Spino-femoral muscles affect sagittal alignment and compensatory recruitment: a new look into soft tissues in adult spinal deformity

Objective To quantify muscle characteristics (volumes and fat infiltration) and identify their relationship to sagittal malalignment and compensatory mechanism recruitment. Methods Female adult spinal deformity patients underwent T1-weighted MRI with a 2-point Dixon protocol from the proximal tibia up to the T12 vertebra. 3D reconstructions of 17 muscles, including extensors and flexors of spine, hip and knee, were obtained. Muscle volume standardized by bone volume and percentage of fat infiltration (Pfat) were calculated. Correlations and regressions were performed. Results A total of 22 patients were included. Significant correlations were observed between sagittal alignment and muscle parameters. Fat infiltration of the hip and knee flexors and extensors correlated with larger C7-S1 SVA. Smaller spinal flexor/extensor volumes correlated with greater PI-LL mismatch (r = − 0.45 and − 0.51). Linear regression identified volume of biceps femoris as only predictor for PT (R2 = 0.34, p = 0.005) and Pfat of gluteus minimus as only predictor for SVA (R2 = 0.45, p = 0.001). Sagittally malaligned patients with larger PT (26.8° vs. 17.2°) had significantly smaller volume and larger Pfat of gluteus medius, gluteus minimus and biceps femoris, but similar values for gluteus maximus, the hip extensor. Conclusion This study is the first to quantify the relationship between degeneration of spino-femoral muscles and sagittal malalignment. This pathoanatomical study identifies the close relationship between gluteal, hamstring muscles and PT, SVA, which deepens our understanding of the underlying etiology that contributes to adult spinal deformity.The manuscript submitted does not contain information about medical device(s)/drug(s). This work received funding from Youth Fund of Natural Science Foundation of Jiangsu Province (BK20180122). This work received funding from Key Project supported by Medical Science and Technology Development Foundation, Nanjing Department of Health (YKK18092)

Three-dimensional reconstruction using stereoradiography for evaluating adult spinal deformity: a reproducibility study.

PURPOSE: In addition to the sagittal alignment, impact of transverse plane parameters (TPP) and rotatory subluxation on patients reported outcomes were highlighted. One of the hypotheses for genesis of degenerative scoliosis is disc degeneration with increased axial vertebral (AVR) and intervertebral rotation (AIR). Therefore, TPP analysis at early stage of the scoliosis seems of particular interest. This study aims at assessing reliability of tridimensional (3D) reconstructions of adult spinal deformity (ASD) patients. METHODS: Thirty ASD patients underwent biplanar radiographs and were divided into two groups (Cobb angle >30° or <30°). Spinal parameters and TPP (apical AVR, AIR of upper and lower level of main curve) were measured. Four operators performed 3D reconstructions twice. Intra and inter-observer reliabilities were analyzed using ISO standard 5725-2, to quantify the global standard deviation of reproducibility (S R). RESULTS: Mean Cobb angle was 31°, mean age 55 years (70% of female). Mean values of apical AVR, upper and lower level AIR were, respectively, 16° ± 15°, 6° ± 6° and 5° ± 5°. Spinopelvic parameters S R were below 4.5°. For Cobb angle <30°, S R was 7.8°, 9.6°, 4.5° and 4.9°, respectively, for AVR apex, torsion index, upper and lower AIR. Reliability was worse in the group of patients with Cobb angle above 30°. CONCLUSIONS: 3D analysis was reliable for Cobb and sagittal parameters. 3D analysis for TPP was reproducible when Cobb is below 30°. However, uncertainty is larger for Cobb above 30°. Nevertheless, 3D reconstructions could help surgeons to anticipate onset of rotatory subluxation while assessing axial rotation evolution for small deformity and choose best delay for surgical treatment

Surgeon’s Magic Wand: A Screen Pointing Interactive Method

Abstract: A novel, non-touch, screen pointing “magic wand ” interface is proposed for surgeon’s use in an environment requiring simultaneous display of several patients ’ data over a continuous period of time. The magic wand or passive pointing device does not have any active energy source within it (as opposed to a laser pointer) and thus cannot easily be detected or identified. Thus, modeling and simulation task is carried out by generating high resolution color images of a pointer viewing via two digital cameras with a popular three-dimensional (3D) computer graphics and animation program, Studio 3D Max by Discreet is used for detection. These images are then retrieved for analysis into a Microsoft’s Visual C ++ program developed based on the theory of image triangulation. The program outputs the precise coordinates of the surgeon’s wand in the 3D space along with its projection on a large view screen. The computational results of the pointer projection are compared to the known locations specified by the Studio 3D Max for different simulated configurations. High pointing accuracy is achieved: a pointer kept 30 feet away correctly hits the target location within a few inches. This preliminary work will lead to a complex development for interactive hand pointing gesture recognition system and its applicability to a large viewing display environment. Keywords: Surgeon’s wand, screen pointing interface, passive pointer, image processing, hand pointing gesture Advances in medical research and technology drive the future of medicine, holding the promise of earlier and more accurate diagnosis of disease as well as safer and more effective treatments. Access to information remains crucial for delivering the most advanced car

Patient-reported outcome metrics in total joint arthroplasty.

The Patient Protection and Affordable Care Act includes several provisions that focus on improving the delivery of health care in the United States. Reducing overall healthcare costs and improving the quality of care delivered are two overarching themes of the Patient Protection and Affordable Care Act. An evaluation of quality in total joint arthroplasty focuses on three main areas: complications, readmissions, and, more recently, patient-reported outcomes. Patient-reported outcomes allow surgeons and patients to objectively document pain relief and functional gain after total joint arthroplasty. Surgeons, groups, or hospitals that commit to the collection of patient-reported outcomes must consider which patient-reported outcomes to capture, the workflow and timing of postoperative patient-reported outcome collection, and how to minimize the burden of patient-reported outcome collection on both patients and surgeons

Concurrent Presence of Thoracolumbar Scoliosis and Chiari Malformation: Is Operative Risk Magnified?

Study Design Retrospective review of Kids’ Inpatient Database (KID). Purpose: Identify the risks and complications associated with surgery in adolescents diagnosed with Chiari and scoliosis. Overview of Literature Scoliosis is frequently associated with Chiari malformation (CM). More specifically, reports have been made about this association with CM type I in the absence of syrinx status. Methods: The KID was used to identify all pediatric inpatients with CM and scoliosis. The patients were stratified into three groups: those with concomitant CM and scoliosis (CMS group), those with only CM (CM group), and those with only scoliosis (Sc group). Multivariate logistic regressions were used to assess association between surgical characteristics and diagnosis with complication rate. Results: A total of 90,707 spine patients were identified (61.8% Sc, 37% CM, 1.2% CMS). Sc patients were older, had a higher invasiveness score, and higher Charlson comorbidity index (all p<0.001). CMS patients had significantly higher rates of surgical decompression (36.7%). Sc patients had significantly higher rates of fusions (35.3%) and osteotomies (1.2%, all p<0.001). Controlling for age and invasiveness, postoperative complications were significantly associated with spine fusion surgery for Sc patients (odds ratio [OR], 1.8; p<0.05). Specifically, posterior spinal fusion in the thoracolumbar region had a greater risk of complications (OR, 4.9) than an anterior approach (OR, 3.6; all p<0.001). CM patients had a significant risk of complications when an osteotomy was performed as part of their surgery (OR, 2.9) and if a spinal fusion was concurrently performed (OR, 1.8; all p<0.05). Patients in the CMS cohort were significantly likely to develop postoperative complications if they underwent a spinal fusion from both anterior (OR, 2.5) and posterior approach (OR, 2.7; all p<0.001). Conclusions: Having concurrent scoliosis and CM increases operative risk for fusion surgeries despite approach. Being independently inflicted with scoliosis or Chiari leads to increased complication rate when paired with thoracolumbar fusion and osteotomies; respectively

Supplemental Material, Appendix_A - Adverse Outcomes and Prediction of Cardiopulmonary Complications in Elective Spine Surgery

<p> Supplemental Material, Appendix_A for Adverse Outcomes and Prediction of Cardiopulmonary Complications in Elective Spine Surgery by Peter G. Passias, Gregory W. Poorman, Edward Delsole, Peter L. Zhou, Samantha R. Horn, Cyrus M. Jalai, Shaleen Vira, Bassel Diebo, and Virginie Lafage in Global Spine Journal </p

Identifying Subsets of Patients With Adult Spinal Deformity Who Maintained a Positive Response to Nonoperative Management.

BACKGROUND: Adult spinal deformity (ASD) represents a major cause of disability in the elderly population in the United States. Surgical intervention has been shown to reduce disability and pain in properly indicated patients. However, there is a small subset of patients in whom nonoperative treatment is also able to durably maintain or improve symptoms. OBJECTIVE: To examine the factors associated with successful nonoperative management in patients with ASD. METHODS: We retrospectively evaluated a cohort of 207 patients with nonoperative ASD, stratified into 3 groups: (1) success, (2) no change, and (3) failure. Success was defined as a gain in minimal clinically importance difference in both Oswestry Disability Index and Scoliosis Research Society-Pain. Logistic regression model and conditional inference decision trees established cutoffs for success according to baseline (BL) frailty and sagittal vertical axis. RESULTS: In our cohort, 44.9% of patients experienced successful nonoperative treatment, 22.7% exhibited no change, and 32.4% failed. Successful nonoperative patients at BL were significantly younger, had a lower body mass index, decreased Charlson Comorbidity Index, lower frailty scores, lower rates of hypertension, obesity, depression, and neurological dysfunction (all P &lt; .05) and significantly higher rates of grade 0 deformity for all Schwab modifiers (all P &lt; .05). Conditional inference decision tree analysis determined that patients with a BL ASD-frailty index ≤ 1.579 (odds ratio: 8.3 [4.0-17.5], P &lt; .001) were significantly more likely to achieve nonoperative success. CONCLUSION: Success of nonoperative treatment was more frequent among younger patients and those with less severe deformity and frailty at BL, with BL frailty the most important determinant factor. The factors presented here may be useful in informing preoperative discussion and clinical decision-making regarding treatment strategies