Andrew A Sama

Hospital for Special Surgery · Spine Care Institute

Study design Retrospective study. Objective The aim of this study was to evaluate the association between severity and level of cervical central stenosis (CCS) and the fat infiltration (FI) of the cervical multifidus/rotatores (MR) at each subaxial levels. Summary of Background Data The relationship between cervical musculature morphology and the...

Paraspinal muscle atrophy is gaining attention in spine surgery due to its link to back pain, spinal degeneration and worse postoperative outcomes. Electrical impedance myography (EIM) is a noninvasive diagnostic tool for muscle quality assessment, primarily utilized for patients with neuromuscular diseases. However, EIM's accuracy for paraspinal m...

Lumbar medial branch radiofrequency neurotomy (RFN), a common treatment for chronic low back pain due to facet joint osteoarthritis (FJOA), may amplify paraspinal muscle atrophy due to denervation. This study aimed to investigate the asymmetry of paraspinal muscle morphology change in patients undergoing unilateral lumbar medial branch RFN. Data fr...

Objective Abdominal aortic calcification (AAC), often found incidentally on lateral lumbar radiographs, is increasingly recognized for its association with adverse outcomes in spine surgery. As a marker of advanced atherosclerosis affecting cardiovascular dynamics, this study evaluates AAC’s impact on perioperative blood loss in posterior spinal fu...

We aim to investigate the associations between lumbar paraspinal muscles and sagittal malalignment in patients undergoing lumbar three-column osteotomy. Patients undergoing three-column osteotomy between 2016 and 2021 with preoperative lumbar magnetic resonance imaging (MRI) and whole spine radiographs in the standing position were included. Muscle...

Background The recommended timing for returning to common activities after cervical spine surgery varies widely among physicians based on training background and personal opinion, without clear guidelines or consensus. The purpose of this study was to analyze spine surgeons’ responses about the recommended timing for returning to common activities...

Study Design Retrospective longitudinal study. Objective To investigate the association between lumbar intervertebral disc degeneration (DD) and the vertebral bone quality (VBQ) score. Summary of Background Data The VBQ score that is based on magnetic resonance imaging (MRI) has been proposed as a measure of lumbar spine bone quality and is a sig...

Purpose Intervertebral vacuum phenomenon (IVP) and paraspinal muscular atrophy are age-related changes in the lumbar spine. The relationship between both parameters has not been investigated. We aimed to analyze the correlation between IVP and paraspinal muscular atrophy in addition to describing the lumbar vacuum severity (LVS) scale, a new parame...

Background The modified frailty index (mFI-5) has been shown to be a reliable risk stratification tool in different spine procedures. Its usefulness to predict complications after 1-level or 2-level anterior cervical decompression and fusion (ACDF) has not been studied extensively. Purpose We aimed to assess the usefulness of the mFI-5 in 1-level...

Cervical myelopathy, a condition caused by compression of the spinal cord in the neck, is characterized by an insidious onset with slow clinical deterioration; however, it can have a rapid progression in a subset of patients, culminating in spinal cord damage/injury. In elderly patients, Cervical myelopathy is marked by multifaceted deterioration o...

Study Design Retrospective review of prospectively collected data. Objective We aim to investigate the association between muscle functional group characteristics and sagittal alignment parameters in patients undergoing anterior cervical discectomy and fusion (ACDF). Summary of Background Data The relationship between the cervical paraspinal musc...

OBJECTIVE The cervical multifidus and rotatores muscles are innervated by the posterior rami of the spinal nerves of the corresponding level, and it has been hypothesized that cervical foraminal stenosis (CFS) affecting the spinal nerves results in changes in these muscles. The purpose of this study was to evaluate the relationship between the seve...

Background The function of the paraspinal muscles and especially the psoas muscle in maintaining an upright posture is not fully understood. While usually considered solely as a hip flexor, the psoas muscle and its complex anatomy suggest that the muscle has other functions involved in stabilizing the lumbar spine. The aim of this study is to deter...

Abdominal aortic calcification (AAC) is hypothesized to lead to ischemic pain of the lower back. This retrospective study aims to identify the relationship between AAC and lower back pain (LBP) in patients with degenerative lumbar spondylolisthesis. Lower back pain was assessed preoperatively and 2 years after surgery using the numeric analogue sca...

Purpose The goals were to ascertain if differences in imaging/clinical characteristics between women and men were associated with differences in fusion for lumbar degenerative spondylolisthesis. Methods Patients had preoperative standing radiographs, CT scans, and intraoperative fluoroscopic images. Symptoms and comorbidity were obtained from pati...

Study Design Retrospective analysis of prospectively enrolled patients. Objective To evaluate the relationship between paraspinal muscle (PM) atrophy and Oswestry Disability Index (ODI) improvement after spinal fusion surgery for degenerative lumbar spondylolisthesis (DLS). Background Atrophy of the PM is linked to multiple spinal conditions, sag...

Study Design A retrospective analysis of prospectively collected data Objective To assess the association between intervertebral disc degeneration and hip and knee osteoarthritis (OA) in patients with degenerative lumbar spondylolisthesis (DLS). Background The co-occurrence of hip OA and degenerative spinal pathologies was first described as the...

Background Context Although the effect of lumbar spinal stenosis (LSS) on the lower extremities is well documented, limited research exists on the effect of spinal stenosis on the posterior paraspinal musculature (PPM). Similar to neurogenic claudication, moderate to severe spinal canal compression can also interfere with the innervation of the PPM...

Introduction Degenerative lumbar spondylolisthesis (DLS) is a prevalent spinal disorder, often requiring surgical intervention. Accurately predicting surgical outcomes is crucial to guide clinical decision-making, but this is challenging due to the multifactorial nature of postoperative results. Traditional risk assessment tools have limitations, a...

Lateral lumbar interbody fusion (LLIF) is a minimally invasive surgical approach used to treat a variety of degenerative and deformity conditions of the lumbar spine such as advanced degenerative disease, degenerative scoliosis, foraminal and central stenosis. It has emerged as an alternative to the traditional posterior and anterior lumbar approac...

BACKGROUND CONTEXT In an era of rising health care costs and pressure to improve patient satisfaction, surgeries are increasingly performed in an ambulatory setting. One example is anterior cervical discectomy and fusion (ACDF), which is one of the most common cervical spine surgeries. However, there are certain patients who are unexpectedly conver...

BACKGROUND CONTEXT The association between cervical paraspinal muscles and cervical sagittal balance is important when considering the multifactorial causes of cervical spinal degeneration. The associations between each of the cervical paraspinal muscle groups and sagittal alignment are not well understood. Given the key functional differences betw...

BACKGROUND CONTEXT Low back pain (LBP) is a common and often debilitating condition that negatively impacts patient quality of life. Multiple studies suggest that abdominal aortic calcification (AAC) is linked to spinal pathologies, such as disc degeneration as well as reduced bone mineral density that can contribute to the development of LBP. Simi...

Introduction The vertebral bone quality (VBQ) score that is based on non-contrast enhanced T1-weighted MRI was recently introduced as a novel measure of bone quality in the lumbar spine and shown to be a significant predictor of healthy versus osteopenic/osteoporotic bone. Research question This study aimed to assess possible correlations between...

Study design: Retrospective study of prospective collected data. Objective: To analyze the association between intervertebral vacuum phenomenon (IVP) and clinical parameters in patients with degenerative spondylolisthesis. Summary of background data: IVP is a sign of advanced disc degeneration. The correlation between IVP severity and low back...

Background Abdominal aortic calcification (AAC) is associated with lower back pain, reduced bone mineral density of the spine. Vascular changes could also affect the already sparsely perfused intervertebral endplate and intervertebral disc. Methods Lumbar MRIs and lateral radiographs of patients with lower back pain were retrospectively analyzed....

Purpose: The primary objective of this study is to determine if ultrasound-guided erector spinae plane blocks (ESPB) prior to thoracolumbar spinal fusion reduces opioid consumption in the first 24 hours postoperatively. Secondary objectives include ESPB effects on administration of opioids, utilization of intravenous patient-controlled analgesia (...

Purpose The aim of this study was to determine whether the presence of abdominal aortic calcification (AAC) can predict patient bone status, represented by volumetric bone mineral density (vBMD) assessed with quantitative computed tomography (QCT). Methods Patients undergoing lumbar fusion surgery at a tertiary care center between 2014 and 2021, w...

Study design/setting: A retrospective observational study. Objective: To investigate the factors associated with the conversion of patient status from ambulatory anterior cervical discectomy and fusion (ACDF) to inpatient. Summary of background data: Surgeries are increasingly performed in an ambulatory setting in an era of rising healthcare c...

Purpose This study aimed to investigate the changes of the posterior paraspinal muscles (PPM) and psoas muscle in patients with low back pain (LBP) over time. Methods Patients with LBP who had a repeat lumbar MRI with a minimum of 3-years apart at a tertiary referral center were analyzed. MRI-based quantitative assessments of the PPM and the psoas...

Study design: A retrospective analysis of prospectively collected data. Objective: To report the decision-making process for DA and DF at a tertiary orthopedic center and compare the operative outcomes between both groups. Background: Controversy exists around the optimal operative treatment for DLS, either with decompression and fusion (DF) or d...

Background Aortic abdominal calcification (AAC) is associated with spine-related conditions, such as lower back pain and reduced bone mineral density. Similar to peripheral vascular disease, AAC possibly reduces blood flow to the lumbar posterior paraspinal muscles (PPM) which may lead to atrophy and increased fatty infiltration. Methods Imaging o...

Background Frailty status has been associated with higher rates of complications after spine surgery. However, frailty patients constitute an heterogeneous group based on the combinations of comorbidities. The objective of this study is to compare the combinations of variables that compose the modified 5-factor frailty index score (mFI-5) based on...

Background Erector spinae plane blocks are used to improve outcomes after spine surgery, but pain frequently outlasts the duration of single injection blocks. We hypothesized continuous erector spinae plane (cESP) catheters would provide superior analgesia. We terminated a prospective double-blinded randomized clinical trial (RCT) comparing outcome...

Purpose There are reports that performing lateral lumbar interbody fusion (LLIF) in a prone, single position (single-prone LLIF) can be done safely in the prone position because the retroperitoneal organs reflect anteriorly with gravity. However, only a few study has investigated the safety of single-prone LLIF and retroperitoneal organ positioning...

Purpose Sagittal spinal malalignment often leads to surgical realignment, which is associated with major complications. Low bone mineral density (BMD) and impaired bone microstructure are risk factors for instrumentation failure. This study aims to demonstrate differences in volumetric BMD and bone microstructure between normal and pathological sag...

Objective: Cervical disc replacement (CDR) is an alternative treatment to anterior cervical discectomy and fusion (ACDF), which is the current gold standard, for degenerative cervical diseases such as cervical spondylotic myelopathy and cervical radiculopathy. CDR has several theoretical benefits over ACDF, including preservation of motion, earlie...

Study design: Retrospective database analysis. Objective: To elucidate trends in the utilization of IONM during elective lumbar surgery procedures and to investigate the association between the use of IONM and surgical outcomes. Summary of background data: The routine use of Intraoperative Neurophysiological Monitoring (IONM) in elective lumba...

Study design: Prospective cross-sectional study. Objective: To determine if an accumulation of advanced glycation endproducts (AGEs) is associated with impaired paraspinal muscle composition. Summary of background data: Impaired bone integrity and muscle function are described as osteosarcopenia. Osteosarcopenia is associated with falls, fragi...

Purpose: The sole determination of volumetric bone mineral density (vBMD) is insufficient to evaluate overall bone integrity. The accumulation of advanced glycation endproducts (AGEs) stiffens and embrittles collagen fibers. Despite the important role of AGEs in bone aging, the relationship between AGEs and vBMD is poorly understood. We hypothesiz...

Study design: A retrospective observational study. Objective: To investigate the factors associated with the conversion of patient status from Ambulatory surgery (AMS) to observation service (OS) (fewer than 48 hours) or Inpatient (greater than 48 hours). Summary of background data: AMS is becoming increasingly common in the U.S. because it is...

Purpose: Standalone lateral lumbar interbody fusion (SA-LLIF) without posterior instrumentation can be an alternative to 360° fusion in selected cases. This study aimed to investigate quantitative changes in psoas and paraspinal muscle morphology that occur on index levels after SA-LLIF. Methods: Patients undergoing single- or multi-level SA-LLI...

Purpose The vertebral bone quality (VBQ) score based on magnetic resonance imaging (MRI) was introduced as a bone quality marker in the lumbar spine. Prior studies showed that it could be utilized as a predictor of osteoporotic fracture or complications after instrumented spine surgery. The objective of this study was to evaluate the correlation be...

Abstract Background Low back pain (LBP) is a common cause of disability worldwide, multiple causes and risk factors have been proposed in the genesis of back pain. Some studies reported an association between diastasis recti abdominis (DRA), a surrogate for decreased core strength muscle, and low back pain. We aimed to investigate the relationship...

Abstract Background Frailty status and hypoalbuminemia have been associated with higher rates of complications after spine surgery. However, the combination of both conditions has not been fully analyzed. The objective of this study was to assess the effect of frailty and hypoalbuminemia on the risk of complications after spine surgery. Methods Th...

Purpose To investigate the influence of vertebral endplate defects and subchondral bone marrow changes on the development of lumbar intervertebral disc degeneration (DD). Methods Patients > 18 y/o without any history of lumbar fusion who had repeat lumbar magnetic resonance imaging scans primarily for low back pain (LBP) performed at a minimum of...

Background The impact of anesthetic technique on spine surgery outcomes is controversial. Using a large national sample of patients, we compared outcomes after lumbar decompression under regional anesthesia (RA: spinal or epidural) or general anesthesia (GA). Methods A retrospective population-based study of American College of Surgeons National S...

Background context: Fulfillment of expectations is a patient-centered outcome that has not been assessed based on fusion status for lumbar degenerative spondylolisthesis (LDS). Purpose: To compare preoperatively cited expectations and 2-year postoperative fulfillment of expectations between patients undergoing decompression alone (no-fusion) ver...

Background: Assessing the impact of spine disorders such as lumbar degenerative spondylolisthesis (LDS) on overall health is a component of quality of care that may not be comprehensively captured by spine-specific and single-attribute patient-reported outcome measures (PROMs). Purpose: We sought to compare PROMs to the Lumbar Surgery Expectations...

Study design: Retrospective cohort analysis. Objective: To elucidate trends in the utilization of intraoperative neuromonitoring (IONM) during elective anterior cervical decompression and fusion (ACDF) procedures in New York State using the Statewide Planning and Research Cooperative System (SPARCS) and to determine if utilization of IONM result...

Purpose: Lumbar fusion surgery has become a standard procedure in spine surgery and commonly includes the posterior placement of pedicle screws. Bone quality is a crucial factor that affects pedicle screw purchase. However, the relationship between paraspinal muscles and the bone quality of the pedicle is unknown. The aim of the study was to deter...

PurposeWe sought to characterize trends in demographics, comorbidities, and postoperative complications among patients undergoing primary and revision cervical disc replacement (pCDR/rCDR) procedures. Methods In this retrospective database study, the Premier Healthcare database was queried from 2006 to 2019. Annual proportions or medians were calcu...

Study design: Retrospective cross-sectional study. Objective: To assess the association between spinal muscle morphology and spinopelvic parameters in lumbar fusion patients, with a special emphasis on lumbar lordosis (LL). Summary of background data: Maintenance of sagittal alignment relies on muscle forces, but the basic association between...

Study design: Cross-sectional preoperative and intraoperative imaging study of L4-5 lumbar degenerative spondylolisthesis (LDS). Objective: To determine if alternate imaging modalities would identify LDS instability that did not meet criteria for instability based on comparison of flexion and extension radiographs. Summary of background data:...

Background: Compare fusion at two independent timepoints (early and late) between 3D-printed titanium (Ti) and polyetheretherketone (PEEK) cages in patients undergoing standalone lateral lumbar interbody fusion (SA-LLIF). We hypothesized that 3D-printed Ti cages show higher fusion rates at an early timepoint compared to PEEK. Methods: A retrospe...

BACKGROUND CONTEXT Bone quality, apart from bone mineral density, is increasingly recognized for its importance in the assessment of fracture risk. Collagen cross-linking is a relevant factor for determining the tensile strength of bone. Non-enzymatic collagen cross-linking with the accumulation of advanced glycation end products (AGEs) stiffens an...

BACKGROUND CONTEXT Lumbar fusion surgery has become a standard procedure in spine surgery and commonly includes posterior placement of pedicle screws. Bone quality is a critical factor that affects pedicle screw purchase, whereas the role of paraspinal musculature is less well understood. Pedicle screw loosening is a devastating complication often...

BACKGROUND CONTEXT Pathophysiological conditions during aging can affect bone and muscle simultaneously, such as in osteosarcopenia. The vertebral bone quality (VBQ) score based on magnetic resonance imaging (MRI) was recently introduced as a novel measure of bone quality in the lumbar spine and shown to be a significant predictor of healthy versus...

BACKGROUND CONTEXT Opioid analgesics are commonly utilized to manage postoperative pain following spinal surgery. This class of medications is associated with a variety of side effects that often contribute to additional morbidity and prolonged hospitalization. In an effort to reduce opioid consumption, alternatives such as intravenous acetaminophe...

BACKGROUND CONTEXT Ambulatory surgery (AMS), or outpatient surgery, is increasingly common for patients with lumbar spine disease. Previous reports suggest AMS is associated with lower cost and similar quality of care compared to conventional inpatient spine surgery. Under the current Center for Medicare and Medicaid services (CMS) two-midnight rul...

BACKGROUND CONTEXT Loss of paraspinal muscle mass over time can affect spinal degeneration and promote lumbar back pain. New methods to determine muscle quantity and quality have been established, including the evaluation of the functional cross-sectional area (fCSA) and fat infiltration. However, little is known about the aging processes that occu...

BACKGROUND CONTEXT Quantitative computed tomography (QCT) is considered a standard reportable metric for the measurement of bone mineral density (BMD) of the lumbar spine. However, the sole determination of BMD is insufficient for the evaluation of overall bone health. Consequently, bone quality, apart from BMD, is increasingly recognized for its i...

BACKGROUND CONTEXT Occult bacteria have been linked to deep and chronic infections in spine surgery. These organisms are commensal to dermal and deeper tissue layers, including the intervertebral disc and bone. We hypothesize that standard surgical skin preparation nor preoperative antibiotics properly access and eradicate these organisms prior to...

Purpose To investigate whether (1) there is a difference between patients with normal or sagittal spinal and spinopelvic malalignment in terms of their paraspinal muscle composition and (2) if sagittal malalignment can be predicted using muscle parameters. Methods A retrospective review of patients undergoing posterior lumbar fusion surgery was co...

Purpose The aim of this study was to determine the effect of age on the psoas and posterior paraspinal muscles (PPM; multifidus muscle and erector spinae) and to evaluate potential sex-related differences. Methods MRI-based quantitative assessments of the cross-sectional area (CSA), the functional cross-sectional area (fCSA), the fat area (FAT) an...

Background: Advanced glycation end products (AGEs) have been shown to accumulate in bone and are gaining interest in connective tissue research. Aims: To investigate the intrarater reliability, two-timepoint agreement and correlations within and between two commercially available skin autofluorescence (SAF) AGE devices. Methods: Healthy volunt...

Osteosarcopenia is a common condition among elderly and postmenopausal female patients. Site-specific bone mineral density is more predictive of bone-related complications. Few studies have investigated muscle-bone associations. Our results demonstrated that in women, significant positive associations between paraspinal muscles FCSA and vBMD exist...

Background Context The concept of sagittal spinal malalignment is well established in spinal surgery. However, the effect of musculature on its development has not been fully considered and the position of the pelvis is mostly seen as compensatory and not necessarily a possible cause of sagittal imbalance. Purpose This study aimed to investigate t...

Background: Postoperative pain management of multilevel lumbar fusion remains challenging. There are few reports of opioid-sparing regional analgesia for spine surgery. We present a novel method for surgeon-placed erector spinae plane (ESP) catheters for multilevel lumbar spine fusion and compare pain- and opioid-related outcomes in a matched coho...

Purpose To develop a decision-making pathway for primary SA-LLIF. Furthermore, we analyzed the agreement of this pathway and compared outcomes of patients undergoing either SA-LLIF or 360-LLIF. Method A decision-making pathway for SA-LLIF was created based on the results of interviews/surveys of senior spine surgeons with over 10 years of experien...

Background Context Studies have shown site-specific bone density measurements had more predictive value for complications than standard whole-region measurements. Recently, MRI-based assessments of the vertebral bone quality (VBQ) were introduced. However, there have been few studies that investigate the association between site-specific MRI bone a...

Background: Quantitative computed tomography (qCT) efficiently measures 3-dimensional vertebral bone mineral density (BMD), but its utility in measuring BMD at various vertebral levels in patients with lumbar degenerative spondylolisthesis (LDS) is unclear. Purpose: We sought to determine whether qCT could differentiate BMD at different levels of L...

Background Context Osteoporosis is a risk factor for instrumentation failure in spine surgery. Bone strength is commonly assessed by bone mineral density (BMD) as a surrogate marker. However, BMD represents only a portion of bone strength and does not capture the qualitative dimensions of bone. Recently, the magnetic resonance imaging (MRI)-based v...

Bone quality is increasingly being recognized in the assessment of fracture risk. Non‐enzymatic collagen cross‐linking with the accumulation of advanced glycation end products stiffens and embrittles collagen fibers thus increasing bone fragility. Echogenicity is an ultrasound(US) parameter that provides information regarding the skin collagen stru...

Study design Retrospective observational population-based study Objectives Aims of this study were to determine the time trend of demographics, complications, and outcomes for patients undergoing posterior/transforaminal (PLIF/TLIF) or anterior/lateral lumbar interbody fusion (ALIF/LLIF) and to compare the differences in the time trends between bo...

Purpose: Presumed benefits of erector spinae plane blocks (ESPB) include an enhanced safety profile and few complications. There are few large series, which report the incidence of complications associated with ESPB on a procedure-specific basis. The objective of this retrospective cohort study was to estimate the incidence of complications of ESP...

Background context: The importance of bone status assessment in spine surgery is well recognized. The current gold standard for assessing bone mineral density is dual-energy X-ray absorptiometry (DEXA). However, DEXA has been shown to overestimate BMD in patients with spinal degenerative disease and obesity. Consequently, alternative radiographic m...

BACKGROUND CONTEXT: The effect of psoas and paraspinal muscle parameters on cage subsidence after minimally invasive techniques, such as standalone lateral lumbar interbody fusion (SA-LLIF), is unknown. PURPOSE: This study aimed to determine whether the functional cross-sectional area (FCSA) of psoas and lumbar spine extensor muscles (multifidus an...

Venous thromboembolism (VTE) and pulmonary embolism (PE) represent a significant portion of morbidity and mortality across all facets of spine surgery. Extensive research has developed preoperative risk profiles to identify high risk patients. Modern practices including early mobilization, mechanical, and chemoprophylaxis have substantially reduced...

This study aimed at quantifying trabecular volumetric bone mineral density (vBMD) at the external occipital protuberance (EOP) and the upper cervical spine. A retrospective review of patients who underwent non-contrast enhanced computed tomography of the cervical spine that included the occipital bone up to the EOP between 2007 and 2020 was conduct...