This study used the finite element method(FEM) to investigate how pressure on the lumbar spine changes during dynamic movements in different postures: standing, erect sitting on a chair, slumped sitting on a chair, and sitting on the floor. Three load modes (flexion, lateral bending, and axial rotation) were applied to the FEM, simulating movements of the lumbar spine. Results showed no significant difference in pressure distribution on the annulus fiber and nucleus pulposus, representing intradiscal pressure, as well as on the cortical bone during movements between standing and erect sitting postures. However, both slumped sitting on a chair and sitting on the floor postures significantly increased pressure on the nucleus pulposus, annulus fibrosus, and cortical bone in all three movements when compared to standing or erect sitting on a chair. Notably, sitting on the floor resulted in even higher pressure on the nucleus pulposus and annulus fibers compared to slumped sitting on a chair. The decreased lumbar lordosis while sitting on the floor led to the highest increase in pressure on the annulus fiber and nucleus pulposus in the lumbar spine. In conclusion, maintaining an erect sitting position with increased lumbar lordosis during seated activities can effectively reduce intradiscal pressure and cortical bone stress associated with degenerative disc diseases and spinal deformities.

Han JS, et al. Brain Neurorehabil. 2024 Jul;17(2):e13. https://doi.org/10.12786/bn.2024.17.e13

Neuromyelitis optica spectrum disease (NMOSD) is a rare autoimmune disorder of the central nervous system characterized by optic neuritis, myelitis, or brain lesions. Its symptoms overlap with those of multiple sclerosis (MS), making a diagnosis of NMOSD challenging. Here, we report a rare case of NMOSD-induced complete spinal cord injury following COVID-19 vaccination. A 52-year-old female patient developed NMOSD-induced complete spinal cord injury after receiving their third dose of the Pfizer–BioNTech COVID-19 vaccine (BNT162b2). Despite the initial diagnosis of complete spinal cord injury, the patient underwent intensive treatment, including rituximab therapy and rehabilitation. As a result, she made a full recovery and transitioned from the ASIA Impairment Scale(AIS)-A to AIS-E. The remarkable neurological recovery from complete spinal cord injury to functional independence highlights the efficacy of a comprehensive treatment approach. In addition, this case emphasizes the need to recognize NMOSD as a potential adverse outcome of COVID-19 vaccination and emphasizes the importance of early diagnosis, timely intervention, and thorough rehabilitation for optimizing patient results. Further case reports and studies are needed to investigate the association between COVID-19 vaccination and the occurrence of NMOSD.

This case series presents two cases of acute acalculous cholecystitis (AAC)—a rare condition—in young women with central nervous system (CNS) lesions. Both patients had significant neurologic deficits and no well-known risk factors or presence of comorbidities (such as diabetes or a history of cardiovascular or cerebrovascular disease). Early diagnosis is important in cases of AAC owing to its high mortality rate; however, due to neurological deficits in our cases, accurate medical and physical examinations were limited, thereby leading to a delay in the diagnosis. The first case was of a 33-year-old woman with multiple fractures and hypovolemic shock due to a traumatic accident; she was diagnosed with hypoxic brain injury. The second case was of a 32-year-old woman with bipolar disorder and early-onset cerebellar ataxia who developed symptoms of impaired cognition and psychosis; she was later diagnosed with autoimmune encephalopathy. In the first case, the duration between symptom onset and diagnosis was 1 day, but in the second case, it was 4 days from diagnosis based on the occurrence of high fever. We emphasize that if a young woman presents with high fever, the possibility of AAC should be considered, particularly if a CNS lesion is present because it may pose difficulty in the evaluation of typical symptoms of AAC. Careful attention is thus required in such cases.