Alignment in motion: Fall risk in spine patients and the effect of vision, support surface, and adaptation on the cone of economy.

Background: Several assessment tools have been developed to estimate a patient's likelihood risk of falling. None of these measures estimate the contributions of the visual, vestibular, and somatosensory systems to fall risk, especially in patients with degenerative lumbar spine disease. Methods: Degenerative lumbar spine patients with radiculopathy (LD) and healthy subjects who were 35-70 years old without spine complaints were recruited. Patient reported outcome measures (PROMs) were collected prior to testing. Fall risk assessment was completed using Computer Dynamic Posturography (CDP), a computer-controlled balance machine that allows cone of economy (CoE) and cone of pressure (CoP) measurements. All patients completed Sensory Organization Tests (SOT) which include normal and perturbed stability, both with and without visual cues. Results: In total, 43 spine patients and 12 healthy controls were included, with mean age 57.8 years, 39.5% females, and mean BMI of 29.3 kg/m2. Nearly all CoE and most CoP dimensions were found to be larger in LD patients compared to controls across nearly all subtests (p<.05), with the largest dimensions generally observed in the surrounding and support sway testing condition. In LD patients, ODI and PROMIS Pain Interference were negatively correlated with CoE and CoP measurements (p<.05). Conclusions: In this prospective study, body sway was assessed as a function of CoE and CoP using the CDP system and was found to be elevated in spine patients, especially when they experienced increasing levels of visual and vestibular stimulation. The ability to identify the primary drivers of balance disorders is essential in spine patients and may be helpful in the development of a patient-specific treatment plan, which may in the future aid with fall-prevention initiatives.

Degenerative Spinal Stenosis and Ipsi-Contralateral Decompression: Presentation of a Surgical Technique and Clinical Cases.

Lumbar spinal stenosis is a widespread condition that significantly affects the quality of life in elderly individuals. Conservative therapy has a positive effect on patients whose primary symptom is pain. However, in severe cases with the presence of hypesthesia and paresis, surgical treatment comes into consideration. The aim of surgery is to decompress the neurovascular elements compressed by the narrowed spinal canal while preserving spinal stability. Conventional laminectomy, with or without fusion, has been considered effective for the treatment of this pathology, but its drawbacks are significant, including tissue trauma, secondary instability, and a substantial percentage of reoperations due to complications. In recent years, various minimally invasive spine surgery techniques have emerged, showing comparable results to laminectomy decompression in terms of relieving symptomatic spinal stenosis. Additionally, these techniques offer significant benefits such as minimal tissue trauma, reduced complication rates, and shorter operative time and recovery periods. Given the continuous development and improvement, minimally invasive surgery is expected to widely replace traditional open surgery for the treatment of lumbar stenosis in the future. In this article, we present our experience in the surgical treatment of patients with degenerative lumbar stenosis, detailing the technique of the minimally invasive procedure we utilize and highlighting some of the clinical cases in which it has been applied.

Impact of sarcopenia on outcomes following lumbar spine surgery for degenerative disease: an updated systematic review and meta-analysis.

PURPOSE: This study aimed to consolidate the evidence regarding the prognostic influence of sarcopenia in degenerative lumbar spine surgeries. METHODS: A literature search of public databases was conducted up to Nov 15, 2023 using combinations of the key words "sarcopenia" and "lumbar spine surgery". Eligible studies were those that focused on adults undergoing decompression or fusion surgery for degenerative lumbar spine diseases, and compared the outcomes between patients with and without preoperative sarcopenia. Primary outcomes were change in ODI and back and leg pain VAS pain scores. Secondary outcomes were changes in Eq. 5D, JOA, SFHS-p scores, and LOS. RESULTS: Ultimately, nine retrospective studies with a total of 993 patients were included. Sarcopenic patients exhibited significantly worse functional improvement as assessed by ODI compared to non-sarcopenic patients (pooled standardized mean difference [pSMD] = 0.53, 95% confidence interval [CI]: 0.17-0.90). Back pain (pSMD = 0.31, 95% CI:0.15-0.47) and leg pain (pSMD = 0.21, 95% CI:0.02 - 0.39) improvement were also less in sarcopenic patients. Non-sarcopenic patients had greater improvements in Eq. 5D (pSMD = 0.25) and SFHS-p (pSMD = 0.39), and shorter LOS (pSMD = 0.62). CONCLUSIONS: As compared to patients without sarcopenia, those with sarcopenia undergoing lumbar spine surgery for degenerative diseases have lower improvements in functional ability, quality of life, physical health, pain relief and extended hospitalization compared to those without sarcopenia.

Endoscopic Treatment of Lumbar Degenerative Disc Disease: A Narrative Review of Full-Endoscopic and Unilateral Biportal Endoscopic Spine Surgery.

BACKGROUND: Degenerative lumbar spine disease is the leading cause of disability and work absenteeism worldwide. Lumbar microdiscectomy became the standard treatment for herniated discs and stenotic disease. With the evolution of different techniques, endoscopic spinal surgery emerged to minimize the surgical footprint while providing at least non-inferior results. Currently, two different types of endoscopic spine procedures are dominating the surgical scenario: "Full-Endoscopic" (FE) and Unilateral Biportal Endoscopic" (UBE) Spine Surgery. The aim of this study is to describe and analyze their indications, their technical characteristicswithitsadvantagesanddisadvantagesofbothtechniquesandtheirfuture trends. METHODS: We performed a narrative review of the most relevant articles published up to August 2023 through a Pub Med search. The search terms " FE Spine Surgery" and " UBE Spine Surgery" were used. The articles selected, were independently reviewed by 3 authors and 55 full text articles were reviewed. RESULTS: The FE and UBE Spine Surgery techniques were described. The FE technique is performed with a monoportal access under constant saline irrigation. The FE comprises the transforaminal and the interlaminar approaches, and the indication depends from the pathology to treat, and still remains controversial. UBE can approach also the spine from a posterior, postero lateral,and para spinal route. It uses two different ports addressed to a target with continuous irrigation. The process of establishing these two portals is called triangulation. CONCLUSIONS: FE and UBE spine surgery have demonstrated outcomes comparable to open surgery, minimizing complications and surgical footprint.

Efficacy and Safety of Cortical Bone Trajectory Screws versus Pedicle Screws in Lumbar Fusion: A Systematic Review and Meta-Analysis.

OBJECTIVE: A systematic review and meta-analysis was conducted to compare the efficacy and safety of cortical bone trajectory (CBT) screws and traditional pedicle screws in lumbar fusion. METHODS: Randomized controlled studies and cohort studies on CBT versus pedicle screws in lumbar fusion were searched in China Biology Medicine, China National Knowledge Infrastructure, Wanfang, VIP Database for Chinese Technical and Science Periodicals, PubMed, Cochrane Library, and Web of Science databases. The search period spanned from the establishment of the databases to December 2023. The Cochrane bias risk assessment tool and Newcastle-Ottawa scale were applied to assess the quality of the literature included. Clinical and imaging data as well as surgical outcomes, recovery, and postoperative complications were extracted from the relevant literature. RESULTS: A total of 6 randomized controlled trials and 26 cohort studies were included after screening by inclusion and exclusion criteria with a total of 2478 patients. The meta-analysis demonstrated significant discrepancies between the CBT and TPS groups in Japanese Orthopaedic Association score at 3 and 6 months and final follow-up. Moreover, the TPS group exhibited a higher Oswestry disability index at final follow-up, a greater VAS for low back pain at both 1 week and final follow-up, as well as a higher VAS for leg pain at 1 month. Differences were also noted in surgical and recovery outcomes. However, there was no significant difference between the 2 groups in postoperative complications. CONCLUSIONS: CBT and TPS have analogous safety profiles when applied to lumbar fusion, but the clinical efficacy of CBT is superior to that of TPS to some extent, and the procedure is less invasive with faster recovery.

Virtual reality skateboarding training for balance and functional performance in degenerative lumbar spine disease.

BACKGROUND: Degenerative lumbar spine disease (DLD) is a prevalent condition in middle-aged and elderly individuals. DLD frequently results in pain, muscle weakness, and motor impairment, which affect postural stability and functional performance in daily activities. Simulated skateboarding training could enable patients with DLD to engage in exercise with less pain and focus on single-leg weight-bearing. The purpose of this study was to investigate the effects of virtual reality (VR) skateboarding training on balance and functional performance in patients with DLD. METHODS: Fourteen patients with DLD and 21 age-matched healthy individuals completed a 6-week program of VR skateboarding training. The motion capture and force platform systems were synchronized to collect data during a single-leg stance test (SLST). Musculoskeletal simulation was utilized to calculate muscle force based on the data. Four functional performance tests were conducted to evaluate the improvement after the training. A Visual Analogue Scale (VAS) was also employed for pain assessment. RESULTS: After the training, pain intensity significantly decreased in patients with DLD (p = 0.024). Before the training, patients with DLD took longer than healthy individuals on the five times sit-to-stand test (p = 0.024). After the training, no significant between-group differences were observed in any of the functional performance tests (p > 0.05). In balance, patients with DLD were similar to healthy individuals after the training, except that the mean frequency (p = 0.014) was higher. Patients with DLD initially had higher biceps femoris force demands (p = 0.028) but shifted to increased gluteus maximus demand after the training (p = 0.037). Gluteus medius strength significantly improved in patients with DLD (p = 0.039), while healthy individuals showed consistent muscle force (p > 0.05). CONCLUSION: This is the first study to apply the novel VR skateboarding training to patients with DLD. VR skateboarding training enabled patients with DLD to achieve the training effects in a posture that relieves lumbar spine pressure. The results also emphasized the significant benefits to patients with DLD, such as reduced pain, enhanced balance, and improved muscle performance.

Pain outcome of non-instrumented lumbar decompressive surgery for degenerative lumbar spine disease using patient-reported pain outcome instruments.

Objectives: A clinical disorder known as degenerative lumbar spine disease (DLSD) is characterized by persistent low back pain (LBP) coupled with radiculopathy and other signs of neurologic impairment. Using patient-reported pain outcome assessment tools, this study evaluated the pain outcome of non-instrumented lumbar decompressive surgery for DLSD. Materials and Methods: A prospective longitudinal research was conducted. Using the metric visual analog scale (VAS) score and the Oswestry disability index (ODI), consenting patients who underwent non-instrumented lumbar decompressive surgery for symptomatic DLSD were evaluated for radicular pain and LBP. The evaluation was conducted both immediately before surgery and 6 months after surgery. Data generated by comparing the pre-operative and post-operative VAS and ODI scores were then analyzed using descriptive and inferential statistics. Results: Sixty-seven patients in total completed the study. Thirty-six (54%) males and 31 (46%) females, with a mean age and body mass index of 55.28 years and 29.5 k/m2, respectively. At 6 months postoperatively, there was significant pain reduction from the pre-operative baseline VAS for LBP (67.12-32.74) with P < 0.001, VAS for radicular pain (75.39-32.75) with P < 0.001, and ODI (65.30-27.66) with P < 0.001. There was a greater decrease in radicular pain than in LBP following lumbar decompressive only surgery (P = 0.03). Conclusion: Patients with symptomatic DLSD and high pre-operative back pain scores without considerable listhesis should anticipate a significant reduction in radicular and back pain intensity, as well as pain-related functional disability, 6 months after non-instrumented lumbar decompressive surgery.

Percutaneous removal and replacement of a novel percutaneous interspinous device.

Objective: The aim of this study is to explain the technique used for removing and replacing a novel percutaneous interspinous device (PID).Procedure: Three male patients, with a mean age of 66 years (range 62-72), were included in the study due to displacement (N = 2) or misplacement (N = 1) of the novel PID. This occurred after a mean of 23.3 ± 10.5 days from the initial placement (range 13-34) at the L4-L5 level (N = 1) and L3-L4 level (N = 2). Following the removal of the PID, four new devices were implanted.Conclusion: The novel PID can be safely removed either immediately after its placement during the procedure or after a certain period of days or months from its implantation. The removal procedure can be performed percutaneously under imaging guidance, by closing the four retractable wings, using the same instrumentation as utilized during the initial implantation.

Comparative Analysis of Early and Long-Term Outcomes of Patients with Degenerative Lumbar Spine Disease Using the DIAM Stabilizer and Standard Rehabilitation Program: A Preliminary Prospective Randomized Controlled Trial with 1-Year Follow-Up.

Low back pain (LBP) is a leading cause of disability and work absenteeism. The cause of LBP may be degeneration of the intervertebral disc. LBP is characterized by considerable variability and tends to develop into chronic pain. Treatment of LBP includes conservative and rehabilitative treatments, surgery, and so-called minimally invasive treatment. One of the most commonly performed procedures is interspinous stabilization using a dynamic interspinous DIAM (device for intervertebral assisted motion) stabilizer. There is still no clear, strong evidence for the effectiveness and superiority of surgical treatment over conservative treatment. This study aimed to compare the early and long-term outcomes of patients with LBP using the DIAM interspinous stabilizer in relation to patients treated conservatively. A group of 86 patients was prospectively randomized into two comparison groups: A (n = 43), treated with the DIAM dynamic stabilizer for degenerative lumbar spine disease (mean age = 43.4 years ± SD = 10.8 years), and B (n = 43), treated conservatively. Pain severity was assessed using the visual analog scale (VAS), whereas disability was assessed using the Oswestry disability index (ODI). The difference in preoperative and postoperative ODI scores ≥ 15 points was used as a criterion for treatment effectiveness, and the difference in VAS scores ≥ 1 point was used as a criterion for pain reduction. In patients under general anesthesia, the procedure only included implantation of the DIAM system. Patients in the control group underwent conservative treatment, which included rehabilitation, a bed regimen, analgesic drug treatment and periarticular spinal injections of anti-inflammatory drugs. It was found that all patients (n = 43) continued to experience LBP after DIAM implantation (mean VAS score of 4.2). Of the 36 patients who experienced LBP with sciatica before the procedure, 80.5% (n = 29) experienced a reduction in pain. As for the level of fitness, the average ODI score was 19.3 ± 10.3 points. As for the difference in ODI scores in the pre-treatment results vs. after treatment, the average score was 9.1 ± 10.6. None of the patients required reoperation at 12 months after surgery. There were no statistically significant differences between the two groups in either early (p = 0.45) or long-term outcomes (p = 0.37). In conclusion, neurosurgical treatment with the DIAM interspinous stabilizer was as effective as conservative treatment and rehabilitation during the one-year follow-up period.

Carbon Fiber-Reinforced PolyEtherEtherKetone (CFR-PEEK) Instrumentation in Degenerative Disease of Lumbar Spine: A Pilot Study.

CFR-PEEK is gaining popularity in spinal oncological applications due to its reduction of imaging artifacts and radiation scattering compared with titanium, which allows for better oncological follow-up and efficacy of radiotherapy. We evaluated the use of these materials for the treatment of lumbar degenerative diseases (DDs) and considered the biomechanical potential of the carbon fiber in relation to its modulus of elasticity being similar to that of bone. Twenty-eight patients with DDs were treated using CRF-PEEK instrumentation. The clinical and radiographic outcomes were collected at a 12-month FU. Spinal fusion was evaluated in the CT scans using Brantigan scores, while the clinical outcomes were evaluated using VAS, SF-12, and EQ-5D scores. Out of the patients evaluated at the 12-month FU, 89% showed complete or almost certain fusion (Brantigan score D and E) and presented a significant improvement in all clinical parameters; the patients also presented VAS scores ranging from 6.81 ± 2.01 to 0.85 ± 1.32, EQ-5D scores ranging from 53.4 ± 19.3 to 85.0 ± 13.7, SF-12 physical component scores (PCSs) ranging from 29.35 ± 7.04 to 51.36 ± 9.75, and SF-12 mental component scores (MCSs) ranging from 39.89 ± 11.70 to 53.24 ± 9.24. No mechanical complications related to the implant were detected, and the patients reported a better tolerance of the instrumentation compared with titanium. No other series of patients affected by DD that was stabilized using carbon fiber implants have been reported in the literature. The results of this pilot study indicate the efficacy and safety of these implants and support their use also for spinal degenerative diseases.

Lumbar Facet Joint Fluid: A Reliable Sign of Lumbar Instability.

Lumbar degenerative spondylolisthesis (LDS) is a prevalent condition among the elderly population. Magnetic resonance imaging (MRI) is often the first investigative modality if indicated clinically. However, the standard supine position used during an MRI may fail to detect dynamic instability. In such cases, the presence of facet joint fluid is a reliable sign, and further investigation, such as stress radiographs, should be conducted to confirm dynamic instability. Here, we present a typical case demonstrating the importance of this finding. A patient presented with neurological claudication, and an MRI was initially unremarkable except for the presence of lumbar facet joint fluid. This finding prompted us to conduct stress radiographs, which eventually confirmed dynamic instability.

Full Endoscopic Lumbar Stenosis Decompression: A Future Gold Standard in Managing Degenerative Lumbar Canal Stenosis.

BACKGROUND: Until recently, open decompression was considered the gold standard for the management of spinal stenosis, but the evolution of minimally invasive spine instruments has brought a new dimension to the management of spinal stenosis. Full endoscopic surgery has a lot of advantages in terms of minimal soft tissue damage, less bleeding, shorter hospital length of stay, and earlier return to work. Our aim was to evaluate the efficacy of full endoscopic lumbar decompression for degenerative lumbar canal stenosis compared with classic open decompression surgery. METHODS: This is a retrospective cohort study of degenerative lumbar spinal stenosis without instability, consisting of 132 open decompression and 163 full endoscopic decompression patients. We evaluated the clinical result of the pre- and postoperative visual analog scale (VAS) of leg pain, back pain, and Oswestry Disability Index (ODI). We observed the patients until 1 year after the operation. RESULTS: The postoperative ODI scores and VAS scores for back pain and leg pain were better than the preoperative scores. The ODI scores and VAS scores for leg pain were significantly better in both groups (P = 0.033 and 0.04, respectively). The main difference between open and full endoscopic decompression was the VAS back pain and amount of bleeding. In the full endoscopic group, the mean VAS back pain was 1.6 and the amount of bleeding was minimal. In the open decompression surgery, the mean VAS back pain was 3.5 and the amount of bleeding was around 84 mL. The length of hospital stay was shorter in the full endoscopic group, which was 1.5 days compared with 3.4 days in open decompression (P = 0.034). CONCLUSION: Full endoscopic decompression showed better early results compared with the conventional group, but a long-term study is still needed for further evaluation of the clinical results. The use of the full endoscopic technique is very promising in the management of spinal stenosis. CLINICAL RELEVANCE: This study provides a comparison of the efficacy of open decompression and full endoscopic decompression in degenerative lumbar canal stenosis.

Use of Artificial Intelligence for the Development of Predictive Model to Help in Decision-Making for Patients with Degenerative Lumbar Spine Disease.

Context The aim of the study was to develop a prognostic model using artificial intelligence for patients undergoing lumbar spine surgery for degenerative spine disease for change in pain, functional status, and patient satisfaction based on preoperative variables included in following categories-sociodemographic, clinical, and radiological. Methods and Materials A prospective cohort of 180 patients with lumbar degenerative spine disease was included and divided into three classes of management-conservative, decompressive surgery, and decompression with fixation. Preoperative variables, change in outcome measures (visual analog scale-VAS, Modified Oswestry Disability Index-MODI, and Neurogenic Claudication Outcome Score-NCOS), and type of management were assessed using Machine Learning models. These were used for creating a predictive tool for deciding the type of management that a patient should undergo to achieve the best results. Multivariate logistic regression was also used to identify prognostic factors of significance. Results The area under the curve (AUC) was calculated from the receiver-operating characteristic (ROC) analysis to evaluate the discrimination capability of various machine learning models. Random Forest Classifier gave the best ROC-AUC score in all three classes (0.863 for VAS, 0.831 for MODI, and 0.869 for NCOS), and the macroaverage AUC score was found to be 0.842 suggesting moderate discriminatory power. A graphical user interface (GUI) tool was built using the machine learning algorithm thus defined to take input details of patients and predict change in outcome measures. Conclusion This study demonstrates that machine learning can be used as a tool to help tailor the decision-making process for a patient to achieve the best outcome. The GUI tool helps to incorporate the study results into active decision-making.

Biomechanical effects of interbody cage height on adjacent segments in patients with lumbar degeneration: a 3D finite element study.

OBJECTIVE: To investigate the biomechanical effects of interbody cage height on adjacent segments in patients with lumbar degeneration undergoing transforaminal lumbar interbody fusion (TLIF) surgery, so as to provide references for selection of interbody cage. METHODS: The finite element model of normal lower lumbar spine (L3-S1) was built and validated, then constructed three different degenerative segments in L3-L4, and the cages with different height (8, 10, 12, 14 mm) were implanted into L4-L5 disc. All the twelve models were loaded with pure moment of 7.5 N m to produce flexion, extension, lateral bending and axial rotation motions on lumbar spine, and the effects of cage height on range of motion (RoM) and intervertebral pressure in lumbar spine were investigated. RESULTS: The RoM of adjacent segments and the maximum stress of intervertebral discs increased with the increase in cage height, but this trend was not obvious in mild and moderate degeneration groups. After implantation of four different height cages (8, 10, 12, 14 mm), the RoM of L3/L4 segment reached the maximum during extension. The RoM of mild degeneration group was 2.07°, 2.45°, 2.48°, 2.54°, that of moderate degeneration group was 1.79°, 1.97°, 2.05°, 2.05°, and that of severe degeneration group was 1.43°, 1.66°, 1.74°, 1.74°. The stress of L3-L4 intervertebral disc reached the maximum during flexion. The maximum stress of L3-L4 intervertebral disc was 20.16 MPa, 20.28 MPa, 20.31 MPa and 20.33 MPa in the mild group, 20.58 MPa, 20.66 MPa, 20.71 MPa and 20.75 MPa in the moderate group, and 21.27 MPa, 21.40 MPa, 21.50 MPa and 21.60 MPa in the severe group. CONCLUSION: For patients with mild-to-moderate lumbar degenerative disease who need to undergo TLIF surgery, it is recommended that the height of fusion cage should not exceed the original intervertebral space height by 2 mm, while for patients with severe degeneration, a fusion cage close to the original intervertebral height should be selected as far as possible, and the intervertebral space should not be overstretched.

Oblique lateral interbody fusion combined with different internal fixations for the treatment of degenerative lumbar spine disease: a finite element analysis.

BACKGROUND: Little is known about the biomechanical performance of different internal fixations in oblique lumbar interbody fusion (OLIF). Here, finite element (FE) analysis was used to describe the biomechanics of various internal fixations and compare and explore the stability of each fixation. METHODS: CT scans of a patient with lumbar degenerative disease were performed, and the l3-S1 model was constructed using relevant software. The other five FE models were constructed by simulating the model operation and adding different related implants, including (1) an intact model, (2) a stand-alone (SA) model with no instrument, (3) a unilateral pedicle screw model (UPS), (4) a unilateral pedicle screw contralateral translaminar facet screw model (UPS-CTFS), (5) a bilateral pedicle screw (BPS) model, and (6) a cortical bone trajectory screw model (CBT). Various motion loads were set by FE software to simulate lumbar vertebral activity. The software was also used to extract the range of motion (ROM) of the surgical segment, CAGE and fixation stress in the different models. RESULTS: The SA group had the greatest ROM and CAGE stress. The ROM of the BPS and UPS-CTFS was not significantly different among motion loadings. Compared with the other three models, the BPS model had lower internal fixation stress among loading conditions, and the CBT screw internal fixation had the highest stress among loads. CONCLUSIONS: The BPS model provided the best biomechanical stability for OLIF. The SA model was relatively less stable. The UPS-CTFS group had reduced ROM in the fusion segments, but the stresses on the internal fixation and CAGE were relatively higher in the than in the BPS group; the CBT group had a lower flexion and extension ROM and higher rotation and lateral flexion ROM than the BPS group. The stability of the CBT group was poorer than that of the BPS and LPS-CTFS groups. The CAGE and internal fixation stress was greater in the CBT group.

The impact of interbody approach and lumbar level on segmental, adjacent, and sagittal alignment in degenerative lumbar pathology: a radiographic analysis six months following surgery.

BACKGROUND CONTEXT: Interbody fusion, including: transforaminal (TLIF), posterior (PLIF), anterior (ALIF), and lateral (LLIF); effectively treat lumbar degenerative pathology and provide spinopelvic balance. Although the decision on surgical approach and technique are multifactorial and patient specific, the impact of the interbody approach on segmental and adjacent level lordosis could be an important factor to consider during pre-operative planning to achieve pre-specified alignment goals. PURPOSE: The purpose of this study is to compare the 6-month postoperative radiographic outcomes in the lumbar spine following 1 to 2 level transforaminal (TLIF), posterior (PLIF), anterior (ALIF), and lateral (LLIF) interbody fusions at the L3-4, L4-5, and L5-S1 levels. As our primary outcome, we evaluated the change in segmental lordosis at the level of fusion in ALIF/LLIF approaches compared to TLIF/PLIF. Secondarily, we evaluated the pelvic incidence to lumbar lordosis (PI-LL) mismatch and examined the compensatory lordotic changes at the adjacent levels 6 months following surgery. STUDY DESIGN: Retrospective cohort. PATIENT SAMPLE: This retrospective study included 18 centers of various practice settings across the United States. Patients were included in the study if they underwent a one- or two-level primary lumbar fusion for degenerative pathology. OUTCOMES MEASURES: Measurements of the pre-operative and 6-month post-operative lumbar AP and lateral lumbar plain radiographs included: pelvic incidence (PI), pelvic tilt, lumbar lordosis from L1-S1 (LL), as well as segmental lordosis (SL) of each segment between L1-S1. METHODS: Due to there being 2 evaluated time points, patients were then grouped based on alignment into categories of preserved, restored, not corrected, and worsened. RESULTS: 474 patients underwent 608 levels of fusion. ALIF/LLIF resulted in significantly more segmental lordosis compared to TLIF/PLIF procedures at both L4-5 and L5-S1 (p<.001). Overall, ALIF/LLIF resulted in significantly more global lumbar lordotic alignment change compared to TLIF/PLIF (p=.01). Whether patients' alignment was preserved versus worsened was not significantly predicted by type of procedure. Similarly, whether patients' alignment was restored versus not corrected was not significantly predicted by type of procedure. Finally, anterior approaches resulted in decreased lordosis at adjacent levels, thus resulting in a more neutral position. CONCLUSION: In this large multicenter retrospective study of 1 to 2 level interbody fusion surgeries, we identified that A/LLIF procedures at L4-L5 and L5-S1 resulted in greater segmental lordosis restoration and PI-LL mismatch improvement compared to T/PLIF procedures. A/LLIF may also significantly reduce lordosis (compared to T/PLIF) at the adjacent levels in a fashion that serves to reduce the lumbar lordosis that may have been increased at the fused level.

A pilot study of endoscope-assisted MITLIF with fluoroscopy-guided technique: intraoperative objective and subjective evaluation of disc space preparation.

BACKGROUND: Adequate discectomy and endplate preparation are extremely crucial steps for spinal interbody fusion. Minimally invasive transforaminal lumbar interbody fusion MITLIF technique is safe and effective. However, concerns exist regarding sufficient disc space preparation from unilateral access. The purpose of this study, was to demonstrate our preliminary experience in objective and subjective evaluation of disc space preparation intraoperatively during endoscope-assisted MITLIF with fluoroscopy-guided, describing some of its possible advantages, and analyzing its safety and feasibility. METHODS: From March 2018 to July 2019, three patients with degenerative spinal stenosis with radiculopathy and instability underwent endoscope-assisted MITLIF with fluoroscopy-guided. Patients' demographic data, clinical parameters, subsidence, and fusion were collected. RESULTS: Patients were successfully treated by endoscope-assisted MITLIF with fluoroscopy-guided at single-level or two-level. Symptoms improved postoperatively in all patients, and no complications occurred during follow-up. No cage subsidence was observed. At 6-month postoperatively, there was bony fusion observed on computed tomography in two patients. CONCLUSION: Endoscope-assisted MITLIF with fluoroscopy-guided is a safe and feasible technique to improve visualization during discectomy and endplate preparation objectively and subjectively, possibly increasing fusion rate and early time to fusion.

Case of lumbar ligamentum flavum hematoma with epidural hematoma resulting in cauda equina compression.

Background: Lumbar ligamentum flavum hematomas (LFHs) are rare. However, when they occur and contribute to epidural cauda equina compression, timely surgical intervention is frequently warranted. Case Description: A 69-year-old female presented with the left lower extremity sciatica and gait disturbance of 2 weeks' duration that ultimately evolved into a paraparesis/cauda equina syndrome. When the lumbar MRI revealed left-sided L4-L5 epidural compression attributed to a hemorrhage into the hypertrophied ligamentum flavum (HLF), she successfully underwent a bilateral fenestration/decompressive procedure. Pathologically, neovascularization and rupture of the ventral layers of the degenerated and thickened HLF contributed to the LFH. Conclusion: Arterial neovascularization (i.e., arterial feeding vessels from paramuscular/prelaminar lumbar branches) contributed to a left-sided L4-L5 LFH that resulted in epidural cauda equina compression in a 69-year-old female. Following surgical focal fenestration/decompression, the patient's symptoms/signs resolved.

[Reasons analysis on unplanned reoperation of degenerative lumbar spine diseases].

OBJECTIVE: To review the research on the reasons of unplanned reoperation (URP) for degenerative lumbar spine diseases, and to provide new ideas for improving the quality of surgery for degenerative lumbar spine diseases. METHODS: The literature about the URP of degenerative lumbar spine diseases at home and abroad in recent years was reviewed and analyzed. RESULTS: At present, the reasons for URP include surgical site infection (SSI), hematoma formation, cerebrospinal fluid leakage (CSFL), poor results of surgery, and implant complications. SSI and hematoma formation are the most common causes of URP, which happen in a short time after surgery; CSFL also occurs shortly after surgery but is relatively rare. Poor surgical results and implant complications occurred for a long time after surgery. Factors such as primary disease and surgical procedures have an important impact on the incidence of URP. CONCLUSION: The main reasons for URP are different in various periods after lumbar spine surgery. Interventions should be given to patients with high-risk URP, which thus can reduce the incidence of URP and improve the surgery quality and patients' satisfaction.

Role of psychosocial factors on the effect of physical activity on physical function in patients after lumbar spine surgery.

BACKGROUND: The purpose of this study was to investigate the longitudinal postoperative relationship between physical activity, psychosocial factors, and physical function in patients undergoing lumbar spine surgery. METHODS: We enrolled 248 participants undergoing surgery for a degenerative lumbar spine condition. Physical activity was measured using a triaxial accelerometer (Actigraph GT3X) at 6-weeks (6wk), 6-months (6M), 12-months (12M) and 24-months (24M) following spine surgery. Physical function (computerized adaptive test domain version of Patient-Reported Outcomes Measurement Information System) and psychosocial factors (pain self-efficacy, depression and fear of movement) were assessed at preoperative visit and 6wk, 6M, 12M and 24M after surgery. Structural equation modeling (SEM) techniques were utilized to analyze data, and results are represented as standardized regression weights (SRW). Overall SRW were computed across five imputed datasets to account for missing data. The mediation effect of each psychosocial factor on the effect of physical activity on physical function were computed [(SRW for effect of activity on psychosocial factor X SRW for effect of psychosocial factor on function) ÷ SRW for effect of activity on function]. Each SEM model was tested for model fit by assessing established fit indexes. RESULTS: The overall effect of steps per day on physical function (SRW ranged from 0.08 to 0.19, p<0.05) was stronger compared to the overall effect of physical function on steps per day (SRW ranged from non-existent to 0.14, p<0.01 to 0.3). The effect of steps per day on physical function and function on steps per day remained consistent after accounting for psychosocial factors in each of the mediation models. Depression and fear of movement at 6M mediated 3.4% and 5.4% of the effect of steps per day at 6wk on physical function at 12M, respectively. Pain self-efficacy was not a statistically significant mediator. CONCLUSIONS: The findings of this study suggest that the relationship between physical activity and physical function is stronger than the relationship of function to activity. However, future research is needed to examine whether promoting physical activity during the early postoperative period may result in improvement of long-term physical function. Since depression and fear of movement had a very small mediating effect, additional work is needed to investigate other potential mediating factors such as pain catastrophizing, resilience and exercise self-efficacy.