Role of Matrix Metalloproteinase (MMP) 2 and MMP-9 in Soft Tissue Sarcoma

BACKGROUND: We investigated the expression of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in malignant fibrous histiocytoma (MFH), and determined whether these could be useful as prognostic factors. METHODS: Among patients treated from 1993 to 2007, 30 cases of MFH were evaluated. Immunohistochemical staining was performed for MMP-2, MMP-9, TIMP-1, and TIMP-2 using paraffin wax-embedded blocks of MFH tissues. Reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot and zymography were performed using fresh tissues obtained from 17 of the 30 cases. The levels of MMP and TIMP expression were compared between the MFH and normal control groups, and between non-metastatic and metastatic MFH groups. RESULTS: Expression levels of MMP-2, MMP-9, TIMP-1, and TIMP-2 were higher in the MFH group than the control group by RT-PCR, Western blotting, and zymography. Immunohistochemical staining revealed that MMP-2 and MMP-9 protein expression was higher in the metastatic than in the non-metastatic group. The expression levels of MMP-2 and TIMP-1 were significantly higher in the metastatic than in the non-metastatic group (p 0.05). Finally, gelatin zymography analysis showed that the expression levels of the pro- and active forms of MMP-2 were significantly higher in the metastatic group (p 0.05). CONCLUSIONS: These results suggest that MMP-2, MMP-9, TIMP-1, and TIMP-2 may have important roles in the development and progression of MFH, and that the degree of expression of these metalloproteinases and their inhibitors, especially MMP-2, could be useful as prognostic factors related to metastasis in MFH.

Growth Expectation in Children: Leg Length Discrepancy Related with Bone Tumor in Children / 대한골관절종양학회지

The main goals of treatment of malignant bone tumor are the prolongation of life survival and the improvement of quality of life. In growing children, however, leg length discrepancy (LLD) is one of major problem in the treatment of malignant bone tumors. Therefore, the precise understanding of growth in children is essential, and the prediction of LLD is critical in deciding the time and options of surgery. In addition, to use the adequate method of growth expectation, periodic follow-up and collaboration with patient's parents are needed.

The Treatment of Infected Nonunions of Femur using Sequestrectomy and Distraction Osteogenesis / 대한정형외과학회잡지

PURPOSE: From this study we are to know the result of distraction osteogenesis for infected nonunions of femur using sequestrectomy and Ilizarov external fixator. MATERIALS AND METHODS: 17 patients who had distraction osteogenesis using external fixator and also had more than 2.5 cm bone loss after sequestrectomy for having infected nonunions of femur from 1991 to 2005. Their average age was 32.4 (range, 10-60) years and mean follow up period was 22 (range, 14-36) months. We used Healing index as an index for bone formation. The results were divided into bone results and functional results and analyzed by grading. Also we estimated the complication according to the Paley's classification. RESULTS: After seqestrectomy, bone defect was ranged from 5cm to 13 cm (average, 7.3 cm) and The average of transportation was 5.8 cm (range, 3-10 cm). HI was 47.4 (27.17-65.80) days/cm. Solid bony union occurred in the all cases after surgery but, 4 cases needed bone graft at docking site. According to the final examination there were 2 cases with leg-length discrepancy that is bigger than 2.5 cm and the average size of was 1.0 cm. CONCLUSION: We consider distraction osteogenesis using Ilizarov external fixator as useful method to restore bone loss caused after sequestrectomy for infected nonunions of femur.

Treatment of Metaphyseal Pathologic Fractures of Long Bone Using Locking Compression Plate in Children / 대한정형외과학회잡지

PURPOSE: To evaluate the results of operative treatment for metaphyseal pathologic fracture of long bone in children using Locking Compression Plate (LCP). MATERIALS AND METHODS: Six children were enrolled in this study. The locations of fracture were proximal femur in five children and distal femur in one child. Pathologic diagnosis was aneurysmal bone cyst, in three children and simple bone cyst, enchondroma, and nonossifying fibroma, in other three children. All six children were underwent curettage of bone lesion and bone grafting, then the fractures were internally fixed using LCP. RESULTS: All fractures were united at six to ten weeks after operation. Healing of bone lesions except one case was observed. There were no mechanical complications, no loss of reduction and malunion. Also, we couldn't find any complication associated with physeal injury, such as leg length discrepancy of lower extremities. CONCLUSION: Internal fixation of metaphyseal pathologic fracture of long bone using LCP in children is technically easy and offers secure fixation despite anatomic and biologic characteristics of this type of fracture due to biologic and biomechanical advantages of LCP.

The Usefulness of Calcium Sulfate in Treatment of Benign Bone Tumor / 대한정형외과학회잡지

PURPOSE: This study evaluated the results of the curettage and grafting of calcium sulfate for the treatment of a benign bone tumor to determine its efficacy as a bone graft substitute. MATERIALS AND METHODS: Thirty six cases of calcium sulfate(Osteoset(R)) grafting for bone defect after curettage of benign bone tumor were evaluated. There were 21 males and 15 females with a mean age of 23 years (6-64). There were 23, 10 and 3 cases grafted with the Osteoset only, the Osteoset with allografts and the Osteoset with autografts, respectively. The average follow up duration was 19 months (12-49). The process of bone formation was observed and the times for graft absorption and complete bone formation were assessed. In addition, the time of bone formation was compared according to the patients' age, size of lesion, and grafting method, and the development of complications was observed. RESULTS: Complete bone formation was observed in 34 (94.4%) out of 36 cases. The groups of younger patients, smaller size of lesion and grafting of Osteoset(R) only showed more rapid bone formation. However, there was no statistical significance. There was one case of soft tissue calcification observed. CONCLUSION: Calcium sulfate is an effective substitute for an autogenous bone graft in the case of the treatment of a benign bone tumor, particularly in the case of an insufficient graft, such as in children and in those with a large bone defect. This method is a safe method that prevents complications in the donor site.

Bone Tumors Specific in Children

Primary bone tumors in pediatric age group are uncommon, and even when they do occur, they are usually benign. The primary malignant tumors that occur predominantly in children are two bone tumors, namely, osteosarcoma and Ewing's sarcoma. An adequate history and physical examination are the first and most important steps in evaluating a patient with a bone tumor. All suspected bone tumors should be evaluated initially with plain roentgenograms. Then the additional diagnostic studies, such as computed tomography(CT), magnetic resonance imaging(MRI) and technetium bone scan can be used, if necessary. Biopsy should be the last step in evaluation. Most of benign bone tumors usually do not require treatment other than a periodic follow-up evaluation. The optimal treatment of the malignant bone tumor often requires a combination of radiation therapy, chemotherapy, and wide surgical excision or amputation. Early detection of a malignant bone tumor not only may make the difference between life and death but also may allow successful salvage surgery rather than amputation of the limb.

Restoration of Joint Space of the Knee After High Tibial Osteotomy

PURPOSE: The purpose of this study was to evaluate whether the medial joint space could be restored by HTO in osteoarthritic knee associated with varus deformity and to evaluate its clinical results. MATERIALS AND METHODS: HTO for medial gonarthrosis was performed in 65 knee joints of 59 patient. The median follow-up period was 36 months. The femoro-tibial angle(FTA) and joint space distance of medial and lateral compartment of the knee was measured on the weight-bearing antero-posterior plain radiogram. And the clinical results were evaluated by HSS knee score composed of pain, function, range of motion, muscle strength, flexion deformity and instability. RESULTS: Medial joint space distance was restored to 2.9 mm in average at postoperative 3 years from 1.8 mm in average preoperatively. Also the lateral joint space distance was maintained without decrease. FTA was corrected from varus 6.3 degree in average preoperatively to valgus 7.3 degree in average at three years postoperatively. HSS score was improved from 69.1 point in average preoperatively to 95 points in average at three years postoperatively. The group of increased joint space distance showed more improved HSS score and more corrected FTA than the unchanged group(p<0.05). When the change of HSS score was compared according to the postoperative FTA, the group, FTA was corrected 7 degree or more had more improved clinical results and more increased joint space distance(p<0.05). Complications were pain or tenderness on the fibular osteotomy site in seven knees, nonunion of fibular osteotomy in seven knee, transient peroneal paresis in four knees and delayed union of tibial osteotomy in one knee. CONCLUSION: At three years follow up after HTO, there was restoration of joint space of the medial compartment of the knee. Also we found the fact that the joint space widening was correlated with clinical improvement. These results suggest that the correction angle of valgus 7 degree or more may have better clinical outcomes.