Recurrent patellar instability is a common pathology and typically affects younger and more active patients. To prevent complete lateral dislocation of the patella, several osseous and soft-tissue procedures have been previously described, including reconstruction of the medial patellofemoral ligament (MPFL), which has been identified as the primary medial stabilizer of the patella. Several tec...

Complementary to axial, lateral displacement and strain can provide important information on the biological soft tissues. In this paper, the effects of key parameters (i.e., lateral displacement, pitch, beamwidth, beam overlap and interpolation) on lateral displacement estimation were investigated, in simulations and homogeneous phantom experiments, using lateral rigid motion only to study its ...

BACKGROUND The use of different coordinate system definitions for the patella leads to difficulties in comparing kinematic results between studies. The purpose of this work was to establish the effect of using a range of coordinate system definitions to quantify patellar kinematics. Additionally, intra- and inter-investigator repeatabilities of the digitization of anatomic landmarks on the pate...

BACKGROUND Tight regulation of cell motility is essential for many physiological processes, such as formation of a functional nervous system and wound healing. Drosophila Abl negatively regulates the actin cytoskeleton effector protein Ena during neuronal development in flies, and it has been postulated that this may occur through an unknown intermediary. Lamellipodin (Lpd) regulates cell motil...

INTRODUCTION A number of structures, both passive and active, contribute to the force balance on the patella. To understand the relative contribution of each quadriceps component to the balance of forces on the patella, the individual moment arms of the quadriceps tendons must be known. Previous studies have investigated the moment arm of the patellar tendon and the quadriceps muscle as a whole...

The management of osteoarthritis of the knee associated with patellar instability secondary to external tibial torsion > 45 degrees is challenging. Patellofemoral biomechanics in these patients cannot be achieved by intra-articular correction using standard techniques of total knee replacement. We reviewed seven patients (eight knees) with recurrent patellar dislocation and one with bilateral i...

One of the main problems after total knee arthroplasty is pain in the patellofemoral joint, which in some cases leads to revision surgery. Rotation of the femoral component has a significant influence on the path followed by the patella within the patellofemoral joint. We examined the influence of rotation of the femoral component after total knee arthroplasty on patellar tilt. We retrospective...

BACKGROUND Medial patellofemoral ligament (MPFL) reconstruction is performed to prevent recurrent instability, but errors in femoral fixation can elevate graft tension. HYPOTHESIS Errors related to femoral fixation will overconstrain the patella and increase medial patellofemoral pressures. STUDY DESIGN Controlled laboratory study. METHODS Five knees with patellar instability were represe...

Complications involving the knee extensor mechanism and patellofemoral joint occur in 1% to 12% of patients following total knee arthroplasty and have major negative effects on patient outcomes and satisfaction. The surgeon must be aware of intraoperative, postoperative, and patient-related factors that can increase the rate of these problems. This review focuses on six of the most commonly enc...