Design of Anatomical Population-Based and Patient-Specific Radial Head Implants.

Purpose: The objective of this study was to characterize the morphology of the radial head and design population-based anatomical and patient-specific radial head implants.

Methods: Computed tomography (CT) images of 50 normal cadaveric upper extremities (34 male, 16 female) were obtained using a 64-slice CT scanner. Surface models were ellipse-fitted and characterized.

Effect of Radial Head Implant Shape on Radiocapitellar Joint Congruency.

Purpose: Radial head arthroplasty is indicated in displaced fractures in which comminution precludes successful internal fixation. Many types of radial head implants have been developed varying in material, methods of fixation, and degrees of modularity and geometry. The purpose of this study was to investigate the effect of radial head implant shape on radiocapitellar joint congruency.

Accuracy assessment of 3D bone reconstructions using CT: an intro comparison.

Computed tomography provides high contrast imaging of the joint anatomy and is used routinely to reconstruct 3D models of the osseous and cartilage geometry (CT arthrography) for use in the design of orthopedic implants, for computer assisted surgeries and computational dynamic and structural analysis. The objective of this study was to assess the accuracy of bone and cartilage surface model reconstructions by comparing reconstructed geometries with bone digitizations obtained using an optical tracking system. Bone surface digitizations obtained in this study determined the ground truth measure for the underlying geometry.

Effect of radial head implant shape on joint contact area and location during static loading.

Purpose: To examine the effect of implant shape on radiocapitellar joint contact area and location in vitro.

Methods: We used 8 fresh-frozen cadaveric upper extremities. An elbow loading simulator examined joint contact in pronation, neutral rotation, and supination with the elbow at 90° flexion.

The effect of radial head implant shape on radiocapitellar kinematics during in vitro forearm rotation.

Background: A number of radial head implants are in clinical use for the management of radial head fractures and their sequelae. However, the optimal shape of a radial head implant to ensure proper tracking relative to the capitellum has not been established. This in vitro biomechanical study compared radiocapitellar joint kinematics for 3 radial head implant designs as well as the native head.

Validation of a finite element model of the human elbow for determining cartilage contact mechanics.

It is important to study joint contact mechanics to better understand the processes which lead to cartilage degradation. The purpose of this study was to develop and validate a finite element (FE) model of a human elbow capable of predicting joint contact area and stress. A cylindrical constrained elbow joint loading apparatus was used to measure the cartilage compression and contact area for a single cadaveric specimen.

Capitellar excision and hemiarthroplasty affects elbow kinematics and stability.

Introduction: Capitellar hemiarthroplasty is proposed as a reconstructive option for isolated capitellar deficiency, but there is limited data on its effect on elbow biomechanics. This study assessed the effect of capitellar excision with and without replacement on elbow kinematics and stability, and evaluated 2 different implant surface shapes.

Materials And Methods: Ten cadaveric arms were tested with an upper extremity joint simulator.