Shell design and reaming technique affect deformation in mobile-bearing total hip arthroplasty acetabular components.

Press-fit acetabular components are susceptible to rim deformation. The inherent variability within acetabular reaming techniques may generate increased press-fit and, subsequently, additional component deformation. The purpose of this study was to analyze the insertion and deformation characteristics of acetabular components designed for dual-mobility systems based on component design, size, and reaming technique.

High initial stability in porous titanium acetabular cups: a biomechanical study.

Initial stability with limited micromotion in uncemented total hip arthroplasty acetabular components is essential for bony attachment and long-term biomechanical fixation. This study compared porous titanium fixation surfaces to clinically established, plasma-sprayed designs in terms of interface stability and required seating force. Porous plasma-sprayed modular and metal-on-metal (MOM) cups were compared to a modular, porous titanium designs.

Acetabular cup stiffness and implant orientation change acetabular loading patterns.

Acetabular cup orientation has been shown to influence dislocation, impingement, edge loading, contact stress, and polyethylene wear in total hip arthroplasty. Acetabular implant stiffness has been suggested as a factor in pelvic stress shielding and osseous integration. This study was designed to examine the combined effects of acetabular cup orientation and stiffness and on pelvic osseous loading.

Metal backing significantly decreases tibial strains in a medial unicompartmental knee arthroplasty model.

Clinical success of unicompartmental knee arthroplasty (UKA) is on the rise and is dependent on multiple patient, implant, and surgical factors. Tibial subsidence has been clinically reported as a cause of failure in UKA with an all-polyethylene tibial design in the absence of metal backing, yet the role of metal backing UKA tibial components on tibial loading is not fully understood. In this study, composite tibiae were implanted with medial all-polyethylene fixed-bearing or metal-backed UKA tibial components and a 1.

A comparison in proximal tibial strain between metal-backed and all-polyethylene anatomic graduated component total knee arthroplasty tibial components.

Loading in total knee arthroplasty (TKA) is multifactorial and dependent on alignment, ligament balance, patient, and implant factors. Abnormal loading has been linked to clinical failure; however, the respective contribution of each factor to failure is not well known. This study defined the effect of metal backing on loading patterns in the proximal tibia.

Bearing mobility affects tibial strain in mobile-bearing unicompartmental knee arthroplasty.

Mobile-bearing unicompartmental knees facilitate decreased polyethylene wear and restoration of knee kinematics. The purpose of this study was to quantify tibial strains during bearing mobility in UKA. Composite tibiae were implanted with cemented metal-backed tibial components and coated with photoelastic material, allowing "full-field" strain analysis.

Does ischial screw fixation improve mechanical stability in revision total hip arthroplasty?

Ischial screw fixation, albeit technically challenging, is postulated to provide additional mechanical stability in revision total hip arthroplasty (THA). Hemipelvis specimens were prepared to simulate revision THA, and an acetabular component with supplemental screw fixation was implanted. Three configurations were tested: 2 dome screws alone, 2 dome screws plus an additional screw within the dome, and 2 dome screws plus an ischial screw.

Effects of coronal plane conformity on tibial loading in TKA: a comparison of AGC© flat versus conforming articulations.

Conforming articulations potentially decrease polyethylene contact stresses in total knee arthroplasty (TKA); however, less is known about the effect of coronal geometry on tibial loading and clinical failure. This study examined the relationship between coronal plane geometry and loading patterns in the proximal tibia. Composite tibiae were implanted with modular, metal-backed tibial trays and were compressively loaded with conforming and nonconforming ultra-high molecular weight polyethylene (UHMWPE) tibial bearings and comparable femoral components.

Mechanical stability of novel highly porous metal acetabular components in revision total hip arthroplasty.

Highly porous metal acetabular components have emerged for revision hip arthroplasty. However, superior mechanical stability over traditional cementless components has not been demonstrated. Three different cementless acetabular components, including 2 highly porous tantalum designs, were inserted into hemipelvis specimens with a superolateral defect.

The effects of bone resection depth and malalignment on strain in the proximal tibia after total knee arthroplasty.

The clinical significance of tibial resection depth in total knee arthroplasty (TKA) is not clearly understood. The purpose of this study was to quantify the effect of tibial resection depth in TKA on tibial loading. Tibiae were coated with a photoelastic resin enabling full-field dynamic shear strain quantification in the tibial metaphysis during TKA loading.

Effects of femoral component size on proximal tibial strain with anatomic graduated components total knee arthroplasty.

Survivorship in total knee arthroplasty (TKA) is multifactorial and dependent upon alignment, ligament balance, patient characteristics, and implant factors. The contribution of each factor leading to implant loosening is not well known. This study defined the effect of femoral component sizing relative to tibial size on loading patterns in the proximal tibia.

The study of a light-activated albumin protein solder to bond layers of porcine small intestinal submucosa.

This study investigated the feasibility of bonding layers of porcine small intestinal submucosa (SIS, Cook Biotech, Inc.) with a light-activated protein solder. SIS is an acellular, collagen-based extracellular matrix material that is approximately 100 microns thick.

Bond strength of fibrin glue between layers of porcine small intestine submucosa (SIS).

This study investigated the strength of the bond between layers of small intestine submucosa (SIS, Cook Biotech, Inc., West Lafayette, IN) glued with commercially available fibrin glue (Haemacure Corporation). To determine the conditions leading to the highest bond strength, three parameters were varied: the concentration of the fibrin component, the concentration of the thrombin component, and the type of applicator used to apply the two components.