Comparison of Fixation Techniques for Acetabular Fractures Involving the Anterior Column with Disruption of the Quadrilateral Plate: A Biomechanical Study.

Background: In elderly patients who have sustained an acetabular fracture involving disruption of the quadrilateral plate (QLP), postoperative loading of the joint beyond the level of partial weight-bearing can result in medial redisplacement of the QLP. The purpose of this biomechanical study was to compare the performances of 4 different fixation constructs intended to prevent medial redisplacement of the QLP.

Methods: Anterior column posterior hemitransverse (ACPHT) fractures with disruption of the QLP were created on synthetic hemipelves (fourth-generation Sawbones models) and subsequently stabilized with (1) a 12-hole plate bridging the QLP (Group 1), (2) the plate with added periarticular screws along the QLP (Group 2), (3) the plate combined with an infrapectineal buttress plate (Group 3), or (4) the plate with the added periarticular screws as well as the buttress plate (Group 4).

Extracortical plate fixation with new plate inserts and cerclage wires for the treatment of periprosthetic hip fractures.

Purpose: Fixation of periprosthetic hip fractures with intracortical anchorage might not be feasible in cases with bulky implants and/or poor bone stock.

Methods: Rotational stability of new plate inserts with extracortical anchorage for cerclage fixation was measured and compared to the stability found using a standard technique in a biomechanical setup using a torsion testing machine. In a synthetic PUR bone model, transverse fractures were fixed distally using screws and proximally by wire cerclages attached to the plates using "new" (extracortical anchorage) or "standard" (intracortical anchorage) plate inserts.

Risk factors for aseptic loosening of Müller-type straight stems: a registry-based analysis of 828 consecutive cases with a minimum follow-up of 16 years.

Background and purpose Even small differences in design variables for the femoral stem may influence the outcome of a hip arthroplasty. We performed a risk factor analysis for aseptic loosening of 4 different versions of cemented Müller-type straight stems with special emphasis on design modifications (2 shapes, MSS or SL, and 2 materials, CoNiCrMo (Co) or Ti-6Al-7Nb (Ti)). Methods We investigated 828 total hip replacements, which were followed prospectively in our in-house register.

Printability of calcium phosphate powders for three-dimensional printing of tissue engineering scaffolds.

Three-dimensional printing (3DP) is a versatile method to produce scaffolds for tissue engineering. In 3DP the solid is created by the reaction of a liquid selectively sprayed onto a powder bed. Despite the importance of the powder properties, there has to date been a relatively poor understanding of the relation between the powder properties and the printing outcome.