Bernese Periacetabular Osteotomy in a Hip Extra-Articular Resection Followed by Reconstruction Using an Extracorporeal Irradiated Acetabulum Autograft with Megaprosthesis, for Proximal Femur Osteosarcoma in a Pediatric Patient

Pelvic Chondrosarcoma Treated by En Bloc Resection with Patient-Specific Osteotomy Guides and Reimplantation of the Extracorporeally Irradiated Bone as an Osseocartilaginous Structural Orthotopic Autograft: A Report of Two Cases with Description of the Surgical Technique

Primary tumors of the pelvis are considered difficult to treat due to the complex anatomy and the proximity of important neurovascular structures. The surgical armamentarium for the treatment of these tumors has evolved with the help of cutting-edge technology from debilitating hemipelvectomies to solutions such as precise resections guided by patient-specific instruments or computer navigation and reconstruction by modular prostheses, 3D-printed custom-made implants, or orthotopic autograft reimplantation after extracorporeal irradiation. Different combinations of these techniques have been described in the literature with various rates of success. We present two cases of pelvic chondrosarcomas successfully treated by a combination of periacetabular resection with patient-specific osteotomy guides and orthotopic reimplantation of the extracorporeally irradiated autograft resulting in retention of the native hip.

Extra-Articular Hip Resection and Reconstruction with Custom Acetabular Resection Guide and Implants in a Case of High-Grade Spindle Cell Sarcoma of the Proximal Femur: A Case Report

CASE

A 29-year-old man was admitted with acute atraumatic left hip pain and inability to bear weight. Subsequent workup revealed an intracapsular pathologic fracture of the femoral neck secondary to a high-grade spindle cell sarcoma. A unique method of extra-articular resection and reconstruction using a 3-dimensional (3D)-printed custom cutting jig and a custom acetabular component was pursued. Wide margins were achieved without violating the joint capsule but preserving pelvic integrity, allowing a return to an active lifestyle.

CONCLUSION

Three-dimensional-printed custom resection guides and implants can help achieve adequate resection margins while preserving pelvic integrity and function.

Treatment of intra-articular hip malignancy with extra-articular resection, preservation of the acetabular columns, and total hip arthroplasty

Intra-articular malignant lesions of the hip present significant challenges. Resection often requires large resection of the acetabular bone and pelvic columns. Concurrent reconstruction options after intra-articular hip tumors are challenging and may necessitate the use of techniques and implants with uncertain long-term survivorship. We present a case of an intra-articular hip malignancy with extra-articular resection and preservation of the acetabular columns with reconstruction using a cementless acetabular shell fixed with screws.

MiR-30a regulates the proliferation, migration, and invasion of human osteosarcoma by targeting Runx2

Osteosarcoma (OS) is the most common primary malignant bone tumor in young patients. However, treatment paradigms and survival rates have not improved in decades. MicroRNAs have been shown to be critical regulators of physiological homeostasis and pathological process, including bone disease. Nearly half of the microRNA (miRNA) genes are located at genomic regions and fragile sites known to be frequently deleted or amplified in various kinds of cancers. In this study, we investigated the role miR-30a in OS. A negative correlation between miR-30a expression and malignant grade was observed in OS cell lines. The overexpression of miR-30a reduced proliferation, migration, and invasion in 143B cells and the inhibitor of miR-30a increased proliferation, migration, and invasion in Saos2 cells. Further studies revealed that runt-related transcription factors 2 (Runx2) was a regulative target gene of miR-30a. Rescue assay significantly reversed the effects of overexpressing or inhibiting miR-30a. miR-30a also suppressed tumor formation and pulmonary metastasis in vivo. All the results suggest a critical role of miR-30a in suppressing proliferation, migration, and invasion of OS by targeting Runx2.