Resorption of deproteinized bovine bone mineral in a porcine calvaria augmentation model

Objectives: The original aim of the study was to determine the osteoconductive capacity of deproteinized bovine bone mineral (DBBM) of different particle sizes underneath acrylic hemispheres in vivo. However, the model failed and allowed us to report on the resorption of DBBM. Material and methods: Acrylic hemispheres were filled with and without a DBBM at a small particle size of 125–250 μm and at the regular particle size of 250–1000 μm. The hemispheres were positioned on the calvaria of eight minipigs. Histological and histomorphometric analysis was performed after 12 weeks. Results: We found that the acrylic hemispheres were displaced and a dense fibrous capsule sequestered the augmented area. Histology showed severe resorption activity and the presence of multinucleated cells on the surface of DBBM particles in areas adjacent to the fibrous capsule. Histomorphometric analysis revealed that only less than half of the originally augmented area, which was approximately 30 mm², remained after 12 weeks. The amount of residual DBBM (median 0.9 and 3.49 mm²) and bone (median 7.22 and 7.51 mm²) in the augmented area was similar in the small and the regular particle size group. Conclusion: The model represents a pathologic situation of excess resorption of DBBM and bone in an augmented area. The underlying cellular mechanisms remain to be uncovered. To cite this article:
Busenlechner D, Tangl S, Arnhart C, Redl H, Schuh C, Watzek G, Gruber R. Resorption of deproteinized bovine bone mineral in a porcine calvaria augmentation model.
Clin. Oral Impl. Res. 23 , 2012; 95–99.
doi: 10.1111/j.1600‐0501.2011.02198.x     

Patient perspectives on tobacco cessation services for persons living with HIV/AIDS

With the advent of highly active antiretroviral therapy, the survival for HIV-infected individuals has increased, but other health-related behaviors have been largely unaddressed. Tobacco use is of primary concern, given its prevalence and the medical implications of smoking among these patients. Improving responsiveness to the needs, values, and preferences of patients (i.e., patient-centeredness) is a focus for increasing participation in systems of care. To assess the social, cultural, and educational barriers limiting use of smoking cessation services by HIV-positive individuals, two focus groups were conducted at a Louisiana HIV outpatient clinic. Questions addressed smoking history, knowledge of and access to cessation services, and knowledge of effects of smoking on disease progression and medication efficacy. Identified themes included a desire for increased and more specific information on the health effects of smoking as related to the patients' HIV status, difficulty in quitting, motivation, and the increased burden of medication. These results provide recommendations for designing, for HIV-infected smokers, patient-centered treatment of tobacco use, including providing relevant knowledge, access to cessation services, and more effective messages related to the impact of tobacco use on disease progression.     

The time-averaged inflammatory disease activity estimates the progression of erosions in MRI of the sacroiliac joints in ankylosing spondylitis

A method to estimate the individual ankylosing spondylitis (AS) patient radiological progression of semi-quantitative magnetic resonance imaging (MRI) changes in the sacroiliac joints has not been described yet, which this study examines. Inflammatory disease activity and MRIs of the sacroiliac joints of 38 patients with recent onset established AS were analyzed at baseline and during follow-up. Sacroiliac MRIs were semi-quantitatively assessed using a modification of the "Spondylarthritis Research Consortium of Canada" (SPARCC) method. In each patient, the annual inflammatory disease activity was estimated by the time-averaged C-reactive protein (CRP; mg/l), calculated as the area under the curve. The mean (SD) CRP decreased from 1.3 (1.8) at baseline to 0.5 (0.6) at follow-up MRI (p < 0.04), which has been performed after a mean (SD) disease course of 2.8 (1.5) years. The mean (SD) annual increase (?) of SPARCC score from baseline to follow-up MRI was 0.4 (0.4). Baseline individual SPARCC sub-score for bone marrow edema did not statistically significantly correlate with individual ?SPARCC sub-score for erosions (p = N.S.). The individual AS patient correlation between annual time-averaged inflammatory disease activity and each annual ?SPARCC sub-scores was only statistically significant for erosions (p < 0.01; r = 0.71). Our results show that bone marrow edema and contrast-medium enhancement at baseline do not relate to the progression of erosions but the calculation of the individual patient annual time-averaged inflammatory disease activity allows to estimate the annual progression of erosions in sacroiliac MRIs of patients with AS.     

Ultrasound-guided versus computed tomography-controlled periradicular injections in the middle and lower cervical spine: a prospective randomized clinical trial

Purpose

We conducted this study to evaluate accuracy, time saving, radiation doses, safety, and pain relief of ultrasound (US)-guided periradicular injections versus computed tomography (CT)-controlled interventions in the cervical spine in a prospective randomized clinical trial.

Methods

Forty adult patients were consecutively enrolled and randomly assigned to either a US or a CT group. US-guided periradicular injections were performed on a standard ultrasound device using a broadband linear array transducer. By basically following the osseous landmarks for level definition in “in-plane techniques”, a spinal needle was advanced as near as possible to the intended, US-depicted nerve root. The respective needle tip positioning was then verified by CT. The control group underwent CT-guided injections, which were performed under standardized procedures using the CT-positioning laser function.

Results

The accuracy of US-guided interventions was 100 %. The mean time to final needle placement in the US group was 02:21 ± 01:43 min:s versus 10:33 ± 02:30 min:s in the CT group. The mean dose-length product radiation dose, including CT confirmation for study purposes only, was 25.1 ± 16.8 mGy cm for the US group and 132.5 ± 78.4 mGy cm for the CT group. Both groups showed the same significant visual analog scale decay (p < 0.05) without “inter-methodic” differences of pain relief (p > 0.05).

Conclusions

US-guided periradicular injections are accurate, result in a significant reduction of procedure expenditure under the avoidance of radiation and show the same therapeutic effect as CT-guided periradicular injections.     

Chondrocyte cultures from human proximal interphalangeal finger joints

Osteoarthritis (OA) of the hand is a common disease resulting in pain and impaired function. The pathogenesis of hand OA (HOA) is elusive and models to study it have not been described. Chondrocyte culture has been essential to understand cartilage degeneration, which is a hallmark of OA. We investigated the feasibility of human chondrocyte culture derived from proximal interphalangeal (PIP) finger joints. Hyaline cartilage of the PIP and knee joints was obtained from human cadavers. Chondrocytes harvested up to 236 h after death of the donors were viable and expressed chondrocyte‐specific genes. Gene expression comparing chondrocytes from PIP and knee joints using Affymetrix GeneChip arrays resulted in a unique PIP‐specific gene expression pattern. Genes involved in developmental processes including the WNT pathway were differentially expressed between the joints. These findings suggest that our knowledge on chondrocyte biology derived mainly from knee and hip joints may not apply to chondrocytes of the PIP joints and some of the distinctive features of HOA may be caused by the specific properties of PIP chondrocytes. Chondrocyte culture of PIP cartilage is a novel tool to study cartilage degeneration in HOA. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1569–1575, 2016.