William J. Sonstein, MD, FACS, Senior Partner at Neurological Surgery, P.C., Introduces Ultrasonic Spine Institute for Safer, More Effective Revision Spine Surgery

By: Michael Ferguson
Thursday, February 5, 2015
Specialty: 

Leading-edge ultrasonic technology enhances treatments for failed back syndrome.

When back pain recurs after an initial curative operation there is sometimes the need for a revision procedure. Often, spinal instability is the exacerbating factor, and if it continues, it will lead to disc reherniations or iatrogenic bone or vertebra slippage, which cause spinal stenosis.

Typically, conservative strategies, such as physical therapy or epidural injections, effectively manage painful symptoms. However, when such treatment fails and MRI imaging reveals that structural problems likely cause the pain despite a previous operation, revision surgery is indicated.

William J. Sonstein, MD, FACS, Senior Partner at Neurological Surgery P.C. (NSPC), Chief of Neurosurgery at North Shore-LIJ Plainview Hospital, collaborates with the rest of NSPC’s team of 15 neurological spine surgeons, as well as orthopedic surgeons, to provide a wide array of surgical options for revision spine surgery: posterior lumbar interbody fusion, kyphoplasty and X-STOP interspinous spacers. He also uses minimally invasive approaches that reduce blood loss, complication risk and recovery time. For all procedures, Dr. Sonstein uses two state-of-the-art technologies that enhance the efficacy and safety of revision procedures.

Advancing Spinal Surgery

NSPC-Sonstein Studies Scans 250
Dr. Sonstein analyzes a lumbar MRI scan.

Dr. Sonstein selects his tools for spine surgery with an eye to progress and a focus on patient outcomes. The two devices he has recently incorporated are among the field’s most game-changing developments in decades and will feature prominently in the Ultrasonic Spine Institute, which will be an NSPC Center of Excellence.

“There aren’t many devices that have improved spinal surgery outcomes with their introduction,” he says. “The basic tools we use haven’t changed dramatically in the last 25 years. But the Medtronic Aquamantys System and Misonix Ultrasonic Surgical Aspiration System have revolutionized some of the things I do. They address two of the major complications commonly associated with revision spine surgery — blood loss and spinal fluid leakage. I use these devices for nearly every spine surgery I perform.”

NSPC-Misonix Sona Star 750
The Misonix SonaStar Ultrasonic Aspiration System effectively emulsifies or “melts” bone during laminectomy or discectomy for stenosis. This preserves soft tissue such as spinal membrane, reducing the possibility of complications, such as spinal fluid leakage.

The Aquamantys System uses transcollation technology to hemostatically seal soft tissue and bone, which reduces blood loss and transfusion rates and saves operative time. Transcollation — the transmission of radiofrequency energy to cauterize blood vessels in tandem with continuous application of saline to the vessels’ surface — quickly shrinks veins, which prevents excessive burning and achieves optimal hemostasis. Previous electrocautery devices didn’t allow wide coverage areas, which extended procedural time.

NSPC-Medtronic Aquamantys 750
The Medtronic Aquamantys System utilizes Transcollation technology that combines radiofrequency energy and saline to stop bleeding quickly by shrinking blood vessels. This helps minimize blood loss and reduce transfusion rates during spine surgery.

“The Aquamantys covers a wide surface area, so you’re able to shrink many blood vessels to allow faster and more efficient surgeries that reduce blood loss,” Dr. Sonstein says.

The Aquamantys System is used in a number of additional spine surgeries, including anterior lumbar interbody fusion, decompression, discectomy, laminectomy, transforaminal lumbar interbody fusion (TLIF), posterior cervical laminectomy and fusion, posterior lumbar interbody fusion (PLIF), scoliosis surgery, and minimally invasive TLIF.

Better Bone Emulsification

When surgeons resect bone around critical structures, such as the spinal cord and the nerve bundles located within the spinal column, their sharp tools can cause serious complications if even the slightest targeting discrepancies arise. Biting instruments and high-speed drills have sharp edges that can tear proximal soft tissue and critical nerve bundles. Dr. Sonstein uses ultrasonic emulsification equipment for precise maneuvering that spares soft tissues, reduces bleeding and preserves bone.

Ultrasonic devices feature blunt metal tips that rapidly vibrate in two directions. Because there are no sharp surfaces on the tips, ultrasonic emulsification devices allow Dr. Sonstein the capability to navigate small spaces in the spinal canal without having to protect critical structures from catching on the tip of a serrated edge.

“Ultrasonic devices address the bone, not the soft tissue,” Dr. Sonstein says. “This allows me to decompress the nerves by going over them without having to worry about affecting the nerve or soft tissue. In many revision procedures, we encounter significant amounts of scar tissue, which attaches to neural tissue. This makes approaching the compressed nerve challenging and can lead to tears during the decompressions and dissections required to access the surgical site. These are common complications, occurring in approximately 10 to 20 percent of revision procedures, but ultrasonic bone emulsification devices greatly reduce the risk of such complications.”

Hand tools and high-speed drills remain important components for spine surgery, but treating with the instruments requires sculpting bone around nerves to prevent leaving sharp edges that might puncture a nerve membrane and cause a spinal fluid leak. Ultrasonic emulsification devices facilitate bone sculpting, significantly enhance surgical precision and support postsurgical recovery by reducing the chance for soft tissue injuries that can cause postoperative pain and prolong the rehabilitation process.

Restoring Vertebral Height

According to the American Association of Neurological Surgeons (AANS), approximately 10 million Americans have osteoporosis, and 34 million more have low bone mass, which puts them at higher risk for vertebral compression fractures, which are the most common fracture in this patient population.

Surgically treating elderly patients has traditionally been challenging, so back surgery has often not been an ideal course of treatment. To surgeons on the front lines, finding an effective, minimally invasive solution to correct these injuries was of paramount importance.

Kyphoplasty is a minimally invasive solution to treat spinal compression fractures caused by osteoporosis, metastases and multiple myelomas, vertebral hemangiomas and vertebral osteonecrosis. It is also used to support weak vertebral bodies before surgical stabilization.

“This is another procedure that revolutionized spine surgery when it came out,” Dr. Sonstein says. “Before, bracing was the only mechanism for treating spinal compression fractures suffered by people who were typically elderly or who had osteoporosis. Fractures cause these patients to become immobile, which worsens osteoporosis and leads to secondary effects from the fracture, such as gastrointestinal problems because of the resulting deformity. It’s a vicious cycle that kyphoplasty can end, and those of us who have been performing it since its development years ago offer incredible precision.”

Kyphoplasty is a percutaneous procedure that applies functional principles of angioplasty to correct vertebral height following a compression fracture. Using X-ray guidance, Dr. Sonstein introduces a hollow needle into the fractured vertebra. He threads a surgical balloon through the needle and inflates it, creating a cavity and restoring the vertebra to its natural height and shape. He then injects cement into the space for structural reinforcement.

Kyphoplasty improves upon vertebroplasty — another treatment for compression fractures that consists of injecting cement directly into the fractured bone through a hollow needle.

“This is a safer procedure than vertebroplasty because you have more control over the application of the cement,” Dr. Sonstein says. “In vertebroplasty, surgeons had to be very careful to apply it in manners that prevented leakage, but kyphoplasty offers a more controlled application of the cement, which significantly reduces the risk of complications.”

Complication rates for kyphoplasty performed to correct vertebral compression fractures are less than 2 percent, according to an AANS estimate.

Give the Lumbar Spine Some Space

NSPC-Sonstein Patient Exam 250
Dr. Sonstein examines a patient who may require surgery on her neck.

Lumbar spinal stenosis also commonly affects the elderly population, causing severe back and leg pain due to narrowing of the spinal canal. Traditionally, neurosurgeons corrected the condition by performing a laminectomy to expand the spinal canal. Dr. Sonstein provides a less invasive treatment to free nerves from an impinging spinal cord and relieve leg pain and cramping secondary to lumbar spinal stenosis.

Laminectomy requires removal of the posterior aspect of the affected vertebrae to expose the spinal canal and reduce pressure on the nerves or spinal cord. Following the procedure, patients can only perform limited activities for several weeks and often participate in physical rehabilitation regimens as part of the recovery process.

The X-STOP Interspinous Process Decompression System is a titanium implant placed between the lumbar spine’s posterior spinous processes. Through a minimally invasive procedure, Dr. Sonstein places the X-STOP in one or two levels of the affected vertebrae.

“This procedure means patients go through less surgery, and it results in virtually no complications because you don’t have to enter the spinal canal,” Dr. Sonstein says. “It’s an easy procedure and the device takes little time to place, so it’s excellent for elderly patients. It translates to less trauma for the same results as a laminectomy.”

“I provide a number of options to treat spinal disorders — particularly degenerative spine disorders and failed back surgeries — that promote optimal outcomes. When frontline, conservative treatments fail, I implement a complete armamentarium of tools to correct spine problems in the safest and most effective manner possible, with reduced blood loss and surgery time.”
— William J. Sonstein, MD, FACS, Senior Partner at Neurological Surgery, P.C., Chief of Neurosurgery at North Shore-LIJ Plainview Hospital

Dr. Sonstein underscores the fact that the procedure addresses the physiological condition that makes stenotic symptoms unbearable for most people.

“The X-STOP distracts and causes a slight flexion in the spine,” he says. “Stenosis causes pain when people walk and improves when they sit. This is because they flex their spine when they sit and extend themselves when they walk. The X-STOP relieves pain by providing flexion.”

Patients who have moderately impaired function and have exhibited relief during flexion are indicated for treatment with X-STOP after completing a six-month regimen of conservative treatment.

Fusing Failed Backs

Patients who suffer from ongoing back pain may require surgery to repair spinal instability by fusing vertebrae into a single bone. A number of conditions, including degenerative disc disease, infection, spinal fracture, spinal stenosis, scoliosis, spondylolisthesis or a tumor, can cause symptoms that spinal fusion can correct. Dr. Sonstein confirms the underlying cause of back pain with MRI or CT scans.

NSPC-Fusion Instrumentation 750
Instrumentation used to perform posterior lumbar fusion

Dr. Sonstein performs a posterior lumbar interbody fusion (PLIF) to induce the body’s biologic response to heal broken bones. The PLIF procedure promotes bone growth between unstable vertebrae, which reinforces the spinal structure and limits the motion at that segment.

PLIF surgery requires Dr. Sonstein to remove the lamina of the unstable vertebrae and retract the nerves within the bone. He shaves the cartilage and forms an open space within the vertebra, in which he places a spacer made up of bone, a cage or an artificial plastic device filled with bone material to foster bone growth around the segment.

“Spacing devices provide better fusion between two bones because I can fuse more of the spinal surface,” Dr. Sonstein says. “To get the spacers in, a good amount of the joint has to be removed, which means the spine has been destabilized. We augment that with pedicle screws, which go through the bridge between the front and back of the spine, and connect the screws with rods.”

Patients spend several days in the hospital, and although full spinal recovery can take months, patients often feel less pain before the bones fully heal.

Operating in Concert

NSPC-Sonstein In Surgery 250sq
Dr. Sonstein performs a laminectomy in the OR.

Dr. Sonstein performs revision procedures in tandem with an orthopedic surgeon. The different but overlapping training each specialist brings to the operating table enhances surgical efficacy.

“You need two people to operate on the spine,” Dr. Sonstein says. “It’s important to collaborate with an orthopedic spine surgeon for these procedures because there are two sides to the spine. Operating with a good assistant who understands how to retract without damaging nerves and allows safe decompression to prevent spinal fluid leaks is critical to optimal outcomes. When you’ve been working together for a long time, you learn to anticipate each other’s maneuvers, so it’s much safer for the patient.”

Each surgeon assists to perform certain maneuvers required by different procedures. For example, in a PLIF operation, surgeons operate on either side of the spine, placing screws simultaneously for more efficient and safer surgeries that reduce anesthesia time, reduce blood loss and promote optimal outcomes.

Reading between the Revision Rates

Surgical revision for failed back syndrome can result from unresolved pain following the initial surgery, device failures or surgical complications. William J. Sonstein, MD, FACS, Senior Partner at Neurological Surgery, P.C., Chief of Neurosurgery at North Shore-LIJ Plainview Hospital, notes that when he meets patients who have undergone previous surgeries but found no relief, “they are miserable because of persistent pain or weakness” and are often willing to consider another operation.

A study in the journal Spine found that approximately 19 percent of patients who underwent spine surgery required revision within 11 years. Of these, most needed the additional procedure to treat the same cause of pain symptoms prompting the original surgery. Studies in Acta Neurochirurgica and Spine show that success rates for revision surgeries stand between 30 and 35 percent nationwide.

To achieve greater success rates, Dr. Sonstein carefully selects patients for his revision procedures based on personal factors, results of conservative treatments, diagnostic imaging and clinical examination. He also collaborates with an orthopedic surgeon to ensure the neurological and musculoskeletal systems involved are thoroughly examined at each stage of the operation.

For more information about revision spine surgery at NSPC, visit nspc.com.