Study on biocompatibility of carbon-based composites / 生物医学工程学杂志

Silicon carbide (SiC) film and silicon dioxide (SiO ) film were deposited on the surface of carbon/carbon composite (C/C) by low pressure chemical vapor deposition (LPCVD). The biocompatibility of the three carbon-based composites, e. g. C/C, C/C-SiC, C/C-SiO were investigated by cytotoxicity test, cell direct contact and cell adhesion experiments. Cytotoxicity, cell direct contact and cell adhesion showed that the three materials had no toxic effect on mouse fibroblasts (L929 cells). However, the particles dropped off from the three materials had a great impact on evaluation accuracy of the thiazolyl blue (MTT) test. More the particles were lost, more growth inhibition to L929 cells. The evaluation accuracy of MTT method can be kept with the filtered extract of materials. Furthermore, the results of surface particles shedding experiment showed that the amount of surface particles shed from C/C-SiO was the most, followed by C/C and C/C-SiC in 72 hours. Particles shedding curves showed there was a peak reached at eighth hour and then declined to the thirty-sixth hour. The filtrate analysis showed that there was no ion exchange between the three materials and simulated body fluid (SBF) solution. The results of this study on biocompatibility of carbon-based composites have certain guiding significance for their future application in clinical filed.

Therapeutic effect analysis for open resection in osteoid osteoma around lesser trochanter of femur / 中南大学学报(医学版)

To evaluate the radiological features of osteoid osteoma around lesser trochante of femur, and to analyze the outcomes of treatment with open surgery.
 Methods: From July 2013 to August 2015, 14 patients (9 males, 5 females) with osteoid osteoma around lesser trochanter were retrospectively reviewed. The ages of patients were 9-44 (average 20) years old. The duration of symptom was 3-36 (average 8) months. After the X-ray plain radiography, CT and MR, all patients underwent open resection. No intense exercise was allowed in the first three months after the operation.
 Results: There were 9 cases of cortical type, and 5 cases of subperiosteal type. The niduses were found by plain radiographs in 9 patients. By CT scan, the niduses were found in all 14 patients. The average pre-operative visual analogue scale (VAS) without NSAIDs was 6.5. One month after the operation, the average VAS was 0 for all patients. The follow up time for all patients was 9-34 (average 20) months. No recurrence, infection, neurovascular injury or fracture was found during the follow up.
 Conclusion: Open resection is a feasible method for osteoid osteoma around lesser trochanter of femur with satisfied outcome and low complication rate.

Efficacy of reconstruction with modular endoprosthesis after resection of periacetabular malignant tumors / 中南大学学报(医学版)

OBJECTIVE@#To explore the efficacy of the resection of periacetabular malignant tumors and the reconstruction with modular endoprosthesis.
@*METHODS@#From August 2006 to December 2012, 22 patients with periacetabular malignant tumors, who received the resection and reconstruction with modular prosthesis, were retrospectively reviewed. There were 11 males and 11 females, and the average age was 44 (16-65) years old. Pathological results showed there were 13 cases of chondrosarcoma, 5 cases of osteosarcoma, 2 cases of Ewing's sarcoma, 1 case of maligant fibrous histiocytoma, and 1 case of giant cell tumor. According to the classification system by Enneking, there were 11 cases of Type II+III resection, 5 cases of Type I+II+III resection, 3 cases of Type I+II resection, and 3 cases of Type II resection.
@*RESULTS@#All patients were followed up. The average time for follow-up was 49 (11-103) months. At the last time of follow-up, 13 patients (59%) were still alive, 9 patients (41%) died due to their primary disease. Metastasis occurred in 8 patients (36%), and local recurrence occurred in 5 patients (23%). The mean Musculoskeletal Tumor Society (MSTS) score for 13 cases of alive patients at the latest time of follow-up was (18.5±5.7) months. The mean score for 11 patients, whose limb salvage were successful, was 20.7±2.0.
@*CONCLUSION@#Reconstruction with modular prosthesis after wide resection for periacetabular malignant tumor can achieve satisfied outcome.

En bloc excision and reconstruction of the defect with pasteurized autograft for femoral primary malignant bone tumor in childen / 中南大学学报(医学版)

Objective:To evaluate the efficacy of femoral primary malignant bone tumors treated by limb salvage, with wide en bloc excision and reconstruction of the defect with recycled pasteurized autogratf. Methods: From January 2008 to January 2011, 11 patients (7 males, 4 females), aged (11.0±2.5) years suffering from femoral primary malignant bone tumors were treated with en bloc excision and reconstruction of the defect with recycled pasteurized autograft. Ten patients were histopathologically diagnosed with high-grade osteosarcoma, and 1 with Ewing’s sarcoma.According to the Enneking staging system, all patients were in Stage IIb. Results:All patients were followed-up for 24-65(42±20) months and all showed bony union at the last follow-up. hTe length of tumor bone resection was (17.5±3.2) cm, the operation time was (180±35) min, the intraoperative blood loss was (1200±250) mL, and drainage volume was (650±125) mL. Local skin necrosis occurred in 1 patient (9.1%), which was resolved by debridement. Nonunion occurred in 3 patients (27.3%), who were treated by secondary iliac crest cancellous bone gratfing.Pulmonary metastasis occurred in 1 patient (9.1%) who died 35 months post-operatively. According to the function assessment by the Enneking system, 5 patients had excellent results, 4 had good results, 1 fair and 1 poor results, with a satisfaction rate of 81.2%. Conclusion:A pasteurized autograft can be an easily accessible and economical alternative for children’s malignant bone tumor of femurs.

Salvage therapy by hemicortical excision and reconstruction for low-grade malignant bone tumour / 中南大学学报(医学版)

Objective: To treat low-grade limb malignant tumors with hemicortical excision and reconstruction of the defect with recycled pasteurized autogratf. Methods:From January 2005 to January 2011, 10 patients [age (27.0±6.5) years] suffering from low-grade limb malignant tumors were treated with hemicortical excision and reconstruction of the defect with recycled pasteurized autogratf:7 were histopathologically diagnosed as parosteal osteosarcoma, and 3 as peripheral chondrosarcoma. According to the Enneking staging system, 8 were in Stage IA and 2 were in IB. Results:All the patients were followed-up for (50±23) months. All the patients had bony union at the last follow-up. The length of tumor bone resection was (9.5±2.7) cm, operation time was (150±45) min, intraoperative blood loss was (1000±350) mL, and drainage volume was (450±200) mL. hTe only fracture in the host bone during the operation was treated by internal ifxation. Local recurrence occurred in 1 patient was treated by a wide operative margin and reconstruction with a prosthesis. There was no distal metastasis. A ccording to the Enneking system, 9 patients had excellent results and 1 had good results. Conclusion:Hemicortical excision for low-grade limb malignant tumors is safe and effective.

Medial head gastrocnemius muscle flap in the limb-salvage operation for proximal tibial osteosarcoma / 中南大学学报(医学版)

OBJECTIVE@#To evaluate the efficacy of transposition of the medial gastrocnemius muscle flap in the limb-salvage operation for proximal tibial osteosarcoma.@*METHODS@#From January 2000 to January 2010, 65 patients [37 males, 28 females; (17.0±6.5) years] suffering from the proximal tibial osteosarcoma had a limb-salvage operation. According to the Enneking staging system, 35 patients were in stage IIa, 30 in stage IIb. All of the patients underwent resection of the osteosarcomas and reconstruction of the bone defect by prothesis. Among them, there were 35 patients underwent the medial head of the gastrocnemius muscle flap transposition to reconstruct the soft tissues and the other 30 didn't.@*RESULTS@#All the patients were followed-up. In the group with the transposition of medial gastrocnemius muscle flap, the length of tumor bone resection was (13.5±4.2) cm, operation time was (150±45) min, intraoperative blood loss was (700±135) mL, and drainage volume was (500±200) mL. In the group without the transposition of medial gastrocnemius muscle flap, the length of tumor bone resection was (12.3±5.8) cm, operation time was (135±37) min, intraoperative blood loss was (600±105) mL, and drainage volume was (450±250) mL. There was significant difference in the operation time (P0.05). In the group with the transposition of medial gastrocnemius muscle flap, local skin necrosis occurred in 2 patients (5.7%), and prosthesis deep infection occurred in 1 (2.9%). In the group without the transposition of medial gastrocnemius muscle flap, subctaneous hematocele, and effusion occurred in 3 (10.0%), wound infection occurred in 4 (13.3%), 1 cured and the other 3 developed prosthesis deep infection.There was significant difference in the rate of local complications (P<0.05). According to the function assessment by the Enneking system, in the group with the transposition of medial gastrocnemius muscle flap, 13 patients had excellent results, 17 had good results, 3 had fair results and 2 had poor results, with a satisfaction rate of 85.7%. In the group without the transposition of medial gastrocnemius muscle flap, 10 patients had excellent results, 12 had good results, 5 had fair results and 3 had poor results, with a satisfaction rate of 73.3%. There was significant difference in function assessment between the 2 groups (P<0.05).@*CONCLUSION@#The flap transposition of the medial head of the gastrocnemiusmuscle can reconstruct the soft tissue defect, decrease the local complication rate and improve the clinical outcomes of the limb-salvage for the proximal tibia osteosarcoma.