Michael Grevitt

Pathogenesis of adolescent idiopathic scoliosis in girls - a double neuro-osseous theory involving disharmony between two nervous systems, somatic and autonomic expressed in the spine and trunk: possible dependency on sympathetic nervous system and hormones with implications for medical therapy

Anthropometric data from three groups of adolescent girls - preoperative adolescent idiopathic scoliosis (AIS), screened for scoliosis and normals were analysed by comparing skeletal data between higher and lower body mass index subsets. Unexpected findings for each of skeletal maturation, asymmetries and overgrowth are not explained by prevailing theories of AIS pathogenesis. A speculative pathogenetic theory for girls is formulated after surveying evidence including: (1) the thoracospinal concept for right thoracic AIS in girls; (2) the new neuroskeletal biology relating the sympathetic nervous system to bone formation/resorption and bone growth; (3) white adipose tissue storing triglycerides and the adiposity hormone leptin which functions as satiety hormone and sentinel of energy balance to the hypothalamus for long-term adiposity; and (4) central leptin resistance in obesity and possibly in healthy females. The new theory states that AIS in girls results from developmental disharmony expressed in spine and trunk between autonomic and somatic nervous systems. The autonomic component of this double neuro-osseous theory for AIS pathogenesis in girls involves selectively increased sensitivity of the hypothalamus to circulating leptin (genetically-determined up-regulation possibly involving inhibitory or sensitizing intracellular molecules, such as SOC3, PTP-1B and SH2B1 respectively), with asymmetry as an adverse response (hormesis); this asymmetry is routed bilaterally via the sympathetic nervous system to the growing axial skeleton where it may initiate the scoliosis deformity (leptin-hypothalamic-sympathetic nervous system concept = LHS concept). In some younger preoperative AIS girls, the hypothalamic up-regulation to circulating leptin also involves the somatotropic (growth hormone/IGF) axis which exaggerates the sympathetically-induced asymmetric skeletal effects and contributes to curve progression, a concept with therapeutic implications. In the somatic nervous system, dysfunction of a postural mechanism involving the CNS body schema fails to control, or may induce, the spinal deformity of AIS in girls (escalator concept). Biomechanical factors affecting ribs and/or vertebrae and spinal cord during growth may localize AIS to the thoracic spine and contribute to sagittal spinal shape alterations. The developmental disharmony in spine and trunk is compounded by any osteopenia, biomechanical spinal growth modulation, disc degeneration and platelet calmodulin dysfunction. Methods for testing the theory are outlined. Implications are discussed for neuroendocrine dysfunctions, osteopontin, sympathoactivation, medical therapy, Rett and Prader-Willi syndromes, infantile idiopathic scoliosis, and human evolution. AIS pathogenesis in girls is predicated on two putative normal mechanisms involved in trunk growth, each acquired in evolution and unique to humans.

Anterior thoracoscopic surgery followed by posterior instrumentation and fusion in spinal deformity.

Abstract Many authors believe thoracoscopic surgery is associated with a lower level of morbidity compared to thoracotomy, for anterior release or growth arrest in spinal deformity. Others believe that anterior release achieved thoracoscopically is not as effective as that achieved with the open procedure. We evaluated the clinical results, radiological correction and morbidity following anterior thoracoscopic surgery followed by posterior instrumentation and fusion, to see whether there is any evidence for either of these beliefs. Twenty-nine patients undergoing thoracoscopic anterior release or growth arrest followed by posterior fusion and instrumentation were evaluated from a clinical and radiological viewpoint. The mean follow-up was 2 years (range 1–4 years). The average age was 16 years (range 5–26 years). The following diagnoses were present: idiopathic scoliosis (n = 17), neuromuscular scoliosis (n = 2), congenital scoliosis (n = 1), thoracic hyperkyphosis (n = 9). All patients were satisfied with cosmesis following surgery. Twenty scoliosis patients had a mean preoperative Cobb angle of 65.1° (range 42°–94°) for the major curve, with an average flexibility of 34.5% (42.7°). Post operative correction to 31.5° (50.9%) and 34.4° (47.1%) at maximal follow-up was noted. For nine patients with thoracic hyperkyphosis, the Cobb angle averaged 81° (range 65°–96°), with hyperextension films showing an average correction to 65°. Postoperative correction to an average of 58.6° was maintained at 59.5° at maximal follow-up. The average number of released levels was 5.1 (range 3–7) and the average duration of the thoracoscopic procedure was 188 min (range 120–280 min). There was a decrease in this length of time as the series progressed. No neurologic or vascular complications occurred. Postoperative complications included four recurrent pneumothoraces, one surgical emphysema, and one respiratory infection. Thoracoscopic anterior surgery appears a safe and effective technique for the treatment of paediatric and adolescent spinal deformity. A randomised controlled trial, comparing open with thoracoscopic methods, is required.

The Global Spine Care Initiative: model of care and implementation

PurposeSpine-related disorders are a leading cause of global disability and are a burden on society and to public health. Currently, there is no comprehensive, evidence-based model of care for spine-related disorders, which includes back and neck pain, deformity, spine injury, neurological conditions, spinal diseases, and pathology, that could be applied in global health care settings. The purposes of this paper are to propose: (1) principles to transform the delivery of spine care; (2) an evidence-based model that could be applied globally; and (3) implementation suggestions.MethodsThe Global Spine Care Initiative (GSCI) meetings and literature reviews were synthesized into a seed document and distributed to spine care experts. After three rounds of a modified Delphi process, all participants reached consensus on the final model of care and implementation steps.ResultsSixty-six experts representing 24 countries participated. The GSCI model of care has eight core principles: person-centered, people-centered, biopsychosocial, proactive, evidence-based, integrative, collaborative, and self-sustaining. The model of care includes a classification system and care pathway, levels of care, and a focus on the patient’s journey. The six steps for implementation are initiation and preparation; assessment of the current situation; planning and designing solutions; implementation; assessment and evaluation of program; and sustain program and scale up.ConclusionThe GSCI proposes an evidence-based, practical, sustainable, and scalable model of care representing eight core principles with a six-step implementation plan. The aim of this model is to help transform spine care globally, especially in low- and middle-income countries and underserved communities.Graphical abstractThese slides can be retrieved under Electronic Supplementary Material.

The Global Spine Care Initiative: methodology, contributors, and disclosures

AbstractPurposeThe purpose of this report is to describe the Global Spine Care Initiative (GSCI) contributors, disclosures, and methods for reporting transparency on the development of the recommendations.nMethodsWorld Spine Care convened the GSCI to develop an evidence-based, practical, and sustainable healthcare model for spinal care. The initiative aims to improve the management, prevention, and public health for spine-related disorders worldwide; thus, global representation was essential. A series of meetings established the initiative’s mission and goals. Electronic surveys collected contributorship and demographic information, and experiences with spinal conditions to better understand perceptions and potential biases that were contributing to the model of care.nResultsSixty-eight clinicians and scientists participated in the deliberations and are authors of one or more of the GSCI articles. Of these experts, 57 reported providing spine care in 34 countries, (i.e., low-, middle-, and high-income countries, as well as underserved communities in high-income countries.) The majority reported personally experiencing or having a close family member with one or more spinal concerns including: spine-related trauma or injury, spinal problems that required emergency or surgical intervention, spinal pain referred from non-spine sources, spinal deformity, spinal pathology or disease, neurological problems, and/or mild, moderate, or severe back or neck pain. There were no substantial reported conflicts of interest.ConclusionThe GSCI participants have broad professional experience and wide international distribution with no discipline dominating the deliberations. The GSCI believes this set of papers has the potential to inform and improve spine care globally.Graphical abstractThese slides can be retrieved under Electronic Supplementary Material.

The Global Spine Care Initiative: World Spine Care executive summary on reducing spine-related disability in low- and middle-income communities

PurposeSpinal disorders, including back and neck pain, are major causes of disability, economic hardship, and morbidity, especially in underserved communities and low- and middle-income countries. Currently, there is no model of care to address this issue. This paper provides an overview of the papers from the Global Spine Care Initiative (GSCI), which was convened to develop an evidence-based, practical, and sustainable, spinal healthcare model for communities around the world with various levels of resources.MethodsLeading spine clinicians and scientists around the world were invited to participate. The interprofessional, international team consisted of 68 members from 24 countries, representing most disciplines that study or care for patients with spinal symptoms, including family physicians, spine surgeons, rheumatologists, chiropractors, physical therapists, epidemiologists, research methodologists, and other stakeholders.ResultsLiterature reviews on the burden of spinal disorders and six categories of evidence-based interventions for spinal disorders (assessment, public health, psychosocial, noninvasive, invasive, and the management of osteoporosis) were completed. In addition, participants developed a stratification system for surgical intervention, a classification system for spinal disorders, an evidence-based care pathway, and lists of resources and recommendations to implement the GSCI model of care.ConclusionThe GSCI proposes an evidence-based model that is consistent with recent calls for action to reduce the global burden of spinal disorders. The model requires testing to determine feasibility. If it proves to be implementable, this model holds great promise to reduce the tremendous global burden of spinal disorders.Graphical abstractThese slides can be retrieved under Electronic Supplementary Material.

Preservation of Spine Motion in the Surgical Treatment of Adolescent Idiopathic Scoliosis Using an Innovative Apical Fusion Technique: A 2-Year Follow-Up Pilot Study

ABSTRACT Background: This trial reports the 2-year and immediate postremoval clinical outcomes of a novel posterior apical short-segment (PASS) correction technique allowing for correction and stabilization of adolescent idiopathic scoliosis (AIS) with limited fusion. Methods: Twenty-one consecutive female AIS patients were treated at 4 institutions with this novel technique. Arthrodesis was limited to the short apical curve after correction with translational and derotational forces applied to upper and lower instrumented levels. Instrumentation spanned fused and unfused segments with motion and flexibility of unfused segments maintained. The long concave rods were removed at maturity. Radiographic data collected included preoperative and postoperative data for up to 2 years as well as after long rod removal. Results: All 21 patients are beyond 2 years postsurgery. Average age at surgery was 14.2 years (11–17 years). A mean of 10.5 ± 1 levels per patient were stabilized and 5.0 ± 0.5 levels (48%) were fused. Cobb angle improved from 56.1° ± 8.0° to 20.8° ± 7.8° (62.2% improvement) at 1 year and 20.9° ± 8.4°, (62.0% improvement) at 2 years postsurgery. In levels instrumented but not fused, motion was 26° ± 6° preoperatively compared to 10° ± 4° at 1 year postsurgery, demonstrating 38% maintenance of mobility in nonfused segments. There was no report of implant-related complications. Conclusions: PASS correction technique corrected the deformity profile in AIS patients with a lower implant density while sparing 52% of the instrumented levels from fusion through the 2-year follow-up.

A Cost-Effectiveness Analysis of Intradiscal Electrothermal Therapy (IDET) Compared with Circumferential Lumbar Fusion

Cost‐effectiveness analysis.

Expert’s comment concerning Grand Rounds case entitled “Fusionless posterior hemivertebra resection in a 2-year-old child with 16 years follow-up” (by D. Jeszenszky, T. F. Fekete, F. S. Kleinstueck, D. Haschtmann, L. Bognár)

The authors [1] are to be congratulated on this novel and iconoclastic approach to a congenital hemivertebra (HV). The case is further enhanced by the necessary long-term follow-up demonstrating no late deformity. Before judging this technique’s overall worth and where it fits in the surgeon’s armamentarium in dealing with these potentially difficult congenital problems (especially if presenting late or neglected), it is necessary to compare previous studies. Marks et al. [2] published the results of the late Harry Piggott’s experience of convex epiphysiodesis for HV. The message from that paper was that the technique was successful in controlling deformity (but not correcting it) provided the surgical intervention was early and the arthrodesis extended over several segments. Harms [3, 4] popularised HV resection and his data confirm that a more limited fusion satisfactorily maintains the correction achieved (validating the Hueter–Volkmann Law). However, notwithstanding considerable surgical virtuosity, there was a 10% rate of technical problems and similar rate of late deformity. A multicentre comparison [5] of convex epiphysiodesis with hemivertebra excision confirmed that the excision gave better radiological results but at the cost of a higher complication rate (44%). This surgical solution seems to have significant advantages over the above-immediate correction of the scoliotic deformity, avoiding a potentially long arthrodesis and possibly preserving a motion segment. However, the reader should understand that there are specific indications that limit its application. These include:

7:52 Surgical correction of sagittal deformity in Scheuermann kyphosis

Purpose of study: Surgically treated Scheuermann kyphosis cases have been reviewed to evaluate the factors affecting the degree of correction, loss of correction and proximal and distal junctional kyphosis. n nMethods used: Thirty-nine cases (24 male, 15 female) of Scheuermann kyphosis, treated surgically to relieve persistent pain or progressive deformity, during 1992 to 1999, were reviewed. Median age at operation was 18 years (14 to 53 years). Mean preoperative kyphosis (Cobb angle) was 81uf0b0 (65uf0b0-115uf0b0). The apex of the curve was at T8 or higher in 20 cases and at T9 or lower in 19 cases. Flexible curves, which bend down to below 45uf0b0 on hyperextension bending X-ray (n=12) had one-stage posterior surgery only, using segmental instrumentation. Rigid curves (greater than 45uf0b0 on bending films) had either thoracoscopic anterior release (n=17) or open anterior release (n=10), followed by antero-posterior (AP) instrumentation. n nof findings: Mean follow-up was 45 months (26 to 140 months). The mean direct postoperative kyphosis was 47.2 degrees (38 to 75 degrees), and mean loss of correction at final follow-up was 9.3 degrees (0 to 17 degrees). Kyphosis correction achieved at final follow-up ranged from 39% after posterior-only surgery, to 42% after thoracoscopic AP surgery and 48% after open AP surgery. Mean loss of correction was 12 degrees after posterior-only surgery, 9.5 degrees after thoracoscopic AP surgery and 6 degrees after open AP surgery. Four cases of open AP surgery had additional anterior structural support with cages, before posterior instrumentation. A mean 55% kyphosis correction was achieved in this group, and there was no loss of correction. Younger cases, under 18 years (n=21) had significantly better kyphosis correction than the older age group (p<.05). Four cases (10%) developed distal junctional kyphosis resulting from fusion short of the first lordotic segment. All of them had the apex below T9. Six cases (15%) developed proximal junctional kyphosis; all of them had the apex above T6. Complications included infection (four), pneumothorax (one), heamothorax (one), instrumentation failure (four cases); three cases had persistent back pain. n nRelationship between findings and existing knowledge: No correlation between the four different types of curves described in the literature (upper, middle, lower and whole thoracic) and the outcome was found in this study. n nOverall significance of findings: Combined anterior release and posterior surgery achieves and maintains better correction of Scheuermann kyphosis. Anterior structural support prevents loss of correction. Proximal junctional kyphosis is more common in higher curves, and distal junctional kyphosis is more common in lower curves. Correction is better achieved in younger patients but is not influenced by the location of the curve. n nDisclosures: Device or drug: pedicle screws and rods. Status: approved. n nConflict of interest: No conflicts.