Minimally invasive spinal surgery

April 29, 2016

For patients with focal spinal degeneration, surgery is an intimidating prospect. Significant pain and blood loss, as well as hospitalization for three to four days, are typical. Yet forgoing surgery can mean living with pain and possibly disability.

All three campuses of Mayo Clinic offer minimally invasive spinal surgery, which generally entails less pain and blood loss, a shorter hospital stay, and outcomes comparable to open surgery. "Minimally invasive spinal procedures allow us to do very large surgeries a little less disruptively," says Mohamad Bydon, M.D., a consultant in Neurosurgery at Mayo Clinic in Rochester, Minnesota.

"Misalignment of the spine at one or two levels, spinal stenosis or instability at a few levels, and herniated disks can definitely be treated through a minimally invasive approach. It is a great option for patients," adds Selby G. Chen, M.D., a consultant in Neurosurgery at Mayo Clinic in Jacksonville, Florida.

Minimal muscle dissection

Open spinal surgery typically involves a large midline incision, dissection of muscle tissue off the midline bony structures, and retraction of those muscles for long periods of time as the surgeon proceeds with decompression or fusion. "After a surgeon cuts through all that tissue, patients wake up with a lot of muscle spasms and severe back pain. It's not a pleasant experience," says Chandan Krishna, M.D., a consultant in Neurosurgery at Mayo Clinic in Phoenix/Scottsdale, Arizona.

Minimally invasive spinal surgery is performed through a smaller incision. "We do a more focal dissection through the muscle to reach the pathology," Dr. Bydon says. "Pedicle screws or any other hardware can be inserted through a tubular retractor or through percutaneous procedures."

Often an oblique approach is used, which avoids the iliopsoas and its many nerves. Blood loss is also minimized — usually less than 100 cubic centimeters (cc), compared with 300 to 500 cc with an open procedure. Patients frequently return home one day after surgery.

An essential component of minimally invasive spinal surgery is intraoperative imaging to guide the procedure. "Real-time imaging allows us to place the screws accurately without having to dissect all that muscle tissue off the bone," Dr. Krishna says.

At Mayo Clinic, neuronavigation technology minimizes patients' exposure to radiation. Only a single, low-radiation 3-D X-ray is taken before minimally invasive spinal surgery.

The benefits of minimally invasive spinal surgery can make it an attractive option for most patients, but especially helpful for those who are older or have comorbidities.

"If you're concerned about minimizing a patient's time under anesthesia in the operating room, or have a patient with significant myofascial pain and it's important to limit the amount of muscle disruption, then minimally invasive spinal surgery is often an excellent option," Dr. Chen says.

Dr. Bydon also notes the advantages of what he calls "mini open techniques," such as using cortical screws rather than pedicle screws, to repair multisegment lumbar stenosis in elderly patients. "With cortical screws, we don't have to dissect as much muscle tissue as we do with pedicle screws during an open procedure," he says.

Back to jumping from planes

For many patients, minimally invasive spinal surgery can resolve disabling problems and facilitate a return to normal activities. Dr. Krishna cites the case of a 39-year-old patient — a U.S. military contractor who trains special forces members to jump out of airplanes.

"He had a back injury that caused severe low back pain with a shooting element," Dr. Krishna says. After living with the pain for a few years, the patient consulted Dr. Krishna, who initially recommended conservative management. When that treatment wasn't effective, Dr. Krishna suggested minimally invasive spinal fusion surgery.

"We finished the surgery in the early afternoon, and he went home the next morning," Dr. Krishna says. "His pain has resolved, and he is living an active life. He will be doing a desk job for four to six months, but after that he should be back to jumping out of airplanes."