INTRODUCTION: Posterior lumbar fusion is a common technique used to stabilize the lumbar spine. However, complications such as cranial facet violations, blood loss, and soft tissue damage have led to interest in minimally invasive alternatives. Transfacet screws have emerged as a viable option, offering benefits including reduced adjacent segment degeneration and lower blood loss, particularly valuable for patients with osteopenia, osteoporosis, or pre-existing adjacent segment issues. The purpose of this study was to investigate outcomes in patients undergoing one- or two-level lumbar transfacet screw implantation.
METHODS: The study was based on a consecutive series of 31 patients treated with transfacet screws. The inclusion criteria consisted of patients who underwent a posterior fusion using transfacet screws or translaminar facet screws performed on either 1 or 2 levels, 3) had at least 1-year follow-up, and 4) were at least 18 years of age. Patients were excluded if they: 1) previously underwent prior lumbar fusion, disc replacement, or vertebroplasty, 2) were treated for spinal deformity, or 3) were diagnosed with cancer. Data were collected from clinic charts and operative notes for surgical details. The outcome measures examined in this study were clinical outcomes consisting of Oswestry Disability Index (ODI) scores, visual analog scale (VAS) back and leg pain, reoperations, and occurrence of screw removal. Any lumbar reoperations after transfacet implantation were recorded, for which details were recorded, such as reason for reoperation, levels operated, and transfacet screw removal or additional fixation. For each case of screw removal, the reason, time from index surgery, and procedure performed were recorded.
RESULTS: The mean age of the patients was 53.3 years (range 26-83 years), and 54.8% of the patients (n=17) were male. All patients were being treated for at least one of the following: stenosis, spondylolisthesis, facet hypertrophy, and disc degeneration. Most (71%) of these operations were part of a combined interbody with posterior fusion. There were 82 screws implanted over 41 levels, with 48 screws being translaminar facet screws and 34 being transfacet screws. The mean follow-up duration was 45 months (range 12-129 mo.). There was a statistically significant improvement from pre- to postoperative ODI (40.1 vs 23.1; p<0.001), back pain (6.4 vs 2.7; p<0.001), and leg pain (4.7 vs 2.3; p<0.005). Six patients (19.4%) underwent a lumbar reoperation; however, three of these reoperations (50%) were performed to address existing pathology not addressed during the initial operation, pursuing a more conservative, stepwise treatment plan. Time from index to reoperation was shorter on average for continued symptomatic patients (19.7 months) than those who developed symptoms for new pathologies (49.7 months). Five of the six reoperations (83.3%) involved use of transfacet screws at additional levels.
DISCUSSION: This study found that the use of transfacet screws produced significant improvement in pain and self-reported function. This procedure appears to be a viable alternative to traditional pedicle screws and rods.