Advantages of Spinal Fusion: TLIF versus PSF

Back pain is a condition that millions of Americans deal with each year. Most often, lower back pain will resolve after a few weeks without any need for medical intervention. In other cases, conservative measures like chiropractic care or physical therapy can reduce pain. For a small number of patients, these methods do not work, and spinal surgery is their final option. These select candidates are looking for a solution to their pain that will enable them to live as comfortably as possible.

Advantages of Spinal Fusion

Lumbar fusion surgery is a minimally invasive approach to treating conditions that cause instability in the lower back. When the spine and discs start to degenerate and herniate, the spine becomes more prone to movement, which causes misalignment and pinched nerves. Herniated discs occur as a result of degenerating discs leaking their jelly-like insides onto the surrounding spinal anatomy. When this substance puts pressure on nerves, the pain can be debilitating. In lumbar fusion surgery, the spine is approached to remove all or part of the herniated disc from the two vertebrae it rests between. Then, the vertebrae are fused on either side of the remaining disc space using bone grafts.

Using a minimally invasive approach, surgeons use endoscopes that have cameras on the end. The small camera is then able to project the site of the surgical process onto large video screens in the operating room. This approach is very beneficial for patients. Cosmetically, it prevents large incisions, which leave large scars. In addition, smaller incisions mean that less of the surrounding tissues are impacted and interfered with during surgery. The goal of surgery is for the patient to heal well and minimally invasive surgery speeds up this process. With lowered risk for infection, patients are also in the hospital for shorter periods of time. They are also able to begin their post-surgery rehabilitation more quickly because smaller incisions heal faster.

Transforaminal Interbody Fusion (TLIF)

In this method, the surgeon approaches the damaged lumbar spine from the back. The goal of this surgery is to place a bone graft between two vertebrae. This is what separates interbody fusions from posterolateral fusions. In the former, the bone graft is placed where the disc usually lies. Bone graft is usually taken from the pelvis and placed in the space between the vertebrae that are being fused. Screws and rods are attached to the bones to ensure optimal fusion. In the months after the surgery, the bone graft fuses to the other vertebrae, forming one long bone.

Posterolateral Spine Fusion (PSF)

In this approach, surgeons place the bone graft on the transverse processes in the back of the spine. Compared to TLIF, where the graft is placed in the disc space, PSF has the graft on the outer part of the vertebrae that are being fused together. The surgeon uses screws and rods to connect the two grafts on the outside of each vertebra. The grafts are connected with a metal rod. Depending on the grade of the fusion, more or fewer screws and rods are used.


A recent study published in The Journal of Spinal Disorders and Techniques examined how patients who underwent either PSF or TLIF recovered and measured the overall effectiveness of the surgeries. Here were some of the findings of the study:

  • All patients in both groups reported a significant improvement in their pain levels when compared with the baseline before the surgery.
  • For patients being treated for spondylolisthesis and disc pathology, the results were similar for TLIF and PSF patients.
  • For postdecompression instability, TLIF outperformed PSF for every outcome measure. Those who underwent TLIF had more stable spines.
  • Those who underwent minimally invasive TLIF had reduced postoperative narcotic use and quicker returns to work. On average, patients were back at work in 8.5 weeks, compared to 17.1 weeks for patients who had open surgery.

The conclusions to be taken from this study are that though both surgical options improved patients’ symptoms, TLIF was the more effective approach for promoting long-term spinal stability.

If you are experiencing back pain that has lasted longer than a few weeks, it may be time to be evaluated by a physician. There are many treatment options for back pain but you need a diagnosis before any of these treatments can begin. At The Center for Musculoskeletal Disorders, our team of orthopedic physicians is experienced in treating back pain with both surgical and non-surgical approaches.