Henry Ford Health System

Mark Pahuta

Stand up straight. It is a familiar cue that many of us have heard, at one time or another, while growing up, from our parents, teachers or, worse, both. Standing up straight showed that you were more self-assured, happy, and approachable. For slouchers,

it meant the exact opposite. Asaspine surgeon, I recognize that standing up straight is not easy for the patients that I see. Some patients suffer from a physical or medical ailment that makes standing upright difficult or impossible. Unfortunately, many others have lost their ability to stand straight after having undergone a spinal fusion for spinal stenosis, scoliosis, trauma, or cancer. This condition is called “flat-back” syndrome, and understandably, these patients are very upset because they had hoped the first surgery would have helped relieve their chronic spine symptoms.

For three reasons, the flat-back syndrome is disabling for patients. First, if you can’t see straight, you end up looking at your feet and can’t do what you need to do. Second, patients will try to bend their knees and hips to compensate, but this expends a lot of energy, and they can not tolerate this for the entire day. Third, the other joints in the body wear out faster and may need to be fused or replaced.

Fortunately, over the last decade, spine surgeons have started to better understand the geometry and measurements of normal posture. To date, spine surgeons have not had a good way to translate this knowledge into the operating room.

Rod and screw constructs have become the gold standard for many spinal fusion surgeries. The surgeon anchors screws to the patient’s vertebrae (spine bones) and then connects the anchors with rods. As the rod must be contoured to maintain a patient’s posture, this is where things can go wrong. Since there are no widely available tools to gauge how a contoured rod will impact on a patient’s posture, surgeons are forced to use the “eye-ball” method for rod contouring. This is not very accurate and causes many flat-backs. A better solution is needed.

To address this problem, I developed a technique for generating life-size and customized rod bending templates. First, I collected the best evidence on the geometry and measurements of normal posture through a systematic review. Using these data, I wrote a computer program that optimizes posture to maintain forward gaze and be energy efficient. The program uses patient-specific pre-operative plans for screw placement based on the patient’s CT and/or MRI images.

"Rod And Screw Constructs Have Become The Gold Standard For Many Spinal Fusion Surgeries"

Itake the sterile templates into the operating room and use them to bend the rodcorrectly. This is much like 3D printing - only in this case, it is two dimensional. Results from 30 cases have been promising so far. Using the software has made thesurgery more efficient with better outcomes. The next steps involve a study design using the software to examine cause and effect.

Spine surgery has developed a bad reputationin the media over the years. It’s seen as a risky gamble as to whether it will make patients feel better. I hope that this software leads to more patient-centered and reliable outcomes in reconstructive spine surgery