PURPOSE : The purpose of this study is to know the ability of detecting malignant tumor tissue by Tl-201 scan, and to compare with that of Tc-99m-MIBI and Tc-99m-MDP scan. MATERIAL AND METHODS : Between February 1994 and December 1995,38 unselected patients with various bone pathologies were studied prospectively. Eighteen had malignant bone and soft tissue pathologies, while twenty had benign. All patients were studied with Tl-201, Tc-99mMIBI and Tc-99m-MDP scan prior to surgical biopsy. PICKER Prism 2000 gamma camera with high resolution parallel hole collimator was used for scanning. To avoid the interaction of isotope, the early(30min.) and delayed phase(3hrs.) of Tl-20l scan was performed first and Tc-99m-MIBI scan was performed after 30 minutes, and then Tc-99m-MDP scan 48 hours later. The scan images were visually evaluated by a blinded nuclear medicine physician. We could find true positive, true negative, false positive and false negative by the comparison of results with those of biopsy. We calculated positive and negative predictive value(%), sensitivity(%), specificity(%) and diagnostic accuracy(%) of each scan. RESULT : The results of each scan were 85.7, 100, 100, 85, 92.1% in Tl-201, 81, 94.1, 94.4, 80, 86.8% in Tc-99m-MIBI and 50, 66.7, 88.9, 20, 52.6% in Tc-99m-MDP scan. As a conclusion, Tl-201 scan was the most specific and accurate method for detecting malignant tumor tissue. Tc-99m-MIBI scan was also good for malignant tumor searching. CONCLUSION : With our results, we can use Tl-201 scan to differentiate benign from malignant tumor, and to evaluate the response of preoperative chemotherapy or radiotherapy, and to determine the residual tumor or local recurrence. For the better result, we need to have a more detail information about false positive cases and a more objective and quantitative reading technique.

The purpose of this study is a comparative evaluation of range motion, especially extension deficit between the group of total patellectomy and that of intact patella, after reconstruction of the patellar tendon in the prosthetic replacement of a proximal tibia. Between 1990 and 1994, 15 patients who had a primary malignancy on proximal tibia were operated on. All patients were evaluated clinically and radiographically. Two patients were excluded because one had a deep infection treated with arthrodesis of the knee and the other was a composite allograft. The mean follow-up of the 13 patients was 27 months(15-47), including 10 osteosarcomas, 1 chondrosarcoma, 1 malignant fibrous histiocytoma and 1 malignant giant cell tumor. Eleven patients had a resection of the proximal tibia and 2 had an extracapsular total knee resection with distal femur. Reconstruction of the defect was done in 8 cases with a custom-made Link Endo-Model Total Rotation Knee Joint Prosthesis, and in 5 with How Medica Modular Resection System (HMRS). We used two methods to reconstruct the ligamentum patellae. Fixation of the patellar tendon to the prosthesis only with suturing and/or stapling(group SS) was done in 7. Transposition of gastrocnemius muscle to enhance fixation and to cover the prosthesis(group TG) was done in 6. Regardless of fixation methods, total patellectomy was done in 5 either to lengthen the patellar tendon or to make primary skin closure easier or for both. In 8 cases, patella was left intact or resurfaced with polyethylene prosthesis. Active extension was measured while the patient was in a sitting position. There is no statistically meaningful difference in terms of extension deficit (Wilcoxon rank test, p=0.8800) between patellectomy group and intact patella group, and between group of fixation only with suturing and that of gastrocnemius transposition. Two cases of extension deficit over 30 degree were seen in group SS and in the group of intact patella. Conclusively, total patellectomy could be an option without increasing the risk of extension deficit when primary skin closure is difficult or patellar tendon is a little bit short to be fixed. There is no rating in the Enneking system of functional evaluation that this finding into consideration.

We investigated the effect of deep-freezed, boiled and autoclaved autogenous long bone graft on the incorporation of the radial diaphyseal reconstruction in 30 rabbits by radiogram and histology for 8 weeks. Immediate histologic changes of 1cm of resected long bone treated by deep freezing, boiling and autoclaving in each 2 rabbits were also observed as control. Resected, boiled ($95^{\circ}C$ for 5 min.) and reimplanted bone was compared with resected, autoclaved ($131^{\circ}C$ for 5 min.) and reimplanted bone, and resected, deep freezed with liquid nitrogen for 5 minutes and thawing in saline and reimplanted bone in the reconstruction of bilateral radial defects in each of 8, and in total 24 adult rabbits. The results were as follows : 1. Immediate histologic changes showed that intracortical osteocytes in lacunae were partially necrotized and the cortex were faintly stained with they Masson trichrome stain in both boiled and deep freezed groups, while they completely necrotized and their cortex stained more weakly with Masson trichrome stain in autoclaved group which means less amount of collagen and protein in cortex of long bone. 2. Radiographies at 8 weeks showed complete union with more marked incorporation and external callus formation in all boiled and freezed groups, whereas there was delayed union in four of sixteen (25%) in autoclaved group. Histologically, at 8 weeks after boiled and freezed, more intense incorporation with new bone formation and neovascularization were observed, whereas transverse clefts consisted with delayed union in 4 cases of autoclaved group (25%) were observed at osteotomy site. Through these studies, the boilod and deeply freezed bones acted as an osteoinductive material as well as osteoconductive, but the autoclaved bone only as osteoconductive. Though boilod and deeply freezed bone showed higher osteogenic potentials than autoclaved bone, the necrotizing effect on cortical and boiled bone was inferior to that of autoclaved. Thus the deeply freezed bone can be used for the treatment of aggressive benign or less malignant bone tumor not involving cortical bone, but the autoclaved bone supplemented with bone graft for the treatment of malignant bone tumor involving cortex of long bone.

Recent advances in imaging techniques, surgery and combination anti-cancer chemotherapy have brought high survival rates in osteosarcoma. To investigate the survival rate, local recurrence and complications in treatment, we analysed 25 osteosarcoma cases who had been treated with preoperative neo-adjuvant chemotherapy, surgery and post operative chemotherapy at Department of Orthopedic Surgery, Catholic University. From May 1988 to April 1995, 42 cases of stage IIB osteosarcoma were admitted in Department of Orthopedic Surgery. Among them, 17 cases who didn't follow our treatment guidance were excluded in this study. The average age were 19 years. There were 21 males and 4 females. The involved sites were 4 humerus, 10 femur, 10 tibia and 1 talus. Eleven cases had received intraarterial cisplatin and intravenous adriamycin chemotherapy, and 7 T-10 protocol and 7 intravenous ifosfamide, ADR, methotrexate, cisplatin. Twenty-three cases were treated with limb salvage surgery, and 2 amputation. The average follow-up was 35 months(3~82). There were 14 cases of continuous disease free, 9 cases of died of disease, 1 case of alive with disease, and 1 case of no evidence of disease at final follow-up. There were three cases of local recurrence at 6,8 and 12 months after operation. The estimated Kaplan-Meier's 5 year survival rates for all, ADR-cisplatin group, T-10 protocol group, and ifosfamide regimen group were 6%, 73%, 44% and 72%, respectively.

From January 1994 to August 1995 we performed 270 cases of fine needle aspiration cytology for bone and soft tissue lesions. Among them 137 cases were diagnosed histologically. Sixty-seven cases were benign and 70 cases were malignant. We analysed these on the aspect of sensitivity, specifity, positive predictive value, negative predictive value of the cytologic examination. Malignant cases consisted of bone tumor 29 cases; soft tissue tumor 25 cases; and metastatic tumor 16 cases. The sensitivity and specifity of the aspiration cytology for malignant tumor were 67.8% and 97%, respectively. The positive and negative predictive value of aspiration cytology were 97.4% and 72.7%, respectively. Among them 40 cases were primary bony lesions; 14 benign lesions, 26 malignamt bone tumors. Sensitivity of aspiration cytology for these primary bony lesion was 90%(18/20) and its specifity was 100%(13/13). Three cases showed atypical cells in cytology but with biopsy we could find them as one benign and two malignancies. Two cases of manignancy showed negative result in cytology; one was parosteal sarcoma of proximal femur and the other was osteosarcoma of proximal tibia which was biopsied already at other hospital. Although the overall sensitivity and specifity for malignant bone and soft tissue tumors were relatively low and not so predictable, the fine needle aspiration cytology for primary bony lesion was useful in the differential diagnosis of benign or malignancy.

The traditional methodology in Ewing's sarcoma was chemotherapy and radiotherapy. Recently surgery is reemerging as an important therapeutic tool and some paper report increased survival with it. The purpose of this nonrandomized study is to evaluate our result of Ewing's sarcoma with surgery, retrospectively. We experienced 30 cases for seven years and among them 6 were extraskeletal. In location, axial was 10 cases and peripheral was 20. By Enneking's classification, state IIB was 26 cases and IIIB was 4. Eighteen patients took operation, chemotherapy and/or radiotherapy, and remaining twelve took chemotherapy and/or radiotherapy only. Type of operation was limb salvage in 16 cases and amputation 2. Average dosage of radiation was 45.1Gy. Six kinds of chemotherapeutic regimen were used, but among them main protocols were Ifosfamide-Adriamycin(17 cases) and IESS(Cytoxan, Adriamycin, Methotrexate, Vincristine:8 cases). Complications were as follows. In operation group, there were 3 local recurrence and one case of nonunion. In nonoperated group, one local recurrence and one pancytopenia resulting in death. Average follow up was 29.7 months. Kaplan-Meier's ten year actuarial survival rate for the whole 30 cases was 26.8%. Significant difference in survival exists between central and peripheral lesions(p=0.05, by log rank test). Types of chemotherapy and surgery itself showed no significance. But surgery is important in function and local control. More intensive chemotherapeutic regimen to prevent distant metastasis and combined surgery and radiotherapy may be needed in Ewing's sarcoma.

Synovial sarcoma is an uncommon malignant soft tissue tumor which usually occurs in young-aged person, and frequently involves the lower extremities. Many authors recommended wide excision, adjuvant chemotherapy and radiation therapy. The proposed factors that affect the prognosis are age, size of tumor, site of tumor in the body, depth of tumor, histologic grade and method of treatment. The purpose of the study is to analyze the factors that affect the 5-year survival rate. We retrospectively evaluated 19 cases of synovial sarcoma treated in the Kosin University Medical Center from Jan. 1982 to Dec. 1994. The overall 5-year survival rate was 47.6% and the 5-year survival rates were significantly higher(P<0.05) in the group with smaller size of mass. The significantly lower 5-year survival rates were observed in the patient with deeply located lesion and with higher histologic grade. The 5-year survival rates were higher in the patients treated with wide excision than in the patients treated with amputation. But there was no significant difference between these groups. The adjuvant chemotherapy and radiotherapy were performed. In conclusion, we suggest that the better prognosis will be observed in the patients with smaller size of tumor mass, superficially located and lower histologic grade.

Liposarcoma is second in frequency only to malignant fibous histocytoma among the soft tissue sarcoma. Many different factors which might affect the survival rate of liposarcoma have been reported by many authors. The purpose of this study was to evaluate survival rate of liposarcoma and define the prognostic factors that affected survival rate. The authors analysed retrospectively 17 patients of liposarcoma in extremities from May 1984 to Dec. 1995 who had been treated in department of orthopaedic surgery of Kosin University Medical Center. All cases were resected with marginal or wide margin. There were 9 men and 8 women. The mean age was 48 years. The follow-up period ranged from 15 to 96 months. We compared the prognosis of the patients with several factors; age, sex, surgical staging, size, site, histologic type and treatment modality. At last follow-up, the presence of local recurrence was in 3 cases and the presence of lung metastasis was in 8 cases. The survival rates by Kaplan-Meier product limit method at 2 years and 5 years were 87% and 57% respectively. The statististically significant difference was estimated in histologic type, but was not estimated in age, sex surgical staging, size, site and treatment modality. In conclusion, the histologic type is considered as the most important factor of the prognosis in liposarcoma. Although it was too few patients for the differences to be statistically significant, we consider that surgical staging, site, size, the radio-therapy and chemothrapy in liposarcoma will affect the prognosis.

Giant cell tumor of tendon sheath is a slow-growing, unilateral and solitary lesion that is most commonly seen in the digits of the hand and knee, but occasionally occurs in the hips, ankles, toes and wrists. The lesion is asymptomatic or mildly painful, especially if it is diffuse and located in a major joint. The concepts concerning about the pathogenesis of these lesion have undergone constant revision, which include neoplastic process, inflammation and lipid metabolism. Authors analysized 20 patients with giant cell tumor of tendon sheath about the etiology, clinical findings, pathologic findings and treatment results. The results were as follows: 1. 13 cases were females (65%) and 7 cases were males (35%), and the range of age was from 9 years old to 60 years old. 2. The hand was most frequently involved site in which 14 cases (70%) were included, and the foot was involved in 5 cases (25%). 3. Solitary lesions were 15 cases and multiple lesions were 5 cases. 4. Radiographically, in 3 cases bony erosion was seen. 5. All cases were treated by surgical excision and presented no recurrence. In conclusion, the giant cell tumor of tendon sheath, which has been considered to be benign tumorous conditions appeared to be necessary for complete surgical excision to prevent recurrence.

Twenty-nine cases of unicameral bone cyst developed in long bone of children have been treated and followed up for 4.5 years in average form Department of Orthopaedic Surgery, Guro Hospital, Korea University, College of Medicine since September, 1983, Treatment for those lesions differed to form largely two groups, one of which consised of insillation of Methyl-prednisolone for non-weight bearing bones(12 humeri) and the other of curettage and autogenous bone graft for weight-bearing bones(7 femur). Methl-prednisolone group required repetition of instillation for 3.5 time in average spanning over 4 years until cloudy obliteration occurs. Curettage and bone graft had healed in 3 year 6 months' time in average. There were neither recurrence nor pathologic fractures of the lesions with the latter group. Immobilization period was virtually non with Methyl-prednisolone group and 4-6 weeks by hip spica with curettage and bone graft group. As conclusions, It seems confirmed that treatment strategy of unicameral bone cyst consisted of Methyl-prednisolone instillation for humerus lesions and early curettage and bone graft for femur lesions is applicable as guideline having solid ground in clinical experiences.

Metastaic bone tumors are usually accompanied with severe pain. The treatment modalities for this pain are so variable that patients are sometimes afraid of using them. Salmon calcitonin has a function to increase beta-endorphines followed by increasing the blood level of prostaglandin and thromboxan A2, which results in analgesic effect. This drug also has been known to decrease bone resorption. There were a few reports that parenteral use of salmon calcitonin decrease the pain from metastatic bone tumor. We wanted to know the effectiveness and tolerability of nasal spray of salmon calcitonin in relieving bone pain with metastatic tumor. We analyzed the effectiveness in the aspects of pain, sleep, performance status, mobility, supplementary analgesic use. The biologic effect of salmon calcitonin was analysed with CBC, Ca/P, BUN/Cr, uric acid. Simple radiography, alkaline phosphatase, osteocalcin, pyrilink-K were used as parameters for bone change. Eighteen cases of metastatic bone tumors took nasal spray of salmon calcitonin($Miacalcic^{(R)}$, 200IU/day) for 4 weeks, to relieve bone pain. With Wilcoxon Matched-Pairs Signed Ranks Test, we could find pain decreased significantly at 3 week and mobility become improved at 4 week of salmon calcitonin use. Other parameters didn't show any significant changes. We think the analgesic effect is mainly due to effect not on the local bone lesion but on the central nervous system, and that increased dose of salmon calcitonin can induce earlier and stronger analgesic effect.

The results of treatment of eighteen lesions of fibrous dysplasia which of them seventeen lesions were treated with surgery were reviewed at the Department of Orthopedic Surgery, College of Medicine, Hanyang University Hospital. We studied to evaluate the functional clinical results and the recurrence according to the type of disease, grafted bone, methods of treatment and location of lesion. We treated sixteen patients(five males and eleven females) and their mean age was 22.6 years. There was no association with skin pigmentation or dysfunction of endocrine system. Twelve patients had a monostotic pattern and four patients had a polyostotic pattern. Twelve lesions were treated with curettage and bone grafting and four lesions in the proximal femur were treated by internal fixation with curettage and bone grafting. One lesion was treated by en-bloc resection. There were eleven satisfactory results in twelve monostotic lesions and there were four satisfactory results in five polyostotic lesions, but the recurrence were four cases, respectively. The two unsatisfactory results were seen in two patients treated by autografting, but there were three recurrence of four lesions in autografting only, one of five in autografting and allografting, four of eight in allgrafting or xenografting. Four of six lesions in upper extremity were recurred after curettage and bone grafting and five of them showed satisfactory results. In pelvic and lower extremity lesions, the recurrence were occurred in two lesions after curettage and bone grafting and in two lesions after internal fixation and bone grafting. The recurrence does not always provide an unsatisfactory functional results and the recurrence showed higher rate in radiologic pattern of ground glass appearance with-out marginal sclerotic rim, but the recurrence according to grafted bone showed similar rates. Curettage and bone grafting is adequate for a symptomatic lesion and firm internal fixation is needed for a lesion in proximal femur. In use of grafted bone, xenograft or allograft may be preferable to autograft because of the disadvantage of autografting like a increased blood loss, prolonged operation times, etc.

Neurilemmomas are the most common benign tumor of the peripheral nerve trunks, and arises from the cells in the sheath of Schwann. Neurilemmomas are well encapsulated and may be separated easily from surrounding tissue and lie completely within a larger nerve trunk, with bundles of neurofibrils spread out over the surface of the tumor. A careful dissection and retraction of the nerve bundles will allow the tumor to be enucleated from the parent nerve without any significant interference with the function of the nerve. Resection of the involved nerve is seldom necessary and should be avoided if at all possible. Our aim in microscopic excision of neurilemmoma of extremities is to reduce any disturbance of the intact neurofibrils of the parent nerve. Thirteen cases of neurilimmomas were treated by microscopic excision at the Department of Orthopaedic Surgery, Korea University Hospital between January 1990 and March 1995. The results was as follows ; 1. The average age at surgical intervention was 40.1 years. Cases in fourth and fifth decades predominated. 2. In their anatomical distribution, 8 cases were in the upper extremity and 5 cases in the lower extremity. 11 cases were on the flexor surface. 3. On the operative field, all the tumors were well encapsulated, however 1 case of 13 was adherent to the periosteum of fibula. 4. In all cases, the tumor were enucleated from the parent nerve without any injury to nerve under high-power magnification, preserving individual fascicles, and sensory and motor function.

Ossifying fibroma is one of a group of fibro-osseous lesions which arises typically within the jaw bones and only rarely affects the long bones. Ossifying fibroma of the long bones almost involve exclusively the tibia but may also involve the fibula. Ossifying fibroma of the long bones is distinct from fibrous dysplasia, adamantinoma and nonossifying fibroma with regard to age of the patient, site, radiographic appearance, histological features, and clinical course. We are reporting the cases of seven patients with a tumor-like lesion that named osteofibrous dysplasia. It is most commonly found in the tibia and fibula of a child ten years of age or younger. Of the seven cases reported in this study, only one patient was younger than ten years. In all cases, the lesions were usually located in the tibial diaphysis. The average duration of clinical manifestation was 5.2 years. The clinical symptoms were anterior bowing of the tibia in 2 cases, buldging of the tibia in 2 cases, and mass overlying the tibia in 3 cases. On the roentgenography, it shows multiple radiolucent lesion with intervening sclerotic rim of the tibial diaphysis. In seven patients, 6 cases were confirmed with biopsy. We had done curettage and bone graft in three cases, VFG was done in one case. The other three cases underwent conservative management.

Prosthetic reconstruction of musculoskeletal defects about the knee for tumor has many advantages, particularly the maintenance of motion and immediate functional restoration. But, prosthetic reconstruction has inherent limitations in terms of long-term durability. The authors have reported here a patient who had mechanical failure at 61 months later following use of a modular resection system to reconstruct the segmental defect of proximal tibia in osteosarcoma. In this case, another technique of extensor mechanism reconstruction using Achilles tendon allograft was attempted. Because of the concerns involving durability of tumor prosthesis, increased emphasis has to be placed on innovation in prosthetic design.

A subungual exostosis is an uncommon benign osteochondral lesion that appears as a painful nodule. Histologically, the tumors consist of a proliferating fibrocartilaginous cap that merged into mature trabecular bone at its base. From 1989 through 1991, 5 patients with subungual exostosis were treated. Three of them had exostosis on the great toe. There were three girls and two boys. The average age of the patients was 10.6 years. All of patients were treated by local excision. Two cases of our patients treated with an incomplete excision were recurred within 3 months after the original procedure. Lack of awareness of unusual lesion can cause initial misdiagnosis in many cases. We considered that a complete excision of the lesion is important for preventing the recurrence, and it should be confirmed with intraoperative radiographs.

Benign osteoblastoma, a rare tumor which forms osteoid and woven bone, represents 3% of benign and 1% of all primary bone tumors. It can involve anywhere in the axial skeleton, which is most common in the spine (34%). But the lesion of the calcaneus is extremely rare. The ratio of males to females is 2:1, with 80 percent of the patients being under thirty years of age. Pain is the most common symptom and rarely pathologic fracture. Osteoblastoma is a benign tumor but has a high recurrence rate after intracapsular malignant change. Therefore, choice of surgical procedure is the 'enbloc' resection. Authors have experienced a case of osteoblastoma developed in calcaneus. The treatment was wide resection and triple arthrodesis. We have reported here the case in which osteoblastoma occured in calcaneus of the right foot.

The solitary osteochondroma is a hamartoma of the skeleton which derives from an aberrant subperiosteal germ of the fertile cartilage. Osteochondromas, which are uncommon in the hand can occur at the distal end of the proximal and middle phalanx away from the epiphyseal plate region. We experienced a rare case of solitary osteochondroma arising from distal end of fifth proximal phalanx of hand, and limiting the active motion of proximal interphalangeal joint. The patient was treated by marginal excision and tumor showed characteristic microscopic findings of osteochondroma.