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Welcome to the home of BalancedBack®, the innovative new total joint replacement solution.
We hope you’ll read through the following information carefully, then use it to start a discussion
with your doctor about what you can realistically expect after fusion, and if BalancedBack®
might be right for you. If you or your doctor have additional questions about the procedure,
we encourage you to schedule a call with a member of our clinical team.
If you’re suffering from back and/or leg pain that prevents you from enjoying life, you may have been told that fusion or artificial disc replacement (ADR) is the only option for relief. Today, you have another option: BalancedBack® Total Lumbar Arthroplasty. BalancedBack® is the latest innovation in artificial disc technology—the first “total” joint for the lumbar spine. It represents a major advancement in how back/leg pain is treated, and follows closely in the footsteps of other total joint replacements, such as hip or knee total arthroplasty.
The BalancedBack® procedure addresses the same pathologies as fusion, but with one important difference: It replaces the function of the affected spinal joint with a motion device, preserving range of motion and protecting adjacent levels.
The device is made up of two sides, each of which has a top and bottom component that are fixed to the bone. The bottom component also has a “tail,” allowing your surgeon to correct your posture while implanting the construct a neutral position. A screw keeps each side in place while your bone heals into the implant, and a small clip (shown in green) prevents the screw from working its way out as you move back and forth.
The unique design of BalancedBack® means that it replaces the function of both the facets and the disc (unlike both anterior disc replacement which address the disc only). BalancedBack® is implanted from a posterior approach instead of through the belly, allowing your surgeon to directly decompress pinched nerves while restoring biomechanical stability to your spine.
In the sections below, we outline in greater depth how the device works, what makes it different from fusion and ADR, and the benefits patients gain from Total Lumbar Arthroplasty.
Table Of Contents
Spinal stenosis—the narrowing of the passages of the spinal cord and nerves—is one of the primary contributors to leg and back pain. If you suffer from stenosis, you’ve probably already done enough research to know that the most effective way to relieve the leg pain is to decompress pinched nerves. You may also be familiar with other relevant technologies—like anterior disc replacements (TDRs) for discogenic back pain, or interspinous spacers for temporary relief of leg pain—and may have even considered combining these technologies in a front/back or “360” procedure as a potential solution.
To understand how BalancedBack® technology works, let’s start with the basics.
Each level of your spine is mobile, allowing for bends, twists, and compound motions. You need to rotate your neck, for example, to look over your shoulder when driving. Motion keeps joints healthy, and is even thought to play a role in cell signaling and nutrition of tissues. Most of us know intuitively that stopping motion is not a good thing. But did you know that the most important reason you need motion is to adapt your posture throughout your day? Imagine trying to sit comfortably on a couch with your back fused in a position for standing, or vice versa—trying to stand with your back fused in a seated position.
Motion is the key to maintaining spinal balance, or “sagittal” balance, which refers to the overall effect of the various curves of the spine. Let’s focus on the lumbar “lordotic” curve of the low back: As you age, your lumbar region naturally flattens out, which can lead to a pitched-forward posture when standing. To compensate for carrying the center of your mass too far forward, postural muscles work overtime, and you may even bend your hips and knees to find balance in what is called “compensatory flexion.” Surgeons correct loss of lordosis or “flat back” by adding lordosis to the spine. To do that, they perform fusion, removing a joint, to bring patients back into balance—standing balance, that is.
This set of illustrations shows the progression of loss of lordosis: On the far left is a normal standing posture, which can changes to the second position as you age. This position is hard to sustain and often leads to the third, painful position as a way to compensate, with legs bent and hips flexed to relieve the low back muscles. In an effort to recreate a balanced posture, surgeons remove the portion of bone shown in red in the fourth illustration, and fuse the segments together into one mass.
But people don’t just stand. We sit, slump, lay on the couch, ride in a car, stand back up, push a shopping cart, etc. The amount of lordosis you have in your lower back should naturally change all day long, as you switch between a standing position, a sitting position, and a slumped position. When you’re standing upright, you have more of a curve in your spine than when you’re sitting. And when you’re sitting in a slumped position (like when you’re watching TV on the couch), you lose an even greater degree of curvature. So while these “lordotic” fusions may provide the right curve for standing, that curve is unnatural for sitting and slouching, causing pain and major degeneration of the spine and even the hip joints.
These illustrations show a normal standing position first, then a fused standing position with several segments of the spine fused into one mass.. While that position works for standing, it doesn’t work as well for sitting, as shown in the third illustration, and in a more extreme slumped posture in the fourth illustration.
One of the best ways to understand the mechanical problem created by a single fusion posture was illustrated by Patwardhan et al. at the 2017 International Society for the Advancement of Spine Surgery. The researches scanned patients before and after fusions, and traced the outline of their bones in different postures as shown in the figure below. In the first row of pictures below, the orange trace shows the spine slumped in front of a computer, the yellow shows sitting posture, and the blue shows your spine standing.
Now for the interesting part: the second row of pictures shows two traced lines. The orange shows the actual posture compared to where the spine “wants” to be mechanically, shown in blue. Because of how dramatically different the fused standing position is compared to sitting and slumped sitting, the spine experiences tremendous stress in the areas adjacent to the fusion.
So what can happen as a result of that stress? There are a number of terms for the breakdown in levels adjacent to a spinal fusion, including fusion disease, adjacent segment disease, and proximal junctional kyphosis. Needless to say, outcomes from these cases are terrible. Consider the series of x-rays shown in the figure below:
These X-rays show successive revisions where a patient is treated with fusion, the biomechanics is altered, the fusion breaks down and is extended further altering the spinal mechanics, and the process repeats with more revision surgeries and more screws.
BalancedBack® stops the downward spiral of the fusion cycle. How? The BalancedBack® implant allows your surgeon to stabilize and adjust your degenerated spine like a fusion, but without altering your spinal mechanics. BalancedBack® allows you to naturally flex and extend your spine dynamically, adjust posture throughout the day, and limit stress transmitted to the adjacent levels.
The x-rays below shows a BalancedBack® patient standing and sitting. In this case, he unwinds (or flattens out) 12 degrees of lumbar lordosis between these two postures, and also dramatically tilts or retroverts his pelvis to comfortably adjusting his hips, shown by the blue dotted line. (Many patients with back pain and sitting intolerance after fusion surgery are actually experiencing hip pain - fusion can accelerate degeneration in those joints as well.)
These images show a BalancedBack® patient comfortably standing (left) and sitting (right), naturally adjusting posture without subjecting the spine or hips to the hyper-physiologic stresses experienced after fusion.
The series of x-rays below shows another BalancedBack® patient, who was previously advised that he needed a multi-level fusion from T10 to the pelvis to relieve his severe stenosis and correct his posture. Instead, he chose BalancedBack® Total Lumbar Arthroplasty with excellent results. The first x-ray shows this patient before surgery, pitched forward 9 cm. In the middle x-ray he is standing perfectly straight after only two levels of BalancedBack® implants (vs. the planned 8 levels of fusion). And on the right he can comfortably flatten his back and properly tilt his pelvis to sit in a chair.
Earlier we talked about the complex motions of the spine—like looking over your shoulder to check the blind spot while driving. And if you’ve been researching other technologies for your back pain you may have noticed that some talk about three-dimensional motion.
In reality, though, the low lumbar spine doesn’t move that way. In your lower back, almost all of the motion comes from L4/L5 and L5/S1, which are buried deep in the pelvis and constrained by the iliolumbar ligaments and other structures. These levels don’t have complex motion like the neck—their main job is to flex and extend, not twist and rotate. Theses levels cooperate with the hips, knees, ankles, and levels above to adjust posture.
To do this, two BalancedBack® implants are carefully placed along the neutral or “follower load” axis of the spine, using a posterior approach. This position allows you to minimize muscle recruitment while you dynamically adjust your posture in any position.
The two balls of your hip joints define a flexion axis, shown here in red. The two sides of a BalancedBack® construct also define a flexion axis, shown in blue, that works in harmony with the red hip axis.
It’s pretty simple, really: Each side (left and right) has a top and bottom articulating component, fixed to the bone with porous bone ingrowth surfaces just like a hip or knee replacement. The bottom component also has a “tail,” allowing your surgeon to correct your posture and implant the construct in a neutral position along the length of the pedicle, like a fusion construct. A screw keeps each side in place while your bone heals into the implant, providing initial stability. The clip prevents the screw from working its way out as you move back and forth—after all, BalancedBack® moves with you!
Posterior view of one side of the BalancedBack® construct (left), sagittal view (center), and oblique view (right).
BalancedBack® implant shown in an actual patient pre-operative plan. Notice the position of the implants over the pedicles and the center of rotation (COR) of the device.
The BalancedBack® implant uses the same fixation anatomy as the typical pedicle screw constructs used in fusion surgery. The illustrations below show on the difference in BalancedBack® vs. fusion, with a screw construct on the left, BalancedBack®on the right, and both superimposed in the center.
If you look closely at the superimposed pictures in the center, you will see that the BalancedBack® tails are entirely within the bone, and do not protrude in the back the way pedicle screw heads do. This is important because you have muscles in this same space. The dramatic difference in postoperative back pain between BalancedBack® patients and fusion patients is partly due to the simple fact that BalancedBack® hardware is not rubbing against the muscles. In other words, pedicle screws can hurt!
The left image shows two fusion pedicle screws placed through the pedicle into the vertebral body. The image on the right shows the BalancedBack® implant. The center image shows the two outside images superimposed, to illustrate how far the pedicle screws protrude into the space occupied by postural muscles.
Fusion aside, you may still be wondering about some other technologies and techniques you’ve read about. Some patients are told they should proceed with an ADR, and if that doesn’t address the pain associated with your stenosis, they can get a second surgery to insert an interspinous spacer. This may sound like a reasonable option, but in reality, this creates a mechanically impossible situation.
It’s important to understand that ADR and interspinous spacers are different technologies with different biomechanics that were never intended to be used together. Consider the illustration below. On the left you can see how an interspinous spacer works—by propping the spinal segments open. Interspinous spacers were never intended to be motion technologies; they were meant to temporarily prop open the foramen and temporarily relieve stenosisto buy you some time.
The center image shows an anterior disc. Discs are not meant to address stenosis, they’re meant to replace a disc only. As you’ve already learned, replacing a disc will not relieve stenosis.
So putting these two devices together, as shown in the right image in the illustration below, actually creates a construct that doesn’t move. While this may provide an outcome similar to a fusion (or as some would suggest, a “soft fusion”), this is not a motion construct.
You might still be asking, why not place an anterior disc through the belly and then make a second incision to decompress the back for stenosis? Well, you can’t use an anterior disc by itself, because most discs rotate freely. These products were designed to work with the facet joints. When you remove the facets as part of the decompression for stenosis, the disc can’t resist rotation and shear like BalancedBack®. ADRs simply aren’t designed to work this way. BalancedBack®, on the other hand, can be used in most cases where a surgeon would typically do a fusion, restabilizing the decompressed spine and re-establishing normal kinematics. And again, this is all done from the back, in one approach.
Seem simple? Many good ideas are. BalancedBack® is the result of 15 years and almost $20 million dollars of research, resulting in 45 issued patents around the world.
BalancedBack® is specifically designed to replace the function of the facet joints and the disc. It is the only product that allows your surgeon to do a full decompression from the back while also preserving motion.
So what’s causing your pain? BalancedBack® can address the most common causes of back and leg pain. BalancedBack® also allows for postural correction, stenosis decompression, removal of arthritic facets, and relief of other factors causing muscle irritation and spasm. BalancedBack® is the only implant of its kind.
For more information on any of the topics covered in this article, we welcome you or your doctor to schedule a call with a member of our team. Or feel free to submit a question to get a conversation started. We’re here to help!