Histopathology of fibro-osseous and cystic tumors of bone

Individualized 3D printing-assisted repair and reconstruction of neoplastic bone defects at irregular bone sites: exploration and practice in the treatment of scapular aneurysmal bone cysts

BACKGROUND

The irregular anatomical shape and complex structures of irregular bones make it more difficult to repair and reconstruct bone defects in irregular bones than in the long bones of the extremities. Three-dimensional (3D) printing technology can help to overcome the technical limitations of irregular bone repair by generating simulations that enable structural integration of the lesion area and bone structure of the donor site in all directions and at multiple angles. Thus, personalized and accurate treatment plans for restoring anatomical structure, muscle attachment points, and maximal function can be made. The present study aimed to investigate the ability of 3D printing technology to assist in the repair and reconstruction of scapular aneurysmal ABC defects.

METHODS

The study included seven patients with ABCs of the scapula. Based on computed tomography (CT) data for the patient, the scapula (including the defect) and pelvis were reconstructed using Mimics Medical software. The reconstructed scapula model was printed using a 3D printer. Before the operation, the model was used to design the surgical approach and simulate the operation process, to determine the length and radius of the plate and the number and direction of screws, and to determine the bone mass of the ilium and develop reasonable strategies for segmentation and distribution. The operation time, amount of bleeding, length and radius of the plate, and direction and number of screws were recorded.

RESULTS

The average duration of follow-up was 25.6 months, and none of the seven patients experienced recurrence during the follow-up period. The surgical approach, the length and radius of internal fixation, and the number and direction of screws were consistent with the designed operation plan. Patients gradually recovered the anatomical structure of the scapula and function of the shoulder joint.

CONCLUSIONS

In the treatment of bone defects caused by irregular bone tumors, 3D printing technology combined with surgery has the advantages of less trauma, short operation time, less bleeding and reducing the difficulty of operation, which can reduce the waste of bone graft, and more complete reconstruction of the anatomical structure of the defective bone.

Protuberant fibro-osseous lesion of the temporal bone: report of four cases and review of the literature

'Bullough lesions', also referred to as protuberant fibro-osseous lesions (PFOL), are rare temporal bone lesions initially described in 1999. Since only 12 cases have been reported, several key issues, such as their origin and recommended management strategies, remain unresolved. This article reports the largest cohort included in the literature to date, comprising four patients with PFOL. PFOL appears to be characterized by female and right-side predominance. These lesions were consistently located regarding the mastoid, generally diagnosed in early adulthood, without functional symptoms, and were always fibro-osseous. Invasive/malignant features were not found on imaging or histology. The main differential diagnosis was malignant low-grade parosteal osteosarcoma. Clinical examination and computed tomography images provided strong elements supporting the diagnosis of PFOL. Biopsy allowed molecular biology investigations (MDM2 and CDK4 amplification), in order to rule out low-grade parosteal osteosarcoma.