Image quality and radiation dose in spinal surgery: a comparison of three imaging systems in phantom.

Purpose: Using optimal settings for x-ray scans is crucial for obtaining three-dimensional images of high quality while keeping the patient dose low. Our work compares dose and image quality (IQ) of three intraoperative imaging systems [O-arm cone-beam computed tomography (CBCT), ClarifEye C-arm CBCT, and Airo computed tomography] used for spinal surgery.

Approach: Patients of 70, 90, and 110 kg were simulated with an anthropomorphic phantom by adding tissue-equivalent material.

Percutaneous thoraco-lumbar-sacral pedicle screw placement accuracy results from a multi-center, prospective clinical study using a skin marker-based optical navigation system.

Study Design: Prospective multi-center study.

Objective: The study aimed to evaluate the accuracy of pedicle screw placement using a skin marker-based optical surgical navigation system for minimal invasive thoraco-lumbar-sacral pedicle screw placement.

Methods: The study was performed in a hybrid Operating Room with a video camera-based navigation system integrated in the imaging hardware.

Minimally Invasive Transforaminal Lumbar Interbody Fusion Using Augmented Reality Surgical Navigation for Percutaneous Pedicle Screw Placement.

Study Design: This was a retrospective observational study.

Objective: The aim of this study was to evaluate the accuracy of percutaneous pedicle screw placement using augmented reality surgical navigation during minimally invasive transforaminal lumbar interbody fusion (TLIF).

Summary Of Background Data: Augmented reality-based navigation is a new type of computer-assisted navigation where video cameras are used instead of infrared cameras to track the operated patients and surgical instruments.

Accuracy of augmented reality surgical navigation for minimally invasive pedicle screw insertion in the thoracic and lumbar spine with a new tracking device.

Background Context: Minimally invasive approaches are increasingly used in spine surgery. The purpose of navigation systems is to guide the surgeon and to reduce intraoperative x-ray exposure.

Purpose: This study aimed to determine the feasibility and clinical accuracy of a navigation technology based on augmented reality surgical navigation (ARSN) for minimally invasive thoracic and lumbar pedicle screw instrumentation compared with standard fluoroscopy-guided minimally invasive technique.

Fabrication of polycaprolactone-silanated β-tricalcium phosphate-heparan sulfate scaffolds for spinal fusion applications.

Background Context: Interbody spinal fusion relies on the use of external fixation and the placement of a fusion cage filled with graft materials (scaffolds) without regard for their mechanical performance. Stability at the fusion site is instead reliant on fixation hardware combined with a selected cage. Ideally, scaffolds placed into the cage should both support the formation of new bone and contribute to the mechanical stability at the fusion site.

Suppression of the immune system as a critical step for bone formation from allogeneic osteoprogenitors implanted in rats.

The surface marker profile of mesenchymal stromal cells (MSCs) suggests that they can escape detection by the immune system of an allogeneic host. This could be an optimal strategy for bone regeneration applications, where off-the-shelf cells could be implanted to heal bone defects. However, it is unknown how pre-differentiation of MSCs to an osteogenic lineage, a means of improving bone formation, affects their immunogenicity.

Inflammatory response and bone healing capacity of two porous calcium phosphate ceramics in critical size cortical bone defects.

In the present study, two open porous calcium phosphate ceramics, β-tricalcium phosphate (β-TCP), and hydroxyapatite (HA) were compared in a critical-sized femoral defect in rats. Previous comparisons of these two ceramics showed significantly greater osteoinductive potential of β-TCP upon intramuscular implantation and a better performance in a spinal fusion model in dogs. Results of the current study also showed significantly more bone formation in defects grafted with β-TCP compared to HA; however, both the ceramics were not capable of increasing bone formation to such extend that it bridges the defect.

Engineering new bone via a minimally invasive route using human bone marrow-derived stromal cell aggregates, microceramic particles, and human platelet-rich plasma gel.

There is a rise in the popularity of arthroscopic procedures in orthopedics. However, the majority of cell-based bone tissue-engineered constructs (TECs) rely on solid preformed scaffolding materials, which require large incisions and extensive dissections for placement at the defect site. Thus, they are not suitable for minimally invasive techniques.

The effect of platelet lysate supplementation of a dextran-based hydrogel on cartilage formation.

In situ gelating dextran-tyramine (Dex-TA) injectable hydrogels have previously shown promising features for cartilage repair. Yet, despite suitable mechanical properties, this system lacks intrinsic biological signals. In contrast, platelet lysate-derived hydrogels are rich in growth factors and anti-inflammatory cytokines, but mechanically unstable.

Streamlining the generation of an osteogenic graft by 3D culture of unprocessed bone marrow on ceramic scaffolds.

Mesenchymal stromal cells are present in very low numbers in the bone marrow, necessitating their selective expansion on tissue culture plastic prior to their use in tissue-engineering applications. MSC expansion is laborious, time consuming, unphysiological and not economical, thus calling for automated bioreactor-based strategies. We and others have shown that osteogenic grafts can be cultured in bioreactors by seeding either 2D-expanded cells or by direct seeding of the mononuclear fraction of bone marrow.

Clinical application of human mesenchymal stromal cells for bone tissue engineering.

The gold standard in the repair of bony defects is autologous bone grafting, even though it has drawbacks in terms of availability and morbidity at the harvesting site. Bone-tissue engineering, in which osteogenic cells and scaffolds are combined, is considered as a potential bone graft substitute strategy. Proof-of-principle for bone tissue engineering using mesenchymal stromal cells (MSCs) has been demonstrated in various animal models.