Paraspinal musculature impairment is associated with spinopelvic and spinal malalignment in patients undergoing lumbar fusion surgery

BACKGROUND CONTEXTThe 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.PURPOSEThis study aimed to investigate the influence of the posterior paraspinal muscles (PPM, erector spinae, and multifidus) and the psoas muscle on spinopelvic and spinal alignment.STUDY DESIGN/SETTINGRetrospective cross-sectional study.PATIENT SAMPLEPatients undergoing posterior lumbar fusion between 2014 and 2021 for degenerative conditions at a tertiary care center, with preoperative lumbar magnetic resonance imaging (MRI) within 12 months prior the surgery and a preoperative whole spine radiograph were included.OUTCOME MEASURESPPM and psoas muscle measurements including the cross-sectional area (CSA), the functional cross-sectional area (fCSA), the amount of intramuscular fat (FAT), and the percentage of fat infiltration (FI). Spinopelvic measurements including lumbar lordosis (LL), pelvic tilt (PT), sacral slope (SS), pelvic incidence (PI), and sagittal vertical axis (SVA).METHODSA T2-weighted MRI-based quantitative assessment of the CSA, the fCSA and the amount FAT was conducted, and FI was further calculated. The regions of interest included the psoas muscle and the PPM on both sides at the L4 level that were summarized and normalized by the patient's height (cm²/m²). LL, PT, SS, PI, and SVA were determined on standing lateral radiographs. Spearman correlation was used to calculate the crude relationship between spinopelvic and muscle parameters. Multiple linear regression models with age, sex, LL, PT, SS, and SVA set as independent variables were established to determine the association with spinal muscle outcome measures.RESULTSA total of 150 patients (53.3% female) were included in the final analysis with a median age of 65.6 years and a median BMI of 28.2 kg/m². Significant positive correlations were observed between PT (ρ=0.327), SVA (ρ=0.256) and PI (ρ=0.202) and the FI_PPM. Significant negative correlations were detected for the PT and the fCSA_PPM (ρ=-0.202) and PT and the fCSA_Psoas (ρ=-0.191). Furthermore, a negative correlation was seen for PI and SVA and FI_Psoas. PT (β=0.187; p=.006), SVA (β=0.155; p=.035), age (β=0.468; p<.001) and sex (β=0.235; p<.001) significantly predict FI_PPM (corrected R²=0.393) as independent variables.CONCLUSIONSThis study demonstrated the potential role of posterior paraspinal muscles and psoas muscle on pelvic retroversion and elucidated the relation to sagittal spinal malalignment. Although we cannot establish causality, we propose that increasing FI_PPM, representing loss of muscular strength, may lead to increased pelvic retroversion and thus might be the initiating point for the development of the sagittal imbalance. These findings might challenge the well-known theory of increased pelvic retroversion being a compensatory mechanism for sagittal spinal balance. Thus, muscular weakness might be a factor involved in the development of sagittal spinal malalignment.     

Clinical outcomes and fusion success associated with the use of BoneSave in spinal surgery

Background  

Achieving spinal fusion is the guiding principle behind surgical treatment for a range of spinal pathologies, often requiring a substantial amount of bonegraft. Iliac crest autograft represents the gold standard although associated morbidities and limited graft material have led to the development of alternatives. BoneSave (Stryker, UK), a porous tricalcium phosphate-hydroxyapatite ceramic, is one such alternative, employed in spinal fusion over the past few years. Very little research exists into the clinical outcomes associated with its use.     

Assessment of hospital quality and safety standards among Medicare beneficiaries undergoing surgery for cancer

BackgroundWe sought to assess the relationship between Leapfrog minimum volume standards, Hospital Safety Grades, and Magnet recognition with outcomes among patients undergoing rectal, lung, esophageal, and pancreatic resection for cancer.MethodsStandard Analytical Files linked with the Leapfrog Hospital Survey and the Leapfrog Safety Scores Denominator Files were used to identify Medicare patients who underwent surgery for cancer from 2016 to 2017. Multivariable logistic regression analysis was used to examine textbook outcomes relative to Leapfrog volume, safety grades, and Magnet recognition.ResultsAmong 26,268 Medicare beneficiaries, 7,491 (28.5%) were treated at hospitals meeting the quality trifactor (Leapfrog, safety grade A, and Magnet recognition) vs 18,777 (71.5%) at hospitals not meeting ≥1 designation. Patients at trifactor hospitals had lower odds of complications (odds ratio = 0.83, 95% confidence interval: 0.76–0.89), prolonged duration of stay (odds ratio = 0.89, 95% confidence interval: 0.82–0.97), and higher odds of experiencing textbook outcome (odds ratio = 1.12, 95% confidence interval: 1.06–1.19). Patients undergoing surgery for lung (odds ratio = 1.19, 95% confidence interval: 1.10–1.30) and pancreatic cancer (odds ratio = 1.37, 95% confidence interval: 1.21–1.55) at trifactor hospitals had higher odds of textbook outcome, whereas this effect was not noted after esophageal (odds ratio = 1.16, 95% confidence interval: 0.90–1.48) or rectal cancer (odds ratio = 1.11, 95% confidence interval: 0.98–1.27) surgery. Leapfrog minimum volume standards mediated the effect of the quality trifactor on patient outcomes.ConclusionQuality trifactor hospitals had better short-term outcomes after lung and pancreatic cancer surgery compared with nontrifactor hospitals.     

Transient loss of motor-evoked responses associated with caudal injection of morphine in a patient with spondylolisthesis undergoing spinal fusion

A 7-year-old girl having posterior spinal fusion for Grade 3 anterior spondylolisthesis at the L5/S1 level was administered 2.5 mg of morphine in 10 ml saline via the caudal epidural route before surgery. Motor-evoked responses were markedly diminished in her lower limbs for 1 h following this but returned spontaneously. She suffered no neurological injury. The cause for this is postulated to be transient cauda equina compression from the volume of injectate. This complication of caudal injection has not been reported before. The possible mechanisms for this are discussed. We believe that significant L5/S1 spondylolisthesis should be considered a contraindication to the use of caudal epidural injections.     

Anaesthetic considerations in patients with muscular dystrophy undergoing spinal fusion and harrington rod insertion

Charts of nine patients with Duchenne and one with Becker’s muscular dystrophy who had undergone spinal fusion and Harrington rod insertion for scoliosis were reviewed retrospectively. The mean age was 15 years and mean angle of scoliosis was 69 degrees. Preoperative pulmonary function studies showed a restrictive defect with a mean vital capacity of 1.3 ± 0.69 litres, 35 ± 20 per cent of predicted value, 33 ± 20 ml-kg^-1 and a mean inspiratory capacity of 0.99 ±0.5 litres, 23 ± 13 ml.kg^-1. There were no anaesthetic complications during operation and obstructive cardiomyopathy, hyperpyrexia, hyperkalaemia and rhabdomyolysis were not problems. Succinylcholine was avoided. One patient developed an arrhythmia postoperatively and one patient whose postoperative problems included tracheostomy, pneumonia and sepsis could not be weaned from the ventilator and died 11 weeks after operation. As assessing risk and survival of the operation depends on objective pulmonary function, a vital capacity of at least 20 ml-kg^-1 in the range of 30 per cent of predicted volume with an inspiratory capacity of at least 15 ml.kg^-1 would appear to be adequate in patients with muscular dystrophy requiring Harrington rod insertion. Other factors including the rapidity of progression of the muscular disease, other respiratory and cardiovascular problems, and disease such as obesity should also be considered.     

Long-term health care utilisation and costs after spinal fusion in elderly patients

Purpose

Spinal fusion surgery rates in the elderly are increasing. Cost effectiveness analyses with relatively short-length follow-up have been performed. But the long-term effects in terms of health care use are largely unknown. The aim of the present study was to describe the long-term consequences of spinal fusion surgery in elderly patients on health care use and costs using a health care system perspective.

Methods

194 patients undergoing spinal fusion between 2001 and 2005 (70 men, 124 women) with a mean age of 70 years (range 59–88) at surgery were included. Average length of follow-up was 6.2 years (range 0.3–9.0 years). Data on resource utilisation and costs were obtained from national registers providing complete coverage of all reimbursed contacts with primary- and secondary health care providers. Data were available from 3 years prior fusion surgery until the end of 2009.

Results

Use of hospital-based health care increased in the year prior to and the first year following surgery. Hereafter it normalised to the level of the background population and was mainly composed of diseases unrelated to the spine. In contrast, the use of primary health care appeared to increase immediately after surgery and continued to increase to a level that significantly exceeded that of the background population. It could be demonstrated that the increase was mainly due to an increasing number of general practitioner consultations.

Conclusion

Spinal fusion surgery in older patients does not generate excess hospital-based health care use in the longer term as compared with the background population, but primary care use increases.     

无创血红蛋白监测在脊柱融合术中的应用研究

目的探讨无创血红蛋白浓度(SpHb)监测与动脉血气分析血红蛋白浓度(Thbc)监测在脊柱融合术中的准确性及影响因素,旨在明确SpHb监测能否用于指导术中输血。方法全麻下行择期脊柱融合术的成年患者53例,ASAⅠ~Ⅲ级。于切皮前、植骨融合、手术结束和出血量每超过400ml即刻,记录SpHb、Thbc、静脉血常规血红蛋白浓度、手术时间、术中出血量、末梢灌注指数(PI)、MAP、CVP、体温、输注液体种类及总量。结果用一致性检验、回归分析和非参数检验进行统计分析。结果 SpHb与血红蛋白浓度的一致性弱于Thbc与血红蛋白浓度的一致性;SpHb与血红蛋白浓度成正相关(r=0.77,P0.01),Thbc与血红蛋白浓度成正相关(r=0.89,P0.01);SpHb与血红蛋白浓度、Thbc与血红蛋白浓度差值的平均值分布差异有统计学意义(P0.01)。出血量、输注胶体、PI对SpHb监测的准确性有影响(P0.05)。结论 SpHb监测总体上能反映体内血红蛋白浓度的变化趋势,可为临床有创测定血红蛋白浓度的采血时机提供参考。其准确性受众多因素影响,其在指导术中输血中的应用宜与动脉血气分析或静脉血常规测定相结合。     

Incidence and mortality of acute renal failure in Medicare beneficiaries, 1992 to 2001

This study's objective was to determine the incidence and mortality of acute renal failure (ARF) in Medicare beneficiaries. Data were from hospitalized Medicare beneficiaries (5,403,015 discharges) between 1992 and 2001 from the 5% sample of Medicare claims. For 1992 to 2001, the overall incidence rate of ARF was 23.8 cases per 1000 discharges, with rates increasing by approximately 11% per year. Older age, male gender, and black race were strongly associated (P < 0.0001) with ARF. The overall in-hospital death rate was 4.6% in discharges without ARF, 15.2% in discharges with ARF coded as the principal diagnosis, and 32.6% in discharges with ARF as a secondary diagnosis. In-hospital death rates were 32.9% in discharges with ARF that required renal dialysis and 27.5% in those with ARF that did not require dialysis. Death within 90 d after hospital admission was 13.1% in discharges without ARF, 34.5% in discharges with ARF coded as the principal diagnosis, and 48.6% in discharges with ARF as a secondary diagnosis. Discharges with ARF were more (P < 0.0001) likely to have intensive care and other acute organ dysfunction than those without ARF. For discharges both with and without ARF, rates for death within 90 d after hospital admission showed a declining trend. In conclusion, the incidence rate of ARF in Medicare beneficiaries has been increasing. Those of older age, male gender, and black race are more likely to have ARF. These data show ARF to be a major contributor to morbidity and mortality in hospitalized patients.     

Trends of spinal fusion surgery in Australia: 1997 to 2006

Background: This study aims to explore the trend in spine fusion surgery in Australia over the past 10 years, and to explore the possible influence of health insurance status (private versus public) on the rate of surgery. Methods: Data pertaining to the rate of lumbar spine fusion from 1997 to 2006 were collected from Inpatient Statistics Collection of NSW Health, Medicare Australia Statistics and the Australian Bureau of Statistics. Data on total hip and total knee arthroplasties were collected to provide a comparator. Results: The number of publicly performed spinal fusion procedures increased by 2% from 1997 to 2006. In comparison, privately performed spinal fusion procedures increased by 167% over the same 10‐year period. In 2006, spine fusion surgery was 10.8 times more likely to be done in the private sector than in the public sector, compared with corresponding figures of 4.2 times and 3.0 times for knee replacement and hip replacement, respectively. Waiting list data showed no increase in demand for spine fusion surgery in the public sector. Conclusion: There is a disproportionately high rate of lumbar spine fusion surgery performed in the private sector, given the rate of private insurance. The rate of increase was found to be higher than that for hip or knee arthroplasty procedures. Possible explanations for this difference include: over‐servicing in the private sector, under‐servicing in the public sector, differences in medical referral patterns, surgeon and patient preferences and financial incentives.