Simultaneous anterior and posterior cruciate ligament reconstruction in chronic knee instabilities: surgical concepts and clinical outcome.

The purpose of this study was to evaluate the clinical results of simultaneous arthroscopically assisted reconstruction of anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) using autogenous tendon grafts in chronic knee injuries. Nineteen patients (17 men and 2 women) with chronic multi-ligamentous injuries underwent one-stage ACL and PCL reconstruction. ACL, PCL and medial collateral ligament were reconstructed in seven knees, and ACL, PCL and posterolateral structure were reconstructed in two knees. Function of the operated knee was evaluated according to the International Knee Documentation Committee (IKDC) and Lysholm scale. Anterior and posterior knee laxity was examined with a KT-2000 arthrometer. Eighteen of 19 patients were able to return for follow-up and were evaluated objectively and subjectively. The average patient age at surgery was 30.5 years, and the average postoperative follow-up was 3.5 years. No patients showed loss of knee extension more than 5 degrees , while three patients revealed loss of knee flexion more than 16 degrees . The mean postoperative total anterior-posterior side-to-side difference was 1.9 +/- 1.5 mm at 20 degrees and 2.1 +/- 1.9 mm at 70 degrees . The average of the Lysholm score was 95.1 points at the final follow-up. At the IKDC evaluation, three patients were grade A, 11 were grade B, 3 were grade C, and 1 patient was grade D. The results showed the effectiveness and safety of one-stage reconstruction of combined ligamentous injuries of the knee that can adequately restore satisfactory stability.

Ex vivo supplementation of TGF-beta1 enhances the fibrous tissue regeneration effect of synovium-derived fibroblast transplantation in a tendon defect: a biomechanical study.

The present study was conducted to test a hypothesis that the ex vivo supplementation of TGF-beta1 into medium will significantly improve the mechanical properties of the fibrous tissue regenerated in the patellar tendon defect after transplantation of cultured autologous synovium-derived fibroblasts. Thirty rabbits were divided into the following three groups. In Group A, we applied phosphate buffered saline of 0.1 ml to the defect created in the patellar tendon. In Group B, we transplanted autologous fibroblasts, which had been cultured into the tendon defect. In Group C, we transplanted autologous fibroblasts, which had been cultured with supplementation of TGF-beta1, into the tendon defect. Animals were killed at 6 weeks, and the regenerated tissue was examined for biomechanics and histology. The tangent modulus and the tensile strength of Group C were significantly higher than that of Group B, while the tensile strength of Group C was significantly lower than that of Group A. Histologically, vascular formation was abundantly found in the regenerated tissue of Groups B and C as compared to the regenerated tissues in Group A. The present study showed that transplantation of cultured autologous synovium-derived fibroblasts enhanced vascular formation in the fibrous tissue regenerated in the patellar tendon defect, while cell transplantation deteriorated the mechanical properties of the regenerated fibrous tissue. However, the ex vivo supplementation of TGF-beta1 into the medium significantly decreased mechanical deterioration of the fibrous tissue regenerated in the tendon defect after transplantation of cultured autologous synovium-derived fibroblasts.

The effect of transforming growth factor-beta on mechanical properties of the fibrous tissue regenerated in the patellar tendon after resecting the central portion.

BACKGROUND: No investigators have studied the effects of an application of growth factors on the in vivo tissue regeneration in the tendon after resecting the central portion. The purpose of this study is to clarify whether an application of transforming growth factor (TGF)-beta1 increases the mechanical properties of the regenerated tissue in the patellar tendon after resecting the central portion. METHODS: Thirty female rabbits were divided into three groups, after a 3 mm wide and 10 mm long tendon substance was resected from the central portion in the patellar tendon. In Group I, 5-ng TGF-beta1 dissolved in 0.1-ml saline was injected into the resected portion in the patellar tendon. In Group II, only 0.1-ml saline was injected into the resected portion. In Group III, nothing was injected. All animals were sacrificed at 6 weeks after surgery. Mechanical and histological evaluations were made concerning the regenerated tissue and the unresected tendon tissue in the patellar tendon. FINDINGS: Concerning the regenerated tissue, the tangent modulus and the tensile strength of Group I were significantly greater than those of Groups II and III, while there were no significant differences in these parameters between Groups II and III. INTERPRETATION: The application of TGF-beta1 significantly increases the tangent modulus and the tensile strength of the fibrous tissue regenerated in the patellar tendon after resecting the central portion. This study has provided basic important information on the utility of TGF-beta1 in the in vivo tendon regeneration.