Posterolateral Fusion Research Articles

Development and validation of a predictive model and tool for functional recovery in patients after postero-lateral interbody fusion

ObjectiveThe postoperative recovery of patients with lumbar disc herniation (LDH) requires further study. This study aimed to establish and validate a predictive model for functional recovery in patients with LDH and explore associated risk factors.MethodPatients with LDH undergoing PLIF admitted from January 1, 2018 to December 31, 2022 were included, and patient data were prospectively collected through follow-up. The training and validation cohorts were randomly assigned in a 7:3 ratio. To pool data variables LASSO regression was used. The pooled variables were subsequently included in binary logistic regression analyses, construct risk prediction models, and plot nomograms. Additionally, recovery prediction models and interactive web page calculators were developed using R Shiny.ResultsOverall, 1,097 patients with LDH following PLIF were included in this study. Regarding patients’ economic and functional scores, 927 (84.5%) received excellent scores. Key indicators significantly were screened. Multivariate analysis showed that age, season, occupation, HDL-C, smoking, weekly exercise time, and osteoporosis were independent risk factors for postoperative recovery. The C-index of the model was 0.776 (95% CI: 0.7312–0.8208) and 0.804 (95% CI: 0.7408–0.8673) for the training and validation cohorts, respectively. The H–L test showed good fitting of the model (all P > 0.05). The DCA curve showed the best clinical efficacy when the threshold probability was in the ranges of 0–0.71 and 0.79–0.84. The interactive web calculator is accessed at https://postoperativerecoveryofldh.shinyapps.io/DynNomapp/.ConclusionThe predictive tools derived from this study can provide realistic and personalized expectations of postoperative outcomes for patients undergoing lumbar spine surgery.

Synthesis and Preclinical Evaluation of a Novel Oxy133-Infused Biomimetic Bone Graft Using a Rat Model of Posterolateral Spinal Fusion.

To 1) create a novel tissue-engineered bone graft comprising the osteoinductive oxysterol Oxy133 and 2) compare the osteogenic capability of this novel bone graft with bone graft substitutes previously examined. Oxy133 was homogeneously incorporated into a biomimetic (BioMim) bone graft substitute comprising extracellular matrix and calcium phosphates. Two iterations of the graft were created: one corresponding to an implant-dose of 2.0 mg Oxy133 (BioMim-Oxy133-Lo) and the other corresponding to an implant-dose of 20 mg Oxy133 (BioMim-Oxy133-Hi). Thirty-two male Sprague-Dawley rats were allocated randomly to 4 equally sized groups: 1) BioMim-Oxy133-Lo, 2) BioMim-Oxy133-Hi, 3) absorbable collagen sponge (ACS) with topically applied Oxy133 dissolved in dimethyl sulfoxide (ACS-Oxy133; 20 mg Oxy133/graft), and 4) ACS with topically applied recombinant human bone morphogenetic protein-2 (rhBMP-2) dissolved in water (ACS-rhBMP-2; 5.0 μg rhBMP-2/graft). All animals underwent L4-L5 posterolateral spinal fusion. Spines were harvested 8 weeks postoperatively and analyzed using micro-computed tomography imaging. Successful fusion was achieved in all animals. Grafts containing Oxy133 had significantly greater bone volume, percent of bone volume per tissue volume (%BV), bone surface density (BSD), and trabecular number (TbN) compared to ACS-rhBMP-2 (P < 0.01 for each). Animals treated with BioMim-Oxy133-Lo had the greatest %BV, BSD, and TbN (P < 0.001 for each), whereas animals treated with ACS-rhBMP-2 had the lowest %BV, BSD, TbN, and trabecular thickness (P < 0.001 for each). BioMim-Oxy133 is a novel bone graft that led to superior bone volume and quality compared to ACS-rhBMP-2 in a clinically translatable rat model of spinal fusion. Future work is needed to further evaluate this material as a safe and efficacious bone graft substitute.

Open laminectomy plus posterolateral fusion versus open laminectomy plus transforaminal lumbar interbody fusion surgical approaches for fusing degenerated L4-L5 segment: A comparative finite element study

Various finite element (FE) studies reported the biomechanical effects of fusion surgeries in the lumbar spine. However, a comparative study on Open laminectomy plus Posterolateral Fusion (OL-PLF) and Open Laminectomy plus Transforaminal Lumbar Interbody Fusion (OL-TLIF) for fusing an L4-L5 segment has not been reported in the literature. The present comparative FE study evaluates the biomechanical variations in an L4-L5 segment fused using OL-PLF and OL-TLIF surgical approaches. The three-dimensional implanted models were constructed from a computed-tomography scan dataset using image processing software. The models were simulated for the physiological movements such as lateral bending, flexion and extension. The OL-TLIF model had a considerably larger peak equivalent strain than the OL-PLF model under extension (126 %), lateral bending (88 %) and flexion (13 %). However, in both implanted models, a peak equivalent strain above the compressive yield strain limit of the vertebra (0.007) was observed over 60 % of the L4-L5 fused segment, indicating an imminent post-operative bone failure under the imposed loading conditions. The maximum equivalent strain observed in the disc and endplates of the L3-L4 segment was substantially larger to initiate the adjacent segment degeneration. No discernible biomechanical benefits were observed for the OL-TLIF or OL-PLF approaches in fusing the L4-L5 segment.

Comparison of Clinical Outcomes of Conservative Treatment, Percutaneous Intralaminar Stabilization of Pars Defect, and Posterolateral Fusion with Interbody Fusion in Spondylolysis

Aim: This study aimed to compare the clinical efficacy of posterior lumbar interbody fusion (PLIF), percutaneous intralaminar screw pars stabilization (PS), and conservative treatment (CT) for symptomatic spondylolysis (SL). Material and Method: A retrospective randomized study was conducted on 45 patients, with 15 in each group (PLIF, PS, and CT), who underwent bilateral L5 SL and were treated between 2017 and 2022. Surgical indications included low back pain lasting &gt;6 months that was unresponsive to CT and without sciatica. The CT group comprised patients with similar pain profiles. Clinical outcomes were measured using the visual analog scale (VAS), Oswestry Disability Index (ODI), and Short Form 36 (SF-36) scores at 0, 1, 3, 6, and 12 months. Results: The study included 65% female patients with a mean age of 52 (PLIF), 44 (PS), and 46 (CT) years. Both the PS and PLIF groups showed significant clinical improvement compared with the CT group (p

Incorporating Microbial Stimuli for Osteogenesis in a Rabbit Posterolateral Spinal Fusion Model.

Autologous bone grafts are commonly used to repair defects in skeletal tissue, however, due to their limited supply there is a clinical need for alternatives. Synthetic ceramics present a promising option but currently lack biological activity to stimulate bone regeneration. One potential approach to address this limitation is the incorporation of immunomodulatory agents. In this study, we investigate the application of microbial stimuli to stimulate bone formation. Three different microbial stimuli were incorporated in a biphasic calcium phosphate (BCP) ceramic: Bacille Calmette-Guérin (BCG), gamma-irradiated Staphylococcus aureus (γi-S. aureus), or γi-Candida albicans (γi-C. Albicans). The constructs were then implanted in both a rabbit posterolateral spinal fusion (PLF) and an intramuscular implant model for 10 weeks and compared to a nonstimulated control construct. For the PLF model, the formation of a bony bridge was evaluated by manual palpation, micro computed tomography, and histology. While complete fusion was not observed, the BCG condition was most promising with higher manual stiffness and almost twice as much bone volume in the central fusion mass compared to the control (9 ± 4.4% bone area vs. 4.6 ± 2.3%, respectively). Conversely, the γi-S. aureus or γi-C. albicans appeared to inhibit bone formation (1.4 ± 1.4% and 1.2 ± 0.6% bone area). Bone induction was not observed in any of the intramuscular implants. This study indicates that incorporating immunomodulatory agents in ceramic bone substitutes can affect bone formation, which can be positive when selected carefully. The readily available and clinically approved BCG showed promising results, which warrants further research for clinical translation.

Outcome of posterior decompression by L1 laminectomy, transpedicular fixation, posterolateral fusion in burst fracture L1 with incomplete spinal cord injury

Introduction: Burst fractures are more severe than compression fractures as the bones spread out in all directions and may damage the spinal cord, leading to paralysis or nerve injury. This study aims to find the surgical outcomes of Posterior Decompression by L1 Laminectomy in terms of burst fracture with incomplete spinal cord injury. Methods: 48 adult patients with burst fractures with incomplete spinal injury came to NITR from June 2023 to May 2024. In this non-randomized clinical trial, the outcomes of decompression by L1 laminectomy were analysed by using the canal encroachment ratio, while deformity correction was assessed using the sagittal Cobb angle and the percentage of anterior vertebral height for the treatment of L1 burst fracture with incomplete spinal cord injury. Results: The patients were followed up for an average of 12 months. The mean operation time was 154.53 minutes, mean intraoperative blood loss of 48.84 mL, and the mean incision length was 7.78 cm. The canal encroachment ratio decreased significantly, as well as the sagittal Cobb angle, and anterior vertebral percentage height increased. Oswestry Disability Index, and American Spinal Injury Association impairment scale classification were significant. Conclusions: Posterior decompression combined with Transpedicular Fixation and Posterolateral Fusion in the treatment of Burst Fracture L1 with Incomplete Spinal Cord Injury is safe and effective.

A rare case of lumbar facet fracture-dislocation and review of the literature.

Lumbar facet fracture-dislocation is rare, often due to hyperflexion with rotational force. Abnormal scoliosis on radiography is a key sign, prompting further imaging. Facetectomy and laminectomy ensure safe reduction, while instrumented fusion is an effective surgical treatment. Traumatic lumbar facet dislocation is an uncommon condition, particularly when unilateral lumbar facet dislocation is accompanied by a contralateral facet fracture. The patient had a locked facet joint at the left L4-L5, a fracture of the right superior articular process of L5 and a comminuted fracture at the peritrochanteric region of the right femur following a fall. Emergent operation was conducted, starting with open reduction and fixation for the right proximal femur, followed by posterior open reduction and posterolateral fusion with instrumentation, without interbody fusion, for the lumbar spine injury. The patient exhibited positive outcomes throughout the follow-up. This article highlights the trauma mechanism of lumbar facet dislocation, emphasizing hyperflexion with rotational force. Abnormal local scoliosis is a distinctive imaging sign of facet joint dislocation. Facetectomy and laminectomy are recommended for safe reduction and instrumented fusion is considered a safe and effective surgical treatment for facet joint dislocation injuries.

Is ABO blood type a risk factor for adjacent segment degeneration after lumbar spine fusion?

This study aimed to explore associations between ABO blood type and postoperative adjacent segment degeneration/disease (ASD) following lumbar spine fusion, as well as evaluate differences in spinopelvic alignment, perioperative care, postoperative complications, and patient-reported outcome measures (PROMs). An ambispective study was performed. Patients who underwent posterolateral or posterior lumbar interbody fusion were included. Demographic, perioperative and postoperative, clinical, and blood type information was recorded. Pre- and post-operative radiographic imaging was analyzed for alignment parameters and development of ASD. 445 patients were included, representing O+ (36.0%), O- (5.2%), A+ (36.2%), A- (6.3%), B+ (12.1%), B- (1.6%), and AB+ (2.7%) blood types. Most patients were female (59.1%), and had a mean age of 60.3 years and BMI of 31.1kg/m2. Postoperatively, groups did not differ in duration of the hospital (p = 0.732) or intensive care unit (p = 0.830) stay, discharge disposition (p = 0.504), reoperation rate (p = 0.192), or in-hospital complication rate (p = 0.377). Postoperative epidural hematoma was most common amongst A + patients (p = 0.024). Over a mean of 11.0 months of follow-up, all patients exhibited similar improvement in PROMs, with 132 (29.7%) patients developing radiographic evidence of ASD. B + patients were significantly more likely than A + and O + patients to develop spondylolisthesis and ASD (p < 0.05). No significant differences in sagittal alignment parameters and number of levels of fusion were found (p > 0.05). This is the first large-scale study to address and demonstrate proof-of-principle that ABO blood type, a non-modifiable risk factor, is associated with ASD following lumbar spine fusion.

Off-Label Bone Morphogenetic Protein 2 Use Results in Successful Posterolateral Lumbar Fusion in a Veteran Population.

Patients within the US Veterans Health Administration (VA) system have higher rates of comorbidities and chronic pain, increasing risks of complications/poor outcomes following spine surgery. Although the use of bone morphogenetic protein 2 (BMP-2) is established for anterior lumbar interbody fusion, its indications for off-label use in posterolateral fusion are unclear. The objective of this study was to evaluate safety and utility of BMP-2 in posterolateral fusion through a 15-year experience at the VA. Patients underwent posterolateral lumbosacral fusions with BMP-2 by a single VA surgeon from January 1, 2005, to January 1, 2020. The primary outcome was fusion assessed through postoperative radiographs. Secondary outcomes included adjacent segment disease (ASD) and postoperative pain clinic utilization. Sixty-eight patients underwent lumbosacral posterolateral fusion with BMP-2; 77.9% were discharged home and had no postoperative complications. All patients achieved bony fusion at a mean of 113.3 ± 59.9 days postoperatively. Five patients were diagnosed with cancer postoperatively, and eight patients required revision for ASD. No notable predictors of ASD exist. Preoperative opioid use predicted postoperative pain clinic utilization. Posterolateral lumbar fusion with BMP-2 in veterans yields high fusion rates and favorable complication profiles and should be considered in multimorbid hosts. Retrospective review of prospectively collected data.

Ceramic substitutes, failure to achieve solid fusion in posterolateral instrumented fusion: a surgical and histological evaluation

Ceramic substitutes, failure to achieve solid fusion in posterolateral instrumented fusion: a surgical and histological evaluation

3D-ink-extruded titanium scaffolds with porous struts and bioactive supramolecular polymers for orthopedic implants

Porous titanium addresses the longstanding orthopedic challenges of aseptic loosening and stress shielding. This work expands on the evolution of porous Ti with the manufacturing of hierarchically porous, low stiffness, ductile Ti scaffolds via direct-ink write (DIW) extrusion and sintering of inks containing Ti and NaCl particles. Scaffold macrochannels were filled with a subtherapeutic dose of recombinant bone morphogenetic protein-2 (rhBMP-2) alone or co-delivered within a bioactive supramolecular polymer slurry (SPS) composed of peptide amphiphile nanofibrils and collagen, creating four treatment conditions (Ti struts: microporous vs. fully dense; BMP-2 alone or with SPS). The BMP-2-loaded scaffolds were implanted bilaterally across the L4 and L5 transverse processes in a rat posterolateral lumbar fusion model. In-vivo bone growth in these scaffolds is evaluated with synchrotron X-ray computed microtomography (µCT) to study the effects of strut microporosity and added biological signaling agents on the bone formation response. Optical and scanning electron microscopy confirms the ∼100 µm space-holder micropore size, high-curvature morphology, and pore fenestrations within the struts. Uniaxial compression testing shows that the microporous strut scaffolds have low stiffness and high ductility. A significant promotion in bone formation was observed for groups utilizing the SPS, while no significant differences were found for the scaffolds with the incorporation of micropores. Statement of significanceBy 2050, the anticipated number of people aged 60 years and older worldwide is anticipated to double to 2.1 billion. This rapid increase in the geriatric population will require a corresponding increase in orthopedic surgeries and more effective materials for longer indwelling times. Titanium alloys have been the gold standard of bone fusion and fixation, but their use has longstanding limitations in bone-implant stiffness mismatch and insufficient osseointegration. We utilize 3D-printing of titanium with NaCl space holders for large- and small-scale porosity and incorporate bioactive supramolecular polymers into the scaffolds to increase bone growth. This work finds no significant change in bone ingrowth via space-holder-induced microporosity but significant increases in bone ingrowth via the bioactive supramolecular polymers in a rat posterolateral fusion model.

Role of unilateral partial facet joint preservation in postero-lateral approach lumbar interbody fusion for patients with degenerative lumbar spinal stenosis presenting bilateral lower limb symptoms: a retrospective study

BackgroundPosterolateral decompression and fusion with internal fixation is a commonly used surgical approach for treating degenerative lumbar spinal stenosis (DLSS). This study aims to evaluate the impact of preserving a portion of the unilateral facet joint during decompression on surgical outcomes and long-term recovery in patients.MethodsThis study analyzed 73 patients with DLSS accompanied by bilateral lower limb neurological symptoms who underwent single-level L4/5 posterolateral decompression and fusion surgery from January 2022 to March 2023. Patients were categorized into two groups based on the type of surgery received: Group A comprised 31 patients who underwent neural decompression without facet joint preservation, while Group B consisted of 42 patients who underwent neural decompression with preservation of partial facet joints on one side. Regular follow-up evaluations were conducted, including clinical and radiological assessments immediately postoperatively, and at 3 and 12 months thereafter. Key patient information was documented through retrospective chart reviews.ResultsMost patients in both groups experienced favorable surgical outcomes. However, four cases encountered complications. Notably, during follow-up, Group B demonstrated superior 1-year postoperative interbody fusion outcomes (P < 0.05), along with a trend towards less interbody cage subsidence and slower postoperative intervertebral disc height loss. Additionally, Group B showed significantly reduced postoperative hospital stay (P < 0.05).ConclusionUnder strict adherence to surgical indications, the posterior lateral lumbar fusion surgery, which preserves partial facet joint unilaterally during neural decompression, can offer greater benefits to patients.

Load Changes on a Short-Segment Posterior Instrumentation After Transosseous Disruption of L3 Vertebra - A Biomechanical Human Cadaveric Study.

Biomechanical Cadaveric Study. Following the successful use of a novel implantable sensor (Monitor) in evaluating the progression of fracture healing in long bones and posterolateral fusion of the spine based on implant load monitoring, the aim of this study was to investigate its potential to assess healing of transosseous fractures of a lumbar vertebra stabilized with a pedicle-screw-rod construct. Six human cadaveric spines were instrumented with pedicle screws and rods spanning L3 vertebra. The spine was loaded in Flexion-Extension (FE), Lateral-Bending (LB) and Axial-Rotation (AR) with an intact L3 vertebra and after its transosseous disruption, creating an AO B1 type fracture. The implant load was measured on the one rod using the Monitor and on the contralateral rod by strain gauges to validate the Monitor's measurements. In parallel, the range of motion (ROM) was assessed. ROM increased significantly in all directions in the fractured model (P ≤ 0.049). The Monitor measured a significant increase in implant load in FE (P = 0.002) and LB (P = 0.045), however, not in AR. The strain gauge - aligned with the rod axis and glued onto its posterior side - detected an increased implant load not only in FE (P = 0.001) and LB (P = 0.016) but also in AR (P = 0.047). After a complete transosseous disruption of L3 vertebra, the implant load on the rods was considerably higher vs the state with an intact vertebral body. Innovative implantable sensors could monitor those changes, allowing assessment of the healing progression based on quantifiable data.

An evaluation of fusion status following lumbar fusion surgery utilizing multi-planar computed tomography.

To report the rate of fusion in a sample of patients undergoing lumbar fusion surgery and assess interrater reliability of computed tomography (CT)-based parameters for the assessment of fusion. All adult patients who underwent lumbar fusion surgery from 2017 to 2021 were retrospectively identified. Patient demographics and surgical characteristics were collected through chart review of the electronic medical records. CT scans were reviewed independently by two attending spine surgeons and two spine fellows. Fusion was defined as evidence of bone bridging in any one of (1) posterolateral gutters, (2) facets, or (3) interbody (when applicable) on any CT views. Evidence of screw haloing was indicative of nonunion. Interrater reliability was determined using cohen's kappa. Afterwards, a consensus agreement for each component of fusion was reached between participants. The overall fusion rate among all procedures was 63/69 (91.3%). Overall 22/25 (88.0%) TLIF, 16/19 (84.2%) PLDF, 3/3 (100%) LLIF, and 22/22 (100%) circumferential fusions experienced a successful fusion. Interrater reliability was good for interbody fusion (k = 0.734) and moderate for all other measures (k = 0.561 for posterolateral fusion; k = 0.471 for facet fusion; k = 0.458 for screw haloing). Overall, interrater reliability as to whether a patient had a fusion or nonunion was moderate (k = 0.510). There was only moderate interrater reliability across most radiographic measures used in assessing lumbar fusion status. Reliability was highest when evaluating the presence of interbody fusion. The majority of fusions occurred across the facet joints.

Design and development of the additively manufactured Zn-Li scaffolds for posterolateral lumbar fusion

Spinal fusion is a commonly used technique to treat acute and chronic spinal diseases by fusion of the adjacent vertebrae, aiming at achieving stability and eliminating the mobility of the objective segment. While bone autografts and allografts have been conventionally used for spinal fusion, limitations persist in achieving optimization of both good osteoinductive capacity and mechanical stability. In this study, additively manufactured Zn-Li scaffolds were developed and evaluated for their potential in spinal fusion. First, three scaffold structures (BCC, Diamond, and Gyroid) were designed and verified in vitro. Due to the smooth transition surfaces and uniform degradation behavior, the Gyroid Zn-Li scaffold demonstrated mechanical integrity during degradation and enhanced cellular proliferation compared to the other two scaffolds. Subsequently, Zn-Li scaffolds (Gyroid) were selected for posterolateral lumbar fusion (L4/L5) in rabbits. Following 12 weeks of implantation, the Zn-Li scaffolds demonstrated a moderate biodegradation rate and satisfactory biocompatibility. Compared to bone allografts, the Zn-Li scaffolds significantly improved osseointegration adjacent to the transverse processes, which led to enhanced segmental stability of the fused vertebrae post posterolateral lumbar fusion. Overall, the results show that the biodegradable Zn-Li scaffold holds substantial potential as the next-generation graft for spinal fusion.

Local FK506 delivery induces osteogenesis in rat bone defect and rabbit spine fusion models

Bone grafting procedures are commonly used for the repair, regeneration, and fusion of bones in a wide range of orthopaedic surgeries, including large bone defects and spine fusion procedures. Autografts are the clinical gold standard, though recombinant human bone morphogenetic proteins (rhBMPs) are often used, particularly in difficult clinical situations. However, treatment with rhBMPs can have off-target effects and increase surgical costs, adding to patients' already high economic and mental burden. Recent studies have identified that FDA-approved immunosuppressant drug, FK506 (Tacrolimus), can also activate the BMP pathway by binding to its inhibitors. This study tested the hypothesis that FK506, as a standalone treatment, could induce osteogenic differentiation of human mesenchymal stromal cells (hMSCs), as well as functional bone formation in a rat segmental bone defect model and rabbit spinal fusion model. FK506 enhanced osteogenic differentiation and mineralization of hMSCs in vitro. Standalone treatment with FK506 delivered on a collagen sponge produced consistent bone bridging of a critically sized rat femoral defect with functional mechanical properties comparable to naïve bone. In a rabbit single level posterolateral spine fusion model, treatment with FK506 delivered on a collagen sponge successfully fused the L5-L6 vertebrae at rates comparable to rhBMP-2 treatment. These data demonstrate the ability of FK506 to induce bone formation in human cells and two challenging in vivo models, and indicate FK506 can be utilized to treat a variety of spine disorders.

Establishment of a Rabbit Model of Adjacent Intervertebral Disk Degeneration After Lumbar Fusion and Fixation and Evaluation of Autophagy Factor Expression in Nucleus Pulposus Cells.

The objectives of this research were to establish an animal model of adjacent segment degeneration (ASD) bordering lumbar fusion and to investigate the expression of autophagy factors in nucleus pulposus cells of adjacent intervertebral disks. Twenty-four adult New Zealand white rabbits were enrolled and divided into two groups: group A (n=12) and group B (n=12). Posterolateral fusion and fixation were performed after intervertebral disk degeneration occurred in group A, and the rabbits were monitored for 6 months. Group B was the control group and did not undergo fusion surgery. These rabbits were monitored for 6 months. Real-time quantitative polymerase chain reaction and immunohistochemistry were performed to detect the mRNA and protein expressions of PTEN-induced kinase 1 (PINK1), Parkin, ADAMTS-4, and MMP-3. An external database, the GEO database, was used to examine the expression of these genes and analyze them for differential expression. After lumbar fusion in rabbits, the animal model of ASD exhibited gradual degeneration of adjacent intervertebral disks over time. Group A displayed significantly higher mRNA and protein expressions of PINK1 and MMP-3 but lower expression of ADAMTS-4 compared with group B (P<.05). The results analyzed in the GEO database showed that the expression of PINK1 was higher in group A than in group B, while the expression of ADAMTS-4 was lower in group A than in group B. After posterolateral lumbar fusion in rabbits, the animal ASD model showed gradual deterioration of adjacent intervertebral disks with prolonged follow-up. The findings indicate the important role of autophagy in the apoptosis of nucleus pulposus cells in adjacent intervertebral disks. [Orthopedics. 2024;47(4):e167-e173.].

WITHDRAWN: Percutaneous Endoscopic Posterolateral Transforaminal Lumbar Interbody Fusion for the Treatment of Lumbar Degenerative Disease

Percutaneous endoscopic lumbar interbody fusion (PE-LIF) is commonly employed in treating a variety of lumbar degenerative diseases (LDD). This study evaluated the effectiveness and safety of a modified approach known as percutaneous endoscopic posterolateral transforaminal lumbar interbody fusion (PE-PTLIF). We conducted a retrospective review of 46 patients who underwent PE-PTLIF for LDD between November 2020 and July 2021. We analyzed measurements including pre- and postoperative Visual Analogue Scores (VAS) for lower back and leg pain, Oswestry Disability Index (ODI) collected at 3 days, 3 months, 6 months, and the most recent follow-up, and spinal parameters (disc space height, lumbar lordosis angle, and lumbar spondylolisthesis rate) over time. Patients were followed for an average duration of 18.6 months. Significant improvements were observed in VAS scores for lower back pain (latest follow-up: 1.21 ± 0.57) and leg pain (latest follow-up: 1.10 ± 0.72), as well as in ODI scores (latest follow-up: 9.63% ± 4.13) (all P<0.001 compared with preoperative values). Improvements were also noted in vertebral space height and lumbar lordotic angles (P<0.001). Postoperative complications included wound infection (6.5%), cerebrospinal fluid leakage (2.2%), and reduced dorsiflexion muscle strength (2.2%), all of which were successfully managed conservatively. There were no instances of epidural hematoma, internal fixation failure, or lumbar non-fusion/fusion device displacement. Confirmation of osseous fusion was obtained via lumbar X-ray/CT scans at the final follow-up. PE-PTLIF is a promising treatment option for specific LDD including spinal stenosis, lumbar spondylolisthesis, and lumbar instability, with favorable therapeutic outcomes demonstrated.

Efficacy of Biphasic Calcium Phosphate Ceramic With a Needle-Shaped Surface Topography Versus Autograft in Instrumented Posterolateral Spinal Fusion.

A multicenter randomized controlled noninferiority trial with intrapatient comparisons. The aim of this study was to determine noninferiority of a slowly resorbable biphasic calcium phosphate with submicron microporosity (BCP<μm, MagnetOs Granules) as an alternative for autograft in instrumented posterolateral fusion (PLF). Successful spinal fusion with a solid bone bridge between the vertebrae is traditionally achieved by grafting with autologous iliac bone. However, the disadvantages of autografts and unsatisfactory fusion rates have prompted the exploration of alternatives, including ceramics. Nevertheless, clinical evidence for the standalone use of these materials is limited. Adults indicated for instrumented PLF (1 to 6 levels) were enrolled at 5 participating centers. After bilateral instrumentation and fusion-bed preparation, the randomized allocation side (left or right) was disclosed. Per segment 10 cc of BCP<μm granules (1 to 2mm) were placed in the posterolateral gutter on one side and 10 cc autograft on the contralateral side. Fusion was systematically scored on 1-year follow-up CT scans. The study was powered to detect >15% inferiority with binomial paired comparisons of the fusion performance score per treatment side. Of the 100 patients (57 ± 12.9 y, 62% female), 91 subjects and 128 segments were analyzed. The overall posterolateral fusion rate per segment (left and/or right) was 83%. For the BCP<μm side only the fusion rate was 79% versus 47% for the autograft side (difference of 32 percentage points, 95% CI, 23-41). Analysis of the primary outcome confirmed the noninferiority of BCP<μm with an absolute difference in paired proportions of 39.6% (95% CI, 26.8-51.2; p < 0.001). This clinical trial demonstrates noninferiority and indicates superiority of MagnetOs Granules as a standalone ceramic when compared to autograft for posterolateral spinal fusion. These results challange the belief that autologous bone is the most optimal graft material.

The Role of L1PA in Patient-reported Outcomes in Patients Undergoing Single-level Lumbar Fusion for Degenerative Spondylolisthesis.

Retrospective cohort study. To determine whether the L1 pelvic angle (L1PA) can be used to predict quality of life outcomes for adults one year after L4-L5 fusion to treat degenerative spondylolisthesis. L1PA is beneficial in the evaluation of preoperative and postoperative quality of life outcomes in patients undergoing surgery for spinal deformity. No studies have examined its utility in surgical patients with degenerative spinal disease. Patients undergoing L4-L5 posterolateral decompression and fusion or transforaminal lumbar interbody fusion for degenerative lumbar spondylolisthesis were grouped by preoperative and postoperative L1PA, and further stratified by cut offs of >7.2° and <7.2° based on previous literature. We also stratified patients by presence of an ideal calculated L1PA, defined as (0.5×Pelvic incidence) -21 +/-5°, as proposed by prior literature. Preoperative, one-year postoperative and Δ (postoperative minus preoperative) patient-reported outcome measures (PROMs) and radiographic measurements were collected. Twenty-four patients were identified with preoperative L1PAs <7.2° and 132 with L1PAs >7.2°. Eighteen patients were identified with postoperative L1PAs <7.2° and 138 with L1PAs>7.2°. Sixty-five and fifty-seven patients were identified as having ideal calculated preoperative and postoperative L1PAs, respectively. When using absolute cutoffs, L1PA correlated with pelvic tilt, pelvic incidence, and pelvic incidence-lumbar lordosis mismatch (PI-LL). When using calculated L1PAs, L1PA correlated with lumbar lordosis, PI-LL, pelvic tilt and sacral slope. With respect to PROMs, no statistically significant differences existed between cohorts both preoperatively and at one-year postoperatively on either univariate and multivariate analyses. L1PA may be a helpful radiographic consideration that translates to clinically relevant outcomes in spinal deformity. However, it does not appear as predictive of patient outcomes after single-level fusion for patients with L4-L5 degenerative spondylolisthesis. Further studies are warranted to investigate the role of L1PA in degenerative spine patients.