Sigurd Berven

• University of California, San Francisco

Background: Lumbar lordosis distribution has become a pivotal factor in re-establishing the foundational alignment of the lumbar spine. This can directly influence overall sagittal alignment, leading to improved long-term outcomes for patients. Despite the wide availability of hyperlordotic stock cages intended to achieve optimal postoperative ali...

Study design Clinical case series. Objective To describe the cause, treatment and outcome of 6 cases of perioperative spinal cord injury (SCI) in high-risk adult deformity surgery. Setting Adult spinal deformity patients were enrolled in the multi-center Scoli-RISK-1 cohort study. Methods A total of 272 patients who underwent complex adult defor...

Study Design Prospective multicenter database post-hoc analysis. Objectives Opioids are frequently prescribed for painful spinal conditions to provide pain relief and to allow for functional improvement, both before and after spine surgery. Amidst a current opioid epidemic, it is important for providers to understand the impact of opioid use and i...

Purpose To define the prevalence, characteristics, and treatment approach for proximal junction failure secondary to odontoid fractures in patients with prior C2-pelvis posterior instrumented fusions (PSF). Methods A single institution’s database was queried for multi-level fusions (6+ levels), including a cervical component. Posterior instrumenta...

Purpose To review existing classification systems for degenerative spondylolisthesis (DS), propose a novel classification designed to better address clinically relevant radiographic and clinical features of disease, and determine the inter- and intraobserver reliability of this new system for classifying DS. Methods The proposed classification sys...

Objective: Generally, anterior lumbar interbody fusion (ALIF) was believed superior to transforaminal lumbar interbody fusion (TLIF) in induction of fusion. However, many studies have reported comparable results in lumbosacral fusion rate between the two approaches. This study aimed to evaluate the realistic lumbosacral arthrodesis rates following...

Purpose: To assess recommendations for when adult spinal deformity (ASD) patients may return to athletic activities after surgery. Methods: A web-based survey was administered to members of AO Spine. The survey consisted of surgeon demographic information and questions asking when a patient undergoing a long thoracolumbar fusion (> 5 levels) wit...

Value-based health care is an increasingly important priority in our health care economy and has particular relevance to the field of spine surgery. Value includes a consideration of both quality and cost—the value of a health care intervention is assessed by whether it provides an incremental benefit in outcome to justify an incremental increase i...

Objective: Vertebral osteomyelitis is a rare complication of coccidioidomycosis infection. Surgical intervention is indicated when there is failure of medical management or presence of neurological deficit, epidural abscess, or spinal instability. The relationship between timing of surgical intervention and recovery of neurological function has no...

Study design: Prospective, multicenter, international, observational study. Objective: Identify independent prognostic factors associated with achieving the minimal clinically important difference (MCID) in patient reported outcome measures (PROMs) among adult spinal deformity (ASD) patients ≥60 years of age undergoing primary reconstructive sur...

Objective: In the absence of spinal cord compression, it is unclear if surgery is more effective than radiation treatment for improving functional outcomes in metastatic spinal tumor patients with potentially unstable spines. The authors compared functional status outcomes assessed with Karnofsky Performance Status (KPS) and Eastern Cooperative On...

INTRODUCTION Degenerative spondylolisthesis (DS) with lumbar spinal stenosis (LSS) is commonly treated with decompression and fusion. The LimiFlex Dynamic Sagittal Tether (DST) is an investigational stabilization device for patients with DS and LSS. METHODS Patients with single-level Grade 1 DS with LSS were enrolled in FDA-IDE study (NCT03115983)...

Study design: Multicenter, international prospective study. Objective: This study investigated the clinical outcome up to 2 years after multi-level spinal deformity surgery in the elderly by reporting the minimal clinically important difference (MCID) of EuroQol 5-dimensions (EQ-5D), EQ-VAS, and residential status. Methods: As an ancillary stu...

Background: Assess correlation between preoperative cervical sagittal alignment (T1 slope [T1S] and C2-C7 cervical sagittal vertical axis [cSVA]) and postoperative cervical sagittal balance after posterior cervical laminoplasty. Methods: Consecutive patients who underwent laminoplasty at a single institution with >6 weeks postoperative follow-up...

Purpose To identify independent risk factors, including the Risk Assessment and Prediction Tool (RAPT) score, associated with extended length of stay (eLOS) and non-home discharge following elective multi-level instrumented spine fusion operations for diagnosis of adult spinal deformity (ASD) and lumbar degenerative pathology. Methods Adults who u...

Background: As the opioid epidemic accelerates in the United States, numerous sociodemographic factors have been implicated its development and are, furthermore, a driving factor of the disparities in postoperative pain management. Recent studies have suggested potential associations between the influence of race and ethnicity on pain perception b...

BACKGROUND CONTEXT Degenerative spondylolisthesis (DS) with lumbar spinal stenosis (LSS) is commonly treated with decompression and fusion. The LimiFlex Dynamic Sagittal Tether (DST) is an investigational stabilization device for patients with DS and LSS. PURPOSE The purpose of this study is to assess the clinical and radiographic outcomes of deco...

BACKGROUND CONTEXT Although studies have explored acute opioid use within 30 days after surgery and chronic opioid use longer than 90 days after surgery, the impact of opioid use within the subacute phase of 31-90 days after surgery has not been studied. However, this subacute postoperative period has been identified as a potential predictor of chr...

BACKGROUND CONTEXT Degenerative spondylolisthesis (DS) with lumbar spinal stenosis (LSS) is commonly treated with decompression and fusion. The LimiFlex Dynamic Sagittal Tether (DST) is an investigational stabilization device for patients with DS and LSS. PURPOSE Assess return to work (RTW) and activities of daily living (ADL) receiving either dec...

OBJECTIVE Wound complications are a common adverse event following metastatic spine tumor surgery. Some patients with spinal metastases may first undergo radiation but eventually require spinal surgery because of either cord compression or instability. The authors compared wound complication rates in patients who had undergone surgery for metastati...

Introduction Adjacent segment disease (ASD) of the cervical spine is a common disabling phenomenon that often requires surgical intervention. The goal of this study was to evaluate the economic impact of revision operations for cervical ASD. Methods Consecutive adults who underwent revision cervical spine surgery for ASD at a single institution be...

PurposeAnalyze state databases to determine variables associated with of short-term readmissions and reoperations following thoracolumbar spine fusions for degenerative pathology and spinal deformity.Methods Retrospective study of State Inpatient Database (2005-13, CA, NE, NY, FL, NC, UT). Inclusion criteria: age > 45 years, diagnosis of degenerati...

To assess factors, including RAPT score, predictive of non-home discharges following adult spinal deformity (ASD) operations. Adults who underwent thoracolumbar instrumented fusions to the pelvis for ASD (1/2019–1/2020) were reviewed. Patient demographics, RAPT metrics, hospital length of stay (LOS), operative details, and complications were compar...

Study design: Expert Consensus Study. Objectives: This expert panel was created to establish best practice guidelines to identify and treat patients with poor bone health prior to elective spinal reconstruction. Summary of background data: Currently, no guidelines exist for the management of osteoporosis and osteopenia in patients undergoing s...

BACKGROUND CONTEXT Social media allows millions of users of different geographic, political, socioeconomic and national backgrounds to communicate and exchange information worldwide. The internet and social media use have sky-rocketed in the past 15 years. Seventy-two percent of all adults have used social media to gather health care information. T...

BACKGROUND CONTEXT Discharge location is an important step in the continuum of care for adults who undergo surgery for spinal deformity (ASD). Insight into which patients are at risk for nonhome discharge (acute rehabilitation and skilled nursing facility [SNF]) is essential for preoperative planning and counseling. The Risk Assessment and Predicti...

BACKGROUND CONTEXT Although matching lumbar lordosis (LL) with pelvic incidence (PI) is an important surgical goal for adult spinal deformity (ASD), there is concern that overcorrection may lead to proximal junctional kyphosis (PJK). We introduce the upper instrumented vertebra – femoral angle (UIVFA) as a measure of appropriate postoperative posit...

BACKGROUND CONTEXT Severity of deformity, preoperative disability, and surgical strategies are variable between, and within, centers performing reconstructive surgery for spinal deformity. However, geographic variation in how surgeons manage ASD patients worldwide is unknown. PURPOSE The purpose of this study was to compare the surgical approach a...

Background Context: Patients with adult spinal deformity suffer from disease related disability as measured by the ODI for which surgery can result in significant improvements. Purpose: The purpose of this study was to show the change in overall and individual components of the Oswestry Disability Index (ODI) in patients aged 60 years or older foll...

Study Design Retrospective cohort study. Objective Overcorrection in adult spinal deformity (ASD) surgery may lead to proximal junctional kyphosis (PJK) because of posterior spinal displacement. The aim of this paper is to determine if the L1 position relative to the gravity line (GL) is associated with PJK. Methods ASD patients fused from the lo...

In this chapter, Dr. Chan, Dr. Pennicooke, Dr. Berven, and Dr. Mummaneni discuss the two-surgeon model with a neurosurgeon and an orthopedic spine surgeon. The two-surgeon model is associated with a decrease in blood loss, complication rates, reoperations, surgical site infections, venous thromboembolisms, and urinary tract infections. The foundati...

Study design: International, multi-center, prospective, longitudinal observational cohort. Objective: To assess how new motor deficits affect patient reported quality of life scores after adult deformity surgery. Summary of background data: Adult spinal deformity surgery is associated with high morbidity, including risk of new post-operative m...

OBJECTIVE Radiculopathy from the fractional curve, usually from L3 to S1, can create severe disability. However, treatment methods of the curve vary. The authors evaluated the effect of adding more levels of interbody fusion during treatment of the fractional curve. METHODS A single-institution retrospective review of adult patients treated for sc...

Objective: The aim of this study was to investigate whether fat infiltration of the lumbar multifidus (LM) muscle affects revision surgery rates for adjacent-segment degeneration (ASD) after L4-5 transforaminal lumbar interbody fusion (TLIF) for degenerative spondylolisthesis. Methods: A total of 178 patients undergoing single-level L4-5 TLIF fo...

Background: Minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) is a surgical technique frequently used to treat symptomatic lumbar spondylolisthesis. We aim to investigate the safety and efficacy of using a biplanar expandable cage in the treatment of symptomatic lumbar spondylolisthesis using a MIS TLIF approach. Methods: A re...

Background: The treatment of pseudarthrosis after transforaminal lumbar interbody fusion (TLIF) can be challenging, particularly when anterior column reconstruction is required. There are limited data on TLIF cage removal through an anterior approach. Objective: To assess the safety and efficacy of anterior lumbar interbody fusion (ALIF) as a tr...

Objective: In this study, the authors' aim was to investigate whether obesity affects surgery rates for adjacent-segment degeneration (ASD) after transforaminal lumbar interbody fusion (TLIF) for spondylolisthesis. Methods: Patients who underwent single-level TLIF for spondylolisthesis at the University of California, San Francisco, from 2006 to...

Objective: During the COVID-19 pandemic, quaternary-care facilities continue to provide care for patients in need of urgent and emergent invasive procedures. Perioperative protocols are needed to streamline care for these patients notwithstanding capacity and resource constraints. Methods: A multidisciplinary panel was assembled at the Universit...

Study design: Retrospective study. Objective: The aim of this study was to investigate whether there is an association between revision surgery rates for adjacent segment degeneration (ASD) and Roussouly type after L4-5 transforaminal lumbar interbody fusion (TLIF) for spondylolisthesis. Summary of background data: Revision surgery for ASD is...

OBJECTIVE Anterior lumbar interbody fusion (ALIF) is a powerful technique that provides wide access to the disc space and allows for large lordotic grafts. When used with posterior spinal fusion (PSF), the procedures are often staged within the same hospital admission. There are limited data on the perioperative risk profile of ALIF-first versus PS...

The clamshell thoracotomy is often used to access both hemithoraxes and the mediastinum simultaneously for cardiothoracic pathology, but this technique is rarely used for the excision of spinal tumors. We describe the use of a clamshell thoracotomy for en bloc excision of a 3-level upper thoracic chordoma in a 20-year-old patient. The lesion involv...

BACKGROUND CONTEXT It is known that upper instrumented vertebrae (UIV) position relative to sagittal vertical axis (SVA) is associated with PJK. Over correction of the lumbar spine, resulting in posterior displacement of L1 relative to the GL, may be associated with PJK. PURPOSE Patients who are over corrected with hyper-lordotic spines may develo...

BACKGROUND CONTEXT Paraspinal muscle fat infiltration has been shown to be associated with back pain. However, it is unclear if fat infiltration of the lumbar multifidus (LM) increases the rate of adjacent segment degeneration after fusion. PURPOSE To investigate if fatty infiltration of LM is associated with adjacent segment degeneration after L4...

BACKGROUND CONTEXT HU on computed tomography (CT) has been associated with bone mineral density (BMD). We wished to correlate PJK after ASD surgery and HU as measured by CT. PURPOSE To evaluate if HU at the UIV, UIV+1 and UIV+2 was correlated with PJK. STUDY DESIGN/SETTING A retrospective study. PATIENT SAMPLE Single center with ASD patients und...

BACKGROUND CONTEXT Cage subsidence can occur after LLIF, and poor bone quality may contribute. HU measured on CT has been correlated with bone density. PURPOSE We evaluated the correlation between HU and cage subsidence after LLIF. STUDY DESIGN/SETTING Retrospective study. PATIENT SAMPLE Patients undergoing single level LLIF with pedicle screw f...

BACKGROUND CONTEXT There remains a need for practical radiographic parameters to help predict risk of proximal junctional kyphosis (PJK) in adult patients undergoing multilevel posterior fusion. The upper instrumented vertebral pelvic angle (UIVPA) is a novel measure of sagittal alignment that is easy to measure and can account for both spinal incl...

OBJECTIVE One vexing problem after lateral lumbar interbody fusion (LLIF) surgery is cage subsidence. Low bone mineral density (BMD) may contribute to subsidence, and BMD is correlated with Hounsfield units (HUs) on CT. The authors investigated if lower HU values correlated with subsidence after LLIF. METHODS A retrospective study of patients unde...

OBJECTIVE Patients undergoing long-segment fusions from the lower thoracic (LT) spine to the sacrum for adult spinal deformity (ASD) correction are at risk for proximal junctional kyphosis (PJK). One mechanism of PJK is fracture of the upper instrumented vertebra (UIV) or higher (UIV+1), which may be related to bone mineral density (BMD). Because H...

Study design: Retrospective case series. Objectives: Both the rate and complexity of spine surgeries in elderly patients has increased. This study reports the outcomes of multilevel spine fusion in elderly patients and provides evidence on the appropriateness of complex surgery in elderly patients. Methods: We identified 101 patients older tha...

OBJECTIVE Anterior approaches to the lumbar spine provide wide exposure that facilitates placement of large grafts with high fusion rates. There are limited data on the effects of obesity on perioperative complications. METHODS Data from consecutive patients undergoing anterior lumbar interbody fusion (ALIF) from 2007 to 2016 at a single academic...

BACKGROUND CONTEXT Factors that influence length of stay (LOS), readmission, and reoperation after adult spinal deformity (ASD) operations are important to define in order to optimize outcomes and control costs. PURPOSE To identify predictors of LOS and 30-day and 90-day readmissions and reoperations following ASD operations. STUDY DESIGN/SETTING...

BACKGROUND CONTEXT Adjacent-segment disease (ASD) of the cervical spine is a common disabling phenomenon that often requires operative intervention. PURPOSE To evaluate the economic impact of revision operations for cervical ASD after previous cervical spine surgery. STUDY DESIGN/SETTING Single-center retrospective cohort analysis. PATIENT SAMPL...

BACKGROUND CONTEXT As spine types have been classified into 4 Roussouly types based upon their sacral slope and shape, it is unclear if certain types lead to higher or lower rates of adjacent segment breakdown after spinal fusion for scoliosis. PURPOSE There are certain Roussouly types that may predispose patients to a higher rate of proximal segm...

BACKGROUND CONTEXT Lumbar spinal fusion is an increasingly common procedure for treating degenerative diseases of the lumbar spine. Non-solid fusion, or pseudarthrosis, at one year is a common complication associated with poor clinical outcomes and need for revision surgery. The risk of pseudarthrosis depends on the number of levels fused, the fusi...

BACKGROUND CONTEXT Pseudarthrosis is a common indication for revision spine operations. Clinical presentations of pseudarthrosis are heterogeneous. While the majority of patients present with pain, many can be symptomatic. Etiologies of pseudarthrosis also vary from structural to biologic, including infection. PURPOSE To determine prevalence of su...

Study Design Cost analysis of a retrospectively identified cohort of patients who had undergone primary single-level lumbar fusion at a single institution’s orthopedic or neurosurgery department. Objective The purpose of this article is to analyze the determinants of direct costs for single-level lumbar fusions and identify potential areas for cos...

Background: Asymmetric pedicle subtraction osteotomy (APSO) can be utilized for adult spinal deformity (ASD) with fixed coronal plane imbalance. There are few reports investigating outcomes following APSO and no series that include multiple revision cases. Objective: To detail our surgical technique and experience with APSO. Methods: All thora...

As new technologies emerge, the applications of minimally invasive spine surgery continue to expand. The need for minimizing the morbidity of surgical access in debilitated patients has propelled a movement toward the increased use of minimally invasive spine surgery for the treatment of pathologic spine fractures.

Background context: Scoli-RISK-1 is a multicenter prospective cohort designed to study neurologic outcomes following complex adult spinal deformity (ASD). The effect of unilateral versus bilateral postoperative motor deficits on the likelihood of long term recovery has not been previously studied in this population. Purpose: Evaluate if bilatera...

Background context: Significant variability in neurologic outcomes after surgical correction for adult spinal deformity (ASD) has been reported. Risk factors for decline in neurologic motor outcomes are poorly understood. Purpose: The objective of the present investigation was to identify the risk factors for postoperative neurologic motor decli...

Proximal junctional kyphosis (PJK) and adjacent segment degeneration (ASD) are important causes of reoperation for adult spinal deformity (). Reducing junctional complications can improve outcomes and cost-effectiveness of treatment. Rigid fixation is associated with significant proximal junctional pathology, but no clinical evidence indicates that...

Study design: The RAND/UCLA Appropriateness Method is a well-established means of developing criteria for assessing the appropriateness of surgery in specific subpopulations. It involves a systematic review of the literature and ratings by a multidisciplinary panel of national experts. Objective: To evaluate the appropriateness of surgical inter...

Study design: Retrospective study of benchmarking database. Objective: To evaluate the variability in direct costs of spinal implants across various academic medical centers, determining variability between and within specific manufacturers, and to measure the relationship between purchasing volume and price. Summary of background data: Spinal...

Disorders of the spine are common and have a significant and measurable burden on affected patients and on our healthcare economy. The burden of spinal disorders encompasses metrics such as the prevalence of spinal disorders, the impact of spinal disorders on health-related quality of life, and the use of resources associated with the operative and...

Eur Spine J (2015) 24 (Suppl 6):S743–S800

Background The aim of this study was to analyze and compare the surgical data, clinical outcomes, and complications between three-column osteotomy (3-COS) and standard surgical management (SSM) for the treatment of adult spine deformity (ASD).MethodsA total of 112 patients who underwent consecutive 3-COS (n¿=¿48) and SSM (n¿=¿64) procedures for ASD...

Value-based health care is an increasingly important priority in our health care economy and has particular relevance to the field of spine surgery. Value includes a consideration of both quality and cost—the value of a health care intervention is assessed by whether it provides an incremental benefit in outcome to justify an incremental increase i...

The treatment of painful vertebral compression fractures has changed substantially since the introduction of vertebroplasty in the mid-1980s and balloon kyphoplasty in the late 1990s. Both procedures were widely accepted with the vertebral fractures treated reaching 150,000 per annum in 2009 prior to the publication of 2 randomized controlled trial...

We reviewed all peer-reviewed papers analysing the cost-effectiveness of vertebroplasty and balloon kyphoplasty for osteoporotic vertebral compression fractures. In general, the procedures appear to be cost effective but are very dependent upon model input details. Better data, rather than new models, are needed to answer outstanding questions. Ver...

Study design: Systematic review. Objective: To evaluate the cost-effectiveness of lumbar or cervical spinal arthrodesis using biological substitutes and extenders compared with iliac crest autograft for the treatment of degenerative spinal conditions. Summary of background data: The cost-effectiveness of using bone graft substitutes and extend...

Study Design. Narrative overview. Objective. To provide clinicians with a basic understanding of economic studies, including cost-benefit, cost-effectiveness, and cost-utility analyses. Summary of Background Data. As decisions regarding public health policy, insurance reimbursement, and patient care incorporate factors other than traditional outcom...

Axial myopathy can be the underlying cause of rapidly progressive adult-onset scoliosis; however, the pathogenesis of this disorder remains poorly understood. Here we present a case of a 69-year old woman with a family history of scoliosis affecting both her mother and her son, who over 4 years developed rapidly progressive scoliosis. The patient h...

Objectives The sacroiliac joint (SIJ) is an important and significant cause of low back pain. We sought to quantify the burden of disease attributable to the SIJ. Methods The authors compared EuroQol 5D (EQ-5D) and Short Form (SF)-36-based health state utility values derived from the preoperative evaluation of patients with chronic SIJ pain partic...

Metastatic bone disease has a significant effect on a patient's mortality and health-related quality of life. An aging US population and improved survival rates of patients with cancer have led to an increase in the incidence of symptomatic bony metastatic lesions that may require orthopaedic care. Skeletal-related events in neoplastic disease incl...

In the U.S., direct expenditures involving health-care costs and indirect expenditures involving lost wages of persons with musculoskeletal diseases have been estimated to total $950 billion, or 7.4% percent of the U.S. gross national product, in 2004-20061. Despite this enormous financial burden, in addition to the personal and societal impact, mu...

Object: The authors present 1-year results in 60 patients with cervical radiculopathy due to spondylosis and stenosis that was treated with a bilateral percutaneous facet implant. The implant consists of a screw and washer that distracts and immobilizes the cervical facet for root decompression and fusion. Clinical and radiological results are ana...

Laminectomy/laminotomy and foraminotomy are well established surgical techniques for treatment of symptomatic lumbar spinal stenosis. However, these procedures have significant limitations, including limited access to lateral and foraminal compression and postoperative instability. The purpose of this cadaver study was to compare bone, ligament, an...