Biomimetic Scaffolds Modulate the Posttraumatic Inflammatory Response in Articular Cartilage Contributing to Enhanced Neoformation of Cartilaginous Tissue In Vivo.

Focal chondral lesions of the knee are the most frequent type of trauma in younger patients and are associated with a high risk of developing early posttraumatic osteoarthritis. The only current clinical solutions include microfracture, osteochondral grafting, and autologous chondrocyte implantation. Cartilage tissue engineering based on biomimetic scaffolds has become an appealing strategy to repair cartilage defects. Here, a chondrogenic collagen-chondroitin sulfate scaffold is tested in an orthotopic Lapine in vivo model to understand the beneficial effects of the immunomodulatory biomaterial on the full chondral defect. Using a combination of noninvasive imaging techniques, histological and whole transcriptome analysis, the scaffolds are shown to enhance the formation of cartilaginous tissue and suppression of host cartilage degeneration, while also supporting tissue integration and increased tissue regeneration over a 12 weeks recovery period. The results presented suggest that biomimetic materials could be a clinical solution for cartilage tissue repair, due to their ability to modulate the immune environment in favor of regenerative processes and suppression of cartilage degeneration.

Case Report of a Complex Chest Wall Reconstruction with a Cadaveric Achilles Tendon.

BACKGROUND Chest wall reconstruction is sometimes needed after resection of a thoracic malignancy. Various materials and techniques have been utilized to restore stability and integrity to the chest wall. We report what we believe is the first use of a cadaveric Achilles tendon to restore stability and function to the chest wall of a young woman who underwent chest wall resection and right upper lobectomy for a superior sulcus tumor. CASE REPORT A 46-year-old woman underwent resection of her first through fourth right ribs in addition to her right upper lobe for a squamous cell superior sulcus tumor. Because it was felt her right scapula provided sufficient coverage of her resultant chest wall defect, her chest wall was not reconstructed post-operatively. The patient experienced 2 episodes of scapular prolapse into her thoracic cavity several months after her resection. After the second episode, her right chest wall was successfully reconstructed with a cadaveric Achilles tendon to prevent further episodes of prolapse. CONCLUSIONS We believe this is the first description of chest wall reconstruction with a cadaveric Achilles tendon. The use of a cadaveric Achilles tendon should be considered for reconstruction of the chest wall after complex resection due to its strength characteristics, resistance to subsequent infection, and availability.

Improving the accuracy of wide resection of bone tumors and enhancing implant fit: A cadaveric study.

BACKGROUND/AIMS: Customized three-dimensional (3-D) jigs have been shown to increase the accuracy of skeletal tumor resection in comparison to freehand techniques. However, the utility of these jigs in subsequently enhancing the fit of endoprosthetic implants has yet to be determined. We hypothesized that custom jigs would improve implant fit compared to freehand resection. METHODS: Nine matched pairs of cadaveric femurs were scanned by CT. The images then had 'virtual' tumors positioned on the distal medial femoral condyle and preoperative resection plans were generated. Custom implants were designed to fit into the resected spaces and 3-D printed. Similarly, customized 3-D jigs were designed and printed for half of the femurs. Resections were then performed using the jigs or freehand. The implants were positioned in the resected femurs and the accuracy-of-fit was quantitatively assessed by re-scanning the resected femurs and calculating the deviation from the implant (in degrees) for each of the 3 cutting planes. The results were then compared between jig and freehand resections. RESULTS: For the first plane, the jig resulted in less deviation than the freehand cut, but it did not achieve statistical significance. However, for the 2nd and 3rd planes, the jigs deviated 1.78° and 2.20° from the implants compared to 4.41° and 7.96° for the freehand cuts, both of which were statistically significant improvements (p = 0.038 and p = 0.003). CONCLUSION: In summary, customized 3-D jigs were shown to improve the accuracy-of-fit between implants and host bone, moving this technology closer to clinical implementation.