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Elegance in Spine: Extracavitary Approaches
The delicate task of dealing with spinal problems is getting a bit less complex, says Dr. Francis Shen. Orthopedists can now remove a section of rib and approach the front of the vertebrae from the back in an oblique direction.

Endotec Beats FDA, Strikes Blow for Innovation
Endotec has struck a blow for every orthopedic surgeon who wants to develop a better device. See how the company’s founders took on the FDA and got a federal judge to charge the agency with “stymieing progress and technological advancement.” How did they do it? Read on.

From Obesity to Osteoarthritis, the Carpal Tunnel Connection
It’s certainly no surprise that Carpal Tunnel Syndrome (CTS) is an exceedingly common orthopedic malady. But, as PearlDiver’s data show, the linkage between obesity, osteoarthritis and other conditions to CTS is most surprising. Check it out.

Using DNA to Predict Scoliosis
Six million people (estimate from the National Scoliosis Foundation) have scoliosis in one form or another. The primary age for onset of idiopathic scoliosis is 10-15 years old. Finally, there is a test which can reliably predict scoliosis. Fewer X-rays. Lower cost. Better outcomes.

New Capital, New Science for Cartilage Repair
$36 million invested in the last couple of months. TiGenix has more than that in the bank to fund market penetration. Then a new paper last week finds molecular cause of OA. Cartilage repair momentum is building.

Should I Become a Physician-Employee?
Large healthcare institutions are increasingly purchasing orthopedic practices. What does this mean for patient referrals? How beneficial can it be for orthopedists? The upside is more stability, among other things…and one of the downsides is loss of freedom.

Outrageous Whistleblower Lawsuit Challenged
Spine surgeons sued by whistleblowers in Boston are fighting back. Their lawyer is outraged and says the claimants are just shopping an old and settled case to another judge. Is this the proverbial lipstick on a pig? Find out.

Medical Education Under the Microscope – Is It Up to Today’s Challenges?
Where is the line drawn between what medical schools, residencies, and professors should provide to students and what doctors-in-training should reach for themselves? Here are the results of interviews with three senior surgeons, who opine on things such as attitudes, how people learn, and the possible effects on the field.

The Underlying Meaning of Zimmer’s Purchase of Abbott Spine
From the price paid to the timing, this transaction held an underlying meaning for the entire spinal implant industry. Zimmer, the $4.2 billion (revenue) diversified orthopedic company is now #5 in spine. More to come?

Resurging Lumbar and Cervical Total Disc Replacement Markets! New PearlDiver Estimates
Rumors of the TDA market’s demise were premature. Increasingly positive long term patient data is at the core of a resurging lumbar and cervical TDR market. Senior analyst Matt Menze tackles the TDA market and interviews one of the fathers of TDR, Dr. Scott Blumenthal from the Texas Back Institute. Where is this market actually heading? We think to the $2 billion range by 2015. All details here.

Six Days in June – Biomet and Zimmer Battle for Distributors in Kentucky
Documents filed recently in a Kentucky lawsuit pull the curtain back on an epic battle between Biomet and Zimmer. For six fevered days in June 2007, Biomet CEO Jeff Binder and founder Dane Miller went into the trenches to save one of their own. For all the details, read on.

Multicenter Clinical Trials: Do They Get the Respect They Deserve?
They’re not fast or sexy, but they are critical…large trials, that is. With multiple sites and principal investigators who donate their time, large trials are more complex—and normally yield more actionable data—than smaller, quicker studies. But large trials don’t always get the respect they deserve. And, says at least one physician-researcher, this could affect the future of the field.

Patent Wars: Medtronic Attacks NuVasive
MSD’s lawsuit came amid a period of declining spinal implant market share – from a peak of 60% in late 1998 (just prior to being acquired by Medtronic) to, we estimate, 36% currently – and a growing sense that MSD’s reign as the king of spine was coming to a close. What’s really behind Medtronic’s attack on its former senior exec? Read on.

While the work of neurosurgeons and orthopedic surgeons often overlaps, sometimes the latter parties take the lead on certain approaches.

Explains Dr. Francis Shen, Assistant Professor in the Division of Spine Surgery at the University of Virginia Health System, “Transthoracic and thoracoabdominal approaches to the spine, which allow surgeons access to the front of the vertebrae, have traditionally been performed with the help of either a thoracic or general surgeon. This can be an especially complex approach that involves a number of challenges, including inserting a chest tube, dealing with deflating the lung, potentially taking down the diaphragm, mobilizing the aorta and/or vena cava, and moving the bowel and abdominal structures out of the way. These are not things that spine surgeons tend to be familiar with or comfortable with.”

Giving a historical perspective, Dr. Shen notes, “Several decades ago surgical management for metastatic spine tumors typically involved a laminectomy, which is a straight posterior approach to the spine that attempted to decompress the canal but did not address the tumor. Unfortunately, the results of this were not very good. Then in the ‘70s researchers began to notice that because tumors tended to metastasize to the front of the spine, surgical procedures that addressed the front of the spine tended to do better; as a result surgeons began to go in from the front to remove the tumor. After the tumor was removed you need to reconstruct the spine by putting something else in its place. Frequently, a second procedure is required to provide additional stability to the spine. This second procedure requires turning the patient over and placing additional screws and rods, which can be done the same day or several days later. These are very large surgical procedures with extensive blood loss, and patients may be in the ICU for several days and in the hospital for an additional 7-14 days.”

“More recently,” says Dr. Shen, “surgeons have started using an extracavitary approach where they remove a section of the rib and approach the front of the vertebrae from the back in a slightly oblique direction, which puts them in a plane between the spinal column and the lungs. The power of this surgical approach is that you don’t have to manipulate the spinal cord and you don’t have to enter into the chest cavity. While in theory a posterior approach sounds more comfortable for spine surgeons, it is still a technically demanding procedure. The first few times are just as nerve-wracking as performing any other complex spine surgery.”

Doing their best with limited understanding and equipment, surgeons of the ‘70s and ‘80s used these approaches sparingly. Dr. Shen: “For many years extracavitary approaches were being done only sporadically as the surgical approach was not outlined clearly. Also, the instrumentation was not well developed. It was a limited procedure, as it was primarily in the thoracic spine only, and it was done to drain infections in the front of the spine and remove single-level thoracic herniated discs. It was not used routinely in large tumor reconstructions. Part of the issue was that to reconstruct the spine from an oblique approach, you need a totally different set of instrumentation and implants. In the ‘80s and ‘90s we gained a better understanding of the approach, and by 2000 more of us were seeing the inherent power of this approach. Just in the last few years we have begun developing specialized implants that can reconstruct the front of the spine but be inserted from the back.”

Providing details on the surgery, Dr. Shen explains, “We have made great strides. We have now moved from the thoracic spine to performing this in the lumbar spine as well. And now while working in the lumbar spine, we can spare the nerve roots. The nerve roots in the thoracic spine are typically not a problem because they are mostly sensory nerves that can be resected if needed. This allows you more room for placement of the instrumentation and for performing the decompression. But in the lumbar spine, if you cut and tie off a nerve root you run a substantial risk of not just ending up with a sensory problem but muscle weakness as well. The newer implants that have been developed can be expanded. In these cases, you must place the reconstructive cage in at an angle past the nerves in a collapsed position and then flip it upright into place. Once past the nerves, the reconstructive cage can be expanded inside the body. The capability to perform this procedure routinely in the lumbar spine didn’t exist until the last few years. Despite all of the advantages gained from these expanding cages, there are still limitations and I am proud to be part of a team working with industry to develop the next generation of these implants.”

There are significant advantages to an extracavitary approach, says Dr. Shen. “Because this is a single-stage procedure, you don’t have to perform both a front and back surgery. And once the technique is mastered, the flexibility inherent in an extracavitary approach allows the experienced surgeon to use it for a number of spinal disorders in addition to tumor surgery, including thoracic and lumbar degenerative disc problems, infections, trauma, and deformity correction. Its elegance comes from the fact that after you are done, you have decompressed and reconstructed the front and back of the spine, without having to enter into the chest or abdominal cavity. There is no need for chest tubes and postoperative bracing, and typically you don’t have as many postoperative bowel or great vessel issues.”

But the user friendliness ends there. Dr. Shen: “The biggest issue is that spine surgeons tend to shy away from the approach as there is quite an initial learning curve. When you first learn to decompress and evacuate a tumor it is challenging to work around the spinal cord and nerve roots, because there is not the same visibility as from the front of the spine. If you are coming in from the left, then the right side can be hard to access. In my practice, if I need to I will perform bilateral extracavitary approaches and open up the opposite side quickly to circumferentially decompress the spinal column. Making this simpler is the curved instruments with which we can evacuate the tumor, and an operating table that can be rotated from side to side. But there is always the concern about the spinal cord and corresponding nerves. In placing these instruments you have to sneak them in between the spinal cord and nerves and risk stretching the nerves or causing a spinal cord injury.”

“Then there is the time factor,” says Dr. Shen. “The first few times that you do this procedure time on the table can be substantial, and even after doing a few dozen it can still be a lengthy undertaking. And the blood loss can still be extensive.”

Dr. Shen, who is well versed in the approach, is pushing it to the next level. “I have begun using this approach with post-traumatic injuries and acute fractures; in selected cases I am now moving towards addressing patients with spinal deformities as well. If there is a long curve that requires several anterior releases you may need to address many levels, and a posterior approach is not best. If, however, you can identify one kyphotic or scoliotic segment that is centered at one level, then performing an extracavitary approach may be ideal.”

So how to open this complex procedure to more spine surgeons? “I get a lot of questions from both orthopedic and neurosurgical surgeons, so that tells me there is still a lot of apprehension about this approach. I’ve received a number of calls and emails from people interested in knowing the finer points of the procedure. My wish is that spine fellowships, spine societies, and spinal implant companies will help provide additional training. And I am hopeful that as more people report on their experience with this approach, more surgeons will start to investigate it. I’ve tried to spread the word by presenting this topic and my experience at meetings of the North American Spine Society, the International Society of the Lumbar Spine, and the American Academy of Orthopaedic Surgeons. As we move forward and get longer follow-up data, I will continue to report on our experiences and hopefully encourage others to learn more.”

Dr. Shen’s final thoughts? “While an extracavitary approach is not necessarily the right choice for every patient, it is in the armamentarium of options all spine surgeons should at least be aware of. If someone is not comfortable performing the procedure, there is always the option of referring the patient to someone who does it regularly.”