METHODS: The decellularization was achieved using a developed closed sonication treatment system for 10 hrs, and continued with a washing process for 5 days. For the control, a simple immersion treatment was set as a benchmark to compare the decellularization efficiency. Histological and biochemical assays were conducted to investigate the cell removal and retention of the vital extracellular matrix. Surface ultrastructure of the prepared scaffolds was evaluated using scanning electron microscope at 5,000× magnification viewed from cross and longitudinal sections. In addition, the biomechanical properties were investigated through ball indentation testing to study the stiffness, residual forces and compression characteristics. Statistical significance between the samples was determined with p-value =0.05.
RESULTS: Histological and biochemical assays confirmed the elimination of antigenic cellular components with the retention of the vital extracellular matrix within the sonicated scaffolds. However, there was a significant removal of sulfated glycosaminoglycans. The surface histoarchitecture portrayed the preserved collagen fibril orientation and arrangement. However, there were minor disruptions on the structure, with few empty micropores formed which represented cell lacunae. The biomechanical properties of bioscaffolds showed the retention of viscoelastic behavior of the scaffolds which mimic native tissues. After immersion treatment, those scaffolds had poor results compared to the sonicated scaffolds due to the inefficiency of the treatment.
CONCLUSION: In conclusion, this study reported that the closed sonication treatment system had high capabilities to prepare ideal bioscaffolds with excellent removal of cellular components, and retained extracellular matrix and biomechanical properties.
Materials and Methods: The Nordic Musculoskeletal Questionnaire was sent out to all orthopaedic consultants and residents at two institutions in Singapore, via an email link to an online survey. Separately, further questions on symptom description, severity and treatment were surveyed. Additional information like age, gender, height and weight were obtained as well.
Results: A total of 87.5% respondents have at least one injury. Neck symptoms (66.1%) were the most prevalent, and back symptoms had the highest median severity score (4.5/10). The 74.1% of these injuries were reported as directly attributable to work. Age was found to be associated with an increase in the total number of anatomical areas affected (p = 0.016). A seated operating position was associated with more severe back pain (p = 0.040).
Conclusion: There is a high prevalence of occupational injuries sustained in our population of orthopaedic surgeons. Neck symptoms, followed by back and wrist symptoms, were the predominant symptoms in our population. Targeted ergonomic interventions may be considered to prevent specific musculoskeletal injuries in our population of orthopaedic surgeons.