Clinical outcomes, MRI evaluation and predictive factors of indirect decompression with lateral transpsoas approach for lumbar interbody fusion: a multicenter experience.

Introduction: Evaluating the effects of indirect decompression obtained through lateral lumbar interbody fusion (LLIF) by clinical improvements and radiological parameters on MRI scans. Identifying predictors of better decompression and clinical outcome. Materials and methods: From 2016 to 2019, patients who underwent single- or double-level indirect decompression LLIF were consecutively reviewed. Radiological signs of indirect decompression were evaluated in preoperative and follow-up MRI studies and were subsequently correlated to clinical data, expressed as axial/radicular pain (VAS back/leg), index of disability (Oswestry Disability Index) and clinical severity of lumbar stenosis (Swiss Spinal Stenosis Questionnaire). Results: 72 patients were enrolled. The mean follow-up was 24 months. Differences in vertebral canal area (p < 0.001), height of the foramina (p < 0.001), thickness of the yellow ligament (p = 0.001) and anterior height of the interbody space (p = 0.02) were observed. Older age (p = 0.042), presence of spondylolisthesis (p = 0.042), presence of intra-articular facet effusion (p = 0.003) and posterior height of the implanted cage (p = 0.020) positively affected the increase of the canal area. Change in root canal area (p < 0.001), height of the implanted cage (p = 0.020) and younger age (p = 0.035) were predictive factors of root pain relief, while increased vertebral canal area (p = 0.020) and height of the interbody fusion cage (p = 0.023) positively affected the severity of clinical stenosis. Conclusions: LLIF indirect decompression showed both clinical and radiological improvements. Presence and degree of spondylolisthesis, presence of intra-articular facet effusion, age of the patient and height of the cage were predictive factors of major clinical improvements.

Relationship between lumbar lordosis, pelvic parameters, PI-LL mismatch and outcome after short fusion surgery for lumbar degenerative disease. Literature review, rational and presentation of public study protocol: RELApSE study (registry for evaluation of lumbar artrodesis sagittal alignEment).

Background: Vertebral arthrodesis for degenerative pathology of the lumbar spine still remains burdened by clinical problems with significant negative results. The introduction of the sagittal balance assessment with the evaluation of the meaning of pelvic parameters and spinopelvic (PI-LL) mismatch offered new evaluation criteria for this widespread pathology, but there is a lack of consistent evidence on long-term outcome. Methods: The authors performed an extensive systematic review of literature, with the aim to identify all potentially relevant studies about the role and usefulness of the restoration or the assessment of Sagittal balance in lumbar degenerative disease. They present the study protocol RELApSE (NCT05448092 ID) and discuss the rationale through a comprehensive literature review. Results: From the 237 papers on this topic, a total of 176 articles were selected in this review. The analysis of these literature data shows sparse and variable evidence. There are no observations or guidelines about the value of lordosis restoration or PI-LL mismatch. Most of the works in the literature are retrospective, monocentric, based on small populations, and often address the topic evaluation partially. Conclusions: The RELApSE study is based on the possibility of comparing a heterogeneous population by pathology and different surgical technical options on some homogeneous clinical and anatomic-radiological measures aiming to understanding the value that global lumbar and segmental lordosis, distribution of lordosis, pelvic tilt, and PI-LL mismatch may have on clinical outcome in lumbar degenerative pathology and on the occurrence of adjacent segment disease.

Obesity and Spine Surgery: A Qualitative Review About Outcomes and Complications. Is It Time for New Perspectives on Future Researches?

STUDY DESIGN: Literature review. OBJECTIVES: An increasing number of obese patients requires operative care for degenerative spinal disorders. The aim of this review is to analyze the available evidence regarding the role of obesity on outcomes after spine surgery. Peri-operative complications and clinical results are evaluated for both cervical and lumbar surgery. Furthermore, the contribution of MIS techniques for lumbar surgery to play a role in reducing risks has been analyzed. METHODS: Only articles published in English in the last 10 years were reviewed. Inclusion criteria of the references were based on the scope of this review, according to PRISMA guidelines. Moreover, only paper analyzing obesity-related complications in spine surgery have been selected and thoroughly reviewed. Each article was classified according to its rating of evidence using the Sacket Grading System. RESULTS: A total number of 1636 articles were found, but only 130 of them were considered to be relevant after thorough evaluation and according to PRISMA checklist. The majority of the included papers were classified according to the Sacket Grading System as Level 2 (Retrospective Studies). CONCLUSION: Evidence suggest that obese patients could benefit from spine surgery and outcomes be satisfactory. A higher rate of peri-operative complications is reported among obese patients, especially in posterior approaches. The use of MIS techniques plays a key role in order to reduce surgical risks. Further studies should evaluate the role of multidisciplinary counseling between spine surgeons, nutritionists and bariatric surgeons, in order to plan proper weight loss before elective spine surgery.

Augmented Reality in Medical Practice: From Spine Surgery to Remote Assistance.

Background: While performing surgeries in the OR, surgeons and assistants often need to access several information regarding surgical planning and/or procedures related to the surgery itself, or the accessory equipment to perform certain operations. The accessibility of this information often relies on the physical presence of technical and medical specialists in the OR, which is increasingly difficult due to the number of limitations imposed by the COVID emergency to avoid overcrowded environments or external personnel. Here, we analyze several scenarios where we equipped OR personnel with augmented reality (AR) glasses, allowing a remote specialist to guide OR operations through voice and ad-hoc visuals, superimposed to the field of view of the operator wearing them. Methods: This study is a preliminary case series of prospective collected data about the use of AR-assistance in spine surgery from January to July 2020. The technology has been used on a cohort of 12 patients affected by degenerative lumbar spine disease with lumbar sciatica co-morbidities. Surgeons and OR specialists were equipped with AR devices, customized with P2P videoconference commercial apps, or customized holographic apps. The devices were tested during surgeries for lumbar arthrodesis in a multicenter experience involving author's Institutions. Findings: A total number of 12 lumbar arthrodesis have been performed while using the described AR technology, with application spanning from telementoring (3), teaching (2), surgical planning superimposition and interaction with the hologram using a custom application for Microsoft hololens (1). Surgeons wearing the AR goggles reported a positive feedback as for the ergonomy, wearability and comfort during the procedure; being able to visualize a 3D reconstruction during surgery was perceived as a straightforward benefit, allowing to speed-up procedures, thus limiting post-operational complications. The possibility of remotely interacting with a specialist on the glasses was a potent added value during COVID emergency, due to limited access of non-resident personnel in the OR. Interpretation: By allowing surgeons to overlay digital medical content on actual surroundings, augmented reality surgery can be exploited easily in multiple scenarios by adapting commercially available or custom-made apps to several use cases. The possibility to observe directly the operatory theater through the eyes of the surgeon might be a game-changer, giving the chance to unexperienced surgeons to be virtually at the site of the operation, or allowing a remote experienced operator to guide wisely the unexperienced surgeon during a procedure.

Maximal access surgery for posterior lumbar interbody fusion with divergent, cortical bone trajectory pedicle screws: a good option to minimize spine access and maximize the field for nerve decompression.

BACKGROUND: First advocated by Santoni et al. in 2009, the cortical bone trajectory pedicle screw technique is an alternative to the traditional, convergent technique that shows comparable biomechanical features and potentially requires less aggressive tissue retraction. Aim of this therapy note is to describe this new technique focusing on main advantages and limitations. METHODS: The authors provide a detailed description of the surgically relevant anatomy focusing on the positioning of the cortical trajectory screws. The surgical technique is then described in a precise step-by-step manner, stressing complication avoidance. RESULTS: The maximal access surgery posterior lumbar interbody fusion approach is a safe, reproducible procedure allowing for a traditional lumbar spine approach with the benefits of minimal facet joint manipulation and potentially preserving part of their neural innervation and a large part of the paraspinous musculature. CONCLUSIONS: A dedicated self-retaining retractor and directional neuromonitoring may guide surgeons during the procedure. Nevertheless, the surgeon's knowledge of anatomical landmarks, response to visual and tactile cues and intraoperative decision-making skills remain of paramount importance.

Say "no" to spinal cord injury: is nitric oxide an option for therapeutic strategies?

PURPOSE: a literature review was made to investigate the role of nitric oxide (NO) in spinal cord injury, a pathological condition that leads to motor, sensory, and autonomic deficit. Besides, we were interested in potential therapeutic strategies interfering with NO mechanism of secondary damage. MATERIALS: A literature search using PubMed Medline database has been performed. RESULTS: excessive NO production after spinal cord injury promotes oxidative damage perpetuating the injury causing neuronal loss at the injured site and in the surrounding area. CONCLUSION: different therapeutic approaches for contrasting or avoiding NO secondary damage have been studied, these include nitric oxide synthase inhibitors, compounds that interfere with inducible NO synthase expression, and molecules working as antioxidant. Further studies are needed to explain the neuroprotective or cytotoxic role of the different isoforms of NO synthase and the other mediators that take part or influence the NO cascade. In this way, it would be possible to find new therapeutic targets and furthermore to extend the experimentation to humans.