Dynamic Posterior Instability Test: A New Test for Posterior Glenohumeral Instability.

Background: Recurrent posterior shoulder instability has become an increasingly recognized cause of shoulder disability, especially among athletes. The presentation can be vague and therefore its clinical diagnosis is often overlooked. Few diagnostic tests exist and these tests are difficult to perform in an anxious and apprehensive patient.

Ovariectomy-Induced Osteoporosis Does Not Impact Fusion Rates in a Recombinant Human Bone Morphogenetic Protein-2-Dependent Rat Posterolateral Arthrodesis Model.

Study Design Randomized, controlled animal study. Objective Recombinant human bone morphogenetic protein-2 (rhBMP-2) is frequently utilized as a bone graft substitute in spinal fusions to overcome the difficult healing environment in patients with osteoporosis. However, the effects of estrogen deficiency and poor bone quality on rhBMP-2 efficacy are unknown.

The effect of rhBMP-2 in a novel, non-instrumented extremity nonunion model.

Background: Pre-clinical models of bony nonunion typically employ critical-length defects. However, these models may not accurately reflect clinical practice since many nonunions are diagnosed without bone loss. We developed a non-displaced rat ulna fracture model in order to examine the efficacy of recombinant human bone morphogenetic protein-2 (rhBMP-2) with an absorbable collagen sponge (ACS) for nonunion treatment.

Effect of recombinant human bone morphogenetic protein-2 on a novel lung cancer spine metastasis model in rodents.

Lung cancer is the second most prevalent cancer. Spinal metastases are found in 30-90% of patients with death attributed to cancer. Due to bony destruction caused by metastases, surgical intervention is often required to restore spinal alignment and stability.

Ceramic-based bone grafts as a bone grafts extender for lumbar spine arthrodesis: a systematic review.

Study Design Systematic review. Objective Ceramic-based bone grafts have been widely utilized to reduce the need for iliac crest bone grafting given the complications associated with the harvest of iliac crest autograft. As a family, ceramics vary widely based on differences in composition, manufacturing, porosity, and structure, which may ultimately affect their efficacy.

Gel scaffolds of BMP-2-binding peptide amphiphile nanofibers for spinal arthrodesis.

Peptide amphiphile (PA) nanofibers formed by self-assembly can be customized for specific applications in regenerative medicine through the use of molecules that display bioactive signals on their surfaces. Here, the use of PA nanofibers with binding affinity for the bone promoting growth factor BMP-2 to create a gel scaffold for osteogenesis is reported. With the objective of reducing the amount of BMP-2 used clinically for successful arthrodesis in the spine, amounts of growth factor incorporated in the scaffolds that are 10 to 100 times lower than that those used clinically in collagen scaffolds are used.

A comparative evaluation of factors influencing osteoinductivity among scaffolds designed for bone regeneration.

Due to differing compositions, synthetic scaffolds developed for bone regeneration vary widely in efficacy. To quantify the impact of such differences on osteoinductivity, numerous parameters were examined. Absorbable collagen sponge (ACS), three ceramic-based carriers (#1-3) of varying compositions, mineralized allograft chips, and an experimental phosphoserine-rich nanofiber scaffold [S(P) gel] were compared in their ability to promote cell adhesion, proliferation/survival, growth factor binding/release, and osteogenic gene expression.

Ectonucleotide triphosphate diphosphohydrolase-1 (CD39) mediates resistance to occlusive arterial thrombus formation after vascular injury in mice.

Modulation of purinergic signaling, which is critical for vascular homeostasis and the response to vascular injury, is regulated by hydrolysis of proinflammatory ATP and/or ADP by ectonucleoside triphosphate diphosphohydrolase 1 (ENTPD-1; CD39) to AMP, which then is hydrolyzed by ecto-5'-nucleotidase (CD73) to adenosine. We report here that compared with littermate controls (wild type), transgenic mice expressing human ENTPDase-1 were resistant to the formation of an occlusive thrombus after FeCl(3)-induced carotid artery injury. Treatment of mice with the nonhydrolyzable ADP analog, adenosine-5'-0-(2-thiodiphosphate) trilithium salt, Ado-5'-PP[S], negated the protection from thrombosis, consistent with a role for ADP in platelet recruitment and thrombus formation.