Incidence Of Adjacent Segment Disease Research Articles

Revision Surgery Rates Following Transforaminal Lumbar Interbody Fusion in Patients with and without Osteoporosis.

Osteoporosis is becoming increasingly prevalent in the spine surgery population and has been shown to be associated with surgical failure in spinal deformity operations. Little is known about the impact of osteoporosis on radiographic and surgical complications following degenerative fusion techniques. To compare complications and radiographic alignment in osteoporotic versus non-osteoporotic patients undergoing transforaminal lumbar interbody fusion (TLIF). Retrospective cohort study. A total of 78 patients, 39 with osteoporosis and 39 without osteoporosis, were included in this study. The following data were observed for all cases: patient demographics, radiographic alignment, and complications. Adult patients with two-year follow-up who underwent transforaminal lumbar interbody fusion (TLIF) at a single academic institution were identified. Eligible patients were propensity matched by the presence of osteoporosis while accounting for age, sex, and BMI. Patient demographics, procedural characteristics, preoperative to two-year postoperative change in spinopelvic alignment, and complications were compared. Multivariate regression analyses, accounting for age, gender, and Charlson Comorbidity Index (CCI), were performed to evaluate outcomes following TLIF. In total, 78 patients with complete data were included with a mean age of 63.28, 70.51% were female, mean CCI was 1.02 and mean clinical follow up was 33.3 months. At two years postoperatively, osteoporosis patients had a significantly greater increase in PI-LL from pre-operation (6.55° vs -0.02°, p=0.010). In addition, while there was no statistically significant difference in medical and surgical complication (all p>0.05), osteoporosis patients were 2.8 times more likely to develop adjacent segment diseases (p=0.05). Additionally, over 30% of patients with osteoporosis underwent revision and osteoporotic patients were 9.2 times more likely to undergo revision (p=0.008) than patients without osteoporosis, most commonly for adjacent segment disease. In this single-center multi-surgeon study, osteoporotic patients experienced significant worsening of PI-LL mismatch postoperatively and had a higher incidence of adjacent segment disease and revision. Although TLIF remains an important procedure in osteoporotic patients, increased care should be taken to optimize bone quality in the perioperative period to avoid potential mechanical and surgical complications.

Efficacy of Anterior Cervical Discectomy and Fusion Versus Cervical Disc Arthroplasty in the Treatment of Cervical Degenerative Disc Disease, Radiculopathy, and Myelopathy: A Systematic Review.

Cervical degenerative disc disease (DDD) is a condition in which the discs in the neck deteriorate, causing symptoms including neck and arm pain, muscle weakness, and incoordination. In severe cases, it can lead to nerve and spinal cord compression, resulting in radiculopathy and myelopathy. This review aimed to assess the effectiveness of two surgical treatments, anterior cervical discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA), for addressing cervical DDD, radiculopathy, and myelopathy. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a literature search was conducted in the PubMed and BioMed Central databases, from January to March 2024. Thirty-one studies were included, comparing the outcomes of ACDF and CDA in patients with cervical DDD, radiculopathy, and myelopathy. Data were analyzed to evaluate outcomes such as the Neck Disability Index (NDI), pain levels, neurological status, incidence of secondary surgeries, range of motion (ROM) maintenance, and occurrence of adjacent segment disease. CDA demonstrated comparable or superior clinical success to ACDF. Both the techniques showed similar improvements in NDI, pain levels, and neurological status during medium- and long-term follow-ups. CDA had lower rates of secondary surgeries and adverse events related to surgery or implants compared to ACDF. It also demonstrated a lower incidence of adjacent segment disease and better ROM preservation. The evidence supports CDA as a safe and effective alternative to ACDF for patients with cervical DDD, particularly those who may benefit from motion preservation. However, further long-term, multicenter randomized controlled trials are needed to provide more definitive guidance for clinical practice.

Lumbar Arthroplasty is Associated With a Lower Incidence of Adjacent Segment Disease Compared With ALIF.

Lumbar Arthroplasty is Associated With a Lower Incidence of Adjacent Segment Disease Compared With ALIF.

A systematic review of risk factors and adverse outcomes associated with anterior cervical discectomy and fusion surgery over the past decade.

Anterior cervical discectomy and fusion (ACDF) is one of the most frequently performed cervical surgeries in the world, yet there have been several reported complications. To determine the actual incidence of complications related to ACDF as well as any risk variables that may have been identified in earlier research. To evaluate the origin, presentation, natural history, and management of the risks and the complications, we conducted a thorough assessment of the pertinent literature. An evaluation of clinical trials and case studies of patients who experienced one or more complications following ACDF surgery was done using a PubMed, Cochrane Library, and Google Scholar search. Studies involving adult human subjects that were written in the English language and published between 2012 and 2022 were included in the search. The search yielded 79 studies meeting our criteria. The overall rates of complications were as follows: Dysphagia 7.9%, psudarthrosis 5.8%, adjacent segment disease (ASD) 8.8%, esophageal perforations (EPs) 0.5%, graft or hardware failure 2.2%, infection 0.3%, recurrent laryngeal nerve palsy 1.7%, cerebrospinal fluid leak 0.8%, Horner syndrome 0.5%, hematoma 0.8%, and C5 palsy 1.9%. Results showed that dysphagia was a common postoperative sequelae with bone morphogenetic protein use and a higher number of surgical levels being the major risk factors. Pseudarthrosis rates varied depending on the factors such as asymptomatic radiographic graft sinking, neck pain, or radiculopathy necessitating revision surgery. The incidence of ASD indicated no data to support anterior cervical plating as more effective than standalone ACDF. EP was rare but frequently fatal, with no correlation found between patient age, sex, body mass index, operation time, or number of levels.

466 Primary Anterior Lumbar Interbody Fusion, With and Without Posterior Instrumentation: A 1377 Patient Cohort From a Multicenter Spine Registry

INTRODUCTION: Anterior lumbar interbody fusion (ALIF) is a versatile and powerful technique for a variety of lumbar degenerative pathologies. Adding posterior supplementary fixation to ALIF (ALIF+PSF) is common and may confer benefits in terms of higher fusion rate but could contribute to adjacent segment disease (ASD) due to additional rigidity. METHODS: Adult patients who underwent primary ALIF for lumbar degenerative pathology between levels L4-S1 over a 12-year period were included. Cases of trauma, cancer, infection, supplemental decompression, noncontiguous fusions, prior lumbar fusions, and other interbody devices were excluded. Primary outcomes included reoperation for nonunion and ASD. Multivariable Cox proportional hazard regression was used to evaluate risks adjusting for patient characteristics. RESULTS: The study consisted of 1377 cases; 307 ALIF alone and 1070 ALIF+PSF. Mean follow-up time was 5.6-years. 5-year crude nonunion incidence was 2.4% for ALIF only and 0.5% for ALIF+PSF; after adjustment for covariates, a lower operative nonunion risk was observed for ALIF+PSF (HR = 0.22, 95% CI = 0.07-0.70). Of patients deemed potentially suitable for ALIF alone, one would need to add PSF in 53-patients to prevent one case of operative nonunion at a 5-year follow-up (number needed to treat). Five-year operative ASD incidence was 4.3% for ALIF only and 6.2% for ALIF+PSF; with adjustments, no difference was observed between the cohorts (HR = 0.96, 95% CI = 0.53-1.74). CONCLUSIONS: While addition of posterior instrumentation in ALIFs is associated with lower risk of operative nonunion compared to ALIF alone, it is rare in both techniques (<5%). Accordingly, surgeons should evaluate added risks associated with addition of PSF, and rather reserve PSF for patients at higher risk for operative nonunion. Rates of operative ASD were not statistically higher with addition of PSF suggesting concern regarding future ASD may be less supported.

Are there differences in the reoperation rates for operative adjacent-segment disease between ALIF+PS, PLIF+PS, TLIF+PS, and LLIF+PS? An analysis of a cohort of 5291 patients.

Biomechanical factors in lumbar fusions accelerate the development of adjacent-segment disease (ASD). Stiffness in the fused segment increases motion in the adjacent levels, resulting in ASD. The objective of this study was to determine if there are differences in the reoperation rates for symptomatic ASD (operative ASD) between anterior lumbar interbody fusion plus pedicle screws (ALIF+PS), posterior lumbar interbody fusion plus pedicle screws (PLIF+PS), transforaminal lumbar interbody fusion plus pedicle screws (TLIF+PS), and lateral lumbar interbody fusion plus pedicle screws (LLIF+PS). A retrospective study using data from the Kaiser Permanente Spine Registry identified an adult cohort (≥ 18 years old) with degenerative disc disease who underwent primary lumbar interbody fusions with pedicle screws between L3 to S1. Demographic and operative data were obtained from the registry, and chart review was used to document operative ASD. Patients were followed until operative ASD, membership termination, the end of study (March 31, 2022), or death. Operative ASD was analyzed using Cox proportional hazards models. The final study population included 5291 patients with a mean ± SD age of 60.1 ± 12.1 years and a follow-up of 6.3 ± 3.8 years. There was a total of 443 operative ASD cases, with an overall incidence rate of reoperation for ASD of 8.37% (95% CI 7.6-9.2). The crude incidence of operative ASD at 5 years was the lowest in the ALIF+PS cohort (7.7%, 95% CI 6.3-9.4). In the adjusted models, the authors failed to detect a statistical difference in operative ASD between ALIF+PS (reference) versus PLIF+PS (HR 1.06 [0.79-1.44], p = 0.69) versus TLIF+PS (HR 1.03 [0.81-1.31], p = 0.83) versus LLIF+PS (HR 1.38 [0.77-2.46], p = 0.28). In a large cohort of over 5000 patients with an average follow-up of > 6 years, the authors found no differences in the reoperation rates for symptomatic ASD (operative ASD) between ALIF+PS and PLIF+PS, TLIF+PS, or LLIF+PS.

Complications With Demineralized Bone Matrix, Hydroxyapatite and Beta-Tricalcium Phosphate in Single and Two-Level Anterior Cervical Discectomy and Fusion Surgery.

Systematic literature review. To analyze the evidence available reporting complications in single or two-level anterior cervical discectomy and fusion (ACDF) using a demineralized bone matrix (DBM), hydroxyapatite (HA), or beta-tricalcium phosphate (β-TCP). A systematic review of the literature using PubMed, EMBASE, Cochrane Library, and ClinicalTrials.gov databases was performed in August 2020 to identify studies reporting complications in one or two-level ACDF surgery using DBM, HA, or β-TCP. The study was reported following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. A total of 1857 patients were included, 981 male and 876 female, across 17 articles; 5 prospective, and 12 retrospectives. We noted heterogeneity among the included studies concerning the study design and combination of graft materials utilized in them. However, we noted a higher incidence of adjacent segment disease (17.7%) and pseudoarthrosis (9.3%) in fusion constructs using DBM. Studies using β-TCP reported a higher incidence of pseudoarthrosis (28.2%) and implant failures (17.9%). Degenerative cervical conditions treated with one or two-level ACDF surgery using DBM, HA, or β-TCP with or without cervical plating are associated with complications such as adjacent segment disease, dysphagia, and pseudarthrosis. However, consequent to the study designs and clinical heterogeneity of the studies, it is not possible to correlate these complications accurately with any specific graft material employed. Further well-designed prospective studies are needed to correctly know the related morbidity of each graft used for achieving fusion in ACDF.

Validation of age-adjusted pelvic incidence minus lumbar lordosis and lordosis distribution index for assessing adjacent-segment disease after short-level lumbar fusion surgery: minimum 5 years of follow-up.

The purpose of this study was to investigate the influence of sagittal alignment according to age-adjusted pelvic incidence minus lumbar lordosis (PI-LL) and lordosis distribution index (LDI) on the occurrence of adjacent-segment disease (ASD) after lumbar fusion surgery. This study retrospectively reviewed 234 consecutive patients with lumbar degenerative diseases who underwent 1- or 2-level lumbar fusion surgery. Demographic and radiographic (preoperative and 3-month postoperative) data were collected and compared between ASD and non-ASD groups. Binary logistic regression analysis was performed to evaluate adjusted associations between potential variables and ASD development. A subanalysis was further conducted to assess their relationships in the range of different PI values. With a mean follow-up duration of 70.6 months (range 60-121 months), 118 patients (50.4%) were diagnosed as having cranial radiological ASD. Univariate analyses showed that older age, 2-level fusion, worse preoperative pelvic tilt and LL, lower pre- and postoperative LDI, and more improvement in sagittal vertical axis were significantly correlated with the occurrence of ASD. No significant differences in the PI-LL and age-adjusted PI-LL (offset) were detected between ASD and non-ASD groups. Multivariate analysis identified postoperative LDI (OR 0.971, 95% CI 0.953-0.989, p = 0.002); 2-level fusion (OR 3.477, 95% CI 1.964-6.157, p < 0.001); and improvement of sagittal vertical axis (OR 0.992, 95% CI 0.985-0.998, p = 0.039) as the independent variables for predicting the occurrence of ASD. When stratified by PI, LDI was identified as an independent risk factor in the groups with low and average PI. Lower segmental lordosis (OR 0.841, 95% CI 0.742-0.954, p = 0.007) could significantly increase the incidence of ASD in the patients with high LDI. Age-adjusted PI-LL may have limited ability to predict the development of ASD. LDI could exert an important effect on diagnosing the occurrence of ASD in the cases with low and average PI, but segmental lordosis was a more significant risk factor than LDI in individuals with high PI.

Validation of Roussouly classification in predicting the occurrence of adjacent segment disease after short-level lumbar fusion surgery

BackgroundRecent studies demonstrated that restoring sagittal alignment to the original Roussouly type can remarkably reduce complication rates after adult spinal deformity surgery. However, there is still no data proving the benefit of maintaining ideal Roussouly shape in the lumbar degenerative diseases and its association with the development of adjacent segment disease (ASD). Thus, this study was performed to validate the usefulness of Roussouly classification to predict the occurrence of ASD after lumbar fusion surgery.Materials and MethodsThis study retrospectively reviewed 234 consecutive patients with lumbar degenerative diseases who underwent 1- or 2-level fusion surgery. Demographic and radiographic data were compared between ASD and non-ASD groups. The patients were classified by both “theoretical” [based on pelvic incidence (PI)] and “current” (based on sacral slope) Roussouly types. The patients were defined as “matched” if their “current” shapes matched the “theoretical” types and otherwise as “mismatched”. The logistic regression analysis was performed to identify the factors associated with ASD. Finally, clinical data and spinopelvic parameters of “theoretical” and “current” types were compared.ResultsWith a mean follow-up duration of 70.6 months, evidence of ASD was found in the 68 cases. Postoperatively, ASD group had more “current” shapes classified as type 1 or 2 and fewer as type 3 than the non-ASD group (p < 0.001), but the distribution of “theoretical” types was similar between groups. Moreover, 80.9% (55/68) of patients with ASD were mismatched, while 48.2% (80/166) of patients without ASD were mismatched (p < 0.001). A multivariate analysis identified age [odds ratio (OR) = 1.058)], 2-level fusion (OR = 2.9830), postoperative distal lordosis (DL, OR = 0.949) and mismatched Roussouly type (OR = 4.629) as independent risk factors of ASD. Among the four "theoretical" types, type 2 had the lowest lumbar lordosis, DL, and segmental lordosis. When considering the "current" types, current type 2 was associated with higher rates of 2-level fusion, worse DL, and greater pelvic tilt compared with other current types.ConclusionsDL loss and mismatched Roussouly type were significant risk factors of ASD. To decrease the incidence of ASD, an appropriate value of DL should be achieved to restore sagittal alignment back to the ideal Roussouly type.Level of Evidence: Level 4.

Exploring the incidence and risk factors of reoperation for symptomatic adjacent segment disease following cervical decompression and fusion

Patients with long-term follow-up after cervical decompression and fusion have often been noted to have development of adjacent segment degeneration with a smaller subset of these patients progressing to adjacent segment disease (ASD), which results in the development of new symptomatic radiculopathy or myelopathy referable to a site either directly above or below a prior fused segment. The cause of ASD is multifactorial often involving natural age-related progression of spondylosis, accelerated progression following cervical decompression and fusion, operative technique, and patient-related factors. The effect of age at the time of index cervical decompression and fusion on the need for reoperation for ASD is not fully understood. This study aims to establish underlying risk factors for the development of symptomatic cervical ASD following cervical decompression and fusion requiring reoperation in patients of various age groups. A retrospective database review of patients aged 20 or greater with insurance claims of primary cervical decompression and fusion over the course of 11 years and 10 months (January 01, 2010-October 31, 2022) was conducted using an insurance claims database. The primary outcome was to evaluate the incidence of cervical ASD requiring reoperation amongst patients stratified by age at the time of their primary procedure. Secondary outcomes included an evaluation of various risk factors for ASD following cervical decompression and fusion including surgeon-controlled factors such as the number of levels fused and approach taken, patient cervical pathology including cervical disc disorder and cervical spondylosis, and underlying patient medical comorbidities including osteoporosis and vitamin D deficiency, and substance use. A total of 60,292 patient records were analyzed, where the overall reoperation incidence for symptomatic ASD was 6.57%, peaking at 8.12% among those aged 30 to 39 and decreasing with age. Regression analysis revealed ages lower than 50 years as more predictive for the development of symptomatic ASD requiring reoperation. Multivariate regression analysis identified predictive factors for reoperation, including age, Elixhauser Comorbidity Index (ECI), multiple-level surgery, cervical spondylosis, cervical disc disorder, osteoporosis, and vitamin D deficiency. Notably, these factors had a variable impact across various age groups, as revealed by subgroup analysis. The incidence of reoperation secondary to symptomatic ASD is 6.57%, highest in those aged 30 to 39. The surgical approach had no significant impact on the need for reoperation, but multiple-level fusions posed a consistent risk in the development of symptomatic ASD requiring reoperation. Patient factors like degenerative disc disease, spondylosis, osteoporosis, and vitamin D deficiency were associated, urging further age-specific risk assessment and nonoperative intervention exploration.

Primary anterior lumbar interbody fusion, with and without posterior instrumentation: a 1,377-patient cohort from a multicenter spine registry

Lumbar interbody instrumentation techniques are common and effective surgical options for a variety of lumbar degenerative pathologies. Anterior lumbar interbody fusion (ALIF) has become a versatile and powerful means of decompression, stabilization, and reconstruction. As an anterior only technique, the integrity of the posterior muscle and ligaments remain intact. Adding posterior instrumentation to ALIF is common and may confer benefits in terms of higher fusion rate but could contribute to adjacent segment degeneration due to additional rigidity. Large clinical studies comparing stand-alone ALIF with and without posterior supplementary fixation (ALIF+PSF) are lacking. To compare rates of operative nonunion and adjacent segment disease (ASD) in ALIF with or without posterior instrumentation. Retrospective cohort study. Adult patients (≥18 years old) who underwent primary ALIF for lumbar degenerative pathology between levels L4 to S1 over a 12-year period. Exclusion criteria included trauma, cancer, infection, supplemental decompression, noncontiguous fusions, prior lumbar fusions, and other interbody devices. Reoperation for nonunion and ASD compared between ALIF only and ALIF+PSF. Reoperations were modeled as time-to-events where the follow-up time was defined as the difference between the primary ALIF procedure and the date of the outcome of interest. Crude cumulative reoperation probabilities were reported at 5-years follow-up. Multivariable Cox proportional hazard regression was used to evaluate risk of operative nonunion and for ASD adjusting for patient characteristics. The study consisted of 1,377 cases; 307 ALIF only and 1070 ALIF+PSF. Mean follow-up time was 5.6 years. The 5-year crude nonunion incidence was 2.4% for ALIF only and 0.5% for ALIF+PSF; after adjustment for covariates, a lower operative nonunion risk was observed for ALIF+PSF (HR=0.22, 95% CI=0.06-0.76). Of the patients who are deemed potentially suitable for ALIF alone, one would need to add posterior instrumentation in 53 patients to prevent one case of operative nonunion at a 5-year follow-up (number needed to treat). Five-year operative ASD incidence was 4.3% for ALIF only and 6.2% for ALIF+PSF; with adjustments, no difference was observed between the cohorts (HR=0.96, 95% CI=0.54-1.71). While the addition of posterior instrumentation in ALIFs is associated with lower risk of operative nonunion compared with ALIF alone, operative nonunion is rare in both techniques (<5%). Accordingly, surgeons should evaluate the added risks associated with the addition of posterior instrumentation and reserve the supplemental posterior fixation for patients that might be at higher risk for operative nonunion. Rates of operative ASD were not statistically higher with the addition of posterior instrumentation suggesting concern regarding future risk of ASD perhaps should not play a role in considering supplemental posterior instrumentation in ALIF.

Spinopelvic sagittal realignment and incidence of adjacent segment disease after single-segment posterior lumbar inter-body fusion using 12° lordotic cages-a 2-year prospective cohort study.

The importance of spinopelvic sagittal alignment for adjacent segment disease (ASD) after lumbar fusion surgery has been reported. However, no longitudinal cohort studies have determined the extent to which segmental alignment and spinopelvic global alignment can be achieved using 12° lordotic cages in posterior lumbar inter-body fusion (PLIF) and the extent to which the development of ASD can be prevented. The purpose of this study was to analyze changes in segmental and spinopelvic sagittal alignment after single-segment PLIF with 12° lordotic cages, to clarify the relationship between changes in segmental and spinopelvic sagittal alignment, and to report the incidence of ASD at 2 years postoperatively. Subjects in this 2-year prospective longitudinal cohort study were 28 patients who had undergone L4/5 PLIF using 12° lordotic cages. Incidence of operative ASD (O-ASD) was evaluated as clinical outcomes. Radiological measurements were examined preoperatively and at 3 months, 1 year and 2 years postoperatively. The following radiographic spinopelvic parameters were measured: segmental lordosis (SL) at L4/5; sagittal vertical axis (SVA); T1 pelvic angle (TPA); thoracic kyphosis (TK); lumbar lordosis (LL); sacral slope (SS); pelvic tilt (PT); and pelvic incidence (PI). With respect to radiological outcomes, changes in SL (ΔSL) and spinopelvic parameters and the incidence of radiological ASD (R-ASD) were evaluated. Correlations of ΔSL and changes in other spinopelvic parameters (ΔSVA, ΔTPA, ΔTK, ΔLL, ΔSS, ΔPT, and ΔPI-LL) between preoperatively and 3 months postoperatively were examined. The follow-up rate was 100% (n=28) at 1 year postoperatively and 96.4% (n=27) at 2 years postoperatively. No cases of O-ASD were seen during 2 years of follow-up. Significant realignment was observed and maintained at 2 years postoperatively in almost all spinopelvic sagittal parameters (SL, SVA, TPA, LL, PT, PI-LL). Regarding the correlation between ΔSL and other parameters, significant correlations were detected with ΔSVA (r=-0.37, P<0.05) and ΔLL (r=0.538, P<0.01). Three cases (11.1%) showed R-ASD at 2 years postoperatively. PLIF with 12° lordotic cages for L4 degenerative spondylolisthesis improved SL and global sagittal realignment, and achieved satisfactory clinical outcomes with a low incidence of ASD during 2 years of follow-up.

Comparative study of outcomes between allograft intervertebral disc transplantation and anterior cervical discectomy and fusion: a retrospective cohort study at least 5 years of follow-up

PurposeAdjacent segment degeneration (ASDeg) after anterior cervical discectomy and fusion (ACDF) seriously affects the long-term efficacy of the operation. Therefore, our team has done a lot of research on allograft intervertebral disc transplantation (AIDT) to prove its feasibility and safety. This study will compare the efficacy between AIDT and ACDF in the treatment of cervical spondylosis.MethodsAll patients who received ACDF or AIDT in our hospital from 2000 to 2016 and followed up for at least 5 years were recruited and divided into ACDF and AIDT groups. The clinical outcomes including functional scores and radiological data of both groups were collected and compared preoperatively and postoperatively at 1 week, 3 months, 6 months, 12 months, 24 months, 60 months and last follow-up. Functional scores included Japanese Orthopedic Association score (JOA), Neck Disability Index (NDI), Visual Analog Scale of Neck (N-VAS) and Arms (A-VAS) pain, the Short Form Health Survey-36 (SF-36) and imaging dates including digital radiographs in the lateral, hyperextension and flexion positions to assess the stability, sagittal balance and mobility of the cervical spine and magnetic resonance imaging (MRI) scans to assess the degeneration of adjacent segment.ResultsThere were 68 patients with 25 in AIDT group and 43 in ACDF group. Satisfactory clinical results were obtained in both groups, but the long-term NDI score and N-VAS score in the AIDT group were better. The AIDT obtained the same stability and sagittal balance of the cervical spine as fusion surgery. The range of motion of adjacent segments can be restored to the preoperative level after transplantation, but this increases significantly after ACDF. There were significant differences in the superior adjacent segment range of motion (SROM) between two groups at 12 months (P = 0.039), 24 months (P = 0.035), 60 months (P = 0.039) and the last follow-up (P = 0.011). The inferior adjacent segment range of motion (IROM) and SROM had a similar trend in the two groups. The ratio value of the greyscale (RVG) of adjacent segments showed a downward trend. At the last follow-up, the RVG decreased more significantly in the ACDF group. At the last follow-up, there was a significant difference in the incidence of ASDeg between the two groups (P = 0.000). And the incidence of adjacent segment disease (ASDis) is 22.86% in the ACDF group.ConclusionThe allograft intervertebral disc transplantation may be as an alternative technique to traditional anterior cervical discectomy and fusion for the management of cervical degenerative diseases. For the more, the results showed it would improve cervical kinematics and reduce the incidence of adjacent segment degeneration.

Minimally invasive LLIF surgery to decrease the occurrence of adjacent-segment disease compared to conventional open TLIF.

Lateral lumbar interbody fusion with percutaneous pedicle screw fixation (Mis-LLIF) can establish indirect decompression by lifting the vertebra with a large intervertebral cage, which causes less damage to the posterior elements. Thus, Mis-LLIF is expected to reduce the incidence of adjacent segment disease (ASD). The aim of the study was to compare the occurrence of ASD between Mis-LLIF and conventional open transforaminal interbody fusion (TLIF). A total of 156 patients (TLIF group = 88, Mis-LLIF group = 68) who underwent single-level lumbar interbody fusion (L2/3, L3/4, or L4/5) at a single institution between 2003 and 2018 with minimum 2-year follow-up were retrospectively reviewed. The incidence of symptomatic ASD requiring reoperation (S-ASD) and radiological adjacent segment degeneration (R-ASD) 2years postoperatively were investigated between 51 paired patients from both groups who were propensity score (PS) matched by demographic and baseline clinical data. The effect of characteristics arising from differences in surgical methods between Mis-LLIF and TLIF, such as the amount of distraction of the index fused level (∆H), on S-ASD and R-ASD was also examined. There were no significant differences in the incidence of S-ASD between the Mis-LLIF and TLIF groups (adjusted OR 1.3; 95% CI 0.41-3.9). There was no significant difference in the incidence of R-ASD between the Mis-LLIF and TLIF groups both at the cranial (adjusted OR 1.0; 95% CI 0.22-4.5) and caudal level (adjusted OR 1.5; 95% CI 0.44-5.3). On the other hand, ∆H was significantly higher in the Mis-LLIF group than in the TLIF group (3.6mm vs. 1.7mm, respectively, P < 0.0001), and was extracted as a significant independent risk factor for S-ASD (adjusted HR 2.7; 95% CI 1.1-6.3) and R-ASD at the cranial side (adjusted HR 6.4; 95% CI 1.7-24) in multivariable analysis with PS adjustment. The incidence of R-ASD or S-ASD was not significantly reduced in the Mis-LLIF group compared to the TLIF group, with greater ∆H potentially being a contributing factor. Using a thin cage in both TLIF and Mis-LLIF may decrease the occurrence of ASD.

Effect of adjacent segmental facet joint degeneration on adjacent segment disease after lumbar fusion and fixation

To explore the effect of facet joint degeneration in adjacent segments on the incidence of adjacent segment disease (ASD) after lumbar fusion and fixation. A retrospective analysis was performed on 138 patients who underwent L5S1 posterior lumbar interbody fusion (PLIF) from June 2016 to June 2019. Patients were divided into a degeneration group (68 cases) and a non-degenerative group (70 cases) based on the presence or absence of L4,5 facet joint degeneration before surgery (graded using the Weishaupt standard). Age, gender, body mass index (BMI), follow-up time, and preoperative L4,5 intervertebral disc degeneration (graded using the Pfirrmann standard) were collected for both groups. Clinical outcomes were evaluated using the visual analogue scale (VAS) and Oswestry disability index (ODI) at 1 and 3 months after surgery. The incidence and time of ASD after surgery were analyzed. There were no significant differences between the two groups in age, gender, BMI, follow-up time, or preoperative L4,5 intervertebral disc degeneration. Both groups showed significant improvement in VAS and ODI at 1 and 3 months after surgery (P<0.001), with no significant difference between the groups(P>0.05). However, there was a statistically significant difference in the incidence and timing of ASD between the groups (P<0.05). The degeneration group had 2 cases of ASD in gradeⅠdegeneration, 4 cases of ASD in gradeⅡdegeneration, and 7 cases of ASD in grade Ⅲ degeneration. There was a statistically significant difference between the number of patients with grade Ⅲ degeneration and those with gradesⅠandⅡASD (P<0.0167, Bonferroni correction). Preoperative degeneration of adjacent articular processes will increase the risk of ASD after lumbar fusion fixation, whereas gradeⅢ degeneration will further increase the risk.

Lumbar Arthroplasty is Associated with a Lower Incidence of Adjacent Segment Disease Compared to ALIF: A Propensity Matched Analysis.

Retrospective Cohort Study. To compare the rate of ASD between lumbar disc arthroplasty (LDA) and anterior lumbar interbody fusion (ALIF). Lumbar disc arthroplasty (LDA) and anterior lumbar interbody fusion (ALIF) are alternative surgical approaches used to treat lumbar degenerative disc disease. However, there is a paucity of studies comparing the risk of adjacent segment disease (ASD) following these procedures. Patients who underwent 1-2 level LDA or ALIF between 2010 and 2022 were identified in the PearlDiver Mariner insurance all-claims database. Exclusion criteria included history of prior lumbar spine surgery, or surgery for tumors, trauma, or infection. 1:1 propensity matching was performed using demographic factors, medical comorbidities, and surgical factors which were significantly associated with ASD. 1:1 Propensity matching created two equal groups of 1,625 patients without baseline differences who underwent LDA or ALIF. LDA was significantly associated with a lower risk of ASD (RR 0.932, 95% CI 0.899-0.967, P<0.001), and need for revision within 30 days (RR 0.235, 95% CI 0.079-0.698, P=0.007). There were no differences in all-cause surgical and medical complications between both groups. After risk adjustment for demographic and clinical characteristics, the results suggest that LDA is associated with a lower risk of adjacent segment disease compared to ALIF. LDA was also associated with lower hospital cost and shorter length of stay.

Reoperation Rates Due to ASD following Primary 1-2 level MIS vs. Open TLIF.

Retrospective analysis of prospectively collected data. To investigate the effect of the approach of the TLIF (open vs. MIS) on reoperation rates due to ASD at 2 - 4 year follow up. Adjacent segment degeneration (ASDeg) is a complication of lumbar fusion surgery which may progress to adjacent segment disease (ASD) and cause debilitating postoperative pain potentially requiring additional operative management for relief. Minimally invasive (MIS) transforaminal lumbar interbody fusion surgery (TLIF) has been introduced to minimize this complication but the impact on ASD incidence is unclear. For a cohort of patients undergoing 1- or 2-level primary TLIF between 2013 and 2019, patient demographics and follow-up outcomes were collected and compared between patients who underwent open versus MIS TLIF using Mann Whitney U test, Fischer's exact test, and binary logistic regression. 238 patients met inclusion criteria. There was a significant difference in revision rates due to ASD between MIS and open TLIFs at 2 (5.8% vs. 15.4%, P=0.021) and 3 (8% vs. 23.2%, P=0.03) year follow up, with open TLIFs demonstrating significantly higher revision rates. Surgical approach was the only independent predictor of reoperation rates at both 2 and 3 year follow ups (2-year P=0.009; 3-year P=0.011). Open TLIF was found to have a significantly higher rate of reoperation due to ASD compared to the MIS approach. Additionally, surgical approach (MIS vs. Open) appears to be an independent predictor of reoperation rates.

Cervical Radiculopathy: Focus on Factors for Better Surgical Outcomes and Operative Techniques.

For patients with cervical radiculopathy, most studies have recommended conservative treatment as the first-line treatment; however, when conventional treatment fails, surgery is considered. A better understanding of the prognosis of cervical radiculopathy is essential to provide accurate information to the patients. If the patients complain of persistent and recurrent arm pain/numbness not respond to conservative treatment, or exhibit neurologic deficits, surgery is performed using anterior or posterior approaches. Anterior cervical discectomy and fusion (ACDF) has historically been widely used and has proven to be safe and effective. To improve surgical outcomes of ACDF surgery, many studies have been conducted on types of spacers, size/height/position of cages, anterior plating, patients' factors, surgical techniques, and so forth. Cervical disc replacement (CDR) is designed to reduce the incidence of adjacent segment disease during long-term follow-up by maintaining cervical spine motion postoperatively. Many studies on excellent indications for the CDR, proper type/size/shape/height of the implants, and surgical techniques were performed. Posterior cervical foraminotomy is a safe and effective surgical option to avoid complications associated with anterior approach and fusion surgery. Most recent literature demonstrated that all three surgical techniques for patients with cervical radiculopathy have clear advantages and disadvantages and reveal satisfactory surgical outcomes under a proper selection of patients and application of appropriate surgical methods. For this, it is important to fully understand the factors for better surgical outcomes and to adequately practice the operative techniques for patients with cervical radiculopathy.

Effect of sagittal screw angle and distance of screw apex to superior endplate on adjacent segment disease after posterolateral lumbar fusion: a retrospective study

BackgroundNumerous complications of lumbar fusion surgery have been reported, with adjacent segment disease (ASD) being one of the most important. Few studies describe the effect of sagittal, horizontal screw angles and distance of pedicle screw apex to superior endplate on the incidence of ASD in lumbar spine. The purpose of this retrospective study is to evaluate the hypothesis that unsatisfactory pedicle screw insertion positions would increase the likelihood of ASD.MethodsOutpatients with lumbar spinal stenosis underwent posterolateral lumbar fusion at L4-S1 with a least 2-year follow-up were studied. ASD at L3–L4 was defined as a condition in which intervertebral disk narrowing, posterior vertebral opening, and vertebral slippage progress at the last follow-up in comparison with the postoperative. Independent t test was performed to compare data between two groups; Spearman analysis was performed to analyze the relationship between two continuous variables. Multivariate binary logistic models were performed to identify the independent risk factors of ASD. The receiver operating characteristic (ROC) curve was performed to measure model discrimination and Hosmer–Lemeshow (H–L) test was used to measure calibration. ROC curve evaluated the discrimination ability of sagittal screw angle and distance in predicting incidence of ASD.ResultsPatients in ASD group exhibit higher incidence of osteoporosis, higher Visual analogue scale (VAS), Oswestry disability index (ODI), bigger sagittal screw angle, shorter distance of pedicle screw apex to superior endplate than those in non-ASD group (p < 0.05). VAS, ODI at the last follow-up were positively correlated with Pfirrmann grade of L3–4 disk and sagittal screw angle, while negatively correlated with distance of screw apex to superior endplate (p < 0.05). Multivariate binary logistic model indicated that follow-up time (odds ratio [OR] 1.637, 95% confidence interval [CI] 1.186–2.260), distance of screw apex to superior endplate (OR 0.150, 95% CI 0.067–0.336), sagittal screw angle (OR 2.404, 95% CI 1.608–3.594) were statistically significant. The models showed great discrimination and calibration. The area under the curve of ASD identified by sagittal angle and distance was 0.895 and the cut-off values were 5.500° and 6.250 mm, respectively.ConclusionSagittal screw angle and distance of screw apex to superior endplate were significantly associated with the risk of ASD.

Adjacent segment disease after minimally invasive transforaminal lumbar interbody fusion for degenerative lumbar diseases: incidence and risk factors

Study designRetrospective study.ObjectivesTo explore the incidence and risk factors for symptomatic adjacent segment disease (ASD) in patients enveloped in degenerative lumbar diseases after minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF).MethodsData were retrospectively analyzed on 744 patients who underwent MIS-TLIF for degenerative lumbar diseases in our hospital from October 2012 to December 2018. The patients were divided into the ASD group and non-ASD (N-ASD) group on the basis of developing ASD at follow-up, and then the incidence of ASD was calculated. Clinical and radiological risk factors were assessed over time to determine their association with ASD by excluding less important factors.ResultsData were missing for 26 patients, while a total of 718 patients were successfully monitored after MIS-TLIF. Of the 718 individuals participated in the study, 34 (4.7%) patients plagued by ASD required surgical intervention. The average onset time of ASD was 62.7 ± 15.1 months. Univariate analysis results shows that age, bone mineral density (BMD), body mass index (BMI), preoperative adjacent intervertebral disc height and preoperative adjacent segment disc degeneration were significantly different between the ASD and N-ASD groups (p < 0.05). The logistic regression analysis results demonstrated that BMD (p = 0.039, OR = 0.986, 95% CI 0.899–1.115), BMI (p = 0.041, OR = 1.119, 95% CI 1.103–2.397), and preoperative adjacent intervertebral disc degeneration (p = 0.023, OR = 1.215, 95% CI 1.015–1.986) may be seen as risk factors for ASD after MIS-TLIF.ConclusionsThe incidence of ASD was about 4.7% in patients suffer from degenerative lumbar diseases after MIS-TLIF. BMD, BMI and preoperative adjacent intervertebral disc degeneration might be the risk factors for the occurrence of ASD after MIS-TLIF. Our research also suggested that patients with lower BMD, higher BMI and disc preoperative adjacent segment disc degeneration were more likely to develop ASD after MIS-TLIF.