MUSCULOSKELETAL SYSTEM

Examination of the musculoskeletal system includes inspection and palpation of bones and soft tissues, measurement of active and passive joint range of motion, and assessment of stance and gait (35-38). It is complementary to neuromuscular assessment. As in previous parts of this chapter, only developmental variations are discussed.

Bone configuration and joint mobility change during the growing years (39,40). Full-term infants may lack as much as 25 degrees of elbow extension because of predominant flexor tone. In contrast, joint hyperextensibility and hypotonia allow increased passive motion in preterm infants. The scarf sign is a good illustration of excessive joint mobility in premature babies. Holding the infant's hand, the examiner draws one arm across the chest, like a scarf, toward the contralateral shoulder. In premature infants, the elbow crosses the midline, indicating hypotonic laxity of the shoulder and elbow joints. Full-term neonates have incomplete hip extension with an average limitation of 30 degrees as a result of early flexor tone predominance (39,40). The limitation decreases to less than 10 degrees by 3 to 6 months. At birth and during early infancy, hip external rotation exceeds internal rotation (39,41). With the resolution of early hip flexion attitude, internal rotation gradually increases. Differences between bilateral hip abduction, apparent shortening of one leg, and asymmetric gluteal and upper thigh skin folds are highly suggestive of congenital or acquired hip dysplasia or dislocation (40). Alignment of the femoral neck in neonates is consistent with prenatal coxa valga and increased anteversion. Femoral inclination is 160 degrees, and the angle of anteversion is 60 degrees. Respective adult measurements of 125 and 10 to 20 degrees develop postnatally and are accelerated by weight-bearing.

Persistent fetal configuration in nonambulatory children with physical disabilities enhances the effect of neurogenic muscle imbalance on the hip joint and contributes to acquired hip dislocation in spina bifida and cerebral palsy. The popliteal angle is 180 degrees in the hypotonic preterm infant, compared with 90 degrees in full-term neonates. A combination of increased flexor tone and retroversion of the proximal tibia causes this limitation of knee extension in mature newborns. By 10 years, tibial retroversion resolves spontaneously. An early varus configuration of the tibia contributes to the physiologic bowleg appearance in infancy and corrects itself by 2 to 3 years of age. A systematic review of skeletal development, with examination of the spine and extremities, is presented in Chapter 10.

Normal variations of stance and gait should not be mistaken for pathology in the growing child (37,42,43). Gait abnormalities evident on clinical observation include asymmetric stride length and stance phase in hemiparesis; toe walking and scissoring with lower extremity spasticity; crouch posture and gait in diplegic cerebral palsy; Trendelenburg's gait in motor unit diseases and hip dislocation; gastrocnemius limp with lack of pushoff in L4 to L5 weakness due to spina bifida; and various types of gait deviations associated with involuntary movements, such as ataxia, tremor, or dyskinesias, in dysfunction of the CNS.

SENSORY EXAMINATION

A complete examination of all peripheral sensory modalities is possible only in older children (44). Nevertheless, some modalities can be tested in infants and young children, and provide significant information. An infant who cries and squirms to move away from pinprick obviously perceives pain (45). A sleepy infant may be slow to respond and requires repeated stimuli. Withdrawal of the leg from painful stimuli may represent the triple flexion spinal withdrawal reflex in thoracic spinal cord lesion and should not be mistaken for active movement and presence of sensation. Comparing the infanf s reaction to pinprick on the arms or face differentiates actual sensory perception in such cases. Older infants respond to touch and vibration by turning toward or moving away from the stimulus. The presence of superficial reflexes signals an intact afferent and efferent reflex arc. The neuroseg-mental levels are T8 to T12 for abdominal reflexes, LI to L2 for the cremasteric reflex, and S4 to S5 for the anocutaneous reflex. In spina bifida, absence of these reflexes generally coincides with sensory deficit in the respective dermatomes. In young children who cannot be tested for proprioceptive function, ataxia and incoordination may suggest absence of this sensation. Testing of position sense is usually reliable by school age.

Cortical sensory function is impaired in parietal lobe damage (44,46). The most frequent childhood example is hemiparetic cerebral palsy. Disproportionately poor spontaneous function, neglect, and visual monitoring during use of the arm and hand are suspicious signs. Objective evaluation is generally feasible after 5 to 6 years of age, using the same technique as in adults for stereognosis, two-point discrimination (47), and topognosia with single or double sensory stimulation. Testing for graphesthesia may be attempted by using a circle or square. Around 8 years of age, the traditional number identification gives more accurate information. Cutaneous sensation and proprioception must be intact, and adequate cognitive ability is a prerequisite for testing cortical sensory function.

The child's age and ability to cooperate need to be considered in the examination of special senses. Moving a bright light or attractive object across the visual field is used to test vision in infants. At 1 month, the infant will follow to midline and at 3 months, from side to side through a 180-degree arc. The Stycar test and the illiterate E chart are used for screening preschool children at risk for visual deficit (48,49). At an early age, unilateral impairment or loss of vision and visual field defects, such as hemianopsia, are more likely to remain undetected than bilateral deficits. A child with strabismus or suspicion of diminished vision should see an ophthalmologist as soon as the problems are discovered. Early treatment with eye patching or corrective lenses is necessary to prevent amblyopia ex anopsia, or suppression amblyopia, partial loss of vision caused by cortical suppression to prevent diplopia (50,51). Central dysfunction of visual attentiveness, discrimination, and information processing may be misinterpreted as diminished vision and require both ophthalmologic and neuropsychological investigation. Cortical visual impairment usually shows improvement over time.

Screening of auditory function is a routine procedure in the neonatal nursery, pediatric office, and school. The examination of handicapped infants and children also should include a simple screening of hearing, eliciting the blink or startle reflex. Responses to handclapping; to speech of conversational loudness or whisper; perception of finger rubbing near the ear; and reaction to tuning fork, bell, or cricket toy are methods of testing. Absent, lost, or delayed speech, articulation deficits, inattentiveness to sound, a history of recurrent otitis media, head injury, or failure to pass the screening test indicates a need for complete evaluation of auditory function (45,50,52,53).

FUNCTIONAL EVALUATION

The pediatric rehabilitation examination is meaningless if the physiatrist does not construct from it a coherent picture of the child's functional achievements. This evaluation both complements and integrates the variety of information derived from all phases of the examination.

The developmental diagnostic evaluation is a convenient, functionally oriented assessment tool for infants and preschool children (21,54). Language, fine motor and adaptive skills, gross motor abilities, and personal-social behavior are the four major areas of function in the organizational framework of developmental testing. The same functional domains are considered in the evaluation of older children and adolescents. However, in these age groups, the examination includes a wider range of developmental expectations and abilities to function in school and society. ADLs and gross mobility skills need to be assessed in this context. In addition to speech, testing of language function includes other modes of communication: reading, writing, spelling, and, if indicated, augmentative communication. Drawing, design construction, arithmetic problems, and questions about handling hypothetical situations in daily life offer a brief, preliminary insight into cognitive and learning abilities. A number of specific assessment instruments were designed for various childhood disabilities (55-58). These instruments are useful functional assessment tools for their designated conditions and appropriately complement the customary developmental evaluation.

INFORMING INTERVIEW

Informing the family about the findings of the examination and their implications is an important responsibility of the physician. Factual information must be imparted with a caring attitude. Informing the parents about a newly established diagnosis should be considered as crisis intervention. A diagnostic label is insufficient without explanation of its meaning. The parents need to know the estimated prognosis, including the uncertainties of early prognostication, particularly in CNS dysfunction, with the possibility of multiple handicaps. Future needs in care and functional rehabilitation should be outlined. One should emphasize the need to avoid focusing on the physical disability alone and to consider the child's developmental and social needs. Effective counseling

and communication skills are essential for establishing a partnership between the physician and family to ensure the successful outcome of a comprehensive rehabilitation program. Information for ongoing support is crucial.

 
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