Muscular System Case Study

 

A 32-year-old woman sees her family physician because of episodes of severe pain in her hands, associated with skin color changes and coldness of the hands.These attacks usually occur during the winter after exposure of the hands to cold.The physician precipitated one of these attacks by having the patient put her hands in a basin of cold water.At first the hands turned white, and this was associated with increasing pain in the fingers.Then the hands turned slightly cyanotic (bluish), followed rapidly by redness and throbbing discomfort.Gradually the pain disappeared, and the hands returned to normal color.The doctor diagnosed the patient with Raynaudís disease.

 

  In order to respond thoroughly to these questions you will need to investigate the role of blood vessels in control of blood flow to muscle tissue.

1.)Describe structure of skeletal muscle at sarcomere level. Explain the Sliding-Filament Mechanism for muscle contraction.  

2.) What is responsible for the color(s) of the affected fingers?

3.)   What would be the normal response of blood vessels in the hand to warming or cooling?

4.)    Is there anything about the smooth muscles of the fingers and hands that would make them more temperature-sensitive than skeletal muscles?

5.)    What is responsible for the bright red color of the fingers after an attack?

6.)    Is reduced ATP synthesis and a form of rigor mortis a reasonable explanation for this cooling-induced vasospasm?

7.)    In what sense is the term vasospasm misleading?