Reciprocal Alterations in Osteoprogenitor and Immune Cell Populations in Rheumatoid Synovia.

Rheumatoid arthritis (RA) is chronic, autoimmune joint inflammation characterized by irreversible joint destruction. Besides increased resorption, destruction is a result of decreased bone formation, due to suppressed differentiation and function of the mesenchymal lineage-derived osteoblasts in inflammatory milieu. In this study, we analyzed the cellular composition of synovial tissue from 11 RA and 10 control patients harvested during planned surgeries in order to characterize resident synovial progenitor populations.

Measurement of safe acetabular medial wall defect size in revision hip arthroplasty with a porous cup.

Introduction: The majority of acetabular revisions can be performed with an uncemented, porous acetabular component with or without bone grafting. These are contained acetabular defects, with an intact acetabular rim (Paprosky type I and II). As defects of the medial wall of the acetabulum are a challenge situation revision surgery, we performed this biomechanical study on a pig pelvis model with contained acetabular defects to determine the size of medial wall defect at which the acetabular cup will have sufficient primary stability.

Revision of Acetabular Component with a Debonded Porous Coating in an Elderly Patient.

Debonding of the porous coating from the acetabular component of a total hip endoprosthesis is a rare complication. Revision total hip arthroplasty for an unstable acetabular component with a debonded porous coating strongly fixed to the bone can be challenging, especially in elderly patients of poor overall health. In such patients, revision procedures should be as simple and safe as possible.