Intradiscal vacuum phenomenon matches lumbar spine degeneration patterns in an ageing population.

PURPOSE: Intra-Discal Vacuum phenomenon (IDVP) is well-recognised, yet poorly visualised and poorly understood radiological finding in disc degeneration, particularly with regard to its role in spinal alignment. CT analysis of the lumbar spine in an aging population aims to identify patterns associated with IDVP including lumbopelvic morphology and associated spinal diagnoses. METHODS: An analysis was performed of an over-60s population sample of 2020 unrelated abdominal CT scans, without acute spinal presentations. Spinal analysis included sagittal lumbopelvic reconstructions to assess for IDVP and pelvic incidence (PI). Subjects with degenerative pathologies, including previous vertebral fractures, auto-fusion, transitional vertebrae, and listhesis, were also selected out and analysed separately. RESULTS: The prevalence of lumbar spine IDVP was 50.3% (955/1898) and increased with age (125 exclusions). This increased in severity towards the lumbosacral junction (L1L2 8.3%, L2L3 10.9%, L3L4 11.5%, L4L5 23.9%, and L5S1 46.3%). A lower PI yielded a higher incidence of IDVP, particularly at L5S1 (p < 0.01). A total of 292 patients had IDVP with additional degenerative pathologies, which were more likely to occur at the level of isthmic spondylolisthesis, adjacent to a previous fracture or suprajacent to a lumbosacral transitional vertebra (p < 0.05). CONCLUSIONS: This study identified the prevalence and severity of IDVP in an aging population. Sagittal patterns that influence the pattern of IVDP, such as pelvic incidence and degenerative pathologies, provide novel insights into the function of aging spines.

Sustainable surgical practices: A comprehensive approach to reducing environmental impact.

This paper presents a comprehensive overview of the environmental impact of surgical procedures and highlights potential strategies to reduce the associated greenhouse gas emissions. We discuss procurement, waste management, and energy consumption, providing examples of successful interventions in each area. We also emphasize the importance of adopting the Green Theatre Checklist as a useful tool for clinicians aiming to implement sustainable surgical practices.

Learning curve analyses in spine surgery: a systematic simulation-based critique of methodologies.

BACKGROUND CONTEXT: Various statistical approaches exist to delineate learning curves in spine surgery. Techniques range from dividing cases into intervals for metric comparison, to employing regression and cumulative summation (CUSUM) analyses. However, their inherent inconsistencies and methodological flaws limit their comparability and reliability. PURPOSE: To critically evaluate the methodologies used in existing literature for studying learning curves in spine surgery and to provide recommendations for future research. STUDY DESIGN: Systematic literature review. METHODS: A comprehensive literature search was conducted using PubMed, Embase, and Scopus databases, covering articles from January 2010 to September 2023. For inclusion, articles had to evaluate the change in a metric of performance during human spine surgery across time/a case series. Results had to be reported in sufficient detail to allow for evaluation of individual performance rather than group/institutional performance. Articles were excluded if they included cadaveric/nonhuman subjects, aggregated performance data or no way to infer change across a number of cases. Risk of bias was assessed using the Risk of Bias in Nonrandomized Studies of Interventions (ROBINS-I) tool. Surgical data were simulated using Python 3 and then examined via multiple commonly used analytic approaches including division into consecutive intervals, regression and CUSUM techniques. Results were qualitatively assessed to determine the effectiveness and limitations of each approach in depicting a learning curve. RESULTS: About 113 studies met inclusion criteria. The majority of the studies were retrospective and evaluated a single-surgeon's experience. Methods varied considerably, with 66 studies using a single proficiency metric and 47 using more than 1. Operating time was the most commonly used metric. Interval division was the simplest and most commonly used method yet inherent limitations prevent collective synthesis. Regression may accurately describe the learning curve but in practice is hampered by sample size and model choice. CUSUM analyses are of widely varying quality with some being fundamentally flawed and widely misinterpreted however, others provide a reliable view of the learning process. CONCLUSION: There is considerable variation in the quality of existing studies on learning curves in spine surgery. CUSUM analyses, when correctly applied, offer the most reliable estimates. To improve the validity and comparability of future studies, adherence to methodological guidelines is crucial. Multiple or composite performance metrics are necessary for a holistic understanding of the learning process.

Natural History of Intradiscal Vacuum Phenomenon and its Role in Advanced Disc Degeneration.

STUDY DESIGN: Observational serial computed tomography (CT) analysis of the lumbar spine in a normal-aging population. OBJECTIVE: To assess the natural history of the intradiscal vacuum phenomenon (IDVP) and its role in disc degeneration. BACKGROUND: The natural history of disc degeneration is well described but our understanding of the end stage of pathogenesis remains incomplete. Magnetic resonance imaging loses accuracy with advanced degeneration, becoming hyporesonant and indistinct. Cadaveric specimens display adaptive changes in the disc with loss of the hydrostatic capacity of the nucleus, increased intradiscal clefts, and endplate impermeability. IDVP is associated with advanced disc degeneration and CT is the optimal modality to visualize this, yet these insights remain unreported. PATIENTS AND METHODS: Patients only included historic CT abdomen scans of those over 60 years of age without acute or relevant spinal pathology, with a diagnosis of at least one level with IDVP on the original CT scan, and all of whom had a similar scan >7 years later. A history of clinically significant back pain was also recorded. RESULTS: CT scans included 360 levels in 29 males and 31 females (mean: 68.9 y), displaying 82 levels of IDVP, with a second scan included after a mean of 10.3 years. Most levels displayed the same level of severity (persisted, 45) compared with where some progressed (26), regressed (8), and fused (3; P < 0.01). There was also an increased incidence, 37/60 (62%) of developing IDVP at another level. Disc heights were reduced with increased severity of IDVP. A record of back pain was evident in 31/60 patients, which was not significantly worse in those with worsening severity or additional level involvement over the study period. CONCLUSION: As disc degeneration advances, the associated IDVP persists in most cases, displaying a plateauing of severity over long periods, but rarely with progression to autofusion.

The Environmental Impact of Spine Surgery and the Path to Sustainability.

STUDY DESIGN: Narrative literature review. OBJECTIVE: The aim of this study was to review published literature discussing sustainable health care and to identify aspects that pertain to spine surgery. SUMMARY OF BACKGROUND DATA: In recent years, research has investigated the contribution of surgical specialties to climate change. To our knowledge, no article has yet been published discussing the impact specific to spinal procedures and possible mitigation strategies. METHODS: A literature search was performed for the present study on relevant terms across four electronic databases. References of included studies were also investigated. RESULTS: Spine surgery has a growing environmental impact. Investigations of analogous specialties find that procurement is the single largest source of emissions. Carbon-conscious procurement strategies will be needed to mitigate this fully, but clinicians can best reduce their impact by adopting a minimalist approach when using surgical items. Reduced wastage of disposable goods and increased recycling are beneficial. Technology can aid remote access to clinicians, and also enable patient education. CONCLUSIONS: Spine-surgery-specific research is warranted to evaluate its carbon footprint. A broad range of measures is recommended from preventative medicine to preoperative, intraoperative, and postoperative spine care. LEVEL OF EVIDENCE: 5.