Tissue engineering for total meniscal substitution : Animal study in sheep model

Objective: The aim of the study was to investigate the use of a novel hyaluronic acid/polycaprolactone material for meniscal tissue engineering and to evaluate the tissue regeneration after the augmentation of the implant with expanded autologous chondrocytes. Two different surgical implantation techniques in a sheep model were evaluated. Methods: Twenty-four skeletally mature sheep were treated with total medial meniscus replacements, while two meniscectomies served as empty controls. The animals were divided into two groups: cell-free scaffold and scaffold seeded with autologous chondrocytes. Two different surgical techniques were compared: in 12 animals, the implant was sutured to the capsule and to the meniscal ligament; in the other 12 animals, also a transtibial fixation of the horns was used. The animals were euthanized after 4 months. The specimens were assessed by gross inspection and histology. Results: All implants showed excellent capsular ingrowth at the periphery. Macroscopically, no difference was observed between cell-seeded and cell-free groups. Better implant appearance and integrity was observed in the group without transosseous horns fixation. Using the latter implantation technique, lower joint degeneration was observed in the cell-seeded group with respect to cell-free implants. The histological analysis indicated cellular infiltration and vascularization throughout the implanted constructs. Cartilaginous tissue formation was significantly more frequent in the cell-seeded constructs. Conclusion: The current study supports the potential of a novel HYAFF/polycaprolactone scaffold for total meniscal substitution. Seeding of the scaffolds with autologous chondrocytes provides some benefit in the extent of fibrocartilaginous tissue repair

Novel nano-composite multi-layered biomaterial for the treatment of multifocal degenerative cartilage lesions

We report on a 46-year-old athletic patient, previously treated with anterior cruciate ligament reconstruction, with large degenerative chondral lesions of the medial femoral condyle, trochlea and patella, which was successfully treated with a closing-wedge high tibial osteotomy and the implant of a newly developed biomimetic nanostructured osteochondral bioactive scaffold. After 1 year of follow-up the patient was pain-free, had full knee range of motion, and had returned to his pre-operation level of athletic activity. MRI evaluation at 6 months showed that the implant gave a hyaline-like signal as well as a good restoration of the articular surface, with minimal subchondral bone oedema. Subchondral oedema was almost non-visible at 12 months

Femoral fracture following knee ligament reconstruction surgery due to an unpredictable complication of bioabsorbable screw fixation: a case report and review of literature

We report an unusual case of femoral fracture from minimal trauma, due to the rapid disappearance of a bioabsorbable interference screw used for reconstruction of the posterolateral corner of the knee. The literature on bone tunnel fractures following knee ligament reconstruction surgery is also reviewed

Platelet autologous growth factors decrease the osteochondral regeneration capability of a collagen-hydroxyapatite scaffold in a sheep model

Background: Current research aims to develop innovative approaches to improve chondral and osteochondral regeneration. The objective of this study was to investigate the regenerative potential of platelet-rich plasma (PRP) to enhance the repair process of a collagen-hydroxyapatite scaffold in osteochondral defects in a sheep model. Methods: PRP was added to a new, multi-layer gradient, nanocomposite scaffold that was obtained by nucleating collagen fibrils with hydroxyapatite nanoparticles. Twenty-four osteochondral lesions were created in sheep femoral condyles. The animals were randomised to three treatment groups: scaffold, scaffold loaded with autologous PRP, and empty defect (control). The animals were sacrificed and evaluated six months after surgery. Results: Gross evaluation and histology of the specimens showed good integration of the chondral surface in both treatment groups. Significantly better bone regeneration and cartilage surface reconstruction were observed in the group treated with the scaffold alone. Incomplete bone regeneration and irregular cartilage surface integration were observed in the group treated with the scaffold where PRP was added. In the control group, no bone and cartilage defect healing occurred; defects were filled with fibrous tissue. Quantitative macroscopic and histological score evaluations confirmed the qualitative trends observed. Conclusions: The hydroxyapatite-collagen scaffold enhanced osteochondral lesion repair, but the combination with platelet growth factors did not have an additive effect; on the contrary, PRP administration had a negative effect on the results obtained by disturbing the regenerative process. In the scaffold + PRP group, highly amorphous cartilaginous repair tissue and poorly spatially organised underlying bone tissue were found

Enhancing Biological and Biomechanical Fixation of Osteochondral Scaffold: A Grand Challenge

Osteoarthritis (OA) is a degenerative joint disease, typified by degradation of cartilage and changes in the subchondral bone, resulting in pain, stiffness and reduced mobility. Current surgical treatments often fail to regenerate hyaline cartilage and result in the formation of fibrocartilage. Tissue engineering approaches have emerged for the repair of cartilage defects and damages to the subchondral bones in the early stage of OA and have shown potential in restoring the joint's function. In this approach, the use of three-dimensional scaffolds (with or without cells) provides support for tissue growth. Commercially available osteochondral (OC) scaffolds have been studied in OA patients for repair and regeneration of OC defects. However, some controversial results are often reported from both clinical trials and animal studies. The objective of this chapter is to report the scaffolds clinical requirements and performance of the currently available OC scaffolds that have been investigated both in animal studies and in clinical trials. The findings have demonstrated the importance of biological and biomechanical fixation of the OC scaffolds in achieving good cartilage fill and improved hyaline cartilage formation. It is concluded that improving cartilage fill, enhancing its integration with host tissues and achieving a strong and stable subchondral bone support for overlying cartilage are still grand challenges for the early treatment of OA

Arthroscopic second generation autologous chondrocyte implantation at 48 months follow-up

none7openE. Kon; G. Filardo; M. Delcogliano; S. Zaffagnini; C. Montaperto; F. Iacono; M. MarcacciE. Kon; G. Filardo; M. Delcogliano; S. Zaffagnini; C. Montaperto; F. Iacono; M. Marcacc

IKDC or KOOS? Which measures symptoms and disabilities most important to postoperative articular cartilage repair patients?

BACKGROUND: The relevance of knee-specific subjective measures of outcome to patients has not been evaluated for cartilage repair procedures. PURPOSE: The aim of this study was to identify which instrument out of the Knee injury Osteoarthritis Outcome Score and the International Knee Documentation Committee Subjective Knee Form measures symptoms and disabilities most important to postoperative articular cartilage repair patients. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Data were collected from 58 participants of an Internet knee forum via a self-reported online questionnaire consisting of demographic and surgical data, the Tegner activity scale, and 49 consolidated items from the Knee injury Osteoarthritis Outcome Score and the International Knee Documentation Committee Subjective Knee Form. Item importance, frequency, and frequency-importance product were calculated. RESULTS: Overall, the International Knee Documentation Committee Subjective Knee Form was the highest scoring instrument in all categories. However, 2 of the Knee injury Osteoarthritis Outcome Score subscales ("function in sport and recreation" and "knee-related quality of life") scored higher on mean importance and frequency-importance product than the overall International Knee Documentation Committee Subjective Knee Form score. CONCLUSION: The International Knee Documentation Committee Subjective Knee Form provided the best overall measure of symptoms and disabilities that are most important to this population of postoperative articular cartilage repair patients. This brings into question the validity of using the Knee injury Osteoarthritis Outcome Score in shorter-term--less than 10 years--studies. Issues related to sports activity appear to be highly valued and very pertinent to evaluation of outcomes for this patient group

Midterm results of a combined biological and mechanical approach for the treatment of a complex knee lesion

Complex fractures of the tibial plateau are difficult to treat and present a high complication rate