Racial and Social Determinants of Health Disparities in Spine Surgery Affect Preoperative Morbidity and Postoperative Patient Reported Outcomes: Retrospective Observational Study.

STUDY DESIGN: Retrospective observational study. OBJECTIVE: To elucidate racial and socioeconomic factors driving preoperative disparities in spine surgery patients. SUMMARY OF BACKGROUND DATA: There are racial and socioeconomic disparities in preoperative health among spine surgery patients, which may influence outcomes for minority and low socioeconomic status (SES) populations. METHODS: Presenting, postoperative day 90 (POD90), and 12-month (12M) outcome scores (PROMIS global physical and mental [GPH, GMH] and visual analog scale pain [VAS]) were collected for patients undergoing deformity arthrodesis or cervical, thoracic, or lumbar laminotomy or decompression/fusion; these procedures were the most common in our cohort. Social determinants of health for a patient's neighborhood (county, zip code, or census tract) were extracted from public databases. Multivariable linear regression with stepwise selection was used to quantify the association between a patient's preoperative GPH score and sociodemographic variables. RESULTS: Black patients presented with 1 to 3 point higher VAS pain scores (7-8 vs. 5-6) and lower (worse) GPH scores (6.5-10 vs. 11-12) than White patients (P < 0.05 for all comparisons); similarly, lower SES patients presented with 1.5 points greater pain (P < 0.0001) and 3.5 points lower GPH (P < 0.0001) than high SES patients. Patients with lowest-quartile presenting GPH scores reported 36.8% and 37.5% lower (worse) POD-90 GMH and GPH scores than the highest quartile, respectively (GMH: 12 vs. 19, P < 0.0001; GPH: 15 vs. 24, P < 0.0001); this trend extended to 12 months (GMH: 19.5 vs. 29.5, P < 0.0001; GPH: 22 vs. 30, P < 0.0001). Reduced access to primary care (B = -1.616, P < 0.0001) and low SES (B = -1.504, P = 0.001), proxied by median household value, were independent predictors of worse presenting GPH scores. CONCLUSION: Racial and socioeconomic disparities in patients' preoperative physical and mental health at presentation for spine surgery are associated adversely with postoperative outcomes. Renewed focus on structural factors influencing preoperative presentation, including timeliness of care, is essential.Level of Evidence: 3.

Postoperative Prescription of Low-dose Narcotics Yields Equivalent Pain Outcomes Compared to High-dose Narcotics in Opioid-naïve Patients Undergoing Spine Surgery.

STUDY DESIGN: Retrospective cohort study at a single institution. Patients undergoing specific, elective spinal procedures between 2012 and 2018. OBJECTIVE: The aim of thi stsudy was to investigate the relationship between opioid prescriptions during the immediate, post-discharge period, and patient-reported pain outcomes. SUMMARY OF BACKGROUND DATA: Medically prescribed opiates contribute to the opioid crisis, manifesting in significant mortality and economic burden. Although opioids are a mainstay of pain amelioration following spinal surgery, prescription practices are heterogeneous. METHODS: Inclusion criteria included: patients who underwent one of 10 spinal procedures (Table 1); patients with preoperative, postoperative day (POD 1, and POD 30 pain scores reported on the visual analog scale (VAS); patients discharged without a complicated perioperative course. Opioids were converted to morphine milligram equivalents per day (MME/day) using a standard reference table. χ2, Kruskal-Wallis, and logistic regression were utilized to investigate associations between clinical variables and postoperative pain scores. Univariate and multivariable linear regression models with Stepwise selection (cut off: P = 0.05) were employed as appropriate on POD 30 VAS pain scores. RESULTS: Smoking status and postoperative LOS were associated with opioid prescription doses. Patients prescribed opioids <40 MME/day, equivalent to five tablets of 5 mg oxycodone/day, showed no significant difference in POD 30 VAS score (ß coefficient: 0.095, P  = 0.752) when compared to patients who received the highest-dose opioids (>80 MME/day-equivalent to 10 tablets of 5 mg oxycodone/day). Adjusted multivariable logistic regression analysis revealed that postoperative opioid dosage/prescription was not a significant predictor of patients reporting at least 50% pain improvement, suggesting that 40 MME/day is sufficient to maintain patient satisfaction. CONCLUSION: Patients receiving the lowest dosage of opioid prescriptions with sufficient nonopiate analgesics did not report worse pain relief at POD 30 compared to those receiving higher opioid prescriptions. In light of the opioid epidemic, this study supports initial dosing recommendations by the American Society for Addiction Medicine.Level of Evidence: 3.

Gli1 Defines a Subset of Fibro-adipogenic Progenitors that Promote Skeletal Muscle Regeneration With Less Fat Accumulation.

Skeletal muscle has remarkable regenerative ability after injury. Mesenchymal fibro-adipogenic progenitors (FAPs) are necessary, active participants during this repair process, but the molecular signatures of these cells and their functional relevance remain largely unexplored. Here, using a lineage tracing mouse model (Gli1-CreER Tomato), we demonstrate that Gli1 marks a small subset of muscle-resident FAPs with elevated Hedgehog (Hh) signaling. Upon notexin muscle injury, these cells preferentially and rapidly expanded within FAPs. Ablation of Gli1+ cells using a DTA mouse model drastically reduced fibroblastic colony-forming unit (CFU-F) colonies generated by muscle cells and impaired muscle repair at 28 days. Pharmacologic manipulation revealed that Gli1+ FAPs rely on Hh signaling to increase the size of regenerating myofiber. Sorted Gli1+ FAPs displayed superior clonogenicity and reduced adipogenic differentiation ability in culture compared to sorted Gli1- FAPs. In a glycerol injury model, Gli1+ FAPs were less likely to give rise to muscle adipocytes compared to other FAPs. Further cell ablation and Hh activator/inhibitor treatments demonstrated their dual actions in enhancing myogenesis and reducing adipogenesis after injury. Examining single-cell RNA-sequencing dataset of FAPs from normal mice indicated that Gli1+ FAPs with increased Hh signaling provide trophic signals to myogenic cells while restrict their own adipogenic differentiation. Collectively, our findings identified a subpopulation of FAPs that play an essential role in skeletal muscle repair. © 2021 American Society for Bone and Mineral Research (ASBMR).