a great year, but the girls basketball team had a historical year. The Stamford Knights won the FCIAC Title (District title) and the CIAC Title (State Championship.) Thanks to Dr. Delos, Brooke was a huge part of the team’s success. (C.K.)
I came home from my vacation in the Dominican Republic with two broken shoulders. Dr. Delos was absolutely amazing. He has a kind and caring bedside manner and when he told me I needed surgery on my left shoulder, I never had a thought to go anywhere else. I highly recommend him. (J.R.)
In 2014, local student athlete Brooke was playing basketball with her team in the 7th of 8 games at the AAU Nationals when she became injured during a layup after another player collided with her causing immediate knee pain. “I fell down and the trainer helped me off the court. We could see instant swelling and knew I needed to see a doctor” said Brooke.
Brooke suffered a painful injury which required surgery. ONS orthopedic surgeon Demetris Delos, MD performed surgery to repair a torn ACL and a partial meniscus tear. Brooke said, “I felt a little bit timid before the surgery but the surgery went well.” (more…)
Dr. Delos operated on my broken ankle 6 months ago and today I have graduated and am doing great! My experience was very good at ONS and I have a healthcare background so I am very picky when I choose a doctor. The ONS office is extremely well-run and the ambulatory care center is top notch. I’m not sure how they could do a better job and they called me the next day to see how I was doing after surgery. I’ve referred friends to ONS in the past months that have seen other specialists at ONS who have told me they have all had the same experience. I’ve even brought my daughter here for care. Dr. Delos is very knowledgeable, competent, and caring. (M.S.)
I had a full tissue tear of my rotator cuff. Dr. Delos examined me and pointed out the alternatives and how we could approach the injury. He explained his plan and operated to repair the damage at the ambulatory center. The experience was very good and they called me the next day to see how I was doing.
I needed physical therapy 3 days a week for the first few weeks, then twice a week and now I so much better six months later. (more…)
ONS is excellent! The staff is warm and very nice to children. I injured myself at work and came to see Dr. Delos. He explained that I needed surgery and it was scheduled at the Holly Hill Ambulatory Center. ONS and surgery center staff are lovely people. Dr. Delos was very human and made sure to explain all that I needed to have done to get back to normal. It was a perfect experience and I am pain free. (I.K.)
Dr. Delos, – “I was new customer at ONS. The staff showed me that they are really professional and made me feel comfortable, that they were reliable and it felt like home. Thanks everybody!” (Anonymous)
Everyone at ONS was very warm and friendly. Dr. Delos was extremely helpful and very direct with his thoughts and recommendations, which I liked! (Anonymous)
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Dr. Delos was incredibly helpful and knowledgeable. He diagnosed my son’s Lyme disease almost immediately and this was confirmed by testing. (Anonymous)