Short Term Clinical Results of Anatomical Reconstruction in the Posterolateral Corner of the Knee using Achilles Tendon Allograft / 대한정형외과학회잡지

PURPOSE: The purpose of this study was to evaluate the short term clinical results of the new anatomical reconstruction including 3 major posterolateral structures of the knee using a split Achilles allograft. MATERIALS AND METHODS: Eleven knees with posterolateral rotary instability underwent new anatomical posterolateral reconstruction between January 2002 and June 2003. The clinical results were assessed using the Lysholm score and Tegner activity level scales and physical examinations including posterolateral drawer test, dial tests at 30 and 90 degrees of knee flexion, varus stress tests at 0 and 30 degrees of knee flexion. RESULTS: Follow-up averaged 26 months (range, 12 to 29 months). The mean preoperative Lysholm score was 38.6 and at the time of latest follow-up, the mean score was improved to 72.5. The mean preoperative Tegner activity level was improved from 1.6 points to 3.3. Ten out of 11 patients showed negative conversion of the posterolateral drawer test and varus stress test at 30 degrees of flexion postoperatively. All patients, who showed positive signs on the external rotation-dial test at 30 degrees of knee flexion preoperatively, improved postoperatively. In eight patients, preoperative positive signs of varus stress tests at 0 degrees of knee flexion and the external rotation-dial test at 90 degrees of knee flexion disappeared postoperatively. CONCLUSION: This study suggests that the new anatomical reconstruction of posterolateral corner of knee is a reliable method providing excellent stability and satisfactory short term clinical results.

Gait Patterns According to the Transverse Plane Deformities in Spastic Diplegia: A Preliminary Report / 대한정형외과학회잡지

PURPOSE: To understand the relationship between the gait patterns in transverse plane and the transverse plane deformities. MATERIALS AND METHODS: We evaluated the clinical, radiological, and three-dimensional gait analysis data of 152 spastic diplegics with transverse plane deformities. We define the transverse plane deformities as follows: 1) femoral anteversion > or =30 degrees, 2) thigh foot angle or =25 degrees, 3) severe foot deformities that could affect the foot progression angle. RESULTS: We classified gait patterns of spastic diplegics into 6 groups on the base of pelvic compensation and foot progression angle, and divided anatomic characteristics into symmetric and asymmetric type. Among the gait patterns, pattern I-A (in-toeing with pelvic compensation) and II-A (in-toeing without pelvic compensation) were most prevalent. Femoral antetorsion was the most frequent torsional deformities, whereas valgus of foot was second most. CONCLUSION: We classified the gait patterns and analyzed the relationship between each gait pattern and types of torsional deformities.

Rigid Stepped Plate (RSP) for the Internal Fixation of the High Tibial Osteotomy / 대한정형외과연구학회지

PURPOSE: To compare the fixation power of the newly devised RSP (rigid stepped plate) with the L-plate by mechanical study and to prove the efficacy of the RSP. MATERIALS AND METHODS: Lateral closing wedge proximal tibial osteotomy was performed on the 10-monthsold porcine tibiae, which were fixed by 15 L-plates and 15 RSP's. Each group of 5 pairs of the specimen were applied to the Instron apparatus and loaded by compression, valgus, and varus bending. The fixation power was compared by the stiffness of each construct. RESULTS: Specimen fixed by the RSP's showed larger stiffness than those fixed by the L-plate. Even though the difference was not statistically significant in compression (p=0.465), it was statistically significant in valgus (p=0.047) and varus (p=0.009) bending. CONCLUSION: The RSP can be applied with minimal skin incision, will provide firm initial fixation to the osteotomy site, and seems to enable early range of motion exercise. It will improve the outcome of proximal tibial osteotomy by preventing excessive soft tissue dissection and complications resulting from long-term immobilization of the knee joint.

Evaluation of Chondrogenesis in Collagen/Chitosan/Glycosaminoglycan Scaffolds for Cartilage Tissue Engineering / 대한정형외과연구학회지

PURPOSE: The scaffold is essential for cartilage tissue engineering. Collagen, chitosan, or glycosaminoglycan( GAG) has separately been proposed as in vitro scaffolds. However, the influence of collagen:chitosanchondroitin sulfate(Col:Chi-CS) composites on cell behavior has not yet been thoroughly examined. Therefore, the aim of this study is to develop a novel Col:Chi-CS blended scaffold that binds covalently with CS for cartilage tissue engineering. MATERIALS AND METHODS: The behavior of rabbit chondrocytes seeded in vitro into collagen/chitosan/GAG scaffolds with different chitosan contents (collagen:chitosan ratios of 20:1, 5:1, and 1.25:1) was investigated. The porous scaffolds containing collagen and chitosan were fabricated by using a freeze drying technique and crosslinked using 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide(EDC) in the presence of CS. The physicochemical/ mechanical properties of scaffolds were determined by analyzing scanning electron microscopy, compression modulus, immobilized GAG content, and water-binding capacity. Rabbit chondrocytes seeded onto these scaffolds were cultured for 1, 3, 7, and 14 days. The cell proliferation rate was evaluated with 3H-thymidine uptake and total GAG content assay was done via DMB assay using ELISA method. For the histological assessment of extracellular matrix, staining with safranin-O/fast green and immunohistochemistry were used. RESULTS: Scanning electron microscope(SEM) views of the scaffolds showed that all three had interconnected pores of mean diameter 164, 353, and 567 micrometer at collagen:chitosan ratios of 20:1, 5:1, and 1.25:1. GAG was covalently bound onto these scaffolds at 6.4%(w/w) in all three cases, i.e., regardless of chitosan content. However, increased chitosan content resulted in enhanced mechanical properties and increased pore size. Biochemical analysis of these scaffolds showed that proliferation rate and GAG synthesis increased with time, and this became most significant in the collagen:chitosan(20:1)-CS scaffold on day 14. The histology of the cell-seeded constructs showed a significantly higher percentage of cells with spherical morphology, which is specific to mature chondrocyte, especially in the collagen:chitosan(20:1)-CS scaffold at each time point. This finding was consistent with the observation that the pericellular matrix was stained positive for proteoglycans and type II collagen on day 14. CONCLUSION: The novel collagen:chitosan(20:1)-CS scaffold seems to be a useful carrier material for cartilage tissue engineering.

Integrin alphavbeta3, alpha5beta1 Effects on Cell Proliferation and Migration in Human Osteosarcoma / 대한정형외과연구학회지

BACKGROUND: We investigate the influence of cell surface adhesion receptor integrin alphavbeta3, alpha5beta1 contributes to proliferation and migration of tumor cell in osteosarcoma for carves out a new treatment model by regulation of integrin roles in human osteosarcoma. MATERIALS AND METHODS: We performed proliferation assay, total 11 cell lines including 7 osteosarcoma cell lines established from patients and 4 osteosarcoma standard cell lines. Murine monoclonal anti-alpha5beta1 and anti-alphavbeta3 (Chemicon International Inc. Temecula, CA) were used for growth inhibition assays. We also performed cell motility assay by using the Boyden chamber to evaluate the effect of integrin mediated cell migration. We used the HOS standard osteosarcoma cell lines and each separates contained serum free media with mouse IgG1 negative control antibody, anti-alpha5beta1 antibody and anti-alphavbeta3 antibody. RESULTS: Proliferation of cells decreased significantly in 10 out of 11 cell lines when blocking with alphavbeta3 or alpha5beta1 respectively. Blocking with anti-alphavbeta3 antibody decreased significantly tumor cell proliferation in 10 cell lines. Among the 10 cell lines, 7 cell lines showed significantly more decrease of proliferation with anti-alphavbeta3 antibody than with anti-alpha5beta1antibody. Blocking with anti-alpha5beta1 antibody decreased significantly tumor cell proliferation in 10 cell lines. Among the 10 cell lines, 3 cell lines showed significantly more decrease of proliferation with anti-alpha5beta1 antibody than with anti-alphavbeta3 antibody. Including statistically not significant 2 cell lines the growth inhibition of osteosarcoma cell lines was more obvious (10 out of 11) in blocking with anti-alphavbeta3 antibody. The migration of cells was significantly decreased when blocked with anti-alpha5beta1 antibody and anti-alphavbeta3 antibody. CONCLUSION: Under the based on the integrin alphavbeta3, alpha5 beta1 are central role on proliferation and migration of osteosarcoma cells, we could be more approach to new therapeutic endeavors with antibody to integrin alphavbeta3, alpha5beta1 molecular target of osteosarcoma.