Composite Hyaluronic Acid Gas-Entrapping Materials to Promote Wound Healing.

Tissue repair is often impaired in pathological states, highlighting the need for innovative wound-healing technologies. This study introduces composite hyaluronic acid gas-entrapping materials (GEMs) delivering carbon monoxide (CO) to promote wound healing in pigs. These composite materials facilitate burst release followed by sustained release of CO over 48 h.

A New Method for Creating Impact-Induced Intra-Articular Fractures in a Rabbit Model Induces Severe Post-Traumatic Osteoarthritis.

Objectives: The objective of this work was to develop a model of intra-articular fracture (IAF) in a rabbit and document the speed and severity of degenerative joint changes after fracture fixation.

Methods: With Institutional Animal Care & Use Committee approval, impact-induced IAFs were created in the distal tibia of 16 New Zealand White rabbits. Fractures were fixed with a plate and screws.

Intra-Articular Adeno-Associated Virus-Mediated Proteoglycan 4 Gene Therapy for Preventing Posttraumatic Osteoarthritis.

Lubricin, a glycoprotein encoded by the proteoglycan 4 (PRG4) gene, is an essential boundary lubricant that reduces friction between articular cartilage surfaces. The loss of lubricin subsequent to joint injury plays a role in the pathogenesis of posttraumatic osteoarthritis. In this study, we describe the development and evaluation of an adeno-associated virus (AAV)-based PRG4 gene therapy intended to restore lubricin in injured joints.

The Effect of Pulsed Electromagnetic Field and Combined Magnetic Field Exposure Time on Healing of a Rabbit Tibial Osteotomy.

Background: This study compares effectiveness of two commercially available signals, Pulsed Electromagnetic Field (PEMF) and Combined Magnetic Field (CMF) clinical signals, to stimulate bone healing in rabbit tibial osteotomies.

Methods: One millimeter osteotomies in New Zealand White rabbits, stabilized with external fixators, were exposed daily to either signal for 30 minutes, three or six hours. Osteotomized sham controls received no signal exposure.

Electrospun PLGA and β-TCP (Rebossis-85) in a Lapine Posterolateral Fusion Model.

Background: Calcium phosphate materials have been employed clinically as bone void fillers for several decades. These materials are most often provided in the form of small, porous granules that can be packed to fill the wide variety of size and shape of bony defects encountered. ReBOSSIS-85 (RB-85) is a synthetic bioresorbable bone void filler for the repair of bone defects with handling characteristics of glass wool-like (or cotton ball-like).

Targeting mitochondrial responses to intra-articular fracture to prevent posttraumatic osteoarthritis.

We tested whether inhibiting mechanically responsive articular chondrocyte mitochondria after severe traumatic injury and preventing oxidative damage represent a viable paradigm for posttraumatic osteoarthritis (PTOA) prevention. We used a porcine hock intra-articular fracture (IAF) model well suited to human-like surgical techniques and with excellent anatomic similarities to human ankles. After IAF, amobarbital or -acetylcysteine (NAC) was injected to inhibit chondrocyte electron transport or downstream oxidative stress, respectively.

Influence of 45S5 Bioactive Glass in A Standard Calcium Phosphate Collagen Bone Graft Substitute on the Posterolateral Fusion of Rabbit Spine.

Introduction: Spinal fusion surgery is an effective but costly treatment for select spinal pathology. Historically iliac crest bone graft (ICBG) has remained the gold standard for achieving successful arthrodesis. Given well-established morbidity autograft harvest, multiple bone graft replacements, void fillers, and extenders have been developed.

Comparison of Two Synthetic Bone Graft Products in a Rabbit Posterolateral Fusion Model.

Background: The drawbacks of iliac crest autograft as graft material for spine fusion are well reported. Despite continued modifications to improve bone healing capacity, the efficacy of synthetic graft materials as stand-alone replacements remains uncertain. The rabbit posterolateral fusion model is an established environment for testing of fusion concepts.

Assessment of SiCaP-30 in a Rabbit Posterolateral Fusion Model with Concurrent Chemotherapy.

Chemotherapy derivatives of the rabbit posterolateral fusion model are considered a challenging environment in which to test bone graft materials. The purpose of this study was to determine the performance characteristics of SiCaP-30 as a bone graft substitute relative to autograft (iliac crest bone graft [ICBG]), Actifuse ABX and β-Tricalcium Phosphate-Bioactive Glass-Type I Collagen (βTCP-BG) in a rabbit posterolateral spine fusion model with concurrent chemotherapy treatment This was a randomized, controlled study in a laboratory setting with blinded assessment of fusion by manual palpation and flexibility testing. Sixty rabbits were entered into the study with 45 used for analysis.

Evaluation of a novel silicate substituted hydroxyapatite bone graft substitute in a rabbit posterolateral fusion model.

Study Design/setting: Randomized, controlled study in a laboratory setting. Blinded observations/assessment of study outcomes.

Objective: The purpose of this study is to determine the performance characteristics of a novel silicate-substituted hydroxyapatite bone graft substitute (BGS), SiCaP EP (Baxter Healthcare/ ApaTech, Elstree, UK), in a stand-alone mode, a stand-alone with bone marrow aspirate (BMA) mode, and an extender mode with iliac crest autograft (ICBG) in a rabbit posterolateral spine fusion model.

Assessment of Mastergraft(®) strip with bone marrow aspirate as a graft extender in a rabbit posterolateral fusion model.

Study Design/setting: Randomized, controlled study in a laboratory setting. Blinded observations/assessment of study outcomes.

Objective: The Purpose of this study is to determine the performance characteristics of Mastergraft(®) Strip with bone marrow aspirate (BMA) as a bone graft extender in a rabbit posterolateral spine fusion model.

Assessment of MASTERGRAFT PUTTY as a graft extender in a rabbit posterolateral fusion model.

Study Design: Randomized, controlled study in a laboratory setting. Blinded observations/assessment of study outcomes.

Objective: The purpose of this study was to determine the performance characteristics of MASTERGRAFT PUTTY as a bone graft extender in a rabbit posterolateral spine fusion model.

B2A peptide on ceramic granules enhance posterolateral spinal fusion in rabbits compared with autograft.

Study Design: Six groups of 10 animals underwent single level, uninstrumented posterolateral lumbar fusions. Graft sites were implanted with autologous bone, autologous bone plus B2A coated granules with concentrations of 0-, 50-, 100-, or 300 microg/mL, or no graft material. Explanted motion segments were analyzed by Faxitron radiographs, computerized tomography (CT), manual palpation, and histology.

Effects of direct current electrical stimulation on gene expression of osteopromotive factors in a posterolateral spinal fusion model.

Study Design: An in vivo model was used to determine levels of mRNA expression in response to direct current (DC) electrical stimulation in a rabbit posterolateral fusion model.

Objectives: This study tested the possibility that DC stimulation at the surgery site would increase expression of genes related to bone formation relative to expression in autograft alone.

Summary Of Background Data: DC electrical stimulation as an adjunct treatment in spinal surgery has shown increased fusion rates when compared with autograft alone, yet the biology of such treatment is not fully understood.

Cellular interactions and bone healing responses to a novel porous tricalcium phosphate bone graft material.

The use of a porous tricalcium phosphate bone void filler (Cellplex TCP, Wright Medical Technology, Inc, Arlington, Tenn) as an alternative to autograft in bone grafting was studied in benchtop, in vitro cell culture, and in vivo preclinical studies. The experimental design included material property quantification, scaffold seeding with mesenchymal stem cells, and implantation in a rabbit segmental defect model. Measured material properties denoted appropriate composition, porosity, and strengths as compared to the literature.