Citations

ObjectivesThe bony shoulder stability ratio (BSSR) allows for quantification of the bony stabilisers in vivo. We aimed to biomechanically validate the BSSR, determine whether joint incongruence affects the stability ratio (SR) of a shoulder model, and determine the correct parameters (glenoid concavity versus humeral head radius) for calculation of the BSSR in vivo.MethodsFour polyethylene balls (radii: 19.1 mm to 38.1 mm) were used to mould four fitting sockets in four different depths (3.2 mm to 19.1mm). The SR was measured in biomechanical congruent and incongruent experimental series. The experimental SR of a congruent system was compared with the calculated SR based on the BSSR approach. Differences in SR between congruent and incongruent experimental conditions were quantified. Finally, the experimental SR was compared with either calculated SR based on the socket concavity or plastic ball radius.ResultsThe experimental SR is comparable with the calculated SR (mean difference 10%, sd 8%; relative values). The experimental incongruence study observed almost no differences (2%, sd 2%). The calculated SR on the basis of the socket concavity radius is superior in predicting the experimental SR (mean difference 10%, sd 9%) compared with the calculated SR based on the plastic ball radius (mean difference 42%, sd 55%).ConclusionThe present biomechanical investigation confirmed the validity of the BSSR. Incongruence has no significant effect on the SR of a shoulder model. In the event of an incongruent system, the calculation of the BSSR on the basis of the glenoid concavity radius is recommended. Cite this article: L. Ernstbrunner, J-D. Werthel, T. Hatta, A. R. Thoreson, H. Resch, K-N. An, P. Moroder. Biomechanical analysis of the effect of congruence, depth and radius on the stability ratio of a simplistic ‘ball-and-socket’ joint model. Bone Joint Res 2016;5:453–460. DOI: 10.1302/2046-3758.510.BJR-2016-0078.R1.

SummaryBackgroundReal‐world comparative benefits and risks of infliximab (IFX) and adalimumab (ADA) in patients with ulcerative colitis (UC) are unclear.AimTo evaluate the comparative effectiveness and safety of IFX and ADA in patients with UC who were new users of anti‐TNF agents.MethodsUsing an administrative claims database (Optum Labs Data Warehouse), we identified patients who received first anti‐TNF (IFX, ADA) prescription after a 12‐month period without any anti‐TNF treatment (baseline), and with a minimum 6‐month follow‐up after anti‐TNF initiation. Primary outcome measures were: all‐cause and UC‐related hospitalisation, abdominal surgery, corticosteroid use >60 days after starting anti‐TNF, and serious infections. We performed 2:1 propensity‐score matched Cox proportional hazard analysis, and inverse probability‐of‐treatment weight (IPTW) analysis, accounting for healthcare utilisation, comorbidities and use of UC‐related medication.ResultsWe included 1400 new users of anti‐TNF agents (age, 43 ± 15 years; 52% males), from 2006 to 2014. On propensity‐score matched analysis, there was no significant difference in the risk of UC‐related hospitalisation [IFX vs. ADA; adjusted hazard ratio (aHR), 1.04; 95% confidence interval (CI) 0.71–1.51], corticosteroid use (aHR, 0.85; 95% CI, 0.68–1.06) and serious infections (aHR, 0.62; 95% CI, 0.29–1.34) between IFX‐ and ADA‐treated patients; the number of surgical events was very small. On IPTW analysis, risk of corticosteroid use was significantly lower in IFX – as compared to ADA – treated patients (aHR, 0.82; 95% CI, 0.68–0.99). Results were stable on multiple sensitivity analyses.ConclusionsIn a large retrospective cohort of patients with UC who were new users of anti‐TNF agents, IFX‐treated patients may have lower corticosteroid use than ADA‐treated patients, but risk of hospitalisation and serious infections were comparable.

Each of eight mongrel dogs received a 0.5 ml injection of polytef paste into the right vocal fold. These dogs were killed at 1 week, 1 month, 3 months, and 6 months after injection, and a number of organs were examined. Polarizing microscopy was used to examine the upper cervical lymph nodes, lower cervical lymph nodes, mediastinal lymph nodes, abdominal lymph nodes, cerebral cortex, brainstem, lung, liver, spleen, and kidney to determine if migration of polytef had occurred. Examination of these organs revealed that there was consistent migration of polytef particles into the cervical lymph nodes, with the highest incidence occurring in upper cervical lymph nodes on the side of injection. There was no evidence of migration of polytef particles to distant sites. The study shows that polytef particles may migrate to cervical lymph nodes after injection into the larynx; however, there is no evidence of distant migration.

Extraskeletal Ewing's sarcoma is a rare malignant neoplasm. Arising from a primitive mesenchymal stem cell and primarily affecting young adults, this lesion demands aggressive therapy, including surgical treatment, radiation therapy, and chemotherapy.