Performance of the Dutch clinical prediction rule for the ambulation outcome after spinal cord injury in a middle-income country clinical setting: an external validation study in the Thai retrospective cohort.

OBJECTIVE: To perform external geographic and domain validation of the clinical prediction rule (CPR) of the ambulation outcome of patients with traumatic spinal cord injury (SCI) originally developed by van Middendorp, et al. (2011) in Thais with traumatic and non-traumatic SCI. STUDY DESIGN: Retrospective cohort study. SETTING: A tertiary rehabilitation facility in Chiang Mai, Thailand. METHODS: A validation data set, including predictive (age and four neurological variables) and outcome (ambulation status) parameters was retrospectively collected from medical records of patients with traumatic and non-traumatic SCI admitted between December 2007 and December 2019. The performance of the original model was evaluated in both discrimination and calibration aspects, using an area under the receiver-operating characteristic curve (auROC) and calibration curves, respectively. RESULTS: Three hundred and thirty-three patients with SCI were included in the validation set. The prevalence of ambulators was 59% (197 of 333 participants). An auROC of 0.93 (95% CI 0.90-0.96) indicated excellent discrimination whereas the calibration curve demonstrated underestimation, especially in patients with AIS grade D. Performance of the CPR was decreased but acceptable in patients with non-traumatic SCI. CONCLUSIONS: Our external validation study demonstrated excellent discrimination but slightly underestimated calibration of the CPR of ambulation outcome after SCI. Regardless of the geographic and etiologic background of the population, the Dutch CPR could be applied to predict the ambulation outcome in patients with SCI.

Intractable postural hypotension resulting from cervical pseudomeningocele after a posterior cervical spinal surgery: a case report.

INTRODUCTION: Postural hypotension (PH) is common in patients with spinal cord injury (SCI), especially those with tetraplegia. To effectively treat PH, identifying and eliminating treatable predisposing factors of PH are prerequisites before applying any interventions. CASE PRESENTATION: We report a patient with post-acute cervical SCI who suffered from intractable PH resulting from pseudomeningocele causing unfavorable rehabilitation outcomes. A previously healthy 34-year-old man with complete C6 SCI resulting from C6-C7 fracture dislocation developed PH in the first week of the rehabilitation program. No specific predisposing factors including anemia, hyponatremia, and dehydration were identified. Non-pharmacological interventions and pharmacological treatment were administered to the patient without satisfactory result, causing a delay in rehabilitation progression. In the fourth week of rehabilitation program, a mass at the surgical site was detected. A cervical MRI revealed a large fluid collection at the posterior aspect of cervical spines with a size of 7.9 × 6.8 × 5.0 cm. A diagnosis of pseudomeningocele was made and surgical site debridement with closing dura by grafting was immediately conducted. One day after surgery, PH disappeared, and the patient could progress in his rehabilitation program and achieve his short-term goal within three weeks. CONCLUSION: Pseudomeningocele could be one of the precipitating factors of PH in patients with tetraplegia. Healthcare providers should consider investigating pseudomeningocele in patients who have intractable and unexplainable PH.

Unbiased Analysis of the Impact of Micropatterned Biomaterials on Macrophage Behavior Provides Insights beyond Predefined Polarization States.

Macrophages are master regulators of immune responses toward implanted biomaterials. The activation state adopted by macrophages in response to biomaterials determines their own phenotype and function as well as those of other resident and infiltrating immune and nonimmune cells in the area. A wide spectrum of macrophage activation states exists, with M1 (pro-inflammatory) and M2 (anti-inflammatory) representing either ends of the spectrum. In biomaterials research, cell-instructive surfaces that favor or induce M2 macrophages have been considered as beneficial due to the anti-inflammatory and pro-regenerative properties of these cells. In this study, we used a gelatin methacryloyl (GelMA) hydrogel platform to determine whether micropatterned surfaces can modulate the phenotype and function of human macrophages. The effect of microgrooves/ridges and micropillars on macrophage phenotype, function, and gene expression profile were assessed using conventional methods (morphology, cytokine profile, surface marker expression, phagocytosis) and gene microarrays. Our results demonstrated that micropatterns did induce distinct gene expression profiles in human macrophages cultured on microgrooves/ridges and micropillars. Significant changes were observed in genes related to primary metabolic processes such as transcription, translation, protein trafficking, DNA repair, and cell survival. However, interestingly conventional phenotyping methods, relying on surface marker expression and cytokine profile, were not able to distinguish between the different conditions, and indicated no clear shift in cell activation towards M1 or M2 phenotypes. This highlights the limitations of studying the effect of different physicochemical conditions on macrophages by solely relying on conventional markers that are primarily developed to differentiate between cytokine polarized M1 and M2 macrophages. We therefore propose the adoption of unbiased screening methods in determining macrophage responses to biomaterials. Our data clearly show that the exclusive use of conventional markers and methods for determining macrophage activation status could lead to missed opportunities for understanding and exploiting macrophage responses to biomaterials.