The ventricular action potential has a long refractory period so that the mechanical response of the ventricle will be discrete; one coordinated mechanical response per electrâ¦ical activation sequence. Otherwise, with additional electrical stimuli, the mechanical responses would summate producing a prolonged contraction.
Microfracture Technique. Overview. Microfracture is a surgical technique that has been developed to treat chondral defects, which are damaged areas of articular cartilage of the knee. It is a common procedure used to treat patients with full thickness damage to the articular cartilage that goes all the way down to the bone.
The first efforts to address cartilage injury focused on getting the body to produce new articular cartilage as a response to injury to the subchondral bone; a form of the technique, microfracture, is still widely used and is, in fact, the current standard of care for the treatment of cartilage injury in the United States.