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Double Board Certified in 

Anesthesiology and Interventional Pain Management

Dr. Christopher Chun has had extensive training and experience in the past. He completed an Anesthesiology residency and ACGME accredited fellowship in Pain Management at Loma Linda University Medical Center in Loma Linda, CA. He is double-board certified in Anesthesiology with sub-specialty certification in Pain Medicine by the American Board of Anesthesiology.


His specific areas of interest are in Interventional Pain Management (injections, procedures) and advancement in the field of Pain Management. He treats his patients using a multi-disciplinary approach to provide patient-specific compassionate care. Dr. Chun’s goals for his patients are to correctly diagnose, for them to understand the source and reason for their pain, know the different treatment options to help treat that source of pain, help them to function and work better, and obtain a better and improved quality of life.

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Double Board Certified in 

Anesthesiology and Interventional Pain Management

Growing up in the Midwest, Dr. Gumbrecht started his professional career as a mechanical engineer, specializing in the automotive industry and occupant safety. This opened many opportunities which included working with orthopedic surgeons and scientists in the hospital setting.  He eventually centered his focus as a Doctor of Medicine and completed his residency in Anesthesiology at Loyola University Medical Center Chicago.  Following residency, he completed his fellowship in Pain Medicine at Rush University Medical Center.  He is double board certified by the American Board of Anesthesiology (ABA) in Anesthesiology and in Pain Medicine.


Dr. Gumbrecht's approach to pain medicine includes a multifaceted method of counseling and educating patients of their diagnoses. He takes a tailored approach to their care and provides treatment options that may include therapy, medications, and interventional procedures.   This pathway has helped patients to manage their pain symptoms and rehabilitate into their functional lifestyle.


 His specialty focuses include Neuromodulation and Regenerative Medicine.

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Double Board Certified in

Anesthesiology and Pain Medicine

Dr. Chen grew up in the Midwest and attended Washington University in Saint Louis and studied chemistry to learn about the complexities of chemicals and medications. He studied the effects of sepsis on energy molecules in animal models with doctors from the school of medicine and department of chemistry.  He pursued a degree in medicine at the Penn State College of Medicine and attended residency at John's Hopkins Hospital in anesthesiology and critical care.  Following residency, he completed a fellowship in Pain Medicine at the University of Pennsylvania. He is double board certified by the American Board of Anesthesiology (ABA) in Anesthesiology and in Pain Medicine.

Dr. Chen has had over 24 years of experience and takes a multifaceted approach to identifying the root cause of a patients medical problems and attempts to provide a realistic solutions given the limitations or resources available.  He realizes that there are many challenges to medicine today and strives to be a patient advocate with the goals improving their activities of daily living as well as their quality of life.  

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Board-certified Neurological Surgeon by the American Board of Neurological Surgery 

Dr. Rubin specializes in disorders of the spine and treating patients suffering from pain or other symptoms affecting the low back, neck, arms and legs.  While Dr. Rubin utilizes the most up-to-date diagnostic and surgical techniques he still believes the most important part of medicine is communication with his patients. His goal is to help you understand the cause of your pain and all the available treatment options to formulate a treatment plan that is right for you. 


His career in neurosurgery started early. As an undergraduate student at the University of Virginia, Dr. Rubin worked with the Department of Neurosurgery researching treatments for victims of head trauma and shadowing busy neurosurgeons in the OR and clinic.  After graduating from the University of Virginia with distinction, Dr. Rubin attended medical school at the University of Southern California Keck School of Medicine. As a senior medical student he served as a mentor and tutor in anatomy, pharmacology, pathology and other subjects. He was awarded a USC Salerni Collegium academic scholarship and elected to the national medical honor society, Alpha Omega Alpha (AOA).


Dr. Rubin completed his neurosurgical training at the prestigious Weill Cornell New York Presbyterian and Memorial Sloan Kettering Cancer Center in New York. Weill Cornell Neurosurgery is consistently ranked among the very best in the nation in US News and World Report annual rankings. Throughout his career Dr. Rubin has been involved in neurosurgery research and has published a number of papers in peer-reviewed medical journals



                    Orthopedic and Spine Surgeon

 Fellow of the American Academy of Orthopedic Surgeons 

Dr. Saadi has 20 years of experience in orthopedics since 1999. While in practice, he has focused much of his on the utilization of state of the art technology to develop techniques using computer assistance and robotics to more accurately align and position joint replacement implants through minimally invasive exposures. This includes total and partial knee resurfacing, total hip replacement, and total and reverse shoulder replacement. He has been part of a design team for seven years culminating in the development and recent FDA approval of the first 3D planning and live comprehensive total shoulder computer navigation system in the world. 

In addition, his practice offers implantation of completely customized patient- specific knee replacements made using additive manufacturing technology - commonly known as 3D printing". He also uses computer assisted surgery technology for increased accuracy, efficiency, and safety in spinal operations to help minimize surgical exposure to trauma and improve recovery. He takes pride in helping patient choose among all of these technologically advanced options for knee, hip, shoulder, and spine problems to assists them in best addressing their condition. Dr. Saadi is a Fellow of the American Academy of Orthopaedic Surgeons.


There are currently two different types of doctors that are licensed to practice medicine: medical doctors, “M.D.s,” and doctors of osteopathy, “D.O.s.”  Both are fully licensed to treat patients, prescribe medication, and perform surgery.  The two are very similar, with individuals in both paths completing 4 years of undergraduate school, four years of medical training, as well as higher medical education designed to prepare them for their future medical specialty.  However, there are a couple of features that differentiate D.O.s from M.D.s.  In their medical training, a D.O. receives extra training in physical manipulation, and maintains a “hands-on” approach to the body and patient treatment.  An osteopathic doctor will attempt to treat the entire body, and utilize osteopathic manipulative treatment (OMT), to ensure that the body’s natural healing processes are working properly.  Both kinds of physicians use similar techniques and medical practices to treat patients.

After graduating from medical school, the new doctors spend anywhere from three to eight years in a “residency” program, where they will receive extensive training of a specific area of medicine in which they wish to practice.  After completion of the program, and passing general certification testing, they are then fully licensed to practice medicine.  After this, many physicians continue their education, going through a fellowship program to develop skills, and obtain “board certification.”  Both of which will ultimately allow the doctor to provide better care to their patients.  Fellowship programs usually last one to two years and provide advanced training in an area of medicine more specific than the initial medical residency.  The doctor may then receive board certification, indicating that the individual has gone “above and beyond” the basic medical requirements, and is allowed to practice without direct supervision in the specific medical field.

In the United States, medical board certification is not mandatory, and a physician may practice without certification in their specialty.  Basic medical licensure ensures that all doctors meet fundamental requirements to ensure patient safety and standards of treatment, but are not specific for each specialty. Board certification indicates a doctor’s expertise in a specialty or sub-specialty of medicine.  To be board certified, a physician must go through extensive peer evaluation by doctors already certified in the field, and testing to ensure the skills and practices continue to be exceptional.  While any doctor will provide treatment for a wide range of medical conditions, a board certified doctor is dedicated to providing outstanding patient care through rigorous voluntary advanced education opportunities.  A board certified specialist is an expert in medical science in his or her specialty as well as patient safety and quality healthcare.  The physician must learn about new technologies, continue to participate in professional development programs, and maintain certification through continuing education.

A physician may hold board certifications in multiple areas of medicine.  There are many areas of medicine that overlap and a doctor that is “double board certified,” has received training in two separate specialties that work synergistically to provide the highest level of patient care.  For example a physician may receive board certification in anesthesiology, and subsequently receive additional training and certification in pain management.  A medical provider that holds double board certification demonstrates that they are experts in multiple fields, and will utilize their advanced training in combination to address specific medical issues, resulting in a exceptionally advanced level of patient care.

The path to becoming a physician is rigorous and requires dedication, tenacity, and time.  However, even with similar medical education, there are dramatic differences in the quality of care that is provided by different doctors.  It is important to know about your personal physician and his background.  You can do this by researching your doctor and his board certification status, his rating on websites and publications, as well as reviews from their patients.  It is ultimately your decision who you chose for treatment, and it is important to be an educated patient, and visit a doctor that you know will provide the highest level of care possible.

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