Common Effects of Immobilization - Essay Example

1. Define immobilization.

Immobilization is the process of holding a joint in its position using materials such as cast, splint, and brace. It is generally done to limit the movement of an injured area as it heals.

2. 
   How does immobilization affect soft tissues like ligaments and joint capsules?

Immobilization causes soft tissues such as ligaments and capsules to shrink. During immobilization, the collagen turnover increases with the enhanced process of synthesis and degradation. However, after immobilization, a substantial decrease in the quantity of large-diameter collagen fibrils arises. In highly ordered tissues such as ligaments, immobilization distorts the array of any new fibrils that are formed. The distortion in the array causes tissue failure and a reduction in the ultimate load. Similarly, in inherently extensible tissues such as capsules, the disordered fibrils impede flexibility by producing gliding impediments along with their structures. The gliding impediments are thought to occur due to the absence of matrix orientation controls forced by physical constraints (Hammer, 2007).

3. In a joint, immobilization can cause a decrease in the available motion (ROM) from the development of "adhesions"; what is an adhesion, and what are some possible ways for us to treat it?

Adhesion is an abnormal cross-linking between the connective tissue fibers of a joint. It is caused by prolonged immobilization. When a joint is immobilized, its connective tissue loses flexibility. As a result, the fibers connect abnormally (Lederman, 2005). In order to treat adhesion, the joint is moved either actively or passively. Active motion is the actual movement of the joint, which involves physical exercises such as walking or any related activity. In this case, the immobilized joint is subjected to normal joint exercises that involve weight-bearing activities. On the other hand, passive motion is a forced movement of the joint. It involves the application of external force and heat to the joint. Subjecting an immobilized joint to heat and load disrupts the adhesion between intermolecular cross-linking and gross-structures between fibers in the connective tissue (Hammer, 2007).

4. When a weight-bearing body segment is immobilized and/or restricted from its usual weight-bearing duties, the bone becomes weaker. Describe at least 3 reasons why the bones become weaker.

First, bones become weaker because they lack mechanical forces acting on them. In a normal situation, the mass of a bone is maintained by a continuous coupling between bone formation and resorption by osteoblasts and osteoclasts respectively. The two processes are enhanced by the presence of mechanical forces resulting from the muscles’ weight. However, when the weight-bearing segment is immobilized, it limits the effect of mechanical forces, which in turn weakens the bones. Thus, if the bones are subjected to mechanical forces, they can break easily (Dutton, 2011). Second, bones become weaker because they lose calcium during immobilization. The loss of calcium causes osteopenia, which predisposes the bones to pathogenic fractures. As a result, the bones become thin (Hockenberry, Wilson, & Wong, 2012). Third, bones become weak because of the effect of imbalanced opposing forces, which is caused by muscle shrinking. When a joint is immobilized, the muscles controlling it may shrink at different rates. Thus, a particular group of muscles may pull the bones with a resultant force in a particular direction. This makes the bone susceptible to fractures (Boyle & Roth, 2012).

5. 
   Describe how immobilization affects the muscles and tendons that cross over a joint that is immobilized and then identify types of exercise we could use to treat the restrictions.

When muscles are immobilized, they lose their strength and tension per unit cross-sectional area. A rapid increase in muscle fatigability also arises. Similarly, immobilization of tendons causes a change in their structure and material properties. For instance, the absence of stress causes a reduction in their cross-sectional area and mechanical properties. The parallel structure of fibrils and cells also becomes disorganized. The absence of stress also increases collagen turnover, which eventually causes a net decrease in its mass. Immobilization effects on both muscles and tendons can be treated with two categories of exercises. They include strength and endurance exercises. The strength exercise involves an increased magnitude of the load while endurance exercise involves increased load frequency or time (Magee, Zachazewski, & Quillen, 2007).