Long-term Follow-up of the Use of a Synthetic Bone Graft Composite in the Surgical Management of Primary Bone Tumors

Low rate of healing and high incidence of complications in benign pediatric bone tumors treated with synthetic calcium sulfate-calcium phosphate bone graft

Background

Synthetic calcium sulfate-calcium phosphate bioceramic composite has been developed as a material for bone grafting; however, the literature is limited on outcomes of benign bone tumors treated with bone grafting. This study aims to investigate the outcomes of benign pediatric bone tumors treated with a calcium sulfate-calcium phosphate composite bone graft.

Methods

A retrospective review at a tertiary pediatric hospital with benign bone tumors treated with curettage and bone grafting with a calcium sulfate-calcium phosphate synthetic bone graft from 2008-2018 was included. Minimum follow-up was 6 months.

Results

Twenty-seven patients met inclusion criteria with a mean age of 10.3 ± 4.5 years and follow-up was 37.2 ± 22.3 months. Diagnoses were unicameral bone cysts (n = 16) and aneurysmal bone cysts (n = 11). Pathologic fracture was present in 48% (13/27) of patients on admission. All patients were treated using synthetic bone grafts and 37% (10/27) with internal fixation. Following index treatment, 96% (26/27) had resolution of pain and returned to full activity at 13.4 ± 10.7 weeks. Complications occurred in 33% (9/27) of patients; one developed chronic hip pain resulting in decreased physical activity, seven had a tumor recurrence without fracture, and one had tumor recurrence with pathologic fracture. Revision surgery was required in 26% (7/27) of cases. Per the modified Neer outcomes rating system, 52% of patients had a healed bone lesion, 4% had a healing lesion with a bone defect, and 44% had a persistent/recurrent cyst.

Conclusions

Children with benign bone tumors treated with curettage and bone grafting using a calcium sulfate-calcium phosphate composite had a high incidence of complications and revision surgery.

Level of evidence

IV.

Advances in copper-containing biomaterials for managing bone-related diseases

Bone-related diseases pose a major challenge in contemporary society, with significant implications for both health and economy. Copper, a vital trace metal in the human body, facilitates a wide range of physiological processes by being crucial for the function of proteins and enzymes. Numerous studies have validated copper's role in bone regeneration and protection, particularly in the development and expansion of bone collagen. Owing to copper's numerous biological advantages, an increasing number of scientists are endeavoring to fabricate novel, multifunctional copper-containing biomaterials as an effective treatment strategy for bone disorders. This review integrates the current understanding regarding the biological functions of copper from the molecular and cellular levels, highlighting its potential for bone regeneration and protection. It also reviews the novel fabrication techniques for developing copper-containing biomaterials, including copper-modified metals, calcium phosphate bioceramics, bioactive glasses, bone cements, hydrogels and biocomposites. The fabrication strategies and various applications of these biomaterials in addressing conditions such as fractures, bone tumors, osteomyelitis, osteoporosis, osteoarthritis and osteonecrosis are carefully elaborated. Moreover, the long-term safety and toxicity assessments of these biomaterials are also presented. Finally, the review addresses current challenges and future prospects, in particular the regulatory challenges and safety issues faced in clinical implementation, with the aim of guiding the strategic design of multifunctional copper-based biomaterials to effectively manage bone-related diseases.

Benign Bone Tumors Beyond Osteoid Osteoma: Percutaneous Minimally Invasive Image-Guided Interventions

Painful benign bone tumors often adversely influence quality of life primarily due to skeletal-related events such as unremittable pain, pathologic fracture, neurologic deficit, as well as skeletal growth disturbance. Substantial advances in percutaneous minimally invasive interventions for treatment of painful benign bone tumors beyond osteoid osteoma have been established as safe, efficacious, and durable treatments to achieve definitive cure. This article details the available armamentarium and most recent advances in minimally invasive percutaneous interventions and the role of radiologists for the management of patients with benign bone tumors beyond osteoid osteoma.

Utility of 45S5 Bioactive Glass As Bone Graft Substitute for Cavitary Defects in Pediatric Bone Tumors: A Preliminary Study

BACKGROUND

Bioactive glass has become an increasingly used treatment of cavitary bone defects in a number of orthopaedic applications. The purpose of this study was to evaluate the clinical and radiographic outcomes of bioactive glass used for benign cavitary pediatric bone tumors. A specific focus was on radiographic filling of defects and occurrence of complications by tumor class.

METHODS

A single institution retrospective study was performed, which entailed review of the clinical and radiographic data of 21 patients who underwent surgical curettage and grafting of benign or low-grade malignant bone tumors from 2018 to 2020. In all the cases, 45S5 bioactive glass (Fibergraft; Prosidyan, New Providence, NJ) was used to fill the bone defects. For each patient, data on demographic, preoperative diagnosis, defect size, time to mobilization, radiographic filling grade, pain, and complications were obtained. The Wilcoxon-Mann-Whitney test and Kaplan-Meier survival analysis were used for comparisons between tumor classes.

RESULTS

In the 21 patients, 11 bone tumors were latent or active (class 1) and 10 were aggressive (class 2). The mean age was 13.0±3.7 years, 6 (28.6%) were female, and the median and interquartile range for initial tumor size were 18.8 (5.8 to 50.6) cm 3 . Tumors that were class 2 had significantly more complications with bioactive glass use compared with class 1 tumors [0 vs. 1 (0 to 1), P =0.040]. The time of persistent fill grade 1 or 2 defects up to final follow-up was less in class 1 versus class 2 lesions ( P =0.048).

CONCLUSIONS

Bioactive glass agents have utility for treating a broad variety of pediatric bone tumors after curettage. However, focusing these agents' use in treating latent or active subtypes of bone tumors may be ideal in minimizing complications and time to higher fill grade.

LEVEL OF EVIDENCE

Level III - Therapeutic.

Imaging following surgery for primary appendicular bone tumours

Primary bone tumours are uncommon, with sarcomas accounting for < 0.2% of all malignancies. The survival rate of primary bone sarcomas has significantly improved due to (neo)adjuvant therapy, while improved surgical techniques and development of new prostheses have shifted the surgical focus from amputation to limb preservation in the vast majority of patients. A wide variety of surgical options are available for the treatment of primary bone tumours which depend upon histological diagnosis, their appearance at the time of presentation and response to any (neo)adjuvant therapy as required. This review is intended to help radiologists familiarise themselves with the management of primary appendicular bone tumours and expected normal postoperative appearances for the various surgical techniques, and to recognise potential complications.

Improved osteogenesis and angiogenesis of a novel copper ions doped calcium phosphate cement

Improving the angio1genesis potential of bone-repairing materials is vital for the repair of cancerous bone defects. It can further facilitate the delivery of active substances with osteogenesis and anti-tumor functions, ultimately promoting the formation of new bone tissues. Copper ions (Cu²⁺) have been proved to be beneficial to angiogenesis. This study developed a new type of Cu-containing calcium phosphate cement (Cu-CPC) by incorporating with copper phosphate (CuP) nanoparticles with a photothermal anti-tumor effect. The results revealed that the main phases of all hydrated CPCs were hydroxyapatite, unreacted tricalcium phosphate and calcium carbonate. But the hydration products of CPC became thinner after the incorporation of Cu²⁺. With the increase of CuP concentration, the setting time of CPC was prolonged while the injectability and the compressive strength were increased. The release concentration of Cu²⁺in vitro was among 0.01 to 0.74 mg/mL, which showed a positive relation with CuP content. Mouse bone marrow stromal cells (mBMSCs) displayed higher adhesion activity, proliferation performance and expression of osteogenic genes and proteins on CPC with 0.01 wt% CuP (0.01Cu-CPC) and 0.05 wt% CuP (0.05Cu-CPC). When human umbilical vein endothelial cells were co-cultured with 0.01Cu-CPC and 0.05Cu-CPC extracts, the proliferation and angiogenesis-related gene and protein expression were significantly increased, and the in vitro tube formation capacity was promoted. However, higher CuP content inhibited the proliferation of mBMSCs. In conclusion, CPC with 0.01 wt% and 0.05 wt% CuP nanoparticles has the potential to promote bone formation around cancerous bone defects, which would be promising for bone regeneration and treatment of bone tumors.