Degenerative Lumbar Spine Pathology Research Articles

Substance P Level in Patients with Degenerative Lumbar Spine Disorder undergoing Decompressive Surgery: An Observational Study

Introduction: Patients with degenerative lumbar spine disorders experience Chronic Low Back Pain (CLBP) for which they undergo decompressive surgery. Substance P (SP), a neurotransmitter which acts as a modulator of pain perception and transmits nociceptive signals via primary afferent fibers to the spinal cord and brainstem. In chronic painful conditions, SP level can be associated with the severity of pain and gets altered; however, this correlation is not present in acute pain. Aim: To evaluate serum SP level in CLBP patients undergoing decompressive spine surgery. Materials and Methods: The present study was a prospective observational study, in which 30 patients with CLBP undergoing decompressive spine surgery were enrolled. Along with them, one first-degree relative of each patient and an equal number of healthy volunteers were included in the study group. Patients were followed-up on the 5th postoperative day and at two months after surgery for the evaluation of SP levels and Visual Analogue Scale (VAS) scores. Statistical data analysis was carried out using IBM PASW Statistics (SPSS) 25.0 version software. SP levels followed a non normal distribution and were compared by Mann-Whitney U or Kruskal Wallis test (for 2 or more groups, respectively) and correlated using Spearman rank correlation. Results: Patients undergoing decompressive spine surgery had a significantly higher SP level (97.5 picogram/mL (pg/mL)) than healthy volunteers (23.22 pg/mL), p-value <0.001. The serum SP levels in patients were found to be significantly reduced on the 5th postoperative day (31.7 pg/mL) and at two months after surgery (48.5 pg/mL), p-value=0.043. In contrast, there was no discernible change in the VAS score, which did not correlate with the fall in SP levels on the 5th postoperative day. Conclusion: SP level was elevated in subjects with degenerative lumbar spine disorders undergoing decompressive surgery. Higher levels of SP can be attributed to CLBP in those patients. SP can be contemplated as a biomarker of pain due to degenerative lumbar spine pathology. However, further studies are warranted to substantiate this.

REASON(S) FOR REFUSAL OF SURGERY IN PATIENTS WITH ESTABLISHED DEGENERATIVE LUMBAR PATHOLOGY

Low back pain is the single most common cause for disability in individuals aged 45 years or younger, it carries tremendous weight in socioeconomic considerations. Degenerative aging of the structural components of the spine can be associated with genetic aspects, lifetime of tissue exposure to mechanical stress & loads and environmental factors. Mechanical consequences of the disc degenerative include loss of disc height, segment instability and increase the load on facets joints. All these can lead to degenerative changes and osteophytes that can narrow the spinal canal. Surgery is indicated in patients with spinal stenosis who have intractable pain, altered quality of life, substantially diminished functional capacity, failed non-surgical treatment and are not candidates for non-surgical treatment. The aim was to determine the reasons for refusal of surgery in patients with established degenerative lumber spine pathology eligible for surgery.All patients meeting the study criteria, patients older than 18 years, patients with both clinical and radiological established symptomatic degenerative lumbar spine pathology and patients eligible for surgery but refusing it were recruited. Questionnaire used to investigate reasons why they are refusing surgery.Results 59 were recruited, fifty-one (86.4 %) females and eight (13.6 %) males. Twenty (33.8 %) were between the age of 51 and 60 years, followed by nineteen (32.2 %) between 61 and 70 years, and fourteen (23.7 %) between 71 and 80 years. 43 (72 %) patients had lumber spondylosis complicated by lumber spine stenosis, followed by nine (15.2 %) with lumbar spine spondylolisthesis and four (6.7 %) had adjacent level disease. 28 (47.4 %) were scared of surgery, fifteen (25.4 %) claimed that they are too old for surgery and nine (15.2 %) were not ready.Findings from this study outlined that patients lack information about the spinal surgery. Patients education about spine surgery is needed.

Effectiveness of Acceptance and Commitment Therapy (ACT) for the Management of Postsurgical Pain: Study Protocol of a Randomized Controlled Trial (SPINE-ACT Study).

Research on the use of Acceptance and Commitment Therapy (ACT) for patients with degenerative lumbar pathology awaiting surgery are limited. However, there is evidence to suggest that this psychological therapy may be effective in improving pain interference, anxiety, depression, and quality of life. This is the protocol for a randomized controlled trial (RCT) to evaluate the effectiveness of ACT compared to treatment as usual (TAU) for people with degenerative lumbar pathology who are candidates for surgery in the short term. A total of 102 patients with degenerative lumbar spine pathology will be randomly assigned to TAU (control group) or ACT + TAU (intervention group). Participants will be assessed after treatment and at 3-, 6-, and 12-month follow-ups. The primary outcome will be the mean change from baseline on the Brief Pain Inventory (pain interference). Secondary outcomes will include changes in pain intensity, anxiety, depression, pain catastrophizing, fear of movement, quality of life, disability due to low back pain (LBP), pain acceptance, and psychological inflexibility. Linear mixed models will be used to analyze the data. Additionally, effect sizes and number needed to treat (NNT) will be calculated. We posit that ACT may be used to help patients cope with the stress and uncertainty associated with their condition and the surgery itself.

Does Order of Operation Matter in Patients Who Have Concomitant Hip and Spine Pathology?

BackgroundIn patients, who have coexisting lumbar spine and degenerative hip disease, there remains uncertainty regarding whether hip or spine surgery should be performed first. We hypothesized that undergoing total hip arthroplasty (THA) would protect against subsequent lumbar spine surgery (LSS) in patients who have ‘hip-spine syndrome.’ MethodsA retrospective cohort study was performed from 2013 to 2021 on patients who had radiographically–confirmed hip osteoarthritis and degenerative lumbar spine pathology, evaluated separately in spine and arthroplasty clinics prior to surgical intervention. Included patients ultimately underwent THA and/or LSS. The primary outcome was survivorship free of LSS or THA after the other was initially performed. ResultsOf 256 patients, 206 (80.5%) underwent THA first. Only 14 of 206 (6.8%) who underwent THA required subsequent LSS, while 31 of 50 (62%) who underwent LSS required subsequent THA, (P < .001). At 5 years, there was 93.9% survivorship-free of LSS in the THA first group, compared to 44.7% survivorship-free of subsequent THA in the LSS group. Multivariate analyses showed that patients who had THA first had lower odds of undergoing subsequent surgery (odds ratio [OR]: 0.61, CI: 0.52-0.70, P < .001) compared to those who underwent LSS first. Additionally, those who have higher initial Kellgren-Lawrence grade hip osteoarthritis had lower odds (OR: 0.94, CI: 0.89-0.99, P = .04), and those who have progressive neurologic deficits (OR: 2.64, CI: 1.89-3.7, P < .001) and neurogenic claudication (OR: 1.15, CI: 1.06-1.24, P = .001) had increased odds of undergoing subsequent LSS. ConclusionPatients with ‘hip-spine syndrome’ may receive more initial benefit from undergoing THA, potentially reducing the subsequent need for LSS. The exceptions were those patients who had lower-severity hip osteoarthritis and symptoms of major spinal stenosis.

Does decompression adjacent to arthrodesis in the lumbar spine predispose patients to adjacent segment degeneration and disease: A retrospective analysis

BackgroundThe treatment for multi-level spinal stenosis in the setting of single-level instability is a common operative scenario for surgeons who treat degenerative lumbar spine pathology. However, there is conflicting evidence regarding the inclusion of adjacent “stable” levels in the arthrodesis construct because of the potential for iatrogenic instability placed on those segments with decompressive laminectomy alone. This study aims to determine whether decompression adjacent to arthrodesis in the lumbar spine is a risk factor for adjacent segment disease (AS Disease). MethodsA retrospective analysis identified consecutive patients over a three-year period who underwent single-level posterolateral lumbar fusion (PLF) in the setting of single or multi-level spinal stenosis. Patients were required to have a minimum of two-year follow-up. AS Disease was defined as the development of new radicular symptoms referable to a motion segment adjacent to the lumbar arthrodesis construct. The incidence of AS Disease and reoperation rates were compared between cohorts. Results133 patients met the inclusion criteria with an average follow-up of 54 months. Fifty-four patients had a PLF with adjacent segment decompression, and 79 underwent a single-segment decompression and PLF. 24.1% (13/54) of patients who had a PLF with adjacent level decompression developed AS Disease resulting in a 5.5% (3/54) reoperation rate. 15.2% (12/79) of patients who did not receive an adjacent level decompression developed AS Disease resulting in a reoperation rate of 7.5% (6/79). There was neither a significantly higher rate of AS Disease (p = 0.26) nor reoperation (p = 0.74) between the cohorts. ConclusionsDecompression adjacent to single-level PLF was not associated with an increased rate of AS Disease relative to single-level decompression and PLF.

Nonsteroidal anti-inflammatory drugs (NSAID) do not increase blood loss or the incidence of postoperative epidural hematomas when using minimally invasive fusion techniques in the degenerative lumbar spine.

Nonsteroidal anti-inflammatory drugs (NSAID) are essential in surgeons' armamentarium for pain relief and antiphlogistic effects. However, spine surgeons are concerned about the drugs' impact on coagulation, fearing hemodynamic instability due to blood loss and neurological complications due to postoperative hematoma. Furthermore, there are no clear guidelines for the use of these drugs. In this retrospective subgroup analysis of a prospective observational study, we investigated 181 patients who underwent minimally invasive spinal fusions in degenerative lumbar spine pathologies. 83 patients were given NSAID perioperatively, 54 of which were female and 29 male. Of these patients who took NSAID, 39 were on NSAID until at least one day before surgery or perioperatively, whilst the others discontinued their NSAID medication at least three days before surgery. Differences in perioperative blood loss, as well as complication rates between patients with and without NSAID treatment, were investigated. A significantly higher amount of blood loss during surgery and the monitoring period was encountered in patients whose spine was fused in more than one level, regardless of whether NSAID medication was taken or not and up until what point. Furthermore, it was found that taking NSAID medication had no effect on the incidence of postoperative epidural hematomas. Perioperatively taking NSAID medication does not increase blood loss or the incidence of postoperative hematoma in patients undergoing minimally invasive lumbar spinal fusion surgery.

23. Understanding the influence of prior positive COVID-19 infection on 90-day outcomes following elective lumbar spine surgery

BACKGROUND CONTEXTThe COVID-19 pandemic has radically impacted and transformed surgical practice over the past couple of years. While a significant proportion of research has rightfully focused on prevention and/or treatment of acutely infected COVID-19 patients, little is known about how a prior history of a positive COVID-19 infection (ie, recovered patients) influences outcomes following major elective surgeries.PURPOSEThe purpose of the current study was to study whether previous positive COVID-19 infection has an impact on 90-day medical and surgical complication rates following elective lumbar spine surgeries.STUDY DESIGN/SETTINGRetrospective cohort utilizing large all-payer database.PATIENT SAMPLEThis study included 49,639 patients undergoing elective lumbar spine surgery between 2019 and 2021.OUTCOME MEASURESNinety-day medical and surgical complication rates.METHODSThe 2019 to 2021 PearlDiver Mariner Database, an all-payer claims database, was used to identify patients undergoing elective 1- to 2-level primary posterior/anterior/combined fusions or 1- to 2-level laminectomies for degenerative lumbar spine pathologies and 1- to 2-level primary microdiscectomies for herniated discs. Patients undergoing fusion for fracture, malignancy, infection and/or those undergoing revision procedures were excluded from the study. The study group was divided into two cohorts — those who had a prior history of a COVID-19 infection within the 6 months before surgery and those who were not infected by the virus. Patients who had a positive coded COVID-19 status on the day of surgery were excluded from the analysis. Multivariate logistic regression analyses were used to assess the impact of prior COVID-19 infection on 90-day medical and surgical complication rates, while controlling for baseline demographics (age, gender, payor type/insurance) and clinical characteristics (Charlson comorbidity index, type of surgery, and prior ventilator dependence).RESULTSA total of 49,639 patients undergoing elective lumbar spine surgery between 2019 and 2021 were included in the study, out of which 150 patients (0.3%) had had a positive COVID-19 status and/or infection in the 6 months prior to the surgery. After adjusting for baseline demographics and clinical characteristics, patients with a prior history of COVID-19 infection were more likely to experience cardiac complications (3.3% vs 1.1%, OR 2.75; p=0.021), thromboembolic complications (6.0% vs 2.3%, OR 2.35; p=0.014) and sepsis (5.3% vs 2.0%, OR 2.31; p=0.024) within 90 days of the index surgery.CONCLUSIONSBased on a national retrospective review of patients undergoing elective lumbar spine surgery, it appears that having harbored a positive COVID-19 infection in the 6 months prior to surgery is associated with higher risks of experiencing thromboembolic events, sepsis and acute myocardial infarctions or acute congestive heart failure. The findings of the study support the need of careful postoperative care monitoring and/or risk-stratification of prior COVID-19 patients.FDA DEVICE/DRUG STATUSThis abstract does not discuss or include any applicable devices or drugs.

Lordosis loss in degenerative spinal conditions.

To establish whether common degenerative lumbar spine conditions have a predictable sagittal profile and associated range of lordosis. The spinopelvic balance of a normal population and normal ranges are well described in the literature. There is also evidence that certain degenerative conditions can lead to a preponderance of loss of lordosis at specific spinal levels. There is limited literature on the range and magnitude of loss of lordosis for known degenerative lumbar spine pathologies. A retrospective analysis of prospectively obtained radiographs from a dual surgeon database was performed and imaging analysed for spinopelvic parameters. Degenerative conditions studied were; Lumbar degenerative spondylolisthesis (L3/4 and L4/5 analysed separately), L5/S1 degenerative disc disease, L5/S1 isthmic spondylolisthesis. Pelvic incidence, sacral slope, pelvic tilt, segmental and global lumbar lordosis, vertebral lordosis and lumbar vertical axis were measured. The range of change in segmental lordosis was normally distributed for all studied degenerative spinal conditions except L5/S1 isthmic spondylolisthesis. L5/S1 degenerative disc disease affected younger adults (mean age 37), whilst degenerative spondylolisthesis at L3/4 and L4/5 affected older adults (mean ages 69.5 and 68.9 respectively). Removing an outlying high-grade L5/S1 isthmic spondylolisthesis made the data distribution approach a normal distribution. Most degenerative spinal pathologies cause a normally distributed spectrum of deformity which should be addressed and corrected with a tailored, individualised surgical plan for each patient. Universal treatment recommendations should be interpreted with caution.

Predictors of Complications and Unfavorable Outcomes of Minimally Invasive Surgery Treatment in Elderly Patients With Degenerative Lumbar Spine Pathologies (Case Series).

IntroductionThe use of minimally invasive surgery (MIS) results in fewer adverse and more improved outcomes. However, the literature data describing the factors increasing the number of complications, reoperation frequency and unscheduled re-hospitalizations in older patients after MIS are contradictory. In this study, a large number of patients was investigated for the complications of minimally invasive surgical treatment of degenerative disease of the lumbar spine in older patients. The objective of the study was to determine the predictors of unfavorable outcomes in such patients.Materials and Methods1,013 patients underwent MIS (decompression alone, TLIF, LLIF, ALIF) in 2013-2017. All operations were performed with the participation of the authors (neurosurgeons). The patient's average age was 66. The following data were collected: BMI; CCI; presence of postoperative complications according to the Dindo-Clavien classification; unplanned readmission at 90 days; hospital length of stay (LOS); surgical complexity (low, intermediate, and high); surgical time; and risk factors. The cumulative reoperation rate was determined at 5-years follow-up.ResultsA total of 256 patients suffered a complication (25.2%), 226 classified as mild (grade I, II, IIIA), and 30 - as severe (IIIB, IVA). Such factors as the surgical complexity, BMI > 30, surgical time, number of operated levels were associated with a significant risk of developing a complication. For patients with and without complications, LOS was 9.3 and 6.3 days, respectively (p < 0.0001), the unplanned readmission rate was 1.3%. 104 patients underwent 133 revision operations. The 5-year cumulative reoperation rate was 15.2%, and the reoperation index was 12.1%. The CCI had no statistically significant effect on the complication incidence after MIS. A higher risk of complications was found in patients who underwent intermediate-complexity surgery (MIS TLIF) compared with uncompounded (decompression alone) and more complex (MIS LLIF, MIS ALIF) surgical procedures (p < 0.001 and p = 0.001, respectively).ConclusionA register of postoperative complications is an important tool for health quality assessment and choosing the best surgical option that helps to establish measures to reduce such complications. Using MIS for the treatment of elderly patients reduces the number of severe complications.

Data-driven phenotyping of preoperative functional decline patterns in patients undergoing lumbar decompression and lumbar fusion using smartphone accelerometry.

Treatment of degenerative lumbar spine pathologies typically escalates to surgical intervention when symptoms begin to significantly impair patients' functional status. Currently, surgeons rely on subjective patient assessments through patient-reported outcome measures to estimate the decline in patient wellness and quality of life. In this analysis, the authors sought to use smartphone-based accelerometry data to provide an objective, continuous measurement of physical activity that might aid in effective characterization of preoperative functional decline in different lumbar spine surgical indications. Up to 1 year of preoperative activity data (steps taken per day) from 14 patients who underwent lumbar decompression and 15 patients who underwent endoscopic lumbar fusion were retrospectively extracted from patient smartphones. A data-driven algorithm was constructed based on 10,585 unique activity data points to identify and characterize the functional decline of patients preceding surgical intervention. Algorithmic estimation of functional decline onset was compared with reported symptom onset in clinical documentation across patients who presented acutely (≤ 5 months of symptoms) or chronically (> 5 months of symptoms). The newly created algorithm identified a statistically significant decrease in physical activity during measured periods of functional decline (p = 0.0020). To account for the distinct clinical presentation phenotypes of patients requiring lumbar decompression (71.4% acute and 28.6% chronic) and those requiring lumbar fusion (6.7% acute and 93.3% chronic), a variable threshold for detecting clinically significant reduced physical activity was implemented. The algorithm characterized functional decline (i.e., acute or chronic presentation) in patients who underwent lumbar decompression with 100% accuracy (sensitivity 100% and specificity 100%), while characterization of patients who underwent lumbar fusion was less effective (accuracy 26.7%, sensitivity 21.4%, and specificity 100%). Adopting a less-permissive detection threshold in patients who underwent lumbar fusion, which rendered the algorithm robust to minor fluctuations above or below the chronically decreased level of preoperative activity in most of those patients, increased functional decline classification accuracy of patients who underwent lumbar fusion to 66.7% (sensitivity 64.3% and specificity 100%). In this study, the authors found that smartphone-based accelerometer data successfully characterized functional decline in patients with degenerative lumbar spine pathologies. The accuracy and sensitivity of functional decline detection were much lower when using non-surgery-specific detection thresholds, indicating the effectiveness of smartphone-based mobility analysis in characterizing the unique physical activity fingerprints of different lumbar surgical indications. The results of this study highlight the potential of using activity data to detect symptom onset and functional decline in patients, enabling earlier diagnosis and improved prognostication.

Stability in Direct Lateral vs Direct Anterior Total Hip Arthroplasty in the Context of Lumbar Spinal Fusion.

Lumbar spinal fusion (LSF) may increase the risk of dislocation in patients who have undergone total hip arthroplasty (THA), especially when the LSF was done before the THA. Most publications evaluated patients who had undergone THA using a posterior approach to the hip, yet there are little data on the influence of other surgical approaches. The goal of this study was to evaluate the risk of THA dislocation with anterior supine-based surgical approaches to the hip in patients who have undergone surgical management of concurrent hip and spine pathology. Patients older than 18 years who underwent an LSF and THA using a supine approach-either direct anterior (DA) or direct lateral (DL)-between 2000 and 2018 were identified. Only standard bearings (28-32-36-40 mm) were used. The dislocation rate was determined in this cohort. A subsequent analysis was conducted, stratifying patients based on the order in which they received the LSF or THA. A total of 582 surgical hip-spine patients were retrospectively identified and included in the cohort. Of total, 332 patients (57.0%) received an LSF before the THA; 250 (43.0%) had the fusion after a primary hip replacement. There were 143 patients (24.6%) in the DA group and 439 (75.4%) in the DL group. Overall, there were five dislocations (0.9%) in the entire cohort. In patients with simultaneous degenerative hip and lumbar spine pathology, anterior supine-based approaches demonstrate a low (<1%) risk of instability. Given the small number of total dislocation events (n = 5), additional analysis is warranted to assess the effect of different anterior approaches (DA versus DL) or timing of lumbar spinal surgery (before or after THA). Level III.

The influence of comorbidity on the results of surgical treatment of elderly and senile patients with degenerative lumbar spinal stenosis

Objective. To analyze the influence of somatic comorbidity on the results of surgical treatment of elderly and senile patients with degenerative lumbar spinal stenosis.Material and Methods. The study design corresponds to a single-center non-randomized retrospective cohort study with level 3 evidence (OCEBM Levels of Evidence Working Group. The Oxford 2011 Levels of Evidence). The influence of somatic comorbidity on quality of life after surgery for degenerative lumbar spinal stenosis was analyzed in 962 patients 60–85 years old. Analysis and evaluation of the results of the study was carried out in two groups of patients with radicular compression syndrome: Group 1 (less than 5 points according to White – Panjabi criteria) included 625 (65%) patients, and Group 2 (5 or more points according to White – Panjabi criteria) – 337 (35%) patients.Results. Body mass index of patients in Group 1 was statistically significantly lower than in Group 2. Repeated surgical interventions performed during the first year after the primary operation were statistically significantly more frequent in Group 1, and those performed after 3–4 years were more frequent in Group 2 (BMI ≥ 30) due to the development of adjacent level disease. In obese patients, the duration of surgery, blood loss and postoperative hospital stay are statistically significantly increased. One year after surgery, a statistically significant negative effect of increase in BMI on the parameters of back pain, lower limb pain, functional adaptation, and quality of life was revealed in both groups of patients. No association of obesity and complication rates was noted. In Group 2, the incidence of adjacent level disease 2–5 years after the primary operation was higher in patients with BMI ≥ 30 compared with patients with BMI &lt; 30 and with patients in Group 1. It was found that somatic comorbidity and the age of patients statistically significantly prolonged postoperative hospital stay in Group 1 and did not affect its duration in Group 2. No effect of the comorbidity index on the quality of life was noted. Osteoporosis was statistically significantly associated with an increase in the frequency of technical complications during surgery (malposition of pedicle screws, cage migration, and damage to the vertebral endplates).Conclusion. Obesity is statistically significantly associated with an increase in postoperative hospital stay, surgery duration and blood loss, and is a predictor of the development of instability of the spinal motion segment and adjacent level disease. Obese patients have higher levels of back and lower limb pain and worse quality of life parameters after surgical interventions than patients with normal body weight. When using minimally invasive technologies in the surgical treatment of degenerative lumbar spine pathology, the number of complications in obese patients is not higher than in patients with normal body weight. The effect of comorbidity on the results of minimally invasive surgery for degenerative lumbar pathology was not detected. Osteoporosis affects the frequency of technical complications during surgery.

Surgical Treatment of Patients With Dual Hip and Spinal Degenerative Disease: Effect of Surgical Sequence of Spinal Fusion and Total Hip Arthroplasty on Postoperative Complications.

Retrospective study. To determine how lumbar spinal fusion-total hip arthroplasty (LSF-THA) operative sequence would affect THA outcomes. Outcomes following THA in patients with a history of lumbar spinal degenerative disease and fusion are incompletely understood. The PearlDiver Research Program (http://www.pearldiverinc.com) was used to identify patients undergoing primary THA. Patients were divided into four cohorts: 1) Primary THA without spine pathology, 2) remote LSF prior to hip pathology and THA, and patients with concurrent hip and spinal pathology that had 3) THA following LSF, and 4) THA prior to LSF. Postoperative complications and opioid use were assessed with multivariable logistic regression to determine the effect of spinal degenerative disease and operative sequence. Between 2007 and 2017, 85,595 patients underwent primary THA, of whom 93.6% had THA without lumbar spine degenerative disease, 0.7% had a history of remote LSF, and those with concurrent hip and spine pathology, 1.6% had THA prior to LSF, and 2.4% had THA following LSF. Patients with hip and lumbar spine pathology who underwent THA prior to LSF had significantly higher rates of dislocation (aOR = 2.46, P < 0.0001), infection (aOR = 2.65, P < 0.0001), revision surgery (aOR = 1.91, P < 0.0001), and postoperative opioid use at 1 month (aOR: 1.63, P < 0.001), 3 months (aOR = 1.80, P < 0.001), 6 months (aOR: 2.69, P < 0.001), and 12 months (aOR = 3.28, P < 0.001) compared with those treated with THA following LSF. Patients with degenerative hip and lumbar spine pathology who undergo THA prior to LSF have a significantly increased risk of postoperative dislocation, infection, revision surgery, and prolonged opioid use compared with THA after LSF. Surgeons should consider the surgical sequence of THA and LSF on outcomes for patients with this dual pathology. Shared decision making between patients, spine surgeons, and arthroplasty surgeons is necessary to optimize outcomes in patients with concomitant hip and spine pathology. 3.

Outcomes Following Posterior Lumbar Fusion in Patients with Polycythemia Vera

Polycythemia vera (PV) is a chronic myeloproliferative neoplasm that is associated with increased risk for venous and arterial thromboembolism. The aim of this study was to evaluate outcomes following elective posterior lumbar fusion (PLF) and/or posterior interbody fusion (PLIF) among patients with PV. Using PearlDiver retrospective national database, Medicare patients <85 years old who underwent elective primary PLF (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] code 81.07) and/or PLIF (ICD-9-CM code 81.08) for degenerative lumbar spine pathologies during 2006-2013 were identified. Patients included in the PLF and/or PLIF cohort were separated into patients with a prior diagnosis of PV (ICD-9-CM code 238.4) and a control cohort of patients without PV. Comparisons of postoperative outcomes were made between the PV patient group and matched control group. Significance was set at 0.05. Selected study participants included 1491 patients with PV and 29,056 patients in the matched control group. Patients with PV had a significantly increased rate of 90-day acute pulmonary embolism (1.9% vs. 1.2%, odds ratio [OR] 1.65, 95% confidence interval [CI] 1.10-2.38, P= 0.010), 90-day lower extremity deep vein thrombosis (3.4% vs. 1.9%, OR 1.81, 95% CI 1.33-2.40, P < 0.001), and 1-year diagnosis of surgical site infection (5.4% vs. 4.2%, OR 1.30, 95% CI 1.02-1.63, P= 0.027) compared with patients without PV. Nonetheless, PV was not associated with other major medical complications, including stroke, myocardial infarction, and mortality, following PLF and/or PLIF. Patients with PV undergoing elective PLF and/or PLIF have a significantly increased risk for pulmonary embolism, lower extremity deep vein thrombosis, and surgical site infection.

Association Between Lumbar Spinal Degeneration and Anatomic Pelvic Parameters.

Retrospective cohort study. The objective was to prove the association between anatomic pelvis parameters and specific types of lumbar spinal degeneration. Different spinopelvic sagittal profile types are suggested to be associated with specific degenerative lumbar spine pathologies. Because pelvic morphology plays a key role defining the spinal shape as well as its load and function it thereby potentially predisposes the development of spinal degeneration. Patients with symptomatic lumbar spinal degeneration who were surgically treated in 2 spine departments from March 2011 until August 2016 were included in this retrospective analysis. Single-level degenerative pathologies were classified as lumbar disc herniation (LDH), degenerative disc disease (DDD), lumbar spinal stenosis (LSS), and degenerative spondylolisthesis (DSPL). The constant anatomic pelvic parameters pelvic incidence (PI), pelvic radius (PR), and sacral table angle (STA) were assessed in lateral radiographs of the lumbar spine and compared between the pathologies. In total, 249 patients were assigned to the LDH (n=73), DDD (n=67), LSS (n=42), and DSPL (n=67) groups. Group comparisons revealed significant differences in the anatomic pelvic parameters PR (LDH, 139.5±10.8 mm; DDD, 135.9±14.0 mm; LSS, 127.8±14.3 mm; DSPL, 135.8±12.7 mm; P<0.001), PI (LDH, 53.1±10.0 degrees; DDD, 50.0±9.9 degrees; LSS, 54.5±9.6 degrees; DSPL, 57.1±10.8 degrees; P=0.001), and STA (LDH, 95.3±12.7 degrees; DDD, 105.4±9.0 degrees; LSS, 105.9±11.5 degrees; DSPL, 98.6±9.5 degrees; P<0.001). Post hoc tests indicated significant differences between the PR of the LSS group and that of all other subgroups (P<0.012), the PI of the DDD group and that of DSPL (P<0.001), and the STA of the LDH/DSPL groups and that of the LSS/DDD group (P<0.005). We found all the constant anatomic parameters to be specific for distinct types of degeneration, suggesting pelvis shape is a predisposing factor for their development. Level III.

Surgical treatment of multilevel lumbar vertebral canal stenosis using dynamic stabilization. Multicenter study

Purpose: to compare the results of surgical treatment of patients with multilevel lumbar vertebral canal stenosis. Patients and methods. Prospective randomized multicenter study included 71 patients aged 41 - 79 years. In the 1st group of patients (n=38) a standard wide decompression of the spinal canal, transpedicular fixation of one clinically and roentgenologically significant spinal motion segment using rigid stabilization and interbody fusion was performed. In the 2nd group (n=33) microdecompression of the spinal canal, transpedicular fixation of one clinically and roentgenologically significant segment using the rods of nitinol transpedicular device. The results were assessed by the pain VAS, ODI and SF-36 questionnaires, roentgenologic, CT and MRI data. Results. Mean follow up made up 1.5 years, the maximum one - 3.0 years. Significant pain relief and im- provement in the quality of life as compared with the preoperative level was reported for both groups. No sig- nificant difference between the groups was observed. Functional roentgenograms showed within 5° (4.2 - 6.5°) preservation of motion in the stabilized segment only in patients from the 2nd group. Adjacent segment pathology in 12 months after operation was diagnosed only in 1 patient from the 1st group. Conclusion. Preliminary results allow considering the dynamic transpedicular fixation using nitinol rods as an effective surgical technique for the treatment of degenerative lumbar spine pathology.

338 Variation in the Cost/Benefit of Spine Surgery at the Individual Patient Level

Abstract INTRODUCTION Currently, specific spine treatments are deemed altogether cost-effective vs not based on group average costs and group average health benefit. These approaches ignore that certain treatments may be highly cost-effective in subsets of patients while group averages suggest otherwise, leading to disadvantageous policy for some highly valuable spine care. We evaluate the variability in outcomes and cost for patients undergoing surgery for degenerative lumbar spine pathology at the individual patient-level. METHODS Retrospective analysis of prospective longitudinal spine registry data was conducted. Baseline and postoperative 1-year patient-reported outcomes (PROs) were recorded. Previously published MCID for ODI (14.9) was used. Back-related resource utilization and quality-adjusted life years (QALYs) were assessed. Variations in outcomes and cost were analyzed at population level and at the individual-patient level. RESULTS &gt;Total 1454 patients were analyzed. There was significant improvement in PROs at postoperative 1-year (P &lt; 0.0001). For patients demonstrating health benefit at population level, 12.5%, n = 182 of patients experienced no gain from surgery and 38%, n = 554 failed to achieve MCID. Mean 1-year QALY-gained was 0.29,18% of patients failed to report gain in QALY. For patients with 2-year follow-up, surgery resulted in 0.62 QALY-gained at average direct cost of $28,953. A wide variation in both QALY-gained and cost was observed. CONCLUSION Spine treatments that on average are cost-effective may have wide variability in value at the individual patient-level. The variability demonstrated here represents an opportunity, through registries, to identify specific care that may be less effective, and refine patient-specific care delivery and indications to drive overall group-level treatment value.

The Influence of Pelvic Incidence and Lumbar Lordosis Mismatch on Development of Symptomatic Adjacent Level Disease Following Single-Level Transforaminal Lumbar Interbody Fusion.

Annual incidence of symptomatic adjacent level disease (ALD) following lumbar fusion surgery ranges from 0.6% to 3.9% per year. Sagittal malalignment may contribute to the development of ALD. To describe the relationship between pelvic incidence-lumbar lordosis (PI-LL) mismatch and the development of symptomatic ALD requiring revision surgery following single-level transforaminal lumbar interbody fusion for degenerative lumbar spondylosis and/or low-grade spondylolisthesis. All patients who underwent a single-level transforaminal lumbar interbody fusion at either L4/5 or L5/S1 between July 2006 and December 2012 were analyzed for pre- and postoperative spinopelvic parameters. Using univariate and logistic regression analysis, we compared the spinopelvic parameters of those patients who required revision surgery against those patients who did not develop symptomatic ALD. We calculated the predictive value of PI-LL mismatch. One hundred fifty-nine patients met the inclusion criteria. The results noted that, for a 1° increase in PI-LL mismatch (preop and postop), the odds of developing ALD requiring surgery increased by 1.3 and 1.4 fold, respectively, which were statistically significant increases. Based on our analysis, a PI-LL mismatch of >11° had a positive predictive value of 75% for the development of symptomatic ALD requiring revision surgery. A high PI-LL mismatch is strongly associated with the development of symptomatic ALD requiring revision lumbar spine surgery. The development of ALD may represent a global disease process as opposed to a focal condition. Spine surgeons may wish to consider assessment of spinopelvic parameters in the evaluation of degenerative lumbar spine pathology.

Lumbar multifidus muscle degenerates in individuals with chronic degenerative lumbar spine pathology.

Histological and cell-level changes in the lumbar musculature in individuals with chronic lumbar spine degenerative conditions are not well characterized. Although prior literature supports evidence of changes in fiber type and size, little information exists describing the tissue quality and biology of pathological features of muscle in this population. The purpose of this study was to quantify multifidus tissue composition and structure, inflammation, vascularity, and degeneration in individuals with chronic degenerative lumbar spine pathology. Human multifidus biopsies were acquired from 22 consecutive patients undergoing surgery for chronic degenerative lumbar spine pathology. Relative fractions of muscle, adipose, and extracellular matrix were quantified along with muscle fiber type and cross-sectional area (CSA) and markers of inflammation, vascularity, satellite cell density, and muscle degeneration. On average, multifidus biopsies contained 48.5% muscle, 11.7% adipose tissue, and 26.1% collagen tissue. Elevated inflammatory cell counts (48.5 ± 30.0 macrophages/mm2 ) and decreased vascularity (275.6 ± 69.4 vessels/mm2 ) were also observed compared to normative values. Satellite cell densities were on average 13 ± 9 cells per every 100 muscle fibers. Large fiber CSA (3,996.0 ± 1,909.2 µm2 ) and a predominance of type I fibers (61.8 ± 18.0%) were observed in addition to evidence of pathological degeneration-regeneration cycling (18.8 ± 9.4% centrally nucleated fibers, and 55.2 ± 24.2% of muscle regions containing degeneration). High levels of muscle degeneration, inflammation, and decreased vascularity were commonly seen in human multifidus biopsies of individuals with lumbar spine pathology in comparison to normative data. Evidence of active muscle degeneration suggests that changes in muscle tissue are more complex than simple atrophy. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2700-2706, 2017.

Evaluation of a Hybrid Dynamic Stabilization and Fusion System in the Lumbar Spine: A 10 Year Experience.

Introduction: The development of adjacent-segment disease is a recognized consequence of lumbar fusion surgery. Posterior dynamic stabilization, or motion preservation, techniques have been developed which theoretically decrease stress on adjacent segments following fusion. This study presents the experience of using a hybrid dynamic stabilization and fusion construct for degenerative lumbar spine pathology in place of rigid arthrodesis.Methods: A clinical cohort investigation was conducted of 66 consecutive patients (31 female, 35 male; mean age: 53 years, range: 25 – 76 years) who underwent posterior lumbar instrumentation with the Dynesys Transition Optima (DTO) implant (Zimmer-Biomet Spine, Warsaw, IN) hybrid dynamic stabilization and fusion system over a 10-year period. The median length of follow-up was five years. DTO consists of pedicle screw fixation coupled to a rigid rod as well as a flexible longitudinal connecting system. All patients had symptoms of back pain and neurogenic claudication refractory to non-surgical treatment. Patients underwent lumbar arthrodesis surgery in which the hybrid system was used for stabilization instead of arthrodesis of the stenotic adjacent level.Results: Indications for DTO instrumentation were primary degenerative disc disease (n = 52) and failed back surgery syndrome (n = 14). The most common dynamically stabilized and fused segments were L3-L4 (n = 37) and L5-S1 (n = 33), respectively. Thirty-eight patients (56%) underwent decompression at the dynamically stabilized level, and 57 patients (86%) had an interbody device placed at the level of arthrodesis. Complications during the follow-up period included a single case of screw breakage and a single case of pseudoarthrosis. Ten patients (15%) subsequently underwent conversion of the dynamic stabilization portion of their DTO instrumentation to rigid spinal arthrodesis.Conclusion: The DTO system represents a novel hybrid dynamic stabilization and fusion construct. This 10-year experience found the device to be highly effective as well as safe. The technique may serve as an alternative to multilevel arthrodesis. Implantation of a motion-preserving dynamic stabilization device immediately adjacent to a fused level instead of extending a rigid construct may reduce the subsequent development of adjacent-segment disease in this patient population.