Stem Cells and Spinal Fusion

Efficacy of using autologous cells with graft substitutes for spinal fusion surgery: A systematic review and meta-analysis of clinical outcomes and imaging features

Over the past several decades, there has been a notable increase in the total number of spinal fusion procedures worldwide. Advanced spinal fusion techniques, surgical approaches, and new alternatives in grafting materials and implants, as well as autologous cellular therapies, have been widely employed for treating spinal diseases. While the potential of cellular therapies to yield better clinical results is appealing, supportive data are needed to confirm this claim. This meta-analysis aims to compare the radiographic and clinical outcomes between graft substitutes with autologous cell therapies and graft substitutes alone. PubMed, Scopus, Web of Science, ClinicalTrials.gov, and the Cochrane Central Register of Controlled Trials were searched for studies comparing graft substitutes with autologous cell therapies and graft substitutes alone up to February 2024. The risk of bias of the included studies was evaluated using the Downs and Black checklist. The following outcomes were extracted for comparison: fusion success, complications/adverse events, Visual Analog Scale (VAS) score, and Oswestry Disability Index (ODI) score. Thirteen studies involving 836 patients were included, with 7 studies considered for the meta-analysis. Results indicated that the use of graft substitutes with autologous cell therapies demonstrated higher fusion success rates at 3, 6, and 12 months, lower VAS score at 6 months, and lower ODI score at 3, 6, and 12 months. The complication rate was similar between graft substitutes with autologous cell therapies and graft substitutes alone. Although the current literature remains limited, this meta-analysis suggests that the incorporation of cellular therapies such as bone marrow and platelet derivatives with graft substitutes is associated with a higher fusion rate and significant improvements in functional status and pain following spinal fusion. Future well-designed randomized clinical trials are needed to definitively assess the clinical effectiveness of cellular therapies in spinal fusion.

Global Stem Cell Research in Orthopaedics: A Bibliometric Study from 1995 to 2020

Background

The research field of stem cell-based therapies in orthopaedics has witnessed significant growth in the recent past. We aimed to identify and analyze the bibliometric characteristics of the global highly cited papers (HCPs) in stem cell research in orthopaedics.

Methods

This study relied on secondary data extracted from Scopus, Elsevier's abstract and citation database. An advanced search string was employed, for the period from 1995 to 2020. For each paper, the extracted information included the number of citations, title, authors (name, number, authorship position, and country), year of publication, title of the journals, study design, and thematic field. The VOSviewer (1.6.20) was used to uncover relationships between authors, institutions, keywords, and publications.

Results

There were a total of 1427 publications and out of these 186 papers had 100 or more citations (range 100-2644) and were considered as HCPs. The average citation per paper (CPP) was 265.8. Only 4% of the top HCPs contributed 20% of the total citations of all HCPs. All the HCPs were published from high-income countries, and the USA was the leading country in all aspects of publication on stem cell research. Méndez-Ferrer S registered the highest citation (n = 2644), Prockop DJ was the most prolific author (n = 8 papers), and Harvard Medical School, USA emerged as the most prolific organization with 12 HCPs.

Conclusion

Global research in stem cell therapies for orthopaedic problems is making strides, and is an emerging field of research. Stem cell research offers the potential for improved treatment outcomes for various musculoskeletal conditions.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s43465-024-01160-0.

Diagnosis and Treatment of Skipped Multifocal Spinal Tuberculosis Lesions

Spinal tuberculosis, also known as Pott's disease or tuberculous spondylitis, is usually secondary to primary infection in the lungs or other systems, and in most instances, is thought to be transmitted via blood. Typical manifestations of infection include narrowing of the intervertebral disc by erosion and bone destruction of adjacent vertebrae. Atypical spinal tuberculosis is a specific type of spinal tuberculosis. It mainly consists of single vertebral lesions, single posterior structure lesions, multiple vertebral lesions, and intra-spinal lesions. Skipped multifocal spinal tuberculosis is one of these types and is characterized by two or more vertebral lesions without the involvement of the adjoining intervertebral discs, regardless of their location. To date, only a few cases have been reported. Upon clinical admission, it can be treated conservatively or surgically, depending on the patient's symptoms. In addition, gene or biological therapies are being investigated. However, because of the exceptional imaging findings and insidious symptoms, it is often misdiagnosed as a neoplastic lesion, osteoporotic fracture, or other infectious spondylitis, increasing the risk of neurological deficit and kyphotic deformity, and delaying the optimal treatment window. In this study, we review the diagnosis and treatment strategies for skipped multifocal spinal tuberculosis lesions and enumerate the common differential diagnoses, to provide reference and guidance for clinical treatment and diagnosis direction.

A Pre-clinical Standard Operating Procedure for Evaluating Orthobiologics in an In Vivo Rat Spinal Fusion Model

The rat animal model is a cost effective and reliable model used in spinal pre-clinical research. Complications from various surgical procedures in humans often arise that were based on these pre-clinical animal models. Therefore safe and efficacious pre-clinical animal models are needed to establish continuity into clinical trials. A Standard Operating Procedure (SOP) is a validated method that allows researchers to safely and carefully replicate previously successful surgical techniques. Thus, the aim of this study is to describe in detail the procedures involved in a common rat bilateral posterolateral intertransverse spinal fusion SOP used to test the efficacy and safety different orthobiologics using a collagen-soaked sponge as an orthobiologic carrier. Only two orthobiologics are currently FDA approved for spinal fusion surgery which include recombinant bone morphogenetic protein 2 (rhBMP-2), and I-FACTOR. While there are many additional orthobiologics currently being tested, one way to show their safety profile and gain FDA approval, is to use well established pre-clinical animal models. A preoperative, intraoperative, and postoperative surgical setup including specific anesthesia and euthanasia protocols are outlined. Furthermore, we describe different postoperative methods used to validate the spinal fusion SOP, which include μCT analysis, histopathology, biomechanical testing, and blood analysis. This SOP can help increase validity, transparency, efficacy, and reproducibly in future rat spinal fusion surgery procedures.