ABSTRACT
Objective:To investigate the early and middle term clinical efficacies of 3D-printed metal prostheses in the reconstruction of bone defects after osteotomy in malignant bone tumors.Methods:A total of 34 patients with malignant bone tumors of lower extremity femur and tibia who underwent 3D printing individualized metal prosthesis replacement surgery in the Department of Bone and Soft Tissue of Affiliated Cancer Hospital of Zhengzhou University from March 2019 to March 2022 were retrospectively analyzed. There were 23 males and 11 females, with an average age of 19.1±15.2 years (range, 7-80 years). There were 22 children and adolescents younger than 18 years old. There were 3 cases in the proximal femur, 15 cases in the middle and distal femur, 10 cases in the proximal tibia and 6 cases in the distal tibia. According to the final pathological diagnosis, 24 cases of osteosarcoma, 6 cases of Ewing's sarcoma, 2 cases of undifferentiated sarcoma, 1 case of osteosarcoma, and 1 case of malignant giant cell tumor of bone were enrolled in this study. Postoperative complications, wound healing, periprosthetic fracture and aseptic loosening, tumor outcome (evaluated by tumor control evaluation criteria), and length difference of lower limbs were recorded. Response evaluation criteria in solid tumor (RECIST) was used to evaluate tumor outcomes. Prosthetic-bone interface healing was evaluated postoperatively, and the function was evaluated based on Musculoskeletal Oncology Society (MSTS) 93.Results:The length of lesions was 70-240 mm in 34 patients, with an average of 125.5±35.4 mm. The length of osteotomy was 80-275 mm, with an average of 160.2±33.9 mm. No tumor was found on the osteotomy surface. The customized prosthesis was firmly installed and closely matched with the side of the preserved articular surface. There were 2 patients with local incision fat liquefaction and 4 patients with superficial wound infection, which healed after debridement and antibiotic treatment. One distal tibia osteosarcoma case developed severe periprosthetic infection 2 months after surgery, resulting in prosthesis implantation failure, limb movement pain and poor ankle function. After removal of the prosthesis, infection control and osteogenesis with the Ilizarov technique, the infection was completely controlled and local osteogenesis was possible. The remaining 33 patients had a good prosthetic-bone interface union. One case was found to have localized bone resorption on the contact surface of the prosthesis 7 months after operation, but the metal prosthesis and screws were not loose. The incisions healed well in other patients, without infection, prosthesis loosening, fracture or other complications. All patients survived and were followed up for 13.8±5.6 months (range, 7-27 months). During the follow-up, there was no recurrence of tumor at the osteotomy end in all patients, but 5 patients developed lung metastasis. At the end of the last follow-up, all patients survived. Among them, 16 patients had unequal length of lower limbs, including 10 cases within 2 cm, 3 cases between 2-5 cm, and 3 cases over 5 cm. With the exception of one patient whose prosthesis was removed due to infection, the MSTS 93 of the other patients was 24.9±2.2 (range, 19-28), and were rated as excellent in 26 cases and good in 7 cases. According to the RECIST evaluation criteria, 26 of 34 patients had complete response, 5 had disease progression, and 3 had stable disease.Conclusion:3D printed metal prosthesis is one of the effective methods for the treatment of bone defects after resection of malignant bone tumors in lower limbs, which is safe, reliable and has satisfactory early curative effect.
ABSTRACT
Objective:To retrospectively analyze the clinical effects and complications of alcohol inactivation, irradiation inactivation, and liquid nitrogen inactivation in the treatment of femur osteosarcoma in children, in an attempt to provide a theoretical basis for clinical selection of in vitro inactivation methods of tumor bone segment. Methods:The clinical data of 93 children with femur osteosarcoma admitted to the Department of Bone and Soft Tissue, the Affi-liate Cancer Hospital of Zhengzhou University from January 2008 to December 2017 were retrospectively analyzed, and 40 children, including 21 males and 19 females, aged 8-18 (13.65±2.87) years, who were treated with in vitro inactivation and replantation of autogenous tumor bone segment, were screened.Among these children, there was alcohol inactivation in 15 cases, irradiation inactivation in 12 cases, and liquid nitrogen inactivation in 13 cases.A comparison was drawn on these 3 inactivation methods with respect to bone healing time, bone healing rate, tumor recurrence rate, infection rate, fracture or fixation failure rate, and revision rate. Results:All those 40 children were subject to valid medical followed-up, with the alcohol inactivation group for (102.60±16.55) months, the irradiation inactivation group for (59.33±6.39) months, and the liquid nitrogen inactivation for (36.85±6.49) months.The difference in follow-up time of 3 groups was statistically significant ( P<0.05). Compared with other 2 groups, the index of bone healing time, bone healing rate, infection rate and revision rate in the alcohol inactivation group were unfavorable, which showed a significant difference (all P<0.05); However, there was no significant difference in the recurrence rate, fracture rate or fixation failure rate compared with other 2 groups (all P>0.05); There was no significant difference in all above indexes between the irradiation group and the liquid nitrogen group (all P>0.05). Conclusions:Three in vitro inactivation methods for the treatment of tumor bone segment are safe and reliable.The alcohol inactivated bone has a long healing time and more complications.Both irradiation inactivation and liquid nitrogen inactivation are clinical options, but irradiation inactivation requires professional equipment, which may limit the clinical application.