Related Experiment Video
Updated: Jun 4, 2026

In Vitro Application of a Wireless Sensor in Flexion-Extension Gap Balance of Unicompartmental Knee Arthroplasty
Published on: May 5, 2023
The role of constraint in contemporary modular knee designs
P D Postak1, C S Heim, A S Greenwald
1Orthopaedic Research Laboratories, The Mt. Sinai Medical Center, Cleveland, OH.
Abstract:
The current success of total knee arthroplasty (TKA) as a solution for arthritic problems about the knee is reflected in the increasing number of these procedures. The 1992 annual hospital discharge summaries indicate approximately 160,000 TKAs were performed in the United States for both primary and revision indications. Clinical success of TKA is rooted in a refined appreciation of patient habitus, technical proficiency and implant design. The understanding of this integrated triad has evolved over the past two decades. The evolution of knee implant design reflects recognition of the principle that implant geometry, acting in concert with surrounding soft tissues, determines the joint stability, range of motion and implant/bone interface forces. Interchangeable plateau geometries associated with modular designs, represent a recent development which permit an optimization of these interactions for a specific patient pathology. This paper describes a comparative evaluation of the geometrical constraint offered by six primary modular knee systems and describes their clinical applicability.
Related Concept Videos
Knee Joint
A total of seven ligaments support the knee joint. The patellar ligament, which is also attached to the quadriceps femoris group...
Constraints and Statical Determinacy
Development of the Limb Synovial Joints
The mesenchymal stem cells differentiate into chondrocytes that form the hyaline cartilage, and later the cartilaginous model of the bone. This model further transforms into a bone. This process is known as endochondral ossification.
During development, the limbs...
Ankle Joint
Functional Classification of Joints
The functional classification of joints is determined by the amount of mobility between the adjacent bones. Joints are functionally classified as a synarthrosis or immobile joint, an amphiarthrosis or slightly moveable joint, or as a diarthrosis, a freely moveable joint. Fibrous and cartilaginous joints can be functionally classified as either synarthroses or amphiarthroses, whereas all synovial joints are classified as diarthroses.
Synarthrosis
An immobile...
Bones of the Lower Limb: Femur and Patella