cerebral palsy affects motor development. A brief introduction to cerebral palsy will be given, and then a more detailed look at exactly how motor development is affected will be entered into.
Cerebral palsy is a general term for a variety of disorders caused by damage to the brain (Schuelein, 2002). The damage occurs before or during birth or in the first few years of life, and may cause severe crippling, or the symptoms may be so mild that they hardly interfere with the patient's activities (Schuelein, 2002).
There are several types of cerebral palsy, and all involve lack of muscle control: common effects of the disorder include a clumsy walk, lack of balance, shaking, jerky movements, and unclear speech (Schuelein, 2002). In many patients, the brain damage also causes mental retardation, learning disability, seizures, and problems in sight and hearing (Schuelein, 2002).
In most cases of cerebral palsy, the causes of faulty growth of the brain that result in cerebral palsy cannot be determined (Schuelein, 2002). In some cases, however, brain damage may result from illness in the mother during pregnancy; rubella can severely harm an unborn child, even though the mother may have had only mild symptoms or none at all during pregnancy (Schuelein, 2002).
Brain damage can also occur during the birth process, especially in premature births (Schuelein, 2002). In babies born after a normal term of pregnancy, brain damage may occur if there is a significant period of hypoxia (lack of oxygen), which can cause brain cells to die (Schuelein, 2002). After birth, a baby may develop cerebral palsy if disease or injury damages the brain; during the first year of life, infections and accidental head injuries are the most frequent causes of the condition (Schuelein, 2002).
There are four chief types of cerebral palsy: these are (1) ataxic, (2) athetoid, (3) hypotonic, and (4) spastic (Schuelein, 2002). In the ataxic form, the patient's voluntary movements are jerky, and a loss of balance is suffered (Schuelein, 2002). In the athetoid type, the person's muscles move continually; these movements prevent or interfere greatly with voluntary actions (Schuelein, 2002). A person with hypotonic cerebral palsy appears limp, and the person can only move a little or not at all because the muscles cannot contract (Schuelein, 2002). Spastic cerebral palsy patients have stiff muscles and cannot move some body parts (Schuelein, 2002). A person with cerebral palsy may have more than one muscle disorder, and the person may be only slightly disabled or completely paralyzed (Schuelein, 2002).
Now we have seen what cerebral palsy is, how it can be classified (in borad terms) and how cerebral palsy can be caused, and, further, have looked at the various types of cerebral palsy, we will look in more detail at the specific effects of cerebral palsy on motor development, through a review of the measures used by clinicians to assess cerebral palsy.
Cerebral palsy can be caused by a static lesion to the cerebral motor cortex that is acquired before, at, or within 5 years of birth (Dabney et al., 1997). Multiple causes for the condition exist and include cerebral anoxia, cerebral hemorrhage, infection, and genetic syndromes (Dabney et al., 1997). Cerebral palsy is commonly classified according to the type of movement problem that is present (spastic or athetoid) or according to the body parts involved (hemiplegia, diplegia, or quadriplegia) (Dabney et al., 1997).
To care for children with cerebral palsy, a team approach is most effective; the team should include pediatrician and orthopedist, among others (Dabney et al., 1997). In the non-ambulatory patient, good sitting posture, the prevention of hip dislocation (spastic hip disease), and the maintenance of proper custodial care are prime concerns (Dabney et al., 1997). Careful monitoring and treatment of spastic hip disease and the correction of scoliotic spinal deformity are also important (Dabney et al., 1997). In the ambulatory patient, the main goal is to maximize function; computerized gait analysis in patients with complex gait patterns helps to show whether orthotic or surgical treatment is indicated (Dabney et al., 1997).
Damanio and Abel (1996) showed that certain gait parameters, that are used to measure the degree of the lack of muscular control, are related to the computerised gait analysis, confirming that gait is representative of general motor status in cerebral palsy patients, and that the Gross Motor Function Measure and gait analysis are therefore complementary measures for the functional assessment of cerebral palsy patients (Damanio and Abel, 1996). The use of gait to assess motor function can therefore be a useful tool with which to assess the severity of cerebral palsy within the patient, and also to design the most effective treatment.
Further to Damanio and Abel's (1996) paper, and Dabney et al.'s (1997) report, Barbosa et al. (2003) argued that understanding the natural history of development in children with cerebral palsy is important for studying the consequences of early intervention, and as part of this hypothesis looked at the Test of Infant Motor Performance and the Alberta Infant Motor Scale for a variety of infant ages, and found that the Alberta Infant Motor Scale is most effective in clinical settings, due to the greater ease of use of this scale for clinicians (Barbosa et al., 2003).
In terms of the effects on motor development of cerebral palsy, as opposed to the diagnostic uses of deviances from 'normal' motor function, Hanna et al. (2003) have studied the development of hand function amongst children with cerebral palsy. As part of the study, assessments of hand function and the quality of upper-extremity movement were conducted on 29 males and 22 females and on four other occasions over 10 months (Hanna et al., 2003). Linear mixed effects modeling was used to estimate average developmental curves and the degree of individual differences in the patterns of development which were conditional on the body-site distribution of CP and severity of impairments (Hanna et al., 2003).
The results indicate that hand function in this population of children with cerebral palsy develops differently from overall upper-extremity skills with declines in function in upper-extremity skills being more common and pronounced among older children (Hanna et al., 2003). Substantial inter-individual variation was, however, found, and it was found that the distribution of cerebral palsy and the severity of impairments in motor function were significant predictors of development (Hanna et al., 2003).
In 2002, Rosenbaum et al. published a landmark paper on the subject of motor function in cerebral palsy and its application for prognoses (Rosenbaum et al., 2002). The paper stemmed from a lack of a valid classification method for the degree of severity of cerebral palsy, and its objective was to describe the gross pattern of motor development in children with cerebral palsy by severity, suing longitudinal observations (Rosenbaum et al., 2002). The study developed five distinct motor development curves, with which important differences in the rates and severity of cerebral palsy can be predicted, giving a method for evidence-based prognostication of gross motor progress in children with cerebral palsy (Rosenbaum et al., 2002).
Yokochi has been an important contributor to the literature concerning motor function in cerebral palsy patients. His 1993 paper looked at motor function in infants with athetoid cerebral palsy, through the analysis of the motor function of 35 children with athetoid cerebral palsy using videotape recordings made at five to eight months of age (Yokochi et al., 1993). Many infants showed asymmetric tonic neck, Moro and Galant reflexes, and the movements which proved to be difficult included: keeping a symmetric supine posture, isolated movements of the hips and knees, forward extension of the upper extremity, extension of neck and trunk in the prone position and in ventral suspension, flexion of the neck in the traction response, and weight support by the upper extremities (Yokochi et al., 1993). Asymmetric or excessive opening of the mouth was also present in all infants, indicating a defect in motor function in all patients tested; it was hypothesised that the grade of difficulty for each posture and movement might reflect subsequent motor disability at three years of age (Yokochi et al., 1993).
An earlier paper, Yokochi et al. (1990) looked at the gross motor patterns in children with cerebral palsy, by analysing rolling, sitting, and crawling patterns in 72 children with cerebral palsy and spastic diplegia; the relation between these patterns and the severity of the locomotive disability was studied (Yokochi et al., 1990). In rolling, trunk rotation and elbow support were difficult for the most severely diplegic children (Yokochi et al., 1990). When sitting, most patients had a between-heel sitting pattern in which the thighs were adducted and the knees were flexed (Yokochi et al., 1990). When crawling, the reciprocal thigh movements were insufficient and accompanied by lateral bending of the trunk in many patients (Yokochi et al., 1990). In the more impaired patients, the thighs supported the weight in flexion and did not move reciprocally (Yokochi et al., 1990). Creeping on the elbows without reciprocal leg movements was demonstrated in the most…