Grace Xiong, MD

All Publications

• Guidelines for returning to activity after spinal deformity surgery. Spine deformity Turtle, J. D., Mehta, J. S., Parent, S., Xiong, G. X., Cheung, J. P., Welborn, M. C., Vaccaro, A. R., Cahill, P. J., Pellisé, F., Hu, S. S. 2024

  Abstract

  Returning to activity after spinal deformity surgery is vital for patient recovery and long-term health, yet there is significant variability in postoperative protocols among surgeons worldwide. This paper aims to define guidelines for returning to activity across diverse patient groups: early onset scoliosis (EOS), adolescent idiopathic scoliosis (AIS), young adults, adult spinal deformity (ASD), elite athletes, and general sports participants. This paper provides guidelines to foster a unified approach to postoperative care, improving outcomes and ensuring patients can safely and effectively resume their activities. This paper represents the proceedings of an SRS educational CME webinar. A summary of recommendations for each patient group is included aiming to enhance surgeon practice and patient care through standardized postoperative protocols.

  View details for DOI 10.1007/s43390-024-01010-x

  View details for PubMedID 39616557

  View details for PubMedCentralID 4922518

• What Happens to Sagittal Alignment Following Laminoplasty Versus Laminectomy and Fusion? WORLD NEUROSURGERY Lindsey, M. H., Lightsey, H. M., Xiong, G. X., Goh, B., Simpson, A. K., Hershman, S. H. 2024; 184: E211-E218

  Abstract

  Laminectomy and fusion (LF) and laminoplasty (LP) are 2 sucessful posterior decompression techniques for cervical myelo-radiculopathy. There is also a growing body of evidence describing the importance of cervical sagittal alignment (CSA) and its importance in outcomes. We investigated the difference between pre- and postoperative CSA parameters in and between LF or LP. Furthermore, we studied predictive variables associated with change in cervical mismatch (CM).This is a retrospective cohort study of adults with cervical myeloradiculopathy in a single healthcare system. The primary outcomes are intra- and inter-cohort comparison of LF versus LP radiographic parameters at pre- and postoperative time points. A secondary multivariable analysis of predictive factors was performed evaluating factors predicting postoperative CM.Eighty nine patients were included; 38 (43%) had LF and 51 (57%) underwent LP. Both groups decreased in lordosis (LF 11.4° vs. 4.9°, P = 0.01; LP 15.2° vs. 9.1°, P < 0.001), increased in cSVA (LF 3.4 vs. 4.2 cm, P = 0.01; LP 3.2 vs. 4.2 cm, P < 0.001), and increased in CM (LF 22.0° vs. 28.5°, P = 0.02; LP 16.8° vs. 22.3°, P = 0.002). There were no significant differences in the postoperative CSA between groups. No significant predictors of change in pre- and postoperative CM were found.There were no significant pre-or postoperative differences following the 2 procedures, suggesting radiographic equipoise in well indicated patients. Across all groups, lordosis decreased, cSVA increased, and cervical mismatch increased. There were no predictive factors that led to change in cervical mismatch.

  View details for DOI 10.1016/j.wneu.2024.01.087

  View details for Web of Science ID 001226702200001

  View details for PubMedID 38266988

• Use of vancomycin and gentamicin-impregnated calcium sulfate beads for the prevention of surgical site infection in adult spinal deformity SPINE JOURNAL Xiong, G. X., Hammoor, B. T., Simpson, A. K., Hershman, S. H. 2024; 24 (2): 330-332

  View details for DOI 10.1016/j.spinee.2023.10.002

  View details for Web of Science ID 001171349600001

  View details for PubMedID 37890726

• Projected lifetime cancer risk for patients undergoing spine surgery for isthmic spondylolisthesis SPINE JOURNAL Crawford, A. M., Striano, B. M., Lightsey, H. M., Zhu, J. S., Xiong, G. X., Schoenfeld, A. J., Simpson, A. K. 2023; 23 (6): 824-831

  Abstract

  Radiographs, fluoroscopy, and computed tomography (CT) are increasingly utilized in the diagnosis and management of various spine pathologies. Such modalities utilize ionizing radiation, a known cause of carcinogenesis. While the radiation doses such studies confer has been investigated previously, it is less clear how such doses translate to projected cancer risks, which may be a more interpretable metric.(1) Calculate the lifetime cancer risk and the relative contributions of preference-sensitive selection of imaging modalities associated with the surgical management of a common spine pathology, isthmic spondylolisthesis (IS); (2) Investigate whether the use of intraoperative CT, which is being more pervasively adopted, increases the risk of cancer.Retrospective cross-sectional study carried out within a large integrated health care network.Adult patients who underwent surgical treatment of IS via lumbar fusion from January 2016 through December 2021.(1) Effective radiation dose and lifetime cancer risk associated with each exposure to ionizing radiation; (2) Difference in effective radiation dose (and lifetime cancer risk) among patients who received intraoperative CT compared to other intraoperative imaging techniques.Baseline demographics and differences in surgical techniques were characterized. Radiation exposure data were collected from the 2-year period centered on the operative date. Projected risk of cancer from this radiation was calculated utilizing each patient's effective radiation dose in combination with age and sex. Generalized linear modeling was used to adjust for covariates when determining the comparative risk of intraoperative CT as compared to alternative imaging modalities.We included 151 patients in this cohort. The range in calculated cancer risk exclusively from IS management was 1.3-13 cases of cancer per 1,000 patients. During the intraoperative period, CT imaging was found to significantly increase radiation exposure as compared to alternate imaging modalities (adjusted risk difference (ARD) 12.33mSv; IQR 10.04, 14.63mSv; p<.001). For a standardized 40 to 49-year-old female, this projects to an additional 0.72 cases of cancer per 1,000. For the entire 2-year perioperative care episode, intraoperative CT as compared to other intraoperative imaging techniques was not found to increase total ionizing radiation exposure (ARD 9.49mSv; IQR -0.83, 19.81mSv; p=.072). The effect of intraoperative imaging choice was mitigated in part due to preoperative (ARD 13.1mSv, p<.001) and postoperative CTs (ARD 22.7mSv, p<.001).Preference-sensitive imaging decisions in the treatment of IS impart substantial cancer risk. Important drivers of radiation exposure exist in each phase of care, including intraoperative CT and/or CT scans during the perioperative period. Knowledge of these data warrant re-evaluation of current imaging protocols and suggest a need for the development of radiation-sensitive approaches to perioperative imaging.

  View details for DOI 10.1016/j.spinee.2023.01.014

  View details for Web of Science ID 001001430500001

  View details for PubMedID 36736738

• Report of the "Women in Academic Spine" Initiative SPINE Koshinski, J. L., Xiong, G. X., Agaronnik, N., Byrd, C., Call, C. M., Enchill, Z., Giberson-Chen, C., Hering, K., Hislop, C., McGovern, M. M., Parker, A., Schoenfeld, A. L., Yuen, L. C., Ihejirika-Lomedico, R., Lipa, S. A. 2023; 48 (8): 515-518

  View details for DOI 10.1097/BRS.0000000000004608

  View details for Web of Science ID 000960585800003

  View details for PubMedID 36799734

• The impact of radiotherapy on survival after surgical resection of chordoma with minimum five-year follow-up SPINE JOURNAL Tobert, D. G., Kelly, S. P., Xiong, G. X., Chen, Y., MacDonald, S. M., Bongers, M. E., -Calderon, S., Newman, E. T., Raskin, K. A., Schwab, J. H. 2023; 23 (1): 34-41

  Abstract

  Local control remains a vexing problem in the management of chordoma despite advances in operative techniques and radiotherapy (RT) protocols. Existing studies show satisfactory local control rates with different treatment modalities. However, those studies with minimum follow-up more than 4 years demonstrate increasing rates of local failure. Therefore, mid-term local survival rates may be inadvertently elevated by studies with less than 4 years follow-up.The purpose of this study is to report the mid-term results of primary spinal chordoma treated with en bloc resection and proton-based RT with minimum 5 years of follow-up.Retrospective, single-center, cohort study.Patients undergoing primary surgical excision of a spine or sacral chordoma tumor between 1990 and 2016 at a single-institution were included. Patients were included if they had a local failure at any time, or they had a minimum of 5 years of follow up with no local failure. Patients were excluded if a prior surgical excision was performed or metastases were present at the time of referral.The outcome measures were local recurrence-free interval (LRFI) and overall survival (OS).Demographic, clinical, oncologic and surgical variables, including margin status, as well as radiation doses and schedule (neoadjuvant, adjuvant, or both) were compared using Wilcoxon rank-sum or chi-squared testing. The goal RT dose was 70 Gray (total) and patients were stratified based on completing (C70) or receiving incomplete (I70) dosing. Overall survival (OS) and local-recurrence free interval (LRFI) were calculated using the Kaplan-Meier method.No funding was obtained for this work.Seventy-six patients were included in the final analysis. All patients had a minimum of 5-year follow-up (median 9.3 years, range 5.1-24.7 years). There were no significant clinical differences between the C70 and I70 RT groups. OS was greater for the C70 RT group (5-year OS 82% vs. 63%, p=.001). There was similar OS for the positive margin group (5-year OS 70% vs. 61%, p=.266). LRFI was greater for the C70 RT group (5-year OS 93% vs. 78%, p=.017). There was similar LRFI for the positive margin group (5-year OS 90% versus 87%, p=.810).Chordoma outcomes trend towards diminishing LRFI rates in the literature. Here we report the results of the operative management of primary spinal chordoma with minimum five year follow-up, the addition of C70 RT to surgical excision conferred a benefit to OS and local recurrence.

  View details for DOI 10.1016/j.spinee.2022.04.009

  View details for Web of Science ID 001015559700001

  View details for PubMedID 35470086

• Prospective comparison of one-year survival in patients treated operatively and nonoperatively for spinal metastatic disease: results of the prospective observational study of spinal metastasis treatment (POST) SPINE JOURNAL Xiong, G. X., Collins, J. E., Ferrone, M. L., Schoenfeld, A. J. 2023; 23 (1): 14-17

  View details for DOI 10.1016/j.spinee.2022.02.004

  View details for Web of Science ID 000993632500001

  View details for PubMedID 35181541

  View details for PubMedCentralID PMC9378762

• C-reactive Protein-to-albumin Ratio in Spinal Epidural Abscess: Association with Post-treatment Complications JOURNAL OF THE AMERICAN ACADEMY OF ORTHOPAEDIC SURGEONS Lindsey, M. H., Xiong, G. X., Lightsey, H. M., Giberson-Chen, C., Goh, B., Xu, R., Simpson, A. K., Schoenfeld, A. J. 2022; 30 (17): 851-857

  Abstract

  Spinal epidural abscess (SEA) is a complex medical condition with high morbidity and healthcare costs. Clinical presentation and laboratory data may have prognostic value in forecasting morbidity and mortality. C-reactive protein-to-albumin ratio (CAR) demonstrates promise for the prediction of adverse events in multiple orthopaedic and nonorthopaedic surgical conditions. We investigated the relationship between CAR and outcomes after treatment of SEA.We retrospectively evaluated adult patients treated within a single healthcare system for a diagnosis of SEA (2005 to 2017). Laboratory and clinical data included age at diagnosis, sex, race, body mass index, smoking status, history of intravenous drug use, Charlson Comorbidity Index, and CAR. The primary outcome was the occurrence of any complication; mortality and readmissions were considered secondarily. We used logistic regression to determine the association between baseline CAR and outcomes, adjusting for confounders.We included 362 patients with a 90-day mortality rate of 13.3% and a 90-day complication rate of 47.8%. A reduced complication rate was observed in the lowest decile of CAR values compared with the remaining 90% of patients, a threshold value of 2.5 (27.0% versus 50.2%; odds ratio [OR] 2.66, 95% confidence interval [CI] 1.22 to 5.81). CAR values in the highest two deciles experienced significantly increased odds of complications compared with the lowest decile (80th: OR 3.44; 95% CI 1.25 to 9.42; 90th: OR 3.28; 95% CI 1.19 to 9.04).We found elevated CAR to be associated with an increased likelihood of major morbidity in SEA. We suggest using a CAR value of 2.5 as a threshold for enhanced surveillance and recognizing patients with values above 73.7 as being at exceptional risk of morbidity.Level III observational cohort study.

  View details for DOI 10.5435/JAAOS-D-22-00172

  View details for Web of Science ID 000841920800005

  View details for PubMedID 35984080

• Insurance types are correlated with baseline patient-reported outcome measures in patients with adult spinal deformity JOURNAL OF CLINICAL NEUROSCIENCE Amakiri, I. C., Xiong, G. X., Verhofste, B., Crawford, A. M., Schoenfeld, A. J., Simpson, A. K. 2022; 103: 180-187

  Abstract

  Patient-reported outcome measures (PROMs) are increasingly recognized as a key component of healthcare value, allowing comparison of therapeutic impact across different specialties. Prior literature suggests that insurance type may be associated with differing baseline PROMs among patients with degenerative conditions, including lumbar stenosis and hip arthritis. This association, however, has not been investigated for adult spinal deformity (ASD).Baseline PROMs were reviewed from 207 patients with ASD presenting for treatment between 2015 and 2019. The Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function Short Form 10a (PF10a), PROMIS Global-Mental, PROMIS Global-Physical, and visual analogue scale (VAS) for back and leg pain were assessed. Negative binomial regression was used to determine the impact of sociodemographic factors, including insurance type, on severity of symptoms and degree of disability at baseline.Mean age of the study population was 62.2 +/- 15 years, with 61.8 % male prevalence. The Medicaid population had a greater proportion of Hispanic and non-English speaking patients, compared to commercially insured patients. Medicaid insured patients had significantly greater VAS low back pain scores compared with commercially insured individuals (IRR 1.535, 95 % CI 1.122-2.101, p = 0.007).Medicaid insured patients demonstrated worse baseline PROMs at presentation with ASD, as compared to commercially insured or Medicare patients. Stakeholders across spine care delivery should elucidate the etiology of baseline disparities in ASD patients, as they may result from health system asymmetries. In an ecosystem moving toward value-driven treatment algorithms, accounting for and addressing these differences will be necessary to provide equitable care for ASD populations.

  View details for DOI 10.1016/j.jocn.2022.07.015

  View details for Web of Science ID 000888204600016

  View details for PubMedID 35908366

• Impact of insurance type on patient-reported outcome measures in patients with lumbar disc herniation SPINE JOURNAL Xiong, G. X., Goh, B. C., Agaronnik, N., Crawford, A. M., Smith, J. T., Hershman, S. H., Schoenfeld, A. J., Simpson, A. K. 2022; 22 (8): 1309-1317

  Abstract

  Lumbar disc herniations (LDH) are among the most common spinal conditions. Despite increased appreciation for the importance of social determinants of health, the role that these factors play in patients with lumbar disc herniations is poorly defined.To elucidate the association between insurance status and baseline patient reported outcome measures (PROMs) in the setting of lumbar disc herniations.Retrospective cohort study PATIENT SAMPLE: Baseline patient-reported outcome measures (PROMS) were reviewed from 924 adult patients presenting for treatment of lumbar disc herniation within our institutional healthcare system (2015-2020).The Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function Short Form 10a (PF10a), PROMIS Global-Mental, PROMIS Global-Physical, and visual analogue scale (VAS) for back and leg pain were assessed.PROMIS scores at presentation were defined at the primary outcome and insurance status as the primary predictor. Differences in clinical and sociodemographic characteristics between our cohorts, stratified by insurance status, were evaluated using Wilcoxon rank-sum or chi-squared testing. We used multivariable negative binomial regression modeling to adjust for potential confounders including age, gender, race, language, ethnicity, comorbidity index, and median geospatial household income.We included 924 patients, with mean age of 58.4 +/- 15.2 years and 52.6% male prevalence. Patients insured through Medicaid were more likely to be Black, Hispanic, and non-English speaking patients compared with the commercially insured. The Charlson Comorbidity index was significantly higher in the Medicare group. Following adjusted analysis, patients with Medicaid insurance had significantly worse PF10a (IRR, 0.90, 95% CI 0.85-0.96), as well as PROMIS Global-Physical score (IRR 0.88, 95% CI 0.82-0.94), and VAS low back pain (IRR 1.20, 95% CI 1.04-1.40) when compared to the commercially insured.We encountered worse physical function, mental, and pain-related patient-reported outcomes for those with Medicaid insurance in a population of patients presenting for evaluation of lumbar disc herniation. These findings, including worse depression, anxiety, and higher axial back pain scores, merit further investigation into potential health system asymmetries, and should be accounted for by treating providers.

  View details for DOI 10.1016/j.spinee.2022.03.011

  View details for Web of Science ID 000847264400009

  View details for PubMedID 35351668

• Microendoscopic Decompression for Lumbar Disc Herniations: An Analysis of Short and Long Term Patient Reported Outcome Measures JOURNAL OF THE AMERICAN ACADEMY OF ORTHOPAEDIC SURGEONS Lightsey, H. M., Lindsey, M. H., Xiong, G. X., Crawford, A. M., Uzosike, A., Ahn, J., Schoenfeld, A. J., Simpson, A. K. 2022; 30 (12): E859-E866

  View details for DOI 10.5435/JAAOS-D-21-01259

  View details for Web of Science ID 000804855100008

• Orthopaedic Innovation and the Balance With Conflicts of Interest OPERATIVE TECHNIQUES IN ORTHOPAEDICS Xiong, G. X., Kang, J. D. 2022; 32 (2)

  View details for DOI 10.1016/j.oto.2022.100962

  View details for Web of Science ID 000864089200006

• ALIF <i>Versus</i> TLIF for L5-S1 Isthmic Spondylolisthesis: ALIF Demonstrates Superior Segmental and Regional Radiographic Outcomes and Clinical Improvements Across More Patient-reported Outcome Measures Domains SPINE Lightsey, H. M., Pisano, A. J., Striano, B. M., Crawford, A. M., Xiong, G. X., Hershman, S., Schoenfeld, A. J., Simpson, A. K. 2022; 47 (11): 808-816

  View details for DOI 10.1097/BRS.0000000000004333

  View details for Web of Science ID 000807697400009

• Insurance Type is Associated with Baseline Patient-Reported Outcome Measures in Patients with Lumbar Stenosis SPINE Crawford, A. M., Xiong, G. X., Lightsey, H. M., Goh, B. C., Smith, J. T., Hershman, S. H., Schoenfeld, A. J., Simpson, A. K. 2022; 47 (10): 737-744

  Abstract

  Retrospective cohort study.To determine if insurance type is associated with differences in baseline patient-reported outcome measures (PROMs) among patients with lumbar spinal stenosis (LSS).PROMs are increasingly used as means to convey value. Prior research suggests that sociodemographic factors, including insurance type may influence these metrics, with patients who are more socioeconomi-cally disadvantaged reporting poorer baseline PROMs. Nonetheless, this association is yet to be evaluated among patients with spinal stenosis.Six-hundred-eight patients with LSS were identified within a major academic health system. Their baseline Patient-Reported Outcomes Measurement Information System for physical function, pain, anxiety and depression, and visual analogue scale for low back and leg pain were analyzed. Wilcoxon rank-sum testing and chi-squared testing were utilized for descriptive nonadjusted comparisons. Negative binomial regression modeling was performed with PROMs considered as dependent variables, insurance type as the primary predictor, and all other factors (e.g., Charlson Comorbidity Index, age, gender, race, ethnicity, language spoken, and median geospatial household income) considered as covariates.The mean age of the cohort was 62.6 ± 14years with a female majority (50.7%). Patients with Medicaid insurance were younger, more likely to be Hispanic, and less likely to be English-speaking than those with commercial insurance or Medicare. Overall, patients with Medicaid insurance were found to have worse baseline PROMs across almost all domains, with the worst performance in Patient-Reported Outcomes Measurement Information System 10 physical global (incidence rate ration 0.88, 95% confidence interval 0.82-0.95) and mental function (incidence rate ration 0.85, 95% confidence interval 0.80-0.92).LSS patients insured through Medicaid have systematically worse baseline PROMs across almost all domains as compared to those with commercial insurance and Medicare, even after adjusting for confounders. These findings have broad ranging implications for research and healthcare policy, especially when using PROMs as measures of value.

  View details for DOI 10.1097/BRS.0000000000004326

  View details for Web of Science ID 000794859500010

  View details for PubMedID 35102118

• The role of gender in academic productivity, impact, and leadership among academic spine surgeons SPINE JOURNAL Agaronnik, N., Xiong, G. X., Uzosike, A., Crawford, A. M., Lightsey, H. M., Simpson, A. K., Schoenfeld, A. J. 2022; 22 (5): 716-722

  Abstract

  Women represent a small minority of practicing orthopedic surgeons and neurosurgeons, with spine surgery having a disproportionately low representation relative to other subspecialties. Previous efforts have attempted to characterize gender patterns in authorship amongst select spine journals. However, no study to our knowledge has done a comprehensive assessment of the influence of gender on academic productivity, impact, and leadership amongst academic spine faculty.To evaluate the impact of gender on academic productivity, promotion to leadership positions, and career advancement among academic spine faculty in the United States.Cross-sectional study.Academic spine faculty associated with orthopedic residency, North American Spine Society spine fellowship programs, and American Association of Neurological Surgeons spine fellowship programs.Academic productivity as measured by publications counts, h-index, authorship ranking as well as academic rank and leadership roles METHODS: We identified all spine faculty across orthopedic residency, orthopedic spine fellowship, and neurosurgical spine fellowship programs in the United States, and abstracted academic performance characteristics, cumulative h-index, and complete publication records for each individual faculty member. Proportions of men and women by specialty, academic rank, and leadership were compared with Fisher's exact testing, and comparison of mean h-index and publication counts compared with Wilcoxon rank-sum testing. Adjusted analyses on publication count and h-index were achieved with poisson regression analysis with gender as the primary predictor adjusting for specialty, degrees, academic rank, and seniority based on time since fellowship completion.The representation of women among spine faculty associated with orthopedic residency and North American Spine Society spine fellowship programs was 5.6%. On average, women had 40% fewer total publications (p=.025), h-indices approximately 5 units lower than men (p=.006), 40% fewer total high-impact publications (p=.030), half the senior author publications (p=.005), and half the high-impact senior author publications (p=.007) compared to men. After adjusting for seniority and academic rank, the number of publications in high impact journals no longer differed between men and women, although differences persisted for total publication count and the h-index. Men were significantly more likely to occupy higher academic ranks, with 25.6% of men and 9.5% of women holding the rank of full professor (p=.031), although there was no significant difference in the rate of appointment to leadership positions. Similar findings were encountered among American Association of Neurological Surgeons spine fellowship faculty.The present study details the low rate of women in academic spine surgery. Furthermore, gender disparities exist in publication volume, impact, and h-indices. A much lower proportion of women hold higher-ranking academic positions compared to men, though appointment to leadership positions was similar between genders. Differences in seniority and publication metrics may in part be due to the relatively younger cohort of women faculty. These findings underscore the need for active investment in diversity and pipeline efforts that facilitate recruitment and support academic productivity of women in spine surgery.

  View details for DOI 10.1016/j.spinee.2021.12.003

  View details for Web of Science ID 000847361200003

  View details for PubMedID 34902588

• A Natural History of Patients Treated Operatively and Nonoperatively for Spinal Metastases Over 2 Years Following Treatment Survival and Functional Outcomes SPINE Xiong, G. X., Fisher, M. A., Schwab, J. H., Simpson, A. K., Nguyen, L., Tobert, D. G., Balboni, T. A., Shin, J. H., Ferrone, M. L., Schoenfeld, A. J. 2022; 47 (7): 515-522

  Abstract

  Prospective observational study.We present the natural history, including survival and function, among participants in the prospective observational study of spinal metastases treatment investigation.Surgical treatment has been touted as a means to preserve functional independence, quality of life, and survival. Nearly all prior investigations have been limited by retrospective design and relatively short-periods of post-treatment surveillance.This natural history study was conducted using the records of patients who were enrolled in the prospective observational study of spinal metastases treatment study (2017-2019). Eligible participants were 18 or older and presenting for treatment of spinal metastatic disease. Patients were followed at predetermined intervals (1, 3, 6, 12, and 24-mo) following treatment. We conducted cox proportional hazard regression analysis adjusting for confounders including age, biologic sex, number of comorbidities, type of metastatic lesion, neurologic symptoms at presentation, number of metastases involving the vertebral body, vertebral body collapse, New England Spinal Metastasis Score (NESMS) at presentation, and treatment strategy.We included 202 patients. Twenty-three percent of the population had died by 3 months following treatment initiation, 51% by 1 year, and 70% at 2 years. There was no significant difference in survival between patients treated operatively and nonoperatively (P = 0.16). No significant difference in HRQL between groups was appreciated beyond 3 months following treatment initiation. NESMS at presentation (scores of 0 [HR 5.61; 95% CI 2.83, 11.13] and 1 [HR 3.00; 95% CI 1.60, 5.63]) was significantly associated with mortality.We found that patients treated operatively and nonoperatively for spinal metastases benefitted from treatment in terms of HRQL. Two-year mortality for the cohort as a whole was 70%. When prognosticating survival, the NESMS appears to be an effective utility, particularly among patients with scores of 0 or 1.Level of Evidence: 2.

  View details for DOI 10.1097/BRS.0000000000004322

  View details for Web of Science ID 000768449800008

  View details for PubMedID 35066537

  View details for PubMedCentralID PMC8923973

• Microendoscopic decompression of conjoined lumbosacral nerve roots BMJ CASE REPORTS Lightsey, H. M., Xiong, G. X., Schoenfeld, A. J., Simpson, A. K. 2022; 15 (3)

  Abstract

  Nerve root morphological variability is often incompletely appreciated on preoperative imaging and can complicate intraoperative decision-making. This case demonstrates the utility of spinal endoscopy in the visualisation and manipulation of conjoined nerve roots and includes procedural images to promote better understanding and awareness of this anatomical anomaly. A woman in her 50s presented with 1 year of progressive left S1 radiculopathy refractory to non-operative modalities. History and examination were notable for S1 dermatomal paresthesias, positive ipsilateral straight leg raise and grade 4/5 gastrocnemius strength. MRI demonstrated an L5-S1 left paracentral disc herniation causing severe lateral recess stenosis. Endoscopic decompression revealed conjoined lumbosacral nerve roots. Laminotomies and discectomy provided circumferential decompression. The patient experienced immediate and sustained relief of her preoperative radiculopathy as manifested in patient-reported outcome measures. Evolving endoscopic spine platforms provide novel visualisation of nerve root anomalies yielding new insight on safe and effective decompressive techniques.

  View details for DOI 10.1136/bcr-2021-248680

  View details for Web of Science ID 000772460000021

  View details for PubMedID 35296497

  View details for PubMedCentralID PMC8928263

• Does Operative Management of Epidural Abscesses Increase Healthcare Expenditures up to 1 Year After Treatment? CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Xiong, G. X., Crawford, A. M., Goh, B. C., Striano, B. M., Bensen, G. P., Schoenfeld, A. J. 2022; 480 (2): 382-392

  View details for DOI 10.1097/CORR.0000000000001967

  View details for Web of Science ID 000746119900027

• Spinal endoscopy: evidence, techniques, global trends, and future projections SPINE JOURNAL Simpson, A. K., Lightsey, H. M., Xiong, G. X., Crawford, A. M., Minamide, A., Schoenfeld, A. J. 2022; 22 (1): 64-74

  View details for DOI 10.1016/j.spinee.2021.07.004

  View details for Web of Science ID 000732684800007

• Nasal screening for methicillin-resistant <i>Staphylococcus aureus</i> does not reduce surgical site infection after primary lumbar fusion SPINE JOURNAL Xiong, G. X., Greene, N. E., Hershman, S. H., Schwab, J. H., Bono, C. M., Tobert, D. G. 2022; 22 (1): 113-125

  View details for DOI 10.1016/j.spinee.2021.07.008

  View details for Web of Science ID 000732684800012

• The NIMS framework: an approach to the evaluation and management of epidural abscesses SPINE JOURNAL Xiong, G. X., Crawford, A. M., Striano, B., Lightsey, H. M., Nelson, S. B., Schwab, J. H. 2021; 21 (12): 1965-1972

  View details for DOI 10.1016/j.spinee.2021.05.012

  View details for Web of Science ID 000726809900002

  View details for PubMedID 34010684

• Comparison of Radiation Exposure Between Anterior, Lateral, and Posterior Interbody Fusion Techniques and the Influence of Patient and Procedural Factors SPINE Striano, B. M., Xiong, G. X., Lightsey, H. M., Crawford, A. M., Pisano, A. J., Schoenfeld, A. J., Simpson, A. K. 2021; 46 (23): 1669-1675

  Abstract

  Retrospective cohort.The aim of this study was to elucidate the relative influence of multiple factors on radiation usage for anterior, lateral, and posterior based lumbar interbody fusion techniques.There has been substantial global growth in the performance of lumbar interbody fusions, due to evolution of techniques and approaches and increased attention to sagittal alignment. Utilization of intraoperative imaging guidance has similarly expanded, with a predominance of fluoroscopy and consequent increased radiation exposure. There have been no larger-scale studies examining the role of patient and procedural factors in driving radiation exposure across different interbody techniques.We used a clinical registry to review all single-level lumbar interbody fusions performed between January 2016 and October 2020. Operative records were reviewed for the amount of radiation exposure during the procedure. Patient age, biologic sex, body mass index (BMI), operative surgeon, surgical level, surgical time, and fusion technique were recorded. Multivariable adjusted analyses using negative binomial regression were used to account for confounding.We included 134 interbody fusions; 80 performed with a posterior approach (TLIF/PLIF), 43 via an anterior approach (ALIF) with posterior pedicle fixation, and 9 performed with a lateral approach (LLIF/XLIF). Average radiation per case was 136.4 mGy (SE 17.3) for ALIF, 108.6 mGy (16.9) for LLIF/XLIF, and 60.5 mGy (7.4) for TLIF/PLIF. We identified lateral approaches, increased BMI, minimally invasive techniques, and more caudal operative levels as significantly associated with increased radiation exposure.We identified several novel drivers of radiation exposure during interbody fusion procedures, including the relative importance of technique and the level at which the fusion is performed. More caudal levels of intervention and lateral based techniques had significantly greater radiation exposure.Level of Evidence: 4.

  View details for DOI 10.1097/BRS.0000000000004247

  View details for Web of Science ID 000715393100023

  View details for PubMedID 34610614

• Open epidural blood patch to augment durotomy repair in lumbar spine surgery: surgical technique and cohort study SPINE JOURNAL Xiong, G. X., Tobert, D., Fogel, H., Cha, T., Schwab, J., Shin, J., Bono, C., Hershman, S. 2021; 21 (12): 2010-2018

  Abstract

  Incidental durotomy during elective spine surgery is relatively common. While usually benign and self-limited, it can be associated with morbidity, increased cost, and medicolegal ramifications. Dural repair typically involves performing a primary closure using a suture or dural staple; repairs are then frequently augmented with a sealant, patch, or fat/fascial graft. Although primary repair of an incidental durotomy is standard practice, the ideal secondary sealant or augment choice remains unclear. A wide variety of commercially available dural sealant options exist, and while none have demonstrated consistent superiority, all are associated with single-use costs in the hundreds to thousands of dollars and have concerns regarding swelling, local inflammation, or short-lived dural adherence.The goal of this study is to compare the results of dural repair augmentation using an open intraoperative epidural blood patch to a hydrogel technique.Retrospective comparative cohort study at an academic referral center PATIENT SAMPLE: Adult patients undergoing lumbar spine surgery from March 2017 to January 2021 who sustained an incidental durotomy. Patients undergoing surgery for infection were excluded.The primary outcome was failure of the repair as determined by a return to the operating room for re-exploration of a persistent cerebrospinal fluid (CSF) leak within 30 days of the index procedure. A secondary outcome was the incidence of a postoperative positional headache, and if present, the method used to obtain resolution. The primary predictor was use of a suture and hydrogel technique ("hydrogel" group), or the use of an epidural blood patch ("EBP" group).The method for applying an open epidural blood patch is presented in detail and involves primarily repairing the durotomy followed by allowing whole blood to pool and clot in the operative field until the durotomy is completely covered. This was compared with a group of patients undergoing secondary augmentation with commercially available hydrogel. In both groups, mechanical resistance to CSF leakage was confirmed with direct visualization and a Valsalva maneuver, respectively. Patients were instructed to remain flat until the morning after surgery. Chart review was used for data abstraction on preoperative, demographic, perioperative, and postoperative clinical factors. To compare between the hydrogel and EBP group, Wilcoxon rank-sum testing was used to test for non-parametric comparisons of means, and chi-square testing between binomial data.Of 732 patients during the study period, forty-eight patients met study criteria. Twenty-five patients were in the hydrogel group and 23 in the EBP group. Mean age was 69.3 years (standard error 1.3 years). Patients were predominantly female (n = 31, 64.6%) with a mean BMI of 29.5 (SE 0.8), with no significant baseline differences between the hydrogel and EBP groups. Two patients in the hydrogel group (8.0%) and two in the EBP group (8.7%) had mild positional headaches postoperatively that resolved without intervention within 24 hours. One (4.3%) patient in the EBP group had positional headaches following an initial headache-free period; this patient was returned to the operating room and no evidence of a persistent CSF leak was found despite meticulous exploration.An open, intraoperatively placed epidural blood patch may be an efficacious and cost-effective way to manage an incidental durotomy. This method merits further study as an allergy-free, no swell, cost-neutral method of dural repair augmentation.

  View details for DOI 10.1016/j.spinee.2021.06.011

  View details for Web of Science ID 000726809900007

  View details for PubMedID 34144204

• Telemedicine Use in Orthopaedic Surgery Varies by Race, Ethnicity, Primary Language, and Insurance Status CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Xiong, G., Greene, N. E., Lightsey, H. M., Crawford, A. M., Striano, B. M., Simpson, A. K., Schoenfeld, A. J. 2021; 479 (7): 1417-1425

  Abstract

  Healthcare disparities are well documented across multiple subspecialties in orthopaedics. The widespread implementation of telemedicine risks worsening these disparities if not carefully executed, despite original assumptions that telemedicine improves overall access to care. Telemedicine also poses unique challenges such as potential language or technological barriers that may alter previously described patterns in orthopaedic disparities.Are the proportions of patients who use telemedicine across orthopaedic services different among (1) racial and ethnic minorities, (2) non-English speakers, and (3) patients insured through Medicaid during a 10-week period after the implementation of telemedicine in our healthcare system compared with in-person visits during a similar time period in 2019?This was a retrospective comparative study using electronic medical record data to compare new patients establishing orthopaedic care via outpatient telemedicine at two academic urban medical centers between March 2020 and May 2020 with new orthopaedic patients during the same 10-week period in 2019. A total of 11,056 patients were included for analysis, with 1760 in the virtual group and 9296 in the control group. Unadjusted analyses demonstrated patients in the virtual group were younger (median age 57 years versus 59 years; p < 0.001), but there were no differences with regard to gender (56% female versus 56% female; p = 0.66). We used self-reported race or ethnicity as our primary independent variable, with primary language and insurance status considered secondarily. Unadjusted and multivariable adjusted analyses were performed for our primary and secondary predictors using logistic regression. We also assessed interactions between race or ethnicity, primary language, and insurance type.After adjusting for age, gender, subspecialty, insurance, and median household income, we found that patients who were Hispanic (odds ratio 0.59 [95% confidence interval 0.39 to 0.91]; p = 0.02) or Asian were less likely (OR 0.73 [95% CI 0.53 to 0.99]; p = 0.04) to be seen through telemedicine than were patients who were white. After controlling for confounding variables, we also found that speakers of languages other than English or Spanish were less likely to have a telemedicine visit than were people whose primary language was English (OR 0.34 [95% CI 0.18 to 0.65]; p = 0.001), and that patients insured through Medicaid were less likely to be seen via telemedicine than were patients who were privately insured (OR 0.83 [95% CI 0.69 to 0.98]; p = 0.03).Despite initial promises that telemedicine would help to bridge gaps in healthcare, our results demonstrate disparities in orthopaedic telemedicine use based on race or ethnicity, language, and insurance type. The telemedicine group was slightly younger, which we do not believe undermines the findings. As healthcare moves toward increased telemedicine use, we suggest several approaches to ensure that patients of certain racial, ethnic, or language groups do not experience disparate barriers to care. These might include individual patient- or provider-level approaches like expanded telemedicine schedules to accommodate weekends and evenings, institutional investment in culturally conscious outreach materials such as advertisements on community transport systems, or government-level provisions such as reimbursement for telephone-only encounters.Level III, therapeutic study.

  View details for DOI 10.1097/CORR.0000000000001775

  View details for Web of Science ID 000711678900003

  View details for PubMedID 33982979

  View details for PubMedCentralID PMC8208394

• Interventional procedure plans generated by telemedicine visits in spine patients are rarely changed after in-person evaluation REGIONAL ANESTHESIA AND PAIN MEDICINE Crawford, A. M., Lightsey, H. M., Xiong, G. X., Striano, B. M., Greene, N., Schoenfeld, A. J., Simpson, A. K. 2021; 46 (6): 478-481

  View details for DOI 10.1136/rapm-2021-102630

  View details for Web of Science ID 000656619400004

• Variability and contributions to cost associated with anterior versus posterior approaches to lumbar interbody fusion CLINICAL NEUROLOGY AND NEUROSURGERY Crawford, M., Lightsey, M., Xiong, X., Striano, M., Pisano, J., Schoenfeld, J., Simpson, K. 2021; 206: 106688

  Abstract

  Lumbar interbody fusions are being performed with increased frequency in the last decade. Anterior and posterior interbody techniques have demonstrated relatively similar success rates. Nonetheless, despite increased attention to cost-effective care delivery, approach-related differences in procedural cost and predictors for these differences remain poorly defined. The purpose of this investigation was to characterize the variability in cost for anterior versus posterior-based lumbar interbody fusions and to identify key predictors of procedural cost.We evaluated the records of all patients who underwent a primary anterior (ALIF) or posterior/transforaminal (PLIF/TLIF) lumbar interbody fusion with concomitant posterior fusion from 2016 to 2020 at four hospitals in a major metropolitan area. We reviewed the records of all included patients and abstracted demographics, insurance status, approach, operative time, diagnosis, surgeon, institution, open versus minimally invasive technique, and components of procedural costs. Costs based upon interbody approach were compared via multivariable adjusted analyses using negative binomial regression.We included 139 interbody fusion procedures; 98 were performed via posterior approach (TLIF/PLIF) and 41 using an anterior approach. Anterior techniques were associated with significantly increased costs as compared to posterior procedures (anterior, $16316 [SE 556] vs. posterior, $9415 [SE 345]; p < 0.001). This determination remained significant following multivariable adjusted analysis (regression coefficient -0.22, 95% CI -0.34, -0.10, p < 0.001). Multivariable analysis also indicated that surgeon, invasiveness, and procedure time were significant predictors of total cost.Our findings demonstrate that anterior interbody techniques are, on average, 173% (anterior, $16316 [SE 556] vs. posterior, $9415 [SE 345]; p < 0.001) more expensive than posterior-based procedures. Given the relative equipoise of these different approaches for many clinical applications, these findings should be considered in an ecosystem increasingly attentive to cost effective care delivery. This work has also provided specific procedural variables for surgeons and systems to target when optimizing procedural costs.

  View details for DOI 10.1016/j.clineuro.2021.106688

  View details for Web of Science ID 000722581600013

  View details for PubMedID 34015696

• Telemedicine visits generate accurate surgical plans across orthopaedic subspecialties ARCHIVES OF ORTHOPAEDIC AND TRAUMA SURGERY Crawford, A. M., Lightsey, H. M., Xiong, G. X., Striano, B. M., Schoenfeld, A. J., Simpson, A. K. 2022; 142 (11): 3009-3016

  View details for DOI 10.1007/s00402-021-03903-2

  View details for Web of Science ID 000640946300002

• Vancomycin-impregnated calcium sulfate beads compared with vancomycin powder in adult spinal deformity patients undergoing thoracolumbar fusion. North American Spine Society journal Xiong, G., Fogel, H., Tobert, D., Cha, T., Schwab, J., Bono, C., Hershman, S. 2021; 5: 100048

  Abstract

  INTRODUCTION: Adult spinal deformity (ASD) surgery patients are at higher risk for surgical site infections (SSIs) due to large incisions, high blood loss, long surgical duration, and extensive instrumentation. The use of vancomycin powder has demonstrated inconsistent results in ASD surgery. Antibiotic-impregnated calcium sulfate beads have been used in arthroplasty and foot and ankle surgery with promising results. The purpose of this study was to provide preliminary data on the use of vancomycin-impregnated calcium sulfate beads in the prevention of SSI following ASD surgery and provide comparisons to the use of vancomycin powder.METHODS: A retrospective chart review was performed for 95 consecutive surgical ASD patients at a tertiary care center from January 2017 until March 2020. Patients received either vancomycin powder (powder group) or vancomycin-impregnated calcium sulfate beads (bead group) intrawound prior to closure. Patient demographics, operative course, and incidence of postoperative infections were recorded. A two-tailed chi-squared test was performed to compare infection rates.RESULTS: Ninety-five patients were included for review. Forty-two patients were in the powder group and 53 patients were in the bead group. The bead group was older (59.8vs 67.8 years, p < 0.01) with similar BMI and rates of diabetes, smoking, and length of surgery. There were four postoperative SSI in the powder group requiring operative irrigation and debridement and one SSI in the bead group (9.5% vs 1.9%, p=0.09). All infections occurred in the first 90 days of the postoperative period.CONCLUSION: Preliminary examination of the use of vancomycin-impregnated calcium sulfate beads demonstrated a 1.9% surgical site infection rate in adult spinal deformity surgical patients, which was not significantly different compared with the 9.5% infection rate in patients who received vancomycin powder. Prospective study is needed to determine if the differences found are significant in a larger number of patients.

  View details for DOI 10.1016/j.xnsj.2020.100048

  View details for PubMedID 35141614

• Surgical plans generated from telemedicine visits are rarely changed after in-person evaluation in spine patients SPINE JOURNAL Lightsey, H. M., Crawford, A. M., Xiong, G. X., Schoenfeld, A. J., Simpson, A. K. 2021; 21 (3): 359-365

  Abstract

  The role of telemedicine within the realm of spine surgery is evolving, catalyzed by the recent pandemic. Specifically, the capability of this technology to provide high-quality, cost-effective care without an in-person interaction and physical examination remains poorly defined.To characterize the impact of telemedicine on spine surgical planning by assessing whether surgical plans established in virtual visits changed following in-person evaluation.Retrospective cohort study.We evaluated the records of patients who were indicated for surgery with documented specific surgical plans during a virtual encounter (March-July 2020) and underwent subsequent in-person evaluation prior to surgery.We determined whether surgical plans changed between the virtual encounter and the in-person interaction. Secondarily, we reviewed use of the virtual physical examination across surgeons.We reviewed virtual and in-person clinical encounters from a single academic spine division, evaluating those patients who were seen exclusively via telemedicine encounters and indicated for surgery with documented specific surgical plans. These plans were compared to the surgical plan after these same patients underwent in-person evaluation. Demographic data, patient primary complaint, and the type and extent of physical examination performed by the surgeon were recorded.Of the 33 patients included, the surgical plan did not change among 31 individuals (94%) following in-person interaction. For the two patients where surgical plans were modified, multilevel fusions were increased by one level. There was notable inter- and intra-surgeon variability with regard to the use of virtual physical exams.Our findings suggest that telemedicine evaluations are efficient means of preoperative assessment of spine patients and delineation of surgical plans. These results may support innovations that can optimize access to care for patients.

  View details for DOI 10.1016/j.spinee.2020.11.009

  View details for Web of Science ID 000618676400001

  View details for PubMedID 33227550

• Bisphosphonates and parathyroid hormone analogs for improving bone quality in spinal fusion: State of evidence ORTHOPEDIC REVIEWS Atesok, K., Stippler, M., Striano, B. M., Xiong, G., Lindsey, M., Cappellucci, E., Psilos, A., Richter, S., Heffernan, M. J., Theiss, S., Papavassiliou, E. 2020; 12 (2): 64-70

  Abstract

  Spinal fusion is among the most commonly performed surgical procedures for elderly patients with spinal disorders - including degenerative disc disease with spondylolisthesis, deformities, and trauma. With the large increase in the aging population and the prevalence of osteoporosis, the number of elderly osteoporotic patients needing spinal fusion has risen dramatically. Due to reduced bone quality, postoperative complications such as implant failures, fractures, post-junctional kyphosis, and pseudarthrosis are more commonly seen after spinal fusion in osteoporotic patients. Therefore, pharmacologic treatment strategies to improve bone quality are commonly pursued in osteoporotic cases before conducting spinal fusions. The two most commonly used pharmacotherapeutics are bisphosphonates and parathyroid hormone (PTH) analogs. Evidence indicates that using bisphosphonates and PTH analogs, alone or in combination, in osteoporotic patients undergoing spinal fusion, decreases complication rates and improves clinical outcomes. Further studies are needed to develop guidelines for the administration of bisphosphonates and PTH analogs in osteoporotic spinal fusion patients in terms of treatment duration, potential benefits of sequential use, and the selection of either therapeutic agents based on patient characteristics.

  View details for DOI 10.4081/or.2020.8590

  View details for Web of Science ID 000593121000004

  View details for PubMedID 32922704

  View details for PubMedCentralID PMC7461648

• Decreased estimated blood loss in lateral trans-psoas versus anterior approach to lumbar interbody fusion for degenerative spondylolisthesis. Journal of spine surgery (Hong Kong) Goodnough, L. H., Koltsov, J., Wang, T., Xiong, G., Nathan, K., Cheng, I. 2019; 5 (2): 185–93

  Abstract

  Background: The goal of the current study was to compare the perioperative and post-operative outcomes of eXtreme lateral trans-psoas approach (XLIF) versus anterior lumbar interbody fusion (ALIF) for single level degenerative spondylolisthesis. The ideal approach for degenerative spondylolisthesis remains controversial.Methods: Consecutive patients undergoing single level XLIF (n=21) or ALIF (n=54) for L4-5 degenerative spondylolisthesis between 2008-2012 from a single academic center were retrospectively reviewed. Groups were compared for peri-operative data (estimated blood loss, operative time, adjunct procedures or additional implants), radiographic measurements (L1-S1 cobb angle, disc height, fusion grade, subsidence), 30-day complications (infection, DVT/PE, weakness/paresthesia, etc.), and patient reported outcomes (leg and back Numerical Rating Scale, and Oswestry Disability Index).Results: Estimated blood loss was significantly lower for XLIF [median 100; interquartile range (IQR), 50-100 mL] than for ALIF (median 250; IQR, 150-400 mL; P<0.001), including after adjusting for significantly higher rates of posterior decompression in the ALIF group. There were no significant differences in rates of complications within 30 days, radiographic outcomes, or in re-operation rates. Both groups experienced significant pain relief post-operatively.Conclusions: The lateral trans-psoas approach is associated with diminished blood loss compared to the anterior approach in the treatment of degenerative spondylolisthesis. We were unable to detect differences in radiographic outcomes, complication rates, or patient reported outcomes. Continued efforts to directly compare approaches for specific indications will minimize complications and improve outcomes. Further studies will continue to define indications for lateral versus anterior approach to lumbar spine for degenerative spondylolisthesis.

  View details for DOI 10.21037/jss.2019.05.08

  View details for PubMedID 31380471

• What Is the State of Quality Measurement in Spine Surgery? CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Bennett, C., Xiong, G., Hu, S., Wood, K., Kamal, R. N. 2018; 476 (4): 725–31

  Abstract

  Value-based healthcare models rely on quality measures to evaluate the efficacy of healthcare delivery and to identify areas for improvement. Quality measure research in other areas of health care has generally shown that there is a limited number of available quality measures and that those that exist disproportionately focus on processes as opposed to outcomes. The purpose of this study was to assess the current state of quality measures and candidate quality measures in spine surgery.(1) How many quality measures and candidate quality measures are currently available? (2) According to Donabedian domains and National Quality Strategy (NQS) priorities, what aspects or domains of care do the present quality measures and candidate quality measures represent?We systematically reviewed the National Quality Forum, the Agency for Healthcare Research and Quality, and the Physician Quality Reporting System for quality measures relevant to spine surgery. A systematic search for candidate quality measures was also performed using MEDLINE/PubMed and Embase as well as publications from the American Academy of Orthopaedic Surgeons, Congress of Neurological Surgeons, and the North American Spine Society. Clinical practice guidelines were included as candidate quality measures if their development was in accordance with Institute of Medicine criteria for the development of clinical practice guidelines, they were based on consistent clinical evidence including at least one Level I study, and they carried the strongest possible recommendation by the developing body. Quality measures and candidate quality measures were then pooled for analysis and categorized by clinical focus, NQS priority, and Donabedian domain. Our initial search yielded a total of 3940 articles, clinical practice guidelines, and quality measures, 74 of which met criteria for inclusion in this study.Of the 74 measures studied, 29 (39%) were quality measures and 45 (61%) were candidate quality measures. Fifty of 74 (68%) were specific to the care of the spine, and 24 of 74 (32%) were related to the general care of spine patients. The majority of the spine-specific measures were process measures (45 [90%]) and focused on the NQS priority of "Effective Clinical Care" (44 [88%]). The majority of the general care measures were also process measures (14 [58%]), the highest portion of which focused on the NQS priority of "Patient Safety" (10 [42%]).Given the large number of pathologies treated by spine surgeons, the limited number of available quality measures and candidate quality measures in spine surgery is inadequate to support the transition to a value-based care model. Additionally, current measures disproportionately focus on certain aspects or domains of care, which may hinder the ability to appropriately judge an episode of care, extract usable data, and improve quality. Physicians can steward the creation of meaningful quality measures by participating in clinical practice guideline development, assisting with the creation and submission of formal quality measures, and conducting the high-quality research on which effective guidelines and quality measures depend.

  View details for PubMedID 29480884

• Men and Women Differ in the Biochemical Composition of Platelet-Rich Plasma AMERICAN JOURNAL OF SPORTS MEDICINE Xiong, G., Lingampalli, N., Koltsov, J. B., Leung, L. L., Bhutani, N., Robinson, W. H., Chu, C. R. 2018; 46 (2): 409–19

  Abstract

  Autologous platelet-rich plasma (PRP) is widely used for a variety of clinical applications. However, clinical outcome studies have not consistently shown positive effects. The composition of PRP differs based on many factors. An improved understanding of factors influencing the composition of PRP is important for the optimization of PRP use.Age and sex influence the PRP composition in healthy patients.Controlled laboratory study.Blood from 39 healthy patients was collected at a standardized time and processed into leukocyte-poor PRP within 1 hour of collection using the same laboratory centrifuge protocol and frozen for later analysis. Eleven female and 10 male patients were "young" (aged 18-30 years), while 8 male and 10 female patients were "older" (aged 45-60 years). Thawed PRP samples were assessed for cytokine and growth factor levels using a multiplex assay and enzyme-linked immunosorbent assay. The platelet count and high-sensitivity C-reactive protein levels were measured. Two-way analysis of variance determined age- and sex-based differences.Platelet and high-sensitivity C-reactive protein concentrations were similar in PRP between the groups ( P = .234). Male patients had higher cytokine and growth factor levels in PRP compared with female patients for inflammatory cytokines such as interleukin-1 beta (IL-1β) (9.83 vs 7.71 pg/mL, respectively; P = .008) and tumor necrosis factor-alpha (TNF-α) (131.6 vs 110.5 pg/mL, respectively; P = .048); the anti-inflammatory IL-1 receptor antagonist protein (IRAP) (298.0 vs 218.0 pg/mL, respectively; P < .001); and growth factors such as fibroblast growth factor-basic (FGF-basic) (237.9 vs 194.0 pg/mL, respectively; P = .01), platelet-derived growth factor (PDGF-BB) (3296.2 vs 2579.3 pg/mL, respectively; P = .087), and transforming growth factor-beta 1 (TGF-β1) (118.8 vs 92.8 ng/mL, respectively; P = .002). Age- but not sex-related differences were observed for insulin-like growth factor-1 (IGF-1) ( P < .001). Age and sex interaction terms were not significant. While mean differences were significant, there was also substantial intragroup variability.This study in healthy patients shows differences in the composition of PRP between men and women, with sex being a greater factor than age. There was also proteomic variability within the groups. These data support a personalized approach to PRP treatment and highlight the need for a greater understanding of the relationships between proteomic factors in PRP and clinical outcomes.Variability in the proteomic profile of PRP may affect tissue and clinical responses to treatment. These data suggest that clinical studies should account for the composition of PRP used.

  View details for PubMedID 29211968

• Providing Specialty Care for the Poor and Underserved at Student-Run Free Clinics in the San Francisco Bay Area. Journal of health care for the poor and underserved Liu, M. B., Xiong, G. n., Boggiano, V. L., Ye, P. P., Lin, S. n. 2017; 28 (4): 1276–85

  Abstract

  This report describes the model of specialty clinics implemented at Stanford University's two student-run free clinics, Arbor Free Clinic and Pacific Free Clinic, in the San Francisco Bay Area. We describe our patient demographic characteristics and the specialty services provided. We discuss challenges in implementing specialty care at student-run free clinics.

  View details for DOI 10.1353/hpu.2017.0113

  View details for PubMedID 29176094

• Metabolomic profiling in the prediction of gestational diabetes mellitus. Diabetologia Bentley-Lewis, R., Huynh, J., Xiong, G., Lee, H., Wenger, J., Clish, C., Nathan, D., Thadhani, R., Gerszten, R. 2015; 58 (6): 1329-32

  Abstract

  Metabolomic profiling in populations with impaired glucose tolerance has revealed that branched chain and aromatic amino acids (BCAAs) are predictive of type 2 diabetes. Because gestational diabetes mellitus (GDM) shares pathophysiological similarities with type 2 diabetes, the metabolite profile predictive of type 2 diabetes could potentially identify women who will develop GDM.We conducted a nested case-control study of 18- to 40-year-old women who participated in the Massachusetts General Hospital Obstetrical Maternal Study between 1998 and 2007. Participants were enrolled during their first trimester of a singleton pregnancy and fasting serum samples were collected. The women were followed throughout pregnancy and identified as having GDM or normal glucose tolerance (NGT) in the third trimester. Women with GDM (n = 96) were matched to women with NGT (n = 96) by age, BMI, gravidity and parity. Liquid chromatography-mass spectrometry was used to measure the levels of 91 metabolites.Data analyses revealed the following characteristics (mean ± SD): age 32.8 ± 4.4 years, BMI 28.3 ± 5.6 kg/m(2), gravidity 2 ± 1 and parity 1 ± 1. Six metabolites (anthranilic acid, alanine, glutamate, creatinine, allantoin and serine) were identified as having significantly different levels between the two groups in conditional logistic regression analyses (p < 0.05). The levels of the BCAAs did not differ significantly between GDM and NGT.Metabolic markers identified as being predictive of type 2 diabetes may not have the same predictive power for GDM. However, further study in a racially/ethnically diverse population-based cohort is necessary.

  View details for DOI 10.1007/s00125-015-3553-4

  View details for PubMedID 25748329

  View details for PubMedCentralID PMC4428592

• A systematic review of metabolite profiling in gestational diabetes mellitus. Diabetologia Huynh, J., Xiong, G., Bentley-Lewis, R. 2014; 57 (12): 2453-64

  Abstract

  Gestational diabetes mellitus is associated with adverse maternal and fetal outcomes during, as well as subsequent to, pregnancy, including increased risk of type 2 diabetes and cardiovascular disease. Because of the importance of early risk stratification in preventing these complications, improved first-trimester biomarker determination for diagnosing gestational diabetes would enhance our ability to optimise both maternal and fetal health. Metabolomic profiling, the systematic study of small molecule products of biochemical pathways, has shown promise in the identification of key metabolites associated with the pathogenesis of several metabolic diseases, including gestational diabetes. This article provides a systematic review of the current state of research on biomarkers and gestational diabetes and discusses the clinical relevance of metabolomics in the prediction, diagnosis and management of gestational diabetes.We conducted a systematic search of MEDLINE (PubMed) up to the end of February 2014 using the key term combinations of 'metabolomics,' 'metabonomics,' 'nuclear magnetic spectroscopy,' 'mass spectrometry,' 'metabolic profiling' and 'amino acid profile' combined (AND) with 'gestational diabetes'. Additional articles were identified through searching the reference lists from included studies. Quality assessment of included articles was conducted through the use of QUADOMICS.This systematic review included 17 articles. The biomarkers most consistently associated with gestational diabetes were asymmetric dimethylarginine and NEFAs. After QUADOMICS analysis, 13 of the 17 included studies were classified as 'high quality'.Existing metabolomic studies of gestational diabetes present inconsistent findings regarding metabolite profile characteristics. Further studies are needed in larger, more racially/ethnically diverse populations.

  View details for DOI 10.1007/s00125-014-3371-0

  View details for PubMedID 25193282

  View details for PubMedCentralID PMC4221524

• Center of mass motion in swimming fish: effects of speed and locomotor mode during undulatory propulsion ZOOLOGY Xiong, G., Lauder, G. V. 2014; 117 (4): 269-281

  Abstract

  Studies of center of mass (COM) motion are fundamental to understanding the dynamics of animal movement, and have been carried out extensively for terrestrial and aerial locomotion. But despite a large amount of literature describing different body movement patterns in fishes, analyses of how the center of mass moves during undulatory propulsion are not available. These data would be valuable for understanding the dynamics of different body movement patterns and the effect of differing body shapes on locomotor force production. In the present study, we analyzed the magnitude and frequency components of COM motion in three dimensions (x: surge, y: sway, z: heave) in three fish species (eel, bluegill sunfish, and clown knifefish) swimming with four locomotor modes at three speeds using high-speed video, and used an image cross-correlation technique to estimate COM motion, thus enabling untethered and unrestrained locomotion. Anguilliform swimming by eels shows reduced COM surge oscillation magnitude relative to carangiform swimming, but not compared to knifefish using a gymnotiform locomotor style. Labriform swimming (bluegill at 0.5 body lengths/s) displays reduced COM sway oscillation relative to swimming in a carangiform style at higher speeds. Oscillation frequency of the COM in the surge direction occurs at twice the tail beat frequency for carangiform and anguilliform swimming, but at the same frequency as the tail beat for gymnotiform locomotion in clown knifefish. Scaling analysis of COM heave oscillation for terrestrial locomotion suggests that COM heave motion scales with positive allometry, and that fish have relatively low COM oscillations for their body size.

  View details for DOI 10.1016/j.zoo1.2014.03.002

  View details for Web of Science ID 000340977600007

  View details for PubMedID 24925455

• Metabolomic Analysis Reveals Amino Acid Responses to an Oral Glucose Tolerance Test in Women with Prior History of Gestational Diabetes Mellitus. Journal of clinical & translational endocrinology Bentley-Lewis, R., Xiong, G., Lee, H., Yang, A., Huynh, J., Kim, C. 2014; 1 (2): 38-43

  Abstract

  Although gestational diabetes mellitus (GDM) is associated with an increased risk of type 2 diabetes mellitus (T2DM) compared to normoglycemic pregnancies, the biochemical pathways underlying the progression of GDM to T2DM are not fully elucidated. The purpose of this exploratory study was to utilize metabolomics with an oral glucose tolerance test (OGTT) to examine the amino acid response in women with prior GDM to determine if a relationship between these metabolites and established risk factors for T2DM exists.Thirty-eight non-pregnant women without diabetes but with prior GDM within the previous 3 years were recruited from a community-based population. A 75 g-OGTT was administered; fasting and 2-hr plasma samples were obtained. Metabolite profiles of 23 amino acids or amino acid derivatives were measured with gas chromatography-mass spectrometry. Measures of insulin resistance were derived from the OGTT and risk factors for T2DM were obtained by self-report.Twenty-two metabolite levels decreased significantly in response to the OGTT (p<0.05). The clinical covariates most powerfully associated with metabolite level changes included race, body mass index (BMI), and duration of prior breastfeeding, (mean ± SD of standardized β-coefficients, β = -0.38 ± 0.05, 0.25 ± 0.08, and 0.44 ± 0.03, respectively, all p<0.05). Notably, a prior history of breastfeeding was associated with the greatest number of metabolite changes.Greater change in metabolite levels after a glucose challenge was significantly associated with a longer duration of breastfeeding and higher BMI. Further exploration of these preliminary observations and closer examination of the specific pathways implicated are warranted.

  View details for DOI 10.1016/j.jcte.2014.03.003

  View details for PubMedID 24932438

  View details for PubMedCentralID PMC4052833