Hyun Bae began his medical studies at Columbia University, where he graduated with a degree in biomechanics. Having interacted with numerous medical students in Columbia’s orthopaedics lab, he decided that orthopaedic medicine was the career path he wanted to follow. With his mind set on a life in medicine, he went on to earn his medical degree, cum laude, at Yale University School of Medicine. His career to date boasts an impressive list of research projects and achievements. Much of this has focused on intervertebral disc repair, while he has also carried out research on mesenchymal stem cells. His work has led him to challenge, where suitable, accepted or “tried and true” methods of treatment and to always strive for improved techniques and fresh ideas. He spoke to Spinal News International about his career highlights so far, and about what he believes the future holds for spinal medicine.
Why did you decide to become a doctor and why, in particular, did you decide to specialise in the spine?
My parents emigrated from Korea to provide a better education and opportunity for the family in the USA. I never did, nor was I allowed to, take that for granted. Like many immigrants I was very driven and ambitious, so being a doctor was always up there as an option since before I got into college. What really put the nail in the coffin for me was when I was studying biomedical engineering at Columbia University as an undergraduate, where I realised that what was waiting for me after graduation was not the career path I wanted for myself. At this time I was heavily involved in an orthopaedics research lab, still in the field of engineering, but enjoying mentorship from the many medical students who came and went from this lab. With one fell swoop I knew that I wanted to be a doctor and I knew what specific field I wanted to be in.
Who have been your career mentors and what wisdom did they impart?
Henry Bohlman was my director during my fellowship at Case Western Reserve University. He taught me that the spine was not like traditional orthopaedics—it required more thoughtfulness and more finesse, because you are dealing with the neural elements. In his time the field of spinal surgery was undergoing a renaissance. He not only taught me the science of spine but truly the art of spine care. He taught me that complications were always right around the corner and that preparation and diligence were paramount.
What do you think has been the biggest development in spinal surgery during your career?
I think it has been bone morphogenic proteins. I still find it incredible that we were one of the first and still few surgical fields that use recombinant proteins in surgery. I think the power of this technology is somewhat lost on the generation that does not have experience harvesting iliac crest for autograft. It is taken for granted now, but making bone out of really nothing is an incredible feat of modern day molecular medicine.
Outside of your own work, what has been the most interesting paper that you have seen in the last 12 months?
The Spine Journal ran an article by one of my past fellows—Nomaan Ashraf—about using stem cell allograft in cervical fusion. The paper showed that the use of allograft material enhanced with stem cells actually resulted in a lower fusion rate than of standard allograft in fusion. People automatically hear buzzwords like “stem cells” and expect instantaneous and superior results. This paper shows that these expectations may not be realistic.
Of the research you have been involved with, which piece are you proudest of and why?
My work in intervertebral disc repair has been a specific passion and singular pride of mine. It is incredibly challenging, but developing a biologic solution to disc degeneration would be greatly impactful.
What are your current research interests?
The above-mentioned research in intervertebral disc repair is always on my plate, and lately I have been specifically looking at using mesenchymal stem cells to achieve such repair.
What makes your work on intervertebral disc repair so challenging?
The disc is an amazing structure. With all discs combined, it is the largest avascular structure in the body. It is so challenging because the bioavailability and pharmacokinetics are so demanding. The disc has little to no blood supply and getting nutrients to the disc is incredibly challenging. The intradiscal pressure can be 15 times the normal blood pressure, and therefore getting any type of drug to be delivered through the capillary system, which is the typical drug delivery mode, is nearly impossible. That is why I think direct intradiscal injection is an advantageous mode of delivering therapy.
You have been involved in a lot of research on motion preservation technology. Why is this important and how do you see this area developing in the future?
Fusion is important and necessary, but it is absolutely a non-physiologic solution with severe limitations. With the approval of new minimally invasive techniques and devices to replace fusion procedures and preserve motion, more surgeons are realising that fusion may not be the best solution. It may not even be a good solution. A greater acceptance of motion preservation technology will really push the envelope for innovators to create and advance the field in the future.
As someone with a research background, what advice would you give to those starting out on their medical research careers?
First of all, I think people classify me as a researcher because I am involved in translational and basic science research. But I think the term research really means that you have an academic process in the way you go about obtaining and processing knowledge. We all do this by analysing outcomes and techniques in the effort to improve our skills and deliver better patient care. To me that is a form of research. I do feel that having some academic initiative or an academic reference in the way you go about treating your patients is very important. Whether you do basic science research or not, what is important is that you use academic rigor in the information that is presented to you. It is one of the most important things I try to teach to my fellows. I try to teach them to keep an open mind but to use academic rigor in everything that they read and everything that somebody tells them—make sure that you yourself have researched it before you actually apply that to patients and continuously review your results to make sure they match what you think you believe they should.
Basic science research and translational research require a significant time commitment. That is something that can be challenging in a busy clinical practice. If, however, one is up to the challenge it can certainly be incredibly rewarding as well.
What have you learned from attending scientific meetings? Do you think such meetings will continue to be important in the modern, technologically-connected world?
There is no question that there is great value in interacting with fellow scientists and peers at scientific meetings. Many new ideas and solutions to tough problems have come about thanks to these personal human interactions—you just cannot generate the same type of information exchange over the phone or via email. Perhaps in future there will be a more efficient venue for exchanges so interactions can happen more frequently and conveniently, such as using virtual venues—maybe with 3D or virtual reality glasses that will mimic the human-to-human experience.
What has been your most memorable case?
My very first case as a fellow at the VA was removal of a thoracic spine tumour. It was a patient with significant comorbidities including renal dialysis and who had not walked in over two weeks. He had a T8 lesion compromising his spinal canal. I did not have any experience performing a thoracotomy, let alone a vertebrectomy on my own. I presented it to Henry Bohlman hoping to get guidance and surgical assistance. I still remember the words like it was yesterday, he just said, “Wow. That really is a tough first case. Good luck!” I did a lot of reading that night.
What advice would you give to someone who was starting their career in spinal surgery?
Spinal surgery is fraught with complications. You need to have excellent indications because things do not always turn out the way you might expect. I would also say that it is important to always challenge the paradigm that fusion is the gold standard treatment.
What are the three questions in spinal medicine that still need an answer?
- Where is the pain generator?
- Can we improve on our current diagnostic tools in spine?
- Where do we draw the line between industry being involved and when do they become too involved?
What do you think is the role of industry in spinal research?
That is a really tough question. The industry has to have some involvement. I understand the sentiment that the industry can be too involved, but current non-industry funding sources are few and far between. The National Institutes of Health funding rate has dropped and is now below 10%. Therefore, the industry does and needs to play a vital role in funding research. Of course, an inherent interest exists, but many therapies and trials fail. I am currently involved in the Mesoblast mesenchymal stem cell study for intradiscal disc repair and there is no question that to run a phase I/phase II/phase III clinical study across many disease entities requires many millions of dollars. Ultimately the study could fail but if it is successful then many patients would stand to benefit as well as the sponsor. This is no different than any chemotherapeutic or other drug trials. Without a commercial interest, many fantastic drugs and therapies would not exist.
In terms of diagnostic tools, what developments are currently making the biggest difference?
I think in terms of diagnostic tools, what is happening in functional magnetic resonance imaging (MRI) in trying to figure the source of pain and how people respond to pain is certainly the most interesting.
I think as far as future developments go, spine imaging does need to take another evolutionary step. We need to take another step like the one we have taken from computed tomography to MRI, I to develop some kind of functional MRI that will decipher pain generated by intradiscal disease. Really, to find out what the pain generator is and what patients with disc degeneration truly have pain. Which patients have pain related to the disc and more importantly which patients do not. I think imaging that is truly correlated with pain will certainly be the next paradigm shift.
What do you think will be the next big development in spinal medicine?
Stem cells have an incredible potential to treat diseases, but until now it has seemed more science fiction than true science. We are still in the beginning stages of translating the promise of stem cells from the bench to the bedside. Hopefully in the near future we will be able to demonstrate true evidence-based efficacy of stem cell therapies not only for the spine but for other major diseases as well. When this occurs this will be an inflection point that defines the future of modern medicine.
Outside of medicine, what are some of your hobbies and interests?
Golf, tequila, my beautiful wife and my three wonderful, rambunctious daughters.
2012 Medical director, director of Spine Education Spine Center, Division of Orthopaedic Surgery, Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, USA
2009 Medical director, director of Research Center for Spinal Restoration and The Spine Institute Santa Monica, USA
2009–2012 Co-fellowship director Spine Center, Division of Orthopaedic Surgery, Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, USA
2001–2009 Director of research The Spine Institute at Saint John’s Health Center, Santa Monica, USA
2000–2001 Spine surgery fellowship, Case Western Reserve University, Cleveland, USA
1996–2000 Orthopaedic surgery residency, Hospital for Special Surgery, New York City, USA
1995–1996 General surgery internship, Northshore University Hospital, Manhasset, USA
1995 MD (Cum laude), Yale University School Medicine, New Haven, USA
1993–1994 Molecular and cell biology, NIH Howard Hughes Research Fellow, Howard Hughes Medical Institute, Bethesda, USA
1990 BS, bioengineering and biomechanics, Columbia University, New York City, USA
2010 Outstanding Paper Award, North American Spine Society
2005 Outstanding Paper Award, Spine Arthroplasty Society
2004 Outstanding Paper Award, Scoliosis Research Society
2003 Basic Science Grant Award, Cervical Spine Research Society
2002 DePuy Acromed Named Research Grant
1998 Eastern Orthopaedic Association Resident Research Award