Surgery of adults with OI – Dr. Michael To
Interview with Dr. Michael T, University of Hong Kong and Shenzhen
In most countries, pediatric surgeons are not allowed to operate on adults with OI because of the way hospitals are organized. Usually, the surgery is performed by an adult physician who knows about one body part (like hip, fingers, knee, pelvis etc). What are the pros and cons of having OI-specialists, who can also operate adults? We asked three very experienced OI-surgeons for their opinion on this. Dr. Michael To from Hong Kong is the third one out.
Who are you and what is your connection to OI?
My name is Dr. Michael To and I’m a paediatric orthopaedic surgeon, working both in Hong Kong and Shenzhen. I graduated from the University of Hong Kong in 1999 and became a paediatric orthopaedic specialist in 2006.
I worked in the Duchess of Kent Children’s Hospital and Queen Mary Hospital in Hong Kong. I started helping patients with OI during my specialist training in 2000 in Hong Kong. Since 2012, I extended my practice to Mainland China in a city called Shenzhen. I communed almost every day between Hong Kong and Shenzhen to help develop a new hospital, the University of Hong Kong (HKU) Shenzhen Hospital, in Shenzhen. I started a multidisciplinary OI service in about 2014.
Tell us about your experience with OI!
I have managed over 1000 patients through various free consultations in remote areas and cities in China at which I did free consultations over the past 10 years. In my hospital, the University of Hong Kong Shenzhen hospital, I started to operate in 2014/15 and have treated roughly 500+ patients according to our hospital system. I have done roughly 620+ operations on OI at which majority involve single stage multiple-bone operations because the deformities usually are complex and involving both lower limbs. I also operated on OI scoliosis.
I also work closely with charitable foundations to seek fundings for the patients in need. Currently there are four foundations I collaborated with in both Hong Kong and Shenzhen.
In HKU, the skeletal dysplasia patients are mainly followed up by paediatric orthopaedic surgeons. Therefore, we have close relationship with both the patients and their family members. I operate on both children (age 0-18) and adults (age >18). The oldest OI patient I operated was >60. I cannot remember the exact age and she is now nearly 70.
What is the difference between operating children and adults with OI?
The difference is huge. Children’s fractures heal faster and surgical dissection is usually simpler. The operation time is usually shorter. But as they grow up, the dissection is more, blood loss is more and the operation time usually takes longer. The choice of implants are also different. In children, we use telescopic rods to accommodate the growth. In adults, we use locking nails instead. The scoliosis in children tend to be more flexible and may be easier to correct. But adults’ deformities are usually stiffer and more severe and the surgical dissection and recovery usually takes longer. But overall, the experience and outcome is usually very gratifying. 80% of my patients come from outside Shenzhen or Hong Kong. They travelled long distance to seek medical attention. Their problems may be fresh fractures or long standing deformities.
Do you sometimes refer to an adult specialist?
So far we have not referred or done any joint replacement surgeries for our OI patients. But I work closely with our adult trauma, spine surgeons and neurosurgeons as well. In my opinion, we cannot possibly know everything. We need to work with adult surgeons.
What are the pros and cons of having OI-specialists who can also operate adults?

In my opinion, OI is not just about bone fragility. It involves multiple organs and require the inputs from different specialties – dental surgery, ENT, geneticists, IVF, paediatricians, endocrinologists, rehab specialists…. Children are not small adults and certainly adults are very different from children. There should be a comprehensive care no matter if we are helping children or adults.
Many people may think treating OI is like treating adult osteoporosis, we as surgeons, we operate and let the endocrinologist or geriatricians look after the medical part. OI however, is a life-long disease. The relationships between the doctors and patients are lifelong. To me, everything started the moment the child was born. We as paediatric orthopaedic surgeons know about the patients and their families very well so that we know what the best for the patients may be. As we become more subspecialized (knee, hip, hand, spine, or pelvic surgeons), we may miss out areas that we are not familiar with and we (superspecialists) may not be able to provide the most comprehensive care for our patients.
There are lots of medical advances every day, the skills and treatments in different subspecialties are also advancing. These skills and knowledge may be useful in the treatments of OI where there are still many unanswered questions. An OI specialist can help to connect dots!
Should we advocate for pediatric surgeons doing surgery on adults with OI?
I think there are advantages for paediatric orthopaedic surgeons to operate on adult OI patients especially if the patients have been followed up for a long period of time. But there are also issues related to the government policy, insurance, etc.
Could one solution be a collaboration?
Collaboration between adult and paediatric orthopaedic surgeon is a good model in helping patients with OI. The paediatric orthopaedic surgeons may have more experience looking after the patients for years and know them inside out. The adult surgeons have more experience in adults and in fact many of the skills in treating children and adults are very different. It is certainly a win-win for patients.
Do you belong to any international networks?
I am a member of the Scoliosis Research Society, Asia Pacific Orthopaedic Association, Hong Kong Orthopaedic Association, and SICOT. Currently, OI surgeons from North America, Europe, Asia including Richard Kruse, Pejin Zagorka, RJB Sakkers, TJ Cho and many others around the world have formed an International OI Surgeons Study Group and we meet regularly online to talk about OI patient management. Our last meeting talked about pelvic deformities in OI. This can definitely improve our knowledge.
Anything you think we should have asked about?
Over the past 20+ years of medical practice, OI is one of most challenging diseases I managed. Not just the long bone deformities, but the spinal deformities and many non-orthopaedic challenges. I think my patients have made me become a better doctor. I work closer with experts from different disciplines e.g. dental surgeons, prenatal diagnosis, paediatricians, IVF doctors… to provide better holistic care of the patients.
I also work with patient organisations, charitable foundations and governments to improve the patient care. Through these outreach services to remote areas, I have met many patients with rare bone diseases who may lack medical and financial support. I am also grateful to have the opportunity to meet and work with many patients and experts around the world.
Check out the Interviews with Dr. Guus Janus from the Netherlands and Dr. Jeanne Franzone from the USA.