ABSTRACT
Background: Pain and disability due to age-related spinal disorders are increasing due to a more active population placing greater demands on their musculoskeletal system. For patients requiring surgery, spinal fusion is typically indicated. Interbody fusion cages improve fusion rates and restore lordosis, disc height, and foraminal height. Static cages are offered in multiple conformations to account for anatomic variability; however, they have issues related to implant subsidence and loss of lordosis. Expandable cages were developed to address these drawbacks. Methods: Patients treated with either static or expandable transforaminal lumbar interbody fusion devices (ProLift® Expandable Spacer System) for the treatment of spondylolisthesis, degenerative disc disease, spinal stenosis, disc herniation, or degenerative scoliosis at L4-L5 or L5-S1 were chosen from retrospective data. Outcomes included radiographic and spinopelvic changes, patient-reported outcomes, and incidence of non-union and revision surgery. Results: One hundred patients were included (Static: 50; Expandable: 50). Demographics between groups were similar, with some differences in comorbidities and spinal disease diagnosis. Radiographically, changes in disc height, foraminal height, and lordosis were significantly improved in the Expandable group up to 2 years (P<0.001). Improvements in patient reported outcomes were more favorable in the Expandable group. Conclusions: In patients who underwent transforaminal lumbar spinal fusion via minimally invasive surgery, the Expandable device group demonstrated significantly improved radiographic and patient reported outcomes compared to a static cage over 2 years.
ABSTRACT
BACKGROUND: This report documents 1-year results of 250 patients enrolled in a prospective, multicenter study of a minimally invasive (MI) sacroiliac joint fusion (SIJF) system that uses decortication, graft placement, and joint fixation. METHODS: The cohort includes all patients enrolled in the EVoluSIon (EVSI) clinical study who had MI SIJF surgery and completed 1-year follow-up. Average age at baseline was 60.5 years, and 70.8% were female. Sacroiliac (SI) joint-related pain duration was ≥2 years in 56% of patients. Visual analog scale (VAS) SI joint pain, Oswestry Disability Index (ODI), quality of life, and opioid use were assessed preoperatively and at 1 year. RESULTS: At 1 year, the mean VAS pain demonstrated a significant reduction of more than 43 points, from 76.4 at baseline to 33.0 (P < 0.0001), with 72.2% of patients attaining the minimal clinically important difference (MCID, ≥20-point improvement). Mean ODI scores also significantly improved from 54.4 at baseline to 30.5 at 1 year (P < 0.0001), with 62.5% of patients achieving the MCID (≥15-point improvement). Prior to surgery, 62.7% (126/201) of patients were taking opioids or other narcotics, but by 1 year postsurgery, only 26.9% (54/201) of patients reported using these medications, representing a significant 57.1% decrease in narcotic/opioid use (P < 0.0001). Fusion of the SI joint was seen in 68.7% of patients. Few procedural complications were reported. In all, there were 8 (8/250) serious procedure-related events, including 1 device malposition observed on the day of surgery that required replacing the superior screw with a shorter screw. CONCLUSIONS: Analysis of patients treated with MI SIJF in the EVSI study demonstrated that the procedure can be performed safely and results in significant improvements in pain, quality of life, and opioid use at 1 year as well as causing fusion in the majority of patients. CLINICAL RELEVANCE: MI SIJF differs from most procedures currently being performed in that it applies true orthopedic principles with decorticating, bone grafting, fusion, and placement of implants perpendicular to the joint for greatest stability. The 12-month data show improvement in functionality, reduction in pain, and, most notably, a reduction in narcotic usage, which is important considering the ongoing opioid epidemic.
ABSTRACT
Introduction Minimally invasive spine surgery has become more prevalent in recent years, but the delivery of interbody devices with small footprints may insufficiently restore the disc space, which may lead to instability and non-union. Vertically expandable interbody implants have partially addressed this limitation, but lateral fusion support remains a concern. The purpose of this study was to evaluate two-year safety and effectiveness outcomes with a multidimensional, expandable interbody fusion device (Luna 3D Interbody Fusion System, Benvenue Medical, Inc., Santa Clara, CA) that is delivered through a minimally invasive approach (6-8 mm) that expands in situ to approximate an anterior lumbar interbody fusion footprint of 25 mm diameter. Material and methods This was a retrospective, single-center study that evaluated the clinical utility of a multi-expandable interbody cage in patients undergoing posterior or transforaminal lumbar interbody fusion. Key patient-reported outcomes included back pain severity, leg pain severity, and the Oswestry Disability Index (ODI). Radiographic assessments included disc height (anterior, posterior, and average), foraminal height, segmental lordosis, subsidence, implant migration, and pseudarthrosis. Patients were followed at regular intervals over two years postprocedure. Results A total of 50 consecutive patients were treated with transforaminal lumbar interbody fusion (TLIF) using the multidimensional expandable implant. Procedural blood loss was minimal (median 200 ml) and the mean hospital stay was 2.1 days. Perioperative complications were reported in three patients and included a dural tear, postoperative ileus, and end-plate violation. All complications were successfully managed conservatively. There were no nerve root injuries or perioperative infections. Over the two-year follow-up period, one case of subsidence and one case of implant migration were noted on radiographic imaging but required no treatment. Comparing the values reported at baseline and two years, the mean ODI score decreased by 61%, back pain severity decreased by 67%, and leg pain severity decreased by 80% (all p<0.001). Comparing radiographic measures from baseline to two years, anterior disc height increased from 7.6 mm to 15.5 mm, posterior disc height increased from 2.9 mm to 10.1 mm, average disc height increased from 5.6 mm to 13.3 mm, foraminal height increased from 12.2 mm to 20.2 mm, and segmental lordosis increased from 6.2 degrees to 14.0 degrees (all changes p<0.001). One case of non-union was observed and the corresponding two-year fusion rate was 98%. Conclusions The utilization of a minimally invasive, multidimensional, expandable interbody implant was safe and effective over two years of clinical follow-up. The implant allows the surgeon to re-establish sagittal balance and to provide a larger surface area for fusion as compared to traditional minimally invasive interbody devices.
ABSTRACT
The increasing adoption of minimally invasive techniques for spine surgery in recent years has led to significant advancements in instrumentation for lumbar interbody fusion. Percutaneous pedicle screw fixation is now a mature technology, but the role of expandable cages is still evolving. The capability to deliver a multiexpandable interbody cage with a large footprint through a narrow surgical cannula represents a significant advancement in spinal surgery technology. The purpose of this report is to describe a multiexpandable lumbar interbody fusion cage, including implant characteristics, intended use, surgical technique, preclinical testing, and early clinical experience. Results to date suggest that the multiexpandable cage allows a less invasive approach to posterior/transforaminal lumbar interbody fusion surgery by minimizing iatrogenic risks associated with static or vertically expanding interbody prostheses while providing immediate vertebral height restoration, restoration of anatomic alignment, and excellent early-term clinical results.
