ABSTRACT
PURPOSE: The role of mesenchymal stem cells (MSC) in supporting the formation of new meniscal tissue in a meniscal scaffold is not well understood. The objective of this study was to assess the quality of the meniscal tissue produced in a fibronectin (FN)-coated polyurethane (PU) meniscal scaffold after a meniscal injury was made in an experimental rabbit model. METHODS: Twelve New Zealand white rabbits were divided in two groups after performing a medial meniscectomy of the anterior horn. In group 1, the meniscal defect was reconstructed with a non-MSC supplemented FN-coated PU scaffold. On the other hand, the same scaffold supplemented with MSCs was used in group 2. The animals were sacrificed at 12 week after index surgery. A modified scoring system was used for histological assessment. This new scoring (ranging from 0 to 15) includes a structural evaluation (meniscal scaffold interface and extracellular matrix production) and tissue quality evaluation (proteoglycan and type I-collagen content). RESULTS: The meniscal scaffold was found loose in the joint in three cases, corresponding to two cases in group 1 and 1 case in group 2. No differences were observed between the groups in terms of the total score (7.0 ± 0.9 vs. 9.4 ± 2.6, p = 0.09). However, differences were observed in group 2 in which 2 out of the 5 scored items, scaffold integration (1 ± 0.0 vs. 1.9 ± 0.6, p = 0.03) and proteoglycan production (1.2 ± 0.3 vs. 2.4 ± 0.2, p = 0.001). A trend to a higher production of Type I-Collagen production was also observed in group 2 (1.1 ± 0.4 vs. 1.4 ± 0.7, p = 0.05). CONCLUSION: In a rabbit model at 12 weeks, the adhesion of MSCs to a FN-coated PU scaffold improves scaffold integration, proteoglycan production and the characteristics of the new meniscal-like tissue obtained when compared to a non-supplemented scaffold. This fact could be a major step toward improving the adhesion of the MSCs to meniscal scaffolds and, consequently, the obtention of better quality meniscal tissue.
ABSTRACT
BACKGROUND: The objective of this study was to compare the total knee arthroplasty (TKA) functional outcomes and quality of life of obese and non-obese patients. METHODS: Prospective comparative study, including all patients underwent TKA in a single centre. Patients were divided into three groups: Group 1 (Gr.1) BMI <30 kg/m2, Group 2 (Gr.2) BMI ≥ 30 kg/m2 and <35 kg/m2 and Group 3 (Gr.3) BMI ≥35 kg/m2. The Knee Society score (KSS) and SF-36 scores were obtained preoperatively and at 5 years of follow-up. RESULTS: A total of 689 patients were included (72.2 ± 7 years, 76.3 % women). Overall, pre- and post-operative values of SF-36 were lower for the obese group. However the improvement obtained in the three groups was similar in all the sub-scales of the SF-36 score. KSS values were higher in the non-obese group in both periods. However the improvement obtained in this score in the three groups was similar (Gr.1; 70.21 ± 34.31, Gr.2; 66.53 ± 34.93, Gr.3; 60.94 ± 38.47, n.s.). CONCLUSIONS: Although non-obese patients obtained better functional and reported quality of life scores than obese patients, there were no differences in the gain of quality of life and knee functionality between both groups at 5-years of follow-up. This is one of the largest series in a single centre published in literature and confirms the results obtained by other authors. Taking into account the different outcomes obtained, surgery should not be denied to patients that are obese, given that they obtained similar benefit than non-obese patients.
