Adjacent Segment Pathology Research Articles

Does Restoration of Lumbar and Segmental Cobb Angle Affect Fusion Outcome in Short-segment Posterior Lumbar Fusion?

To study the effect of lumbar lordosis change and pelvic parameters on surgical outcomes such as fusion vs. non-fusion (pseudarthrosis), Adjacent Segment Pathology (ASP), and re-operation in patients undergoing 1-, 2- and 3-level PLF. Adult patients with degenerative spine pathologies who had undergone PLF between L2 and L5 levels at an academic center between 2010 and 2020 were included. Pre-operative and early post-operative lateral standing X-Rays of the lumbar spine were used to measure pre-operative lumbar Cobb angle, Postoperative lumbar Cobb angle, pre-operative segmental Cobb angle (measured from the superior endplate of the upper instrumented vertebra to the inferior endplate of the lower instrumented vertebra), postoperative segmental Cobb angle, preoperative pelvic incidence (PI) and pelvic tilt (PT). Change in lumbar and segmental Cobb was calculated as postoperative Cobb angle (lumbar and segmental) minus preoperative Cobb angle. A total of 243 patients met our inclusion and exclusion criterion. Patients who had pseudarthrosis had a significantly less restoration of lumbar lordosis compared to those who did not, both for lumbar cobb angle change (-5.2±8.2 vs. -0.2±8.2; p=0.01) and segmental cobb angle change (-5.4±6.6 vs. -1.5±6.0; p=0.01). Moreover, PI was lower in patients who developed ASP vs. those who didn't. There was no significant difference in these measures (lumbar cobb angle changes and segmental cobb angle change) in patients who experienced ASP and those who did not. Better restoration of lumbar lordosis reduces rates of pseudarthrosis after short-segment PLF but has no association with rates of ASP.

Distal Junctional Failure After Fusion Stopping at L5 in Patients With Adult Spinal Deformity: Incidence, Risk Factors, and Radiographic Criteria.

To identify risk factors and establish radiographic criteria for distal junctional failure (DJF) in patients with adult spinal deformity (ASD), who underwent fusion surgery stopping at L5. This retrospective study was undertaken from January 2016 to December 2020. Patients with ASD who underwent fusion surgery (≥5 levels) stopping at L5 were analyzed. DJF was defined as symptomatic adjacent segment pathology at the lumbosacral junction necessitating consideration for revision surgery. Demographic data and radiographic measurements were compared between the DJF and non-DJF groups. Receiver operating characteristic curve analysis was performed to identify the radiographic cutoff value for DJF. Among 76 patients, 16 (21.1%) experienced DJF. DJF was associated with older age, antidepressant/anxiolytic medication, longer level of fusions, and worse preoperative sagittal alignment. Antidepressant/anxiolytic medication (odds ratio, 5.60) and preoperative pelvic incidence (PI)-lumbar lordosis (LL) mismatch>40° (odds ratio, 5.87) were independent risk factors for DJF. Without both factors, the incidence of DJF has been greatly reduced (9.1%). Two radiographic criteria were determined for DJF: last distal junctional angle (DJA)>-5° and Δ last DJA-post DJA>5°. When both criteria were met, the sensitivity and specificity of the DJF were 93.3% and 91.7%, respectively. Use of antidepressant/anxiolytic medication and preoperative PI-LL mismatch >40° were independent risk factors for DJF. DJF could be diagnosed using postoperative changes in the DJA. If both criteria were met, DJF could be strongly suggested.

Cervical Disk Arthroplasty: Updated Considerations of an Evolving Technology.

For years, anterior cervical diskectomy and fusion has been considered the benchmark for patients with cervical radiculopathy/myelopathy. However, concerns regarding adjacent segment pathology have promoted the popularity of cervical disk arthroplasty (CDA) with its motion-preserving properties. To replicate the natural cervical disk's six degrees of freedom and compressibility in cervical spine implants, designers need to carefully consider the level of constraint for stability and material selection. Recent CDA designs have incorporated strategies to facilitate unrestricted or semirestricted motion, deploying various articulating components and materials with distinct wear and compressibility properties. To optimize outcomes, patient selection considering additional degeneration of the cervical spine is critical. Clinical long-term studies have been reported in industry-funded FDA investigational device exemption and nonindustry-funded data for one-level and two-level CDA. There are limited data available on three-level and four-level CDA. Adverse events such as heterotopic ossification, osteolysis, migration, subsidence, and failure have been described, where analysis from explanted devices yields insight into in vivo wear and impingement performance. CDA has shown short-term cost advantages, such as decreased procedural expenses. Nonetheless, long-term analysis is necessary to assess possible economic tradeoffs. Advancements in designs may lead to improved implant longevity while evidence-based decision making will guide and responsibly manage the rapid advancement in CDA technology.

Single-Level Anterolateral and Posterior Interbody Fusion Techniques are Associated With Equivalent Long-Term Lumbar Reoperations.

Retrospective cohort study. This study compares reoperation rates and complications following single-level anterior lumbar interbody fusion (ALIF)/lateral lumbar interbody fusion (LLIF) and transforaminal lumbar interbody fusion (TLIF)/posterior lumbar interbody fusion (PLIF). ALIF, LLIF, TLIF, and PLIF are widely used for degenerative disc disease. Lumbar interbody fusions have high rates of reoperation, primarily related to adjacent segment pathology and pseudarthrosis. The PearlDiver database was queried for patients (2010-2021) who had single-level ALIF/LLIF or TLIF/PLIF with same-day, single-level posterior instrumentation. ALIF/LLIF were combined, and similarly, TLIF/PLIF were combined, given how these operations are indistinguishable from Current Procedural Terminology coding. All patients were followed for ≥2 years and excluded if they had spinal traumas, fractures, infections, or neoplasms before surgery. The two cohorts, ALIF/LLIF and TLIF/PLIF, were matched 1:1 based on age, sex, Elixhauser-comorbidity index, smoking status, and diabetes. The primary outcome was the incidence of all-cause subsequent lumbar operations. Secondary outcomes included 90-day surgical complications. After 1:1 matching, each cohort contained 14,070 patients. All-cause subsequent lumbar operations were nearly identical at five-year follow-up (9.4% ALIF/LLIF vs. 9.5% TLIF/PLIF, P =0.91). Survival analysis using all-cause subsequent lumbar operations as the endpoint showed an equivalent 10-year survival rate of 86.0% (95%CI: 85.2-86.8). Within 90 days, TLIF/PLIF had more infections (1.3% vs. 1.7%, P =0.007) and dural injuries (0.2% vs. 0.4%, P =0.001). There was no difference in wound dehiscence, hardware complications, or medical complications. As utilized in real-world clinical practice, single-level anterolateral versus posterior approaches for interbody fusion have no effect on long-term reoperation rates.

Does the Number of Interbody Devices Affect the Fusion Outcome in Short-Segment Posterior Lumbar Fusion?

Interbody devices (IBDs) have been shown to improve outcomes when used in posterior lumbar fusion (PLF) surgery; however,the exact extent of their clinical benefit remains a current topic of interest. Our primary objective in this study was to identify whether the use of an IBD at every level of fusion construct would affect fusion outcomes such as adjacent segment pathology (ASP) and pseudarthrosis after one- to three-level PLF surgery. This was a single-institution retrospective study. We studied the association of factors such as smoking status, BMI, gender, age, and number of IBDs on the development of ASP and pseudarthrosis. To study the effect of independent variables on ASP and pseudoarthrosis, univariate and multivariate regression analyses were used. The study included 2,061 patients with a history of posterior lumbar fusion who were identified and reviewed. Among these, 363 patients met our inclusion criteria; 247 patients had a minimum follow-up of six months and were finally included in the study. The median follow-up was 30 months. Among the 247 patients, 105 (42.5%) and 24 (9.7%) experienced ASP and pseudarthrosis, respectively. Gender and use of IBD significantly affected the presence of pseudarthrosis (with a higher rate in males and those without any IBDs). Gender, age, BMI, and use of IBDs did not affect ASP. Moreover, using an IBD at each fused level reduced the pseudarthrosis rate significantly compared to when IBDs were not used at all levels (7.3% vs. 27.6%, p <0.001), while there was no significant difference in the rate of ASP (43.6% vs. 34.5%, p = 0.35). In patients undergoing one- to three-level PLF surgery, the use of an IBD at all levels of the fusion construct significantly reduces the rate of pseudarthrosis. There was no significant correlation between the rates of ASP. Studies with a larger sample size and a longer follow-up time are suggested to validate our results for pseudoarthrosis and ASP. Our results suggest the use of an IBD per fusion level in short-segment PLF surgeries.

The impact of over-distraction on adjacent segment pathology and cage subsidence in anterior cervical discectomy and fusion

Over-distraction has been shown to be a risk factor for cage subsidence and postoperative neck pain after anterior cervical discectomy and fusion (ACDF). Biomechanical studies have demonstrated increased adjacent segment intradiscal pressure after ACDF. The purpose of this study is to determine if over-distraction of the index disc has an effect on adjacent segment pathology. A consecutive series of 145 patients who received primary ACDF for cervical degenerative pathologies from January 2010 to December 2017 were retrospectively reviewed. The patients were divided into: (1) Over-distraction group (postoperative–preoperative index disc height ≥ 2 mm), and (2) No-distraction group (postoperative–preoperative index disc height < 2 mm). Outcome measures included radiographic parameters, Japanese Orthopaedic Association (JOA) score, and incidences of cage subsidence, radiological and clinical adjacent segment pathologies (RASP and CASP) were compared between the two groups preoperatively, postoperatively, and at the final follow-up. The two groups were comparable with respect to age, follow-up length, JOA score, incidence of CASP, and radiographic parameters. The Over-distraction group (83 patients; 115 levels) had smaller preoperative index disc height (4.5 vs. 5.2 mm, p < 0.001), but taller postoperative index disc height (7.7 vs. 6.6 mm, p < 0.001) than No-distraction group (62 patients; 90 levels) Furthermore, significantly higher incidences of cage subsidence (47% vs. 31%, p = 0.04) and RASP (any progression: 48% vs. 15%, p < 0.001; progress ≥ 2 grades: 25% vs. 7%, p = 0.001) were observed in the Over-distraction group. The multivariate analysis indicated that over-distraction and multilevel fusion were independent risk factors for RASP. There were no clinical outcome differences between the Over-distraction group and the No-distraction group in ACDF. Over-distraction of the index level of ≥ 2 mm should be avoided because it significantly increases the incidences of RASP and cage subsidence.

Effect of Body Mass Index on Fusion Outcome After Short-Segment Posterior Lumbar Fusion

Obesity is a growing epidemic in the United States. While many adverse effects of obesity on surgical outcome are well studied, a direct correlation among obesity, pseudarthrosis, and adjacent segment pathology is not well defined. In this study we aimed to identify the effect of body mass index (BMI) on pseudarthrosis, adjacent segment pathology (ASP), and reoperation after short-segment (1-3 levels) open posterior lumbar fusion (PLF). This is a retrospective study of patients with degenerative spine pathologies who underwent 1-, 2-, or 3-level PLF surgery between 2010 and 2020. The relevant medical and imaging records were reviewed, and the following variables were recorded: age, gender, BMI, smoking status, surgical details, follow-up length, need for reoperation, indication for reoperation (pseudarthrosis or occurrence of ASP). We included363 patients in our study. Twenty-five patients (6.9%) developed pseudarthrosis, 109 (30%) developed ASP, and 104 patients (28.7%) underwent reoperation for either of these reasons. BMI was significantly less in those who developed pseudarthrosis compared with those who did not (28.6 ± 5.5 vs. 31.2 ± 6.2, respectively; P= 0.04). BMI was not significantly different in those who developed ASP or underwent reoperation compared with those who did not (P= 0.06 and 0.08, respectively). Multivariate regression analysis showed none of the variables in the model (age, gender, tobacco use, BMI, and its classes) significantly predicted pseudarthrosis, ASP, or reoperation (P > 0.1 for all variables). Obese patients undergoing short-segment open PLF have comparable results in terms of pseudarthrosis, ASP, and reoperation.

Cervical Disc Arthroplasty vs Anterior Cervical Discectomy and Fusion at 10 Years: Results From a Prospective, Randomized Clinical Trial at 3 Sites

Over the past 20 years, multiple randomized controlled trials have shown cervical disc arthroplasty (CDA) to be safe and effective for treating 1- and 2-level degenerative disc disease (DDD). The purpose of this postmarket study is to compare 10-year outcomes between CDA and anterior cervical discectomy and fusion (ACDF) from a randomized study at 3 centers. This study was a continuation of a randomized, prospective, multicenter clinical trial comparing CDA with the Mobi-C cervical disc (Zimmer Biomet) vs ACDF. Following completion of the 7-year US Food and Drug Administration study, 10-year follow-up was obtained from consenting patients at 3 high-enrolling centers. The clinical and radiographic endpoints collected at 10 years included composite success, Neck Disability Index, neck and arm pain, short form-12, patient satisfaction, adjacent-segment pathology, major complications, and subsequent surgery. A total of 155 patients were enrolled (105 CDA; 50 ACDF). Follow-up was obtained from 78.1% of patients eligible after 7 years. At 10 years, CDA demonstrated superiority to ACDF. Composite success was 62.4% in CDA and 22.2% in ACDF (P < 0.0001). The cumulative risk of subsequent surgery at 10 years was 7.2% vs 25.5% (P = .001), and the risk of adjacent-level surgery was 3.1% vs 20.5% (P = .0005) in CDA vs ACDF, respectively. The progression to radiographically significant adjacent-segment pathology at 10 years was lower in CDA vs ACDF (12.9% vs 39.3%; P = 0.006). At 10 years, patient-reported outcomes and change from baseline were generally better in CDA patients. A higher percentage of CDA patients reported they were "very satisfied" at 10 years (98.7% vs 88.9%; P = 0.05). In this postmarket study, CDA was superior to ACDF for treating symptomatic cervical DDD. CDA was statistically superior to ACDF for clinical success, subsequent surgery, and neurologic success. Results through 10 years demonstrate that CDA continues to be a safe and effective surgical alternative to fusion. The results of this study support the long-term safety and effectiveness of cervical disc arthroplasty with the Mobi-C.

Medium and long-term radiographic and clinical outcomes of Dynesys dynamic stabilization versus instrumented fusion for degenerative lumbar spine diseases

BackgroundDynesys stabilization (DS) is utilized to preserve mobility at the instrumental segments and prevent adjacent segment pathology in clinical practice. However, the advantages of DS method in medium and long-term follow-up remain controversial.ObjectiveTo compare the radiographic and clinical outcomes between DS and instrumented fusion in the treatment of degenerative lumbar spine disease with or without grade I spondylolisthesis with a minimum follow-up period of 2 years.MethodsWe conducted a comprehensive search of PubMed, EMBASE, Cochrane, and Web of Science databases, Chinese National Knowledge Databases, and Wanfang Database for potentially eligible articles. Clinical outcomes were assessed in terms of VAS and ODI scores, screw loosening and breakage, and surgical revision. Radiographic outcomes were assessed in terms of postoperative range of movement (ROM) and disc heigh. Moreover, adjacent segment degeneration (ASDeg) and adjacent segment disease (ASDis) were evaluated.ResultsSeventeen studies with 1296 patients were included in the meta-analysis. The DS group was associated with significantly lower postoperative VAS scores for low-back and leg pain, and lower rate of surgical revision than the fusion group. Moreover, the Dynesys group showed significantly less ASDeg than the fusion group but showed no significant advantage over the fusion group in terms of preventing ASDis. Additionally, the ROM at the stabilized segments of the fusion group decreased significantly and that at the adjacent segments increased significantly compared with those of the DS group.ConclusionDS showed comparable clinical outcomes and provided benefits in preserving the motion at the stabilized segments, thus limiting the hypermobility at the adjacent segments and preventing ASDeg compared with the fusion method in degenerative disease with or without grade I spondylolisthesis.

Adjacent Segment Disease

Spinal fusion is gold-standard treatment for degenerative disc disease (DDD) both at cervical and lumbar spine, and it is time tested. Perhaps it has its bundle of complications. Elimination of motion results in accentuated degeneration of adjacent segments leading to adjacent segment degeneration radiographically and, if symptomatic, leads to adjacent segment disease. There is still a debate on whether there is such an entity or whether it is a manifestation of natural history or an iatrogenic phenomenon. Motion preservation surgeries were developed to address the same issue, which includes total disc replacement, nucleus replacement, interspinous implants, and dynamic posterior stabilization systems. The primary goal of motion preservation surgery is to maintain normal or near-normal motion in an attempt to prevent adverse outcomes, which are commonly seen with conventional spinal fusion, most notably the development of adjacent-level DDD. A search was conducted in PubMed using the terms (“adjacent segment”) AND (“disease” OR “degeneration” or “pathology”). Then the articles were shortlisted based on time of publication (2005 onward), publication in English and inclusion of human subjects. This resulted in 253 articles. Another search for ((“Motion preservation”) AND (“Spine”)) OR (“Adjacent segment disease”) OR (“Adjacent segment pathology”) OR (“Adjacent segment degeneration”) yielded 76 articles. This narrative review discusses various issues pertaining to the current evidence regarding adjacent segment disease (ASD), including the controversy on whether ASD is actually an entity, its etiopathogenesis, clinical features, as well as the role of motion preservation technologies to reduce its incidence. There is still enthusiasm and concerns regarding the benefits of motion preservation surgery since it is still an area of ongoing research.

Adjacent Segment Pathology in Spinal Fusion Surgery

Adjacent Segment Pathology in Spinal Fusion Surgery

A dynamic pedicle screw system using polyethylene insert for the lumbar spine.

Rigid spinal fusion with instrumentation has been widely applied in treating degenerative spinal disorders and has shown excellent and stable surgical results. However, adjacent segment pathology or implants' loosening could be problematic due to the spine's segmental fusion. Therefore, this study verified a novel concept for posterior stabilization with polyethylene inserts inside a pedicle screw assembly using bone models. We observed that although the gripping capacity of the dynamic pedicle screw system using a tensile and compression tester was less than half that of the rigid pedicle screw system, the flexion-extension moment of the dynamic pedicle screws was significantly lower than that of the rigid pedicle screws. Furthermore, while the bending force of the rigid pedicle screw assembly increased linearly with an increase in the bending angle throughout the test, that of the dynamic pedicle screw assembly also increased linearly until a bending angle of 2.5° was reached. However, this angle decreased at a bending angle of more than 2.5°. Additionally, the fatigue test of 1.0 × 106 cycles showed that the pull-out force of the dynamic pedicle screws from two different polyurethane foam blocks was significantly higher than that of the rigid pedicle screws. Therefore, based on our results, we propose that the device can be applied in clinical cases to reduce screw loosening and adjacent segment pathology.

Association of Craniocervical Sagittal Alignment With the Outcomes of Cervical Disc Replacement.

Retrospective cohort study. To explore the association between craniocervical sagittal balance and clinical and radiological outcomes of cervical disc replacement (CDR). Patients who underwent 1-level and 2-level CDR were retrospectively analyzed. Clinical outcomes were evaluated using scores on the Japanese Orthopaedic Association (JOA), Visual Analogue Scale (VAS), and Neck Disability Index (NDI). The craniocervical sagittal alignment parameters, including the C0-C2 Cobb angle, C2-C7 Cobb angle, C2 slope, T1 slope, C2-C7 sagittal vertical axis (SVA), C1-C7 SVA, the center of gravity of the head (CGH)-C7 SVA, and range of motion (ROM) at the surgical segments were measured. A total of 169 patients were involved. Significantly lower pre- and postoperative C2 slope and CGH-C7 SVA were found in arthroplasty levels with better ROMs. Patients with a higher preoperative C2 slope and CGH-C7 SVA had lower cervical lordosis and ROM after surgery. There were no significant differences in the clinical outcomes between patients with different sagittal balance statuses. C2-C7 SVA and CGH-C7 SVA were significantly associated with radiographic adjacent segment pathology (rASP). Craniocervical sagittal balance is associated with cervical lordosis and ROM at the index level after CDR. A higher preoperative SVA is related to the presence and progression of rASP. A relationship between sagittal alignment and clinical outcomes was not observed.

Research protocol: Cervical Arthroplasty Cost Effectiveness Study (CACES): economic evaluation of anterior cervical discectomy with arthroplasty (ACDA) versus anterior cervical discectomy with fusion (ACDF) in the surgical treatment of cervical degenerative disc disease — a randomized controlled trial

IntroductionTo date, there is no consensus on which anterior surgical technique is more cost-effective in treating cervical degenerative disc disease (CDDD). The most commonly used surgical treatment for patients with single- or multi-level symptomatic CDDD is anterior cervical discectomy with fusion (ACDF). However, new complaints of radiculopathy and/or myelopathy commonly develop at adjacent levels, also known as clinical adjacent segment pathology (CASP). The extent to which kinematics, surgery-induced fusion, natural history, and progression of disease play a role in the development of CASP remains unclear. Anterior cervical discectomy with arthroplasty (ACDA) is another treatment option that is thought to reduce the incidence of CASP by preserving motion in the operated segment. While ACDA is often discouraged, as the implant costs are higher while the clinical outcomes are similar to ACDF, preventing CASP might be a reason for ACDA to be a more cost-effective technique in the long term.Methods and analysisIn this randomized controlled trial, patients will be randomized to receive ACDF or ACDA in a 1:1 ratio. Adult patients with single- or multi-level CDDD and symptoms of radiculopathy and/or myelopathy will be included. The primary outcome is cost-effectiveness and cost-utility of both techniques from a healthcare and societal perspective. Secondary objectives are the differences in clinical and radiological outcomes between the two techniques, as well as the qualitative process surrounding anterior decompression surgery. All outcomes will be measured at baseline and every 6 months until 4 years post-surgery.DiscussionHigh-quality evidence regarding the cost-effectiveness of both ACDA and ACDF is lacking; to date, there are no prospective trials from a societal perspective. Considering the aging of the population and the rising healthcare costs, there is an urgent need for a solid clinical cost-effectiveness trial addressing this question.Trial registrationClinicalTrials.gov NCT04623593. Registered on 29 September 2020.

43. Comparison of radiographic adjacent segment pathology at five years following minimally invasive compared to open lumbar 1- to 2-level fusion surgery

<h3>BACKGROUND CONTEXT</h3> Adjacent segment pathology remains a major cause of morbidity among patients receiving posterior lumbar instrumented fusion. Its occurrence is proposed to be secondary to the increased motion and biomechanical stresses from fused to unfused segment. Additionally, progressive degenerative processes in the spine can also be influenced by surgery-related factors that alter the spine biomechanics as a result of muscle destruction and facet joint violation. Controversy in the rates of radiographic adjacent segment pathology (RASP) after lumbar fusion surgery has stemmed by and large from variable reporting in the literature with short long-term follow-up periods and no comparison between muscle splitting minimally invasive (MIS) approach and posterior midline open fusions. We report a single-center cohort analysis of patients undergoing lumbar fusion surgery and describe the rate of RASP between patients undergoing minimally invasive tubular approach (MIS) vs open posterior fusion technique. <h3>PURPOSE</h3> The objective of this study is to evaluate the rate of RASP between MIS and open lumbar fusion surgery within 5-year follow-up period. <h3>STUDY DESIGN/SETTING</h3> Observational study. <h3>PATIENT SAMPLE</h3> Adults with degenerative lumbar disease who underwent 1- to 2-level open and MIS fusion at our institution from January 2006 to December 2016. <h3>OUTCOME MEASURES</h3> Rate of radiographic adjacent segment pathology. <h3>METHODS</h3> The authors conducted a retrospective chart review of patients diagnosed with degenerative lumbar disease who had undergone 1- to 2-level fusion between January 2006 to December 2016. Cases with upright lumbar radiographs were included in this sub-analysis. The patients were divided into an MIS fusion group and an open surgery group based on the surgical technique performed. The two groups were compared for baseline demographic features, surgical variables and diagnosis at index surgery. Adjacent segment pathology was evaluated using radiographs taken at the 5-year follow-up period. RASP is defined by the presence of any one or combination of (1) disc degeneration (height loss), (2) development of spondylolisthesis and (3) coronal deformity/lateral listhesis. Analysis was confined to rates of development of RASP with no attempt of correlating with symptomatic adjacent segment pathology. Logistic regression analysis was performed to assess relationship of demographic factors with development of RASP <h3>RESULTS</h3> A total of 165 patients were included: MIS (n = 73) and (n = 92) open. There was no significant difference between two groups in age, sex, diagnosis at index surgery, level of fusion and baseline RASP. Fusion involved one level in 72.7 % of cases and 2 levels in 27.3%. The overall incidence of RASP was 41.2%, with incidence of 36.9% in MIS group and 44.6% in the open surgery group, showing no significant difference between the two groups (p = 0.5246). In those with RASP, the most common radiographic finding was disc degeneration (height loss) for both cohorts (100% vs 87.8%, p = 0.264) with the majority occurring cephalad to previous instrumentation. Logistic regression analysis did not show significant correlation between sex, age, index diagnosis, presence of baseline RASP and the prevalence of RASP at 5 years. <h3>CONCLUSIONS</h3> The prevalence of radiographic adjacent segment pathology did not statistically differ between MIS and open lumbar fusion surgery at minimum of 5-year follow-up. Baseline demographics or primary pathoanatomical diagnosis did not correlate to the presence of RASP 5 years following surgery in either group. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

Letter to the Editor Regarding “The Incidence of Adjacent Segment Pathology After Cervical Disc Arthroplasty Compared with Anterior Cervical Discectomy and Fusion: A Systematic Review and Meta-Analysis of Randomized Clinical Trials”

Letter to the Editor Regarding “The Incidence of Adjacent Segment Pathology After Cervical Disc Arthroplasty Compared with Anterior Cervical Discectomy and Fusion: A Systematic Review and Meta-Analysis of Randomized Clinical Trials”

Prevalence of Bertolotti's Syndrome in Lumbosacral Surgery Procedures.

IntroductionBertolotti’s syndrome (BS) describes the relationship between low back pain (LBP) and lumbosacral transitional vertebra (LSTV). It is a factor that is sometimes overlooked when it comes to evaluating and treating LBP.Because of the different diagnostic modalities and criteria used in the research, the LSTV incidence in the general population varies greatly, and hence the link between LSTV and LBP remains contentious. Some researchers found no link between low back pain and LSTV. As a result, the management of BS remains controversial and multiple treatments have been suggested, including locally injected steroid and various surgical approaches.MethodsThis retrospective cohort study included a total of 288 patients who underwent lumbosacral surgical procedures for disc prolapse, lumbar canal stenosis, spondylolithesis and post-laminectomy syndrome during the period between January 2016 and May 2020. Trauma, tumours and scoliotic patients were excluded. All data were collected from the departmental database. All cases were done by the same surgical team at El Hadra University Hospital Spine Unit, Egypt. The patients were divided into two groups. Group A consisted of 133 patients in whom LSTV was detected by radiologic findings. In contrast, Group B consisted of 155 patients in whom LSTV was not detected.ResultsIn our study, the overall prevalence of LSTV among 288 patients who underwent lumbosacral surgical interventions was 46.2%. On comparing the incidence of surgical interventions between both groups, there was non-significant difference in most of surgical interventions. The incidence of L3-5 double-level posterior lumbar interbody fusion (PLIF) among LSTV patients was 16.5% compared to 4.61% in the other group. The incidence of L4-S1 double-level PLIF among LSTV patients was 15.04% compared to 7.24% in the other group.Regarding adjacent segment pathology, the incidence of lumbar canal stenosis and degenerative spondylolithesis was higher in the LSTV group (20.3% and 11.3%, respectively) compared to the non-LSTV group (9.7% and 5.2%, respectively). The incidence of disc prolapse was lower in the LSTV group (56.39%) compared to the non-LSTV group (71.0%). There was a non-significant difference between the incidence of lytic spondylolithesis and postlaminectomy syndrome between both groups.ConclusionThe overall prevalence of LSTV among all cases who underwent lumbosacral surgical procedures at the El Hadra University Hospital was 46.2%. The incidence of lumbar canal stenosis and degenerative spondylolithesis was higher in the LSTV group compared to the non-LSTV group. However, the incidence of disc prolapse was lower in the LSTV group compared to the non-LSTV group. The incidence of disc prolapse and degenerative spondylolithesis at the L4-5 level was higher in the LSTV group compared to the non-LSTV group. In contrast, the incidence at L5-S1 was lower in the LSTV group compared to the non-LSTV group. Hence, LSTV is considered a risk factor for disc degenerative changes at the level above the transitional vertebra level.

Artificial disc replacement and adjacent-segment pathology: 10-year outcomes of a randomized trial.

Artificial disc replacement (ADR) is designed to preserve motion and thus protect against adjacent-segment pathology (ASP) and act as an alternative treatment to fusion surgery. The question remains, how well do ADR devices perform after 10 years of follow-up compared with fusion surgery in terms of patient satisfaction, sustainability, and protection against ASP? This was the 10-year follow-up study of 153 participants who underwent ADR or fusion surgery after anterior decompression due to cervical degenerative radiculopathy (ISRCTN registration no. 44347115). Scores on the Neck Disability Index (NDI), EQ-5D, and visual analog scale for neck and arm pain were obtained from the Swedish Spine Registry and analyzed using ANCOVA. Information about secondary surgical procedures was collected from medical records and presented as Kaplan-Meier curves. MRI and flexion-extension radiography were performed, and ASP was graded according to the Miyazaki classification system. Ten participants were lost to follow-up, which left 143 participants (80 underwent ADR and 65 underwent anterior cervical discectomy and fusion). There were no differences between groups in terms of patient-reported outcome measures (10-year difference in NDI scores 1.7 points, 95% CI -5.1 to 8.5, p = 0.61). Nineteen (24%) participants in the ADR group compared with 9 (14%) in the fusion group underwent secondary surgical procedures. The higher reoperation rate of the ADR group was mainly due to 11 female participants with device loosening. The rates of reoperation due to ASP were similar between groups, which was confirmed with MRI assessment of ASP that also showed no differences between the groups (p = 0.21). This was the first 10-year follow-up study to compare ADR with fusion surgery and to provide MRI information for the assessment of ASP. The authors found no benefit of ADR over fusion surgery after anterior decompression for cervical degenerative radiculopathy.

What's New in Spine Surgery.

What's New in Spine Surgery.

Pre-existing adjacent level foraminal stenosis does not affect the outcome of a single level lumbar interbody fusion

BackgroundThe aim of this study was to investigate whether or not pre-existing asymptomatic neuroforaminal stenosis adjacent to the fusion level develops adjacent segment disease (ASD) after single-level lumbar interbody fusion. Summary and background dataRisk factors of ASD after spinal fusion have been well investigated, but there have been few studies focused on the relationship between ASD and pre-existing asymptomatic neuroforaminal stenosis. MethodsA total of 302 patients who had undergone a single-level lumbar interbody fusion were reviewed at a minimum of 2 year follow-up. They were 109 men and 193 women with a mean age of 68.8 years. Follow-up periods was averaged 53.5 months. ASD was defined as neurological deterioration related to adjacent segment pathologies which required an additional surgery. Based on the pathologies, patients were divided into three categories: ASD due to foraminal stenosis (ASD-FS), ASD due to central stenosis (ASD-CS), and ASD due to herniated disc (ASD-HD). Measured variables were age, gender, diagnosis, BMI, decompression procedures at adjacent segments, preoperative anterior/posterior slip, asymptomatic neuroforaminal stenosis, facet tropism, and postoperative spinopelvic parameters. ResultsThirty-eight patients (12.6%) developed ASD. There were 15 patients with ASD-FS, 18 patients with ASD-CS, and five patients with ASD-HD. Lumbar lordosis (LL) and sacral slope (SS) were significantly smaller and pelvic tilt (PT) was significantly larger in ASD-FS. Asymptomatic neuroforaminal stenosis was detected preoperatively in 33.3% of the ASD-FS group, and 18.6% of non-ASD group; the incidence was not significantly different. ConclusionsAdjacent-level neuroforaminal stenosis was not a significant risk of ASD after single-level lumbar interbody fusion, and might not need to be fused if asymptomatic.