Categories Of Motor Impairment Research Paper Sample

Individuals with physical disabilities display a very wide and incredibly varied range of impairments that affect their function in a myriad of ways. While many specific motor impairments are associated with certain disabilities, most with physical disabilities are unique in the extent, severity, and nature of their motor impairments. One child or adult with cerebral palsy may present with completely different motor impairments than another child with the same diagnosis.
When working with individuals with disabilities, in order to understand the person’s physical functioning it is important to understand the characteristics of motor impairments. It can be difficult for those uneducated in motor impairment to understand why individuals with disabilities are unable to do certain things physically. A solid understanding of the nature of a person’s motor impairments is critical to guiding our interventions with them.

Motor impairments are obstacles that stand in the way of a child’s normal, timely acquisition of motor skills. For the purpose of this paper, motor impairments will be divided into four general categories: abnormal muscle tone; insufficient muscle strength, abnormal reflexes and movement patterns, and motor control and coordination (Martin, 2006, pp. 17 - 23).

Abnormal Muscle Tone

According to Martin (2006), “muscle tone refers to the amount of tension or resistance to movement within a muscle” (pp. 17). Our muscles, even when not actively in use, remain at varying states of rest (resistance). Muscles can have greater or lesser resistance to being stretched, greatly similar to the way that rubber bands have different stretching abilities (Martin, 2006, pp. 17). Typical muscle tone enables human beings to activate a muscle as exactly needed, when needed to complete a given task and relax it sufficiently when not in use (Anderson & Bhimani, 20140, p. 1-2).
Many people with physical disabilities display differences in tone. Hypertonia, or spasticity, refers to high muscle tone; those with high muscle tone have stiff muscles that feel tighter to the touch, resist being stretched, either during intentional use, such as reaching out to grasp something, or passively, such as when pulling an infant’s arms up to dress or undress them (Anderson & Bhimani, 20140, p. 2). Conversely, hypotonia, or flaccidity, refers to low muscle tone, which looks very similar to muscle weakness - muscles are easily stretched, difficult to activate, and feel very soft to the touch (Martin, 2006, pp.17). Some individuals also present with fluctuating tone, which refers to when muscle tone varies between low and high in the same muscle (Martin, 2006, pp.18). An individual with abnormal muscle tone may experience fluctuations in tone influenced by an their posture or body position, state of alertness, mood, level of distress, and intent to move purposefully (Anderson & Bhimani, 2014, p. 5-9).

Abnormal Reflexes and Movement Patterns

Individuals with physical disabilities often present with abnormal movement patterns that negatively impact their ability to use their limbs in a purposeful manner. These patterns are generally associated with differences in tone, often in those with spasticity, and present in a predictable way. Child with high tone in the lower body may display “scissoring” of the legs, with both legs turning inward and crossing over each other. These movement patterns are not functional; they interfere with normal movement and make it difficult for individuals to use their limbs purposely and intentionally, like the child learning to walk who struggles to maintain normal the limb position necessary for walking against a slight scissoring pattern.
Interestingly, many abnormal movement patterns are also associated with early reflexes that were never fully integrated. According to the Medline Plus Medical Encyclopedia, a reflex is “a muscle reaction that happens automatically in response to stimulus” (2013). Humans are born with reflexes that serve to ensure our survival before we develop enough cognitively and physically to act intentionally (“Infant Reflexes,” 2013). Many of these reflexes are easily recognizable when observing infant behavior, such as the suck reflex, which causes an infant to latch onto anything placed in its mouth (“Infant Reflexes,” 2013). In addition to these, infants also are born with a number of other lesser-known reflexes serve their purpose in infancy, but can interfere with normal movement as a child ages if they are not properly integrated (Martin, 2006, pp. 19-21). Children who do not integrate their primitive reflexes will develop abnormal reflexes, such as the child who does not integrate the tonic neck reflex and instead develops an symmetrical tonic neck reflex, which causes the arms to bend or straighten in relation to the child’s head position, making it difficult for an infant learning to crawl, as their ability to maintain an upright position on hands and knees is dependent upon them maintaining their head and neck in extension (Martin, 2006, pp. 21). Abnormal reflex patterns, while rooted in primitive reflexes present in infancy, persist throughout an individual’s lifetime and require a great deal of intervention to overcome (Martin, 2006, pp. 21).

Muscle Weakness

Many individuals with physical disabilities present with weakness of the muscles in their bodies for a variety of reasons. Some muscle weakness is secondary to lack of use, such as in an adult paralyzed from the neck down who is wheelchair bound and exhibits poor strength in the lower extremities (“Dexterity and Mobility Impairment Fact Sheet”, 2007). Abnormal tone and abnormal reflexes or movement patterns can seriously impact an individual’s ability to develop and maintain adequate strength, such as the adult who is unable to use their arm purposefully due to high spasticity after a stroke and lose strength in that arm over time (“Dexterity and Mobility Impairment Fact Sheet,” 2007). An infant with hypotonicity who has difficulty maintaining an upright position, such as during tummy time, and tires easily will fatigue quickly during activity and develop the strength needed to crawl much more slowly than a typical infant.
Weakness is one of the characteristics of motor impairments that is easiest to address when occurring in isolation secondary to an injury or simply to disuse; unfortunately, for most individuals with physical disabilities, the presence of other motor impairments does present an added challenge when attempting to increase muscle strength (Martin, 2006, pp. 22).

Lack of Motor Control and Coordination

Muscle control refers to our ability use our muscles for purposeful, goal-directed action by adjusting the force, timing, and speed of our muscle movements (Martin, 2006, pp. 21). Problems with muscle control, as well as problems with the integrity of the bones, joints, and muscles, cause an individual to exhibit poor coordination; when an individual has good muscle control, he or she can be said to have good coordination (“Movement- uncoordinated,” 2013). High and low tone, muscle weakness, and abnormal reflexes are all contributing factors to an individual’s struggle with motor control and coordination, making individuals with physical disabilities more likely to exhibit poor motor control and thus poor coordination (“Movement- uncoordinated,” 2013). Individuals with poor coordination or control often have difficulty with mobility and balance, which presents many safety risks. A child with Downs Syndrome who exhibits poor control of the muscles in his arms and hands (fine motor control) can learn to tie his own shoes with a great deal of time, patience, and practice. Fortunately, like muscle strength, muscle control is a skill that can be improved with time and practice.

Conclusion

An individual’s level of physical disability is greatly impacted by how significantly affected they are in each of the categories of motor impairment. It is critical that any interventions are structured so as to be supportive of an individual’s unique physical abilities and needs. Understanding the full and complex nature of every individual’s physical disability requires practitioners and educators to not just be competent in defining the categories of motor impairments exhibited by these individuals, but in understanding the unique relationship and correlation between different motor impairments.

References

Anderson, L., & Bhimani, R. (2014). “Clinical Understanding of Spasticity: Implications for
Practice.” Rehabilitation Research and Practice, vol. 2014 . doi:10.1155/2014/279175
Dexterity and Mobility Impairment Fact Sheet. (2007). Georgia Tech Research Institute.
Retrieved from
http://accessibility.gtri.gatech.edu/assistant/acc_info/factsheet_dexterity_mobility.php
Infant Reflexes. (Updated 2013, February 12). In Medline Plus Medical Encyclopedia. Retrieved from http://www.nlm.nih.gov/medlineplus/ency/article/003292.htm
Martin, S. (2006). Teaching Motor Skills to Children with Cerebral Palsy and Similar Movement
Disorders. Bethesda, ME: Woodbine House.
Movement- uncoordinated. (Updated 2013, February 23). In University of Maryland Medical
Center Medical Encyclopedia. Retrieved from http://umm.edu/health/medical/ ency/
articles/movement-uncoordinated