Biomechanical analysis of pedicle screw density and rod contouring in adolescent idiopathic scoliosis instrumentation.

The learning curve of robotic assisted pedicle screw placement: individual patient data meta-analysis.

Comparison of pedicle screw loosening under uniaxial and multiaxial loading.

Objective: This study aimed to evaluate the stability of cement-augmented pedicle screws in patients with osteoporosis of the thoracolumbar spine, with a focus on reducing mechanical failures compared with non-augmented screws.Methods: A retrospective analysis was conducted on 119 patients who underwent thoracolumbar fusion surgery between 2011 and 2022. The incidence of mechanical failures—including pull-out, screw loosening, and cage protrusion—was compared between patients treated with cement-augmented pedicle screws and those without augmentation.Results: Cement augmentation was associated with a significant reduction in overall mechanical failures. The incidence of mechanical failure was significantly lower in the cement-augmented group compared with the non-augmented group (20.4% vs. 41.4%, p=0.018). Although individual complications such as pull-out, cage protrusion, and screw loosening were less frequent in the cement-augmented group, these differences were not statistically significant. However, the overall reduction in mechanical failures was statistically significant. Fusion rates were higher in the cement-augmented group than in the non-augmented group, although the difference was not significant (79.6% vs. 70.0%, p=0.337). Importantly, patients without mechanical failures had significantly higher fusion rates than those with failures (82.5% vs. 56.41%, p=0.0048).Conclusions: Cement-augmented pedicle screws significantly reduce the risk of mechanical failures in thoracolumbar fusion surgery for patients with osteoporosis. Mechanical stability strongly influences fusion success, highlighting the importance of preventing mechanical failure to optimize surgical outcomes. These findings support cement augmentation as an effective strategy to enhance the durability of pedicle screw fixation and should be considered in surgical planning for patients with osteoporosis.

Adolescent idiopathic scoliosis refers to spinal deformity that develops from just before the onset of puberty until the completion of skeletal growth, and the primary goal of treatment is to achieve a well-balanced spine. In the late 1990s, advances in the anatomical understanding of the spine and the development of fixation instruments made posterior pedicle screw insertion feasible, thereby enabling the transmission of powerful corrective forces for deformity correction. Over the subsequent decades, accumulated clinical experience and outcomes have provided a deeper understanding of scoliotic curves and led to the establishment of effective principles for determining the extent of spinal fusion. However, these treatment principles are based on the unique biomechanics and procedural characteristics of scoliosis correction surgery, which can make them difficult to understand without sufficient explanation. In this review, we aim to describe these established treatment principles and surgical processes in detail using schematic illustrations and images. Although these principles will continue to undergo new challenges and validation over time, they will remain a meaningful reference point for those exploring alternative strategies.

To compare modified transforaminal lumbar interbody fusion (M-TLIF) and posterior lumbar interbody fusion (PLIF) in patients with lumbar degenerative disease complicated by osteoporosis who underwent bone cement-augmented pedicle screw placement, with a focus on lumbar radiographic parameters and clinical outcomes. A retrospective comparative study was conducted on patients with lumbar degenerative disease and osteoporosis who underwent lumbar fusion surgery with bone cement-augmented pedicle screws between January 2021 and June 2023. Based on the surgical procedure received, patients were divided into an M-TLIF group (n = 49) and a PLIF group (n = 44). The comparison encompassed perioperative indicators, radiographic parameters-including the coronal Cobb angle, average surgical segment disc height (ASDH), lumbar lordosis (LL), segmental lordosis (SL), Bridwell fusion grade, and Marchi subsidence grade-and clinical efficacy scores, including the visual analog scale (VAS), Oswestry Disability Index (ODI), and Japanese Orthopedic Association (JOA) score, which were assessed preoperatively, immediately postoperatively, and at 2-year postoperatively. The study included 93 patients (M-TLIF: n = 49; PLIF: n = 44). The two groups were comparable in all baseline characteristics (P > 0.05). Regarding perioperative indicators, the M-TLIF group had a significantly longer operative time per segment (185.79 ± 78.46min vs. 152.92 ± 71.64min, P = 0.038) but a lower volume of bone cement used per screw (1.86 ± 0.58ml vs. 2.15 ± 0.62ml, P = 0.023). Both groups demonstrated significant improvements in all clinical scores (VAS, ODI, JOA) and radiographic parameters (Cobb, ASDH, LL, SL) at all postoperative time points compared to preoperative values (all P < 0.05). At the 2-year postoperatively, VAS and ODI scores were comparable between groups (P > 0.05). Although the JOA score was statistically higher in the PLIF group (25.73 ± 1.26 vs. 25.12 ± 1.51, P = 0.040), the absolute difference of 0.61 points is clinically negligible. Radiographically, the PLIF group achieved a significantly greater SL angle at follow-up (16.59 ± 8.59° vs. 12.17 ± 8.16°, P = 0.013), while the M-TLIF group showed a significantly superior Bridwell fusion grade (P = 0.020). There was no significant intergroup difference in cage subsidence (P > 0.05). Both M-TLIF and PLIF effectively improved the clinical symptoms and radiographic parameters of these patients, with equivalent clinical efficacy in relieving pain and restoring function. The choice of procedure can be individualized: M-TLIF is preferred when superior interbody fusion is the priority, while PLIF is more suitable for achieving greater segmental lordosis.

To investigate the effects of adjacent-segment biomechanics at the cervicothoracic junction using different fixation constructs. Six human cadaveric spine specimens (C5-T4) were analyzed for range of motion (ROM) in the intact condition. All specimens were destabilized and reconstructed using 4.0-mm pedicle screws at T1-T3. Two constructs included interlaminar hooks at C6 and C7 with 3.5- or 4.0-mm rods (C6-T3). Two constructs included lateral mass screws at C6 and pedicle screws at C7, with 3.5- or 4.0-mm rods (C6-T3). Two screw-connector-rod constructs included lateral mass screws at C6 and pedicle screws at C7, with 3.5- or 4.0-mm rods; 1 rod spanned C6-C7 with a connector to a second rod of the same size spanning T1-T3. ROMs at upper and lower adjacent levels were compared with the intact condition. Upper adjacent ROMs for C6-T3 screw-rod fixation with either rod size did not differ from the intact condition in any direction (P > .78). Screw-connector-rod fixation ROM with either rod size did not differ from the intact condition in any direction (P > .07). ROMs for upper adjacent hook-rod constructs were significantly less for both rod sizes than that of the intact condition in all directions (P < .006). The lower adjacent constructs did not differ with either rod size from the intact condition (P > .3). The adjacent-segment motion magnitude was dictated by construct composition at the cervicothoracic junction. Although screw constructs provided an adjacent-level ROM most like that of the intact condition, hook constructs provided a smooth transition by limiting adjacent-segment ROM.

Study DesignProspective Cohort Study of 108 cases.ObjectiveProne Transpsoas (PTP) fusion is a minimally invasive surgical technique using a single-position prone lateral approach to augment the anterior column of the lumbar spine. Degenerative spondylolisthesis (DS) is a common pathology where anterior-posterior access can be advantageous. This study aimed to evaluate operative, radiological and functional outcomes of PTP fusion in the management of symptomatic DS.MethodsA multi-centre cohort study was conducted, involving 108 consecutive patients who underwent PTP fusion for low-grade (Grade I-II) DS. Descriptive statistical analysis was used to evaluate clinical, radiological and functional outcomes.ResultsIn all 108 cases, anterior column fusion was combined with posterior percutaneous pedicle screw fixation to optimise spinal realignment. The cohort's average operative time was 115minutes, and the psoas retraction time was 14minutes. The cohort had an average slip of 5.9mm, which was reduced to 0.8mm (P < 0.001) postoperatively. Statistically significant radiological improvements were observed in lumbar lordosis (Δ5°), segmental lordosis (Δ4°), anterior disc height (Δ 4.2mm) and posterior disc height (Δ 2.1mm). No major vascular or visceral complications were encountered. The sustained neurological complication rate was 1.9%, and patients maintained improved functional outcomes through the 1-year follow-up.ConclusionsPTP is a safe approach for managing low-grade DS, showing significant postoperative correction of spinal alignment. These results support the use of PTP fusion for treating spondylolisthesis and add to the growing evidence of its safety and efficacy as a minimally invasive technique.

Posterior pedicle screw instrumentation is usually used for patients with thoracolumbar burst fractures. Some scholars have suggested that pedicle fixation at the level of the fracture to improve stability, prevent postoperative loss of correction and reduce the risk of internal fixation failure. However, for patients with a load sharing classification (LSC) score ≤ 6, whether additional screws are needed in the fractured vertebra is unknown, and there is no standard treatment plan. In this prospective randomized controlled study, the imaging parameters and clinical outcomes before surgery were compared with those after surgery and during the follow-up period. In this study, patients were randomly divided into the posterior short-segment pedicle fixation with injured vertebra fixation (PSPFI) group and the posterior short-segment pedicle fixation (PSPF) group using a digital randomization sequence. Clinical and radiographic parameters were evaluated before surgery, after surgery and at the follow-up. The imaging parameters included intervertebral disc height (IDH), anterior vertebra height (AVH), the Cobb angle (Cobb), and loss of the corrected AVH (AVH loss) and Cobb angle (Cobb loss). The Oswestry Disability Index (ODI) score and visual analog scale (VAS) score were recorded as parameters for evaluating clinical outcomes. A total of 150 patients met the inclusion criteria (75 patients each in the PSPFI and PSPF groups). There were no significant differences in the demographics between the two groups. PSPFI was superior to PSPF in the level of correction maintained. PSPF was superior to PSPFI in terms of short-term postoperative correction. However, there was no significant difference between the groups. Moreover, the differences in the VAS and ODI scores were not significant. But the PSPF group had a shorter operation time (P 0.001) and a lower blood loss (P 0.002). The effect of posterior pedicle screw internal fixation for thoracolumbar fractures is good, with or without the use of intermediate screws, and there is no significant difference in the long-term follow-up data. Owing to its short operation time and low intraoperative blood loss, short-segment pedicle fixation without injured vertebra fixation is worthy of widespread application in clinical practice.

Background: Neurofibromatosis 1 is an autosomal dominant disorder accompanied by extensive early-onset spinal manifestations, with or without dystrophic scoliotic features. While non-dystrophic subtypes can often be treated similarly to idiopathic scoliosis, dystrophic scoliosis typically requires more aggressive intervention, often involving instrumentation in severely compromised pedicles or vertebrae. Purpose: This review aims to present recent advances in the surgical treatment of Neurofibromatosis 1-associated scoliosis, including surgical techniques and emerging guidance methods. Methods: An electronic literature search was conducted in Web of Science and PubMed to identify surgical techniques for scoliosis in patients with Neurofibromatosis 1. Results: Forty-one studies on the operative treatment of dystrophic scoliosis or both subtypes were retrieved. Although aggressive treatment with combined anterior and posterior fusion are widely used, posterior-only methods, which avoid plexiform tumours, present encouraging results. Recent studies highlight the effectiveness of growing rod systems in early-onset cases, enabling delayed fusion while preserving T1-S1 growth. Promising results from sectional or segmented correction techniques demonstrate better sagittal balance and Cobb angle correction, respectively. Preoperative use of halo-gravity traction, which has been extensively studied, is associated with reduced neurological impairment and encourages better correction results, avoiding autofusion. Various studies have also reported more precise pedicle screw placement with guidance of O-arm and triggered electromyography (t-EMG). Conclusions: The correction of spinal scoliotic deformities presents a significant challenge. However, recent advances in surgical techniques and intraoperative guidance offer promising strategies for more effective management.

Due to the rarity of spinal epithelioid malignant peripheral nerve sheath tumor (EMPNST), the diagnosis, treatment and prognosis of this condition are limited. A 67-year-old male patient presented to our hospital with pain in his right shoulder. Imaging studies identified a T2 spinal tumor. The patient underwent T2 vertebral tumor subtotal resection, spinal canal decompression, and C7-T4 percutaneous pedicle screw fixation because he had shown signs of spinal cord compression. Postoperatively, H&E staining revealed numerous malignant tumor cells with epithelioid characteristics. Immunohistochemical analysis of the tumor cells demonstrated weak positivity for cytokeratin, a TP53 mutation, and retained expression of H3K27me3 and SMARCB1/INI1. The cells were negative for S-100, Sox-10, HMB-45, ALK-1, CD23, CD30, CD34, Desmin, epithelial membrane antigen, smooth muscle actin, and Stat6. Based on these findings, a diagnosis of EMPNST was established. On the 10th day following the initial surgery, swelling was observed at the surgical incision site. Subsequent imaging studies confirmed tumor progression. A comprehensive strategy that integrated surgical resection with intraoperative radiotherapy (IORT) and postoperative radiotherapy were implemented; however, these interventions did not yield favorable results. Unfortunately, the patient passed away shortly after treatment. We present a rare case of spinal EMPNST that was negative for both S-100 protein and SOX10, while retaining expression of SMARCB1/INI1. Notably, the patient did not benefit from IORT and postoperative radiotherapy because these treatments failed to stop the fast tumor growth or enhance neurological results in this particular situation.

To study the biomechanical effects of tilting titanium cages on internal fixation devices in TES surgery. We used finite element analysis to simulate lumbar total en bloc spondylectomy (TES). Five models were constructed:(a) the intact model (L1-S); (b) the TES model after L3 removal; and the TES model with a titanium cage tilted at (c) 5°, (d) 10°, or (e) 15° in the sagittal plane. The sacrum was fixed to simulate the stress during lumbar flexion, extension, lateral bending to the left and right, and rotation to the left and right, and measured the biomechanical response of the internal fixation system. The range of motion (ROM) in segments L1-5 of the TES surgical model was significantly reduced compared to the intact model, with a decrease of 66.87-96.49%. The maximum von Mises stress (VMS) in the pedicle screw system occurred during left lateral bending, reaching 283.9MPa, while the minimum VMS occurred during flexion, at 114.7MPa; during rotation, the maximum endplate stress was observed at L2 and L4, with values of 30.8MPa and 22.7MPa, respectively. When comparing the tilted cage models c-e to the neutral cage model b , the ROM of the lumbar spine most notably increased during left and right rotations, with an increase of 166.5%-227.6%. The VMS in the pedicle screw-rod system significantly increased during rotation, with a peak value of 421.3MPa, and the VMS in the titanium cage also showed a marked increase, with a maximum value of 733.5MPa. The VMS of the lower endplate at L2 increased to a range of 21.6MPa to 113.0MPa, and the VMS of the upper endplate at L4 increased to a range of 12.0MPa to 66.9MPa. After the titanium cage is tilted, the pedicle screw-rod system, the titanium cage, and the upper and lower endplates of the adjacent vertebrae all experience an increase in stress. This stress elevation is most critical during rotational movements. Although the stress values fluctuated across different tilt angles (5°, 10°, 15°), no consistent dose-response relationship was observed in this model. This suggests that the presence of sagittal tilt itself may be a more critical factor influencing stress than the exact degree of tilt within the 5°-15° range.

Accurate pedicle screw placement is essential yet challenging in spinal surgery. This trial evaluated whether a robotic system with biplane fluoroscopic positioning could improve accuracy, efficiency, and safety compared to conventional fluoroscopy-guided techniques. This multicenter, parallel-group, randomized trial was conducted at three hospitals. A total of 70 patients requiring pedicle screw fixation were randomly assigned (1:1) to either the robot-assisted group (RG) or the conventional fluoroscopy-guided group (CG). In the RG, a robotic navigation system assisted in planning and localizing the guide pin entry point and trajectory, based on a biplane algorithm that integrated anteroposterior and lateral fluoroscopic images with optical tracking data to achieve real-time spatial registration. This biplane positioning technique was derived from the principles of the Dual Fluoroscopic Imaging System (DFIS). In the CG, guide pin placement was performed under conventional fluoroscopic guidance. The primary outcome was the deviation of guide pin placement. Secondary outcomes included the cumulative number of exposures, total radiation dose, operative time, average time to establish a single channel, and number of channel adjustments. The mean deviation of guide pin placement in the RG was significantly smaller than that in the CG (0.86±0.57mm vs. 2.55±1.88mm, P<0.001). The RG also had significantly fewer cumulative number of exposures (4.56±1.70 vs. 13.38±19.01, P=0.003) and lower total radiation doses (7.35±3.33 μSv vs. 30.28±97.41 μSv, P=0.024). The operative time was similar between the groups (245.03±67.06min vs. 215.18±83.08min, P=0.083). The number of channel adjustments was significantly lower in the RG (0.06±0.29 vs. 0.28±0.90, P=0.014). There were no significant differences in the incidence of adverse events between the two groups. The robotic system with biplane fluoroscopic positioning improved guide pin accuracy and reduced radiation exposure, indicating its potential to enhance precision and safety in spinal surgery.

Prospective, multicenter, single-blind, randomized, controlled pivotal study. To evaluate whether P-15L (PearlMatrix TM P-15 Peptide Enhanced Bone Graft) is non-inferior in effectiveness to local autograft when applied in single level instrumented transforaminal lumbar interbody fusion (TLIF). P-15L, an FDA-designated Breakthrough Drug-Device, is a composite drug-device combination bone graft containing P-15, a 15-amino acid polypeptide, which enhances cell binding, proliferation, and differentiation resulting in bone formation. Skeletally mature patients, aged 22-80 years, with degenerative disc disease (DDD) were randomized 1:1 to P-15L (investigational) or to the local autograft (control) during single-level TLIF with a polyetheretherketone (PEEK) cage and supplemental pedicle screw fixation. The primary outcome was Composite Clinical Success (CCS) at 24 months, defined as: no index level secondary surgical procedures; achievement of fusion; ≥15-point improvement in Oswestry Low Back Pain Disability Questionnaire (ODI) from baseline; no new or worsening persistent neurological deficit relative to baseline; and no device-related serious adverse events (SAEs). 290 patients were enrolled at 33 sites: 141 (48.6%) received P-15L, and 149 (51.3%) received local autograft. P-15L was non-inferior ( P <0.0001) and superior ( P =0.002) to autograft with respect to CCS, with 55.5% of the investigational group achieving composite clinical success compared with 37.5% of the control group. P-15L had a 25.8% higher fusion rate as compared to autograft for the CCS at 24 months (84.3% vs. 58.5%, respectively). Device-related SAE rates were similar in both groups. P-15L was superior to local autograft in achieving clinical success at 24 months. Furthermore, P-15L produced a significantly higher fusion rate as compared to autograft. No meaningful clinical differences were found in the incidence of device-related SAEs. P-15L appears to be a safe and effective option for TLIF. 1.

Prospective, multicenter, single-blind, randomized, controlled pivotal study. Compare time-to-fusion in patients treated with P-15L (PearlMatrix TM P-15 Peptide Enhanced Bone Graft) versus local autograft over 24 months and evaluate changes in pain and quality of life at 24 months relative to baseline. P-15L, an FDA-designated Breakthrough Device, is a composite bone graft with P-15, a 15-amino acid polypeptide that promotes cellular adhesion, proliferation, and differentiation to support bone formation. Patients (22-80y) with degenerative disc disease were randomized to the investigational (P-15L) or control (local autograft) group during single-level transforaminal lumbar interbody fusion (TLIF) with a PEEK cage and supplemental pedicle screw fixation. Fusion assessments occurred at 6, 12, and 24 months. Time-to-fusion was tested for superiority as compared to the control using Kaplan-Meier survival analysis. Back and leg pain were measured using the Visual Analog Scale (VAS) and quality of life was assessed using the Short Form Survey (SF-12). The analysis included 290 patients from 33 sites; 141 (48.6%) received P-15L and 149 (51.3%) received local autograft. At randomization, at least 1 risk factor for pseudoarthrosis (obesity, nicotine use, or diabetes) was reported in 58.9% (83/141) of the investigational group and 60.4% (90/149) of the control group. More patients in the investigational than the control group achieved fusion at 6 months (Kaplan-Meier fusion rates 57.6% vs 26.9%, respectively), 12 months (68.8% vs 41.5%, respectively), and 24 months (81.1% vs 54.9%, respectively). P-15L was statistically superior to autograft for time-to-fusion (hazard ratio=1.87, 95% CI: 1.47, 2.38; P <0.0001). There was marked improvement in VAS and SF-12 relative to baseline in both groups at 24 months. P-15L promotes statistically superior earlier time-to-fusion than local autograft in instrumented TLIF. Both treatments resulted in clinically meaningful improvements in pain and quality of life at 24 months. 1.

This study aimed to evaluate the distance for the safe and efficient insertion of percutaneous pedicle screws (PPSs) in lumbar fixation surgery. On lumbar computed tomography thin-slice images parallel to the cranial vertebral endplate, two different insertion points of the PPS were defined: (1) the lateral wall of the pedicle (defined as the LP) and (2) the angle between the transverse process and superior articular process (TS). From these points, we measured the distance to the inner wall of the pedicle (A) and the posterior wall of the vertebral body (B). The distance was measured bilaterally from L1 to L5 of consecutive 60 patients. The results of PL-A (the mean distance ± standard deviation) from the L1 level to the L5 were 17.9 ± 3.0, 18.1 ± 2.9, 18.9 ± 3.1, 18.7 ± 3.4, and 19.9 ± 3.3mm, respectively. Those of PL-B were 24.1 ± 3.5, 23.2 ± 3.4, 23.0 ± 3.8, 22.1 ± 4.1, and 21.9 ± 3.8mm. The results of TS-A were 17.9 ± 2.6mm, 17.6 ± 2.2, 18.0 ± 2.3, 16.3 ± 2.2, and 17.1 ± 2.3, whereas those of TS-B were 22.8 ± 2.6mm, 21.6 ± 2.3, 21.2 ± 2.1, 18.6 ± 2.1, and 18.3 ± 2.2, respectively. Moreover, the PL-A, PL-B, TS-A, and TS-B of all L1-L5 were 18.7 ± 3.2, 22.9 ± 3.8, 17.4 ± 2.4, and 20.5 ± 2.9mm. This study can contribute to the safe and efficient insertion of the lumbar PPS.

Abstract.

Biomechanical optimization of pedicle screw trajectories in osteoporotic lumbar fusion: finite element analysis and validation of robotic-assisted implementation.

Background: Quantifying intraoperative nociceptive responses under general anesthesia remains challenging, particularly during complex procedures such as spinal surgery. The Nociception Level (NoL) index is a multiparametric tool designed to reflect the dynamic balance between nociception and analgesia in anesthetized patients. This study aimed to evaluate NoL fluctuations during predefined phases of spinal surgery and assess their relationship to anesthetic administration. Methods: This prospective observational study enrolled 44 adult patients undergoing lumbar discectomy, laminectomy, or spinal fusion under remifentanil-propofol anesthesia. Continuous NoL monitoring was performed using the PMD100™ system. Sixteen anatomically and procedurally defined surgical phases were analyzed. The primary outcome was the mean NoL value in each phase. The secondary outcome was the association between NoL values and intraoperative infusion rates of remifentanil and propofol. Repeated-measures ANOVA with Bonferroni correction was used for phase comparisons. Results: Mean NoL values remained within the target range (10-25) in most phases. However, significant elevations were observed during pedicle screw insertion (mean 27.9, SD ± 17.7), cage insertion (27.6, SD ± 10.5), and flavectomy (28.0, SD ± 27.0), indicating increased nociceptive burden. The lowest NoL values occurred during skin closure (16.6, SD ± 11.2) and discectomy (18.0, SD ± 2.8). Propofol and remifentanil infusion rates remained within standard clinical ranges but were slightly elevated during high-NoL phases. Conclusions: Despite standardized anesthesia, distinct nociceptive peaks were observed during specific stages of spinal surgery. These findings suggest that NoL monitoring may help identify high-nociception phases and guide tailored analgesic strategies. Future randomized trials are warranted to assess whether protocolized NoL-guided anesthesia improves intraoperative management and postoperative outcomes.

Retrospective cohort. To evaluate surgical outcomes and opioid consumption among patients undergoing a C3-T1 posterior cervical decompression and fusion (PCDF) with lateral mass or pedicle screw fixation at C7. Biomechanical work has suggested that junctional pedicle screws provide more robust fixation during cervicothoracic fixation at the expense of increased technical risk compared with lateral mass screws. However, minimal data exist directly comparing these 2 hardware options. Adult patients who underwent primary C3-T1 PCDF (2017-2022) with C7 lateral mass versus pedicle screw fixation were compared. Patient demographics, surgical characteristics, and surgical outcomes were collected. Outpatient opioid utilization and morphine milligram equivalents (MMEs) from 1-year preoperatively to 1-year postoperatively were obtained from Pennsylvania Prescription Drug Monitoring Program. In-hospital MME data were also collected. Thirty patients received lateral mass fixation, and 50 patients received pedicle screw fixation at C7. These groups were demographically similar, with similar average length of follow-up between the lateral mass (748±364d) and pedicle screw (853±402d, P=0.28) groups. Despite requiring a greater number of decompressed levels (4.17 vs. 3.74, P=0.002), cut-to-close time was shorter for the lateral mass group compared with the pedicle screw group (168±37.6 vs. 191±41.3min, P=0.015). However, both groups were similar regarding surgical outcomes and preoperative and 1-year postoperative opioid consumption. Despite a greater number of decompressed levels among the lateral mass group, these patients experienced a shorter average operative time during C3-T1 PCDF. However, short-term surgical outcomes and opioid consumption up to a year postoperatively were similar between groups. Thus, there does not appear to be short-term safety or pain drawbacks to C7 pedicle screws that would justify the decreased biomechanical advantages of lateral mass screws.