Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Study Design: Broad narrative review. Objective: To review and summarize the current literature on guidelines, outcomes, techniques and indications surrounding multiple modalities of minimizing blood loss in spine surgery. Methods: A thorough review of peer-reviewed literature was performed on the guidelines, outcomes, techniques, and indications for multiple modalities of minimizing blood loss in spine surgery. Results: There is a large body of literature that provides a consensus on guidelines regarding the appropriate timing of discontinuation of anticoagulation, aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), and herbal supplements prior to surgery. Additionally, there is a more heterogenous discussion the utility of preoperative autologous blood donation facilitated by erythropoietin and iron supplementation for healthy patients slated for procedures with high anticipated blood loss and for whom allogeneic transfusion is likely. Intraoperative maneuvers available to minimize blood loss include positioning and maintaining normothermia. Tranexamic acid (TXA), bipolar sealer electrocautery, and topical hemostatic agents, and hypotensive anesthesia (mean arterial pressure (MAP) <65 mm Hg) should be strongly considered in cases with larger exposures and higher anticipated blood loss. There is strong level 1 evidence for the use of TXA in spine surgery as it reduces the overall blood loss and transfusion requirements. Conclusion: As the volume and complexity of spinal procedures rise, intraoperative blood loss management has become a pivotal topic of research within the field. There are many tools for minimizing blood loss in patients undergoing spine surgery. The current literature supports combining techniques to use a cost- effective multimodal approach to minimize blood loss in the perioperative period.

Ossification of the posterior longitudinal ligament (OPLL) is a rare but potentially devastating cause of degenerative cervical myelopathy (DCM). Decompressive surgery is the standard of care for OPLL and can be achieved through anterior, posterior, or combined approaches to the cervical spine. Surgical correction of OPLL via any approach is associated with higher rates of complications and the presence of OPLL is considered a significant risk factor for perioperative complications in DCM surgeries. Potential complications include dural tear (DT) and subsequent cerebrospinal fluid leak, C5 palsy, hematoma, hardware failure, surgical site infections, and other neurological deficits. Anterior approaches are technically more demanding and associated with higher rates of DT but offer greater access to ventral OPLL pathology. Posterior approaches are associated with lower rates of complications but may allow for continued disease progression. Therefore, the decision to pursue either an anterior or posterior approach to surgical decompression may be critically influenced by complications associated with each procedure. The authors critically review anterior and posterior approaches to surgical decompression of OPLL with particular focus on the complications associated with each approach. We also review the recent work in developing new surgical treatments for OPLL that aim to reduce complication incidence.

Study Design: Literature review.Objectives: Paraspinal muscle integrity is believed to play a critical role in low back pain (LBP) and numerous spinal deformity diseases and other pain pathologies. The influence of paraspinal muscle atrophy (PMA) on the clinical and radiographic success of spinal surgery has not been established. We aim to survey the literature in order to evaluate the impact of paraspinal muscle atrophy on low back pain, spine pathologies, and postoperative outcomes of spinal surgery.Methods: A review of the literature was conducted using a total of 267 articles identified from a search of the PubMed database and additional resources. A full-text review was conducted of 180 articles, which were assessed based on criteria that included an objective assessment of PMA in addition to measuring its relationship to LBP, thoracolumbar pathology, or surgical outcomes. Results: A total of 34 studies were included in this review. The literature on PMA illustrates an association between LBP and both decreased cross-sectional area and increased fatty infiltration of paraspinal musculature. Atrophy of the erector spinae and psoas muscles have been associated with spinal stenosis, isthmic spondylolisthesis, facet arthropathy, degenerative lumbar kyphosis. A number of studies have also demonstrated an association between PMA and worse postoperative outcomes. Conclusions: PMA is linked to several spinal pathologies and some studies demonstrate an association with worse postoperative outcomes following spinal surgery. There is a need for further research to establish a relationship between preoperative paraspinal muscle integrity and postoperative success, with the potential for guiding surgical decision making.

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