Frequently Asked Questions

The anterior spine space includes the tissues, structures, organs, and blood vessels, along with the vertebral bodies and intervertebral discs, which lie in front of, or anterior to, the spinal cord and nerve roots exiting the spinal cord. This space can be entered and critical structures can be moved out of the way to provide a corridor, or route of access to the anterior spine including bone and the spongy discs in between.

The anterior spine space can be difficult to access and requires that critical structures including the abdominal wall muscles, the peritoneum (which lines the abdomen and protects the internal organs including small and large intestine), the ureter, along with major blood vessels including iliac arteries and veins all be moved out of the way and stay protected during the spine part of the procedure. This anterior spinal exposure typically requires a spinal access surgeon, working together with a spine surgeon as a team.

Spinal access surgeons are experienced in anterior spine exposure and often have received dedicated training in advanced exposure techniques. In addition, these surgical specialists often have formal training as a cardiothoracic, vascular, or general surgeon, although their practice may predominately focus on spinal access. It is important that your spinal access surgeon be highly experienced in anterior spinal exposure and perform these procedures regularly, in order to maintain this very specialized skill set. This is critical to the success of the procedure and in minimizing risk and complications.

The question of ‘why do back (spine) surgery from the front’ is a common one and can be quite confusing. Viewing a model of the spine can help to better explain the role of the anterior spine in major spine procedures, including fusions, disc replacements, and removal of vertebral bodies (corpectomy). Simply put, the bones (vertebral bodies) and spongy shock absorbing discs (intervertebral discs) both lie in front of the spinal cord. Many spine conditions originate, in some way shape or form, from disc degeneration, or breakdown. The most direct route of access to the discs is actually from the front. While spinal fusion procedures can be entirely performed from the back, more of the disc can be removed and larger spacers (with higher fusion rates) can be placed from the front. Also, it is possible, in select patients, to replace the disc all together with a synthetic disc. This lumbar total disc arthroplasty can only be accomplished by working on the anterior spine. The other distinct advantage of anterior spine surgery is potentially eliminating the need to cut through the back muscles next to the spine. When spine surgery is performed from the back only, traditional techniques involve separating, and potentially devitalizing, the muscle from the spine. This is necessary to expose the spine, but may have a destabilizing effect on the spine and impact on the development of further spine disease. You should discuss further with your spine surgeon to see if you are a candidate for anterior spine surgery.

The side, or lateral aspect, of the intervertebral discs can also be exposed for certain spine fusion procedures, typically when the spine pathology primarily involves degenerative disc disease (DDD). These procedures are performed with the patient laying on their side during surgery, termed the ‘lateral position’. The extreme lateral interbody fusion (XLIF™) and oblique lumbar interbody fusion (OLIF™) were designed to take advantage of the lateral disc space because it is remote from the major blood vessels which lie directly on the spine. This decreases the risk of major vascular injury during both exposure and spine fusion. Also, because this area of the disc is remote from blood vessels, even smaller incisions (< 1 inch) can be used, making these techniques truly minimally invasive. Specialized dilating systems, retractors, and instruments make this minimally invasive approach to spinal fusion possible.

Muscle sparing techniques allow for minimal trauma to abdominal wall muscles. By separating the muscle instead of cutting it, the muscle is fully intact and functional after surgery, to aid in recovery while the back heals.

A retroperitoneal approach means that the abdominal cavity is not violated, allowing the peritoneum to remain intact and act as a biologic barrier to protect the internal organs such as the intestinal tract. This eliminates the risk of scar tissue forming inside the abdomen, which could result in bowel blockage in the future. It also dramatically reduces the risk of injury to intra-abdominal organs, as they are not directly encountered during the procedure.

Conservative treatment is typically the first line of therapy. This may include physical therapy, core muscle strengthening, and sometimes pain medications and steroid injections. However, spine surgery may become a treatment option if these measures fail to alleviate symptoms. Your spine surgeon will explain in detail the nature of your spine pathology along with the indications for anterior spinal surgery.

Degenerative disc disease is a bit of a misnomer, as it is not necessarily a disease as much as it is the natural process of degeneration and breakdown that the intervertebral disc experiences over the course of life. At birth, the intervertebral discs are full of water and spongy, acting as shock absorbers and allowing for range of motion in the spine. The combination of time and wear and tear on the disc can lead to deterioration, or degeneration, of the disc. Degenerative disc disease often manifests as back pain; however, the disc can also rupture and irritate nerves or bulge and narrow the spinal canal.

The XLIF™ and OLIF™ procedures are truly minimally invasive spine procedures. Both procedures utilize very small incisions (< 1 inch) and advanced technology to access the spine and achieve excellent fusion results while offsetting some of the risks of traditional open anterior spine surgery, most importantly major vascular injury. The fundamental difference between the procedures is dependent on the trajectory of approach to the disc itself as well as the disruption of the psoas muscle. The XLIF™ procedure violates the psoas muscle as the trajectory is perpendicular to the spine. The OLIF™ procedure approaches the lateral spine at an oblique angle, as the name implies. This allows for exposure of the disc without violating the psoas muscle. By avoiding disruption of the muscle, major nerves, which run in the muscle and supply motor and sensory fibers to the legs, are protected by the psoas muscle. This essentially eliminates the risk of nerve injury while still being a minimally invasive spine procedure, with all the associated benefits of that technique.

There are many conditions of the spine, both congenital, and acquired, that can result in instability, pain, or deformity. While the spine problems that may ultimately benefit from surgical treatment is quite long, they all fall into one of these three categories.

A history of prior abdominal surgery is not necessarily a contraindication for anterior lumbar spine surgery. In fact, with proper pre-operative planning and coordinated care between an expert spinal access surgeon and your spine surgeon, the vast majority of patients who have undergone abdominal surgery are still candidates for an anterior spinal procedure. There are relatively few absolute contraindications to anterior spine exposure. At RMASA, we review each patient individually, including a thorough history and physical exam along with a detailed imaging review, in order to provide a detailed surgical plan taking into account any risk factors including prior abdominal surgery.

There are multiple types of abdominal wall hernias along with techniques for repair, including the placement of mesh via an open or laparoscopic approach. With the exception of laparoscopic inguinal hernia repairs, most open and laparoscopic ventral hernia repairs do not impact on anterior spine exposure at all. Rarely, the mesh that was placed for hernia repair is encountered during spine exposure, but is easily moved out of the way. Laparoscopic inguinal hernia repairs represent a challenge in terms of anterior spinal access surgery, because the retroperitoneal space, which is accessed for spine exposure, has already been used to place mesh and repair the hernia. While this increases the level of technical complexity, it does not prohibit re-entry into the retroperitoneal space in skilled hands.

‘Absolute contraindications’ is a relative term in and of itself. As spinal access surgery has evolved into a highly subspecialized practice, and techniques have evolved to include the lateral spine space, many contraindications to anterior spinal surgery have become obsolete. That being said, 3 major categories of prior abdominal surgery still exist that may prohibit anterior retroperitoneal lumbar spine exposure. ‘Radical’ pelvic surgical procedures, most commonly hysterectomies, prostatectomies, and colectomies, can render the retroperitoneal space very hostile. Typically, a radical procedure involves dissection and removal of lymph nodes which surround the large blood vessels directly adjacent to the spine. This creates severe scarring in and around the very blood vessels that must be dissected and preserved during spine exposure. Like ‘radical’ pelvic surgeries, extensive retroperitoneal lymph node dissections (which are sometimes performed in the absence of a pelvic organ resection, e.g. testicular cancer with suspicion of lymph node spread) create scarring in the retroperitoneum directly surrounding the blood vessels. Finally, external beam radiation (XRT or radiation therapy) to the pelvis and/or abdomen creates even more scarring within the retroperitoneum, both around the blood vessels and diffusely throughout the tissues making retroperitoneal exposure highly technically difficult. In all cases, the risk of injury to critical structures including the major blood vessels becomes exceptionally high, which is why most consider these to be absolute contraindications. Although retroperitoneal exposure may be contraindicated under these circumstances, for an experienced spinal access surgeon, a transperitoneal (working directly through the abdomen and moving the intestines and other abdominal organs out of the way) approach may still be an option. Also, a lateral spine procedure (OLIF™) may mitigate risk to blood vessels by working away from them during exposure. It is critical that you discuss any prior abdominal surgical procedures, particularly if they fall into the 3 described categories above, with your spinal access surgeon prior to proceeding with any anterior spine procedure.

While a variety of surgical specialists perform anterior spine exposure procedures, relatively few have made a primary practice of this subspecialty. At RMASA, we have dedicated ourselves to the practice of spinal access surgery. This means performing multiple spinal access procedures on a daily basis, leading to a high-volume case experience, with over 2,000 exposures performed to date. Also, this exceptionally high degree of expertise has led to numerous opportunities for advancing techniques through education. Dr. Schoeff has personally trained over 100 surgeons across the country on these surgical approaches and continues to teach and proctor on these advanced techniques. In this highly specialized era of medical and surgical treatment, you want the very best taking care of you, not just someone who occasionally performs these procedures.