Pediatricians can help their cerebral-palsy patients by performing a relatively simple musculoskeletal examination to see if structural change has taken place. In this way the child with cerebral palsy can be referred to an orthopedic surgeon relatively early in life, before serious structural changes can occur. If at all possible, concentrated early orthopedic management should allow completion of the intensive treatment program for the child by the time he is eight years old.
The musculoskeletal examination is necessary because muscles in the child with cerebral palsy undergo shortening as a result of continuous spasticity. This shortening is sometimes referred to as "myostatic contracture." Histologic studies have not shown fibrosis in cerebral-palsy patients, so the shortening probably occurs within the sarcolemmal membranes and muscle fibers.
Contractures, particularly about the hip, occur very early in life and tend to become more severe as the child grows. This increase in contractures is thought to be due to the increasing bone length, with which the muscle fails to keep the pace. There is little documented evidence that contractures are prevented by continuous bracing, particularly those in the hip abductors and flexors.
Therapeutic methods have not demonstrated clearly a decrease in a contracture due to spastic paralysis. Physical therapy methods (e.g., range of motion of joints) would have to be almost continuous, when, in effect, they are usually applied at the most once per day, for 15 to 20 minutes. Severity of the contracture and its development are more likely related to the severity of the hypertonus, and the balancing effect of spastic antagonistic muscles.
As a result of the shortening of muscles and the growth of the child, a number of structural changes can occur. Among them are joint contractures, dislocations, cartilage degeneration, and bone changes in the upper and lower limbs and spine.
Joint contracture can occur after a joint has been held in an abnormal position for some time; the joint capsules themselves become shortened. The collagen in the capsule rapidly undergoes considerable change so that the normal elasticity of the capsule is lost. Hip-flexion contractures and knee-flexion contractures are common examples of superimposed capsular change.
Subluxation and dislocation are other structural changes that may occur. The joint that usually subluxates and dislocates is the hip, because of the continuous pull and contracture of the hip adductors and the iliopsoas, combined with persistent fetal femoral anteversion in which the head, neck, and trochanteric region of the femur are twisted forward beyond the range that is normal for the child's age.
A secondary acetabular dysplasia develops when the femoral head is not located in the acetabulum. Subluxation and dislocation of the hip in cerebral palsy is an acquired deformity and can be easily documented by serial x-ray examinations.
A reasonably accurate generalization is that hip dislocation occurs only in the nonambulatory sitting patient. The mean age of dislocation is seven years. Subluxation occurs in patients who are ambulatory but must use crutches or walkers - that is, those who are partially weight-bearing. The fully weight-bearing, walking patient does not subluxate or dislocate but has an in-toed gait pattern due to hip internal rotation in the swing and stance phases of gait see box).
Dislocated hips in children are usually not painful until the teen years or later. Hip pain is due to degeneration of the articular cartilage which inevitably occurs when cartilage contact is lost. The patient has then developed degenerative arthritis and it is too late to do anatomical reconstructive surgery, such as soft-tissue release, osteotomy, and relocation of the hip.
All other reconstructive procedures, such as proximal femoral resection, arthroplasty, total hip arthroplasty, and hip arthrodesis, are compromises and not ideal solutions. Ideally, of course, the tendency for the bones to dislocate should be discerned before the dislocation occurs and prevented by early adductor tenotomy, anterior-branch-obturator neurectomy, and iliopsoas tenotomy.
Cartilage degeneration occurs when cartilage is constantly under compression. Forcing wedging of the ankle into dorsiflexion when there is a contracture of the gastrocnemius soleus muscle ("heelcord contracture") will result not in lengthening of the muscle but rather in compression of the articular surface of the talus.
When this is done, the talus is in the position of a nut wedged between two "limbs" of the nutcracker - the bones of the foot and the bones of the leg. Forced wedging in plaster, consequently, is not conservative treatment but probably should be considered radical.
Similar cartilage degeneration with resultant stiffness of hips can occur in forced overabduction of the hips. In such cases the femoral head is compressed tightly against the acetabulum, with resultant change in the articular cartilage.
Bone changes may be manifest in leg-length inequality or as torsional changes. Leg-length inequality and hemiplegia is a common condition, but the difference in length rarely exceeds 1.5 cm. It should be looked for in children with one-sided paralysis. Torsional changes in the bones occur most commonly in the tibia and fibula in which there is excess of external tibial torsion as a compensatory change for an excessive hip internal rotation during gait.
Inversion deformities of the foot may be varus or pes valgus. Varus deformities usually are initially caused by spasticity of the posterior tibial muscles (or, occasionally, of the anterior tibial muscles). If the condition is allowed to persist into adolescence, fixed changes occur, and the only solution at that age is a triple arthrodesis. Early surgical lengthening or transfer of tendons can avoid the need for more drastic measures later on.
Pes valgus deformities are more common in cerebral-palsy children than varus problems. In the child with pes valgus the talus is plantar-flexed and the calcaneus is in equinus - thus, the child walks on his toes without touching his heel to the ground. The parents may try to hide the deformity by having the child wear high-top corrective shoes, in which case the condition will persist into adolescence, when the feet will become rockerbottomed and painful. At such a late age a triple arthrodesis usually will be necessary to correct the problem. Triple arthrodesis is a difficult operation in valgus feet, and the end results are not always as satisfactory as one could wish for. Consequently, early extra-articular procedures to stabilize the subtalar joint can be recommended.
Metatarsus adductus due to spasticity of the abductor hallucis is occasionally seen in patients. In the younger ages, it is still a dynamic deformity and can be easily treated with an abductor-hallucis tendon release. Later on, when it becomes fixed and the foot is markedly adducted, the only solution is an osteotomy of the bones.
Bone deformities in the upper limbs usually involve the carpal bones as a result of a persistent flexion contracture of the wrist. After a period of years the carpal bones deform in the direction of the contracture and correction by simple tendon lengthening or transfer will be impossible. In the adolescent years, such deformities, if they are to be treated at all, usually need excision of the proximal carpal row of bones and arthrodesis of the wrist.
Persistent flexion deformity of the elbow and pronation of the forearm lead to posterior subluxation of the head of the radius and posterior bowing of the ulna. This permanently limits elbow extension. Such changes may be prevented by very early pronator-teres tenotomy. Shoulder dislocation can occur in patients who have athetosis. I know of no preventive measures.
The major structural change in the fingers is the "swan neck" deformity. In this, the proximal interphalangeal joints hyperextend and the distal joint flexes. At times this can be disabling as the fingers lock recurrently in hyperextension.
Spine changes. Scoliosis is the most prominent structural change in the spine, and it occurs much more frequently in children with cerebral palsy than with the other structural changes. Scoliosis becomes particularly severe when cerebral palsy has affected all parts of the body, resulting in quadriplegia.
Structural scoliosis is due to a progressive curvature of the spine that is secondary to the spastic paralysis and probably secondary to the dysequilibrium. Severe pelvic obliquity can occur as a result of the scoliosis, so that the child becomes extremely uncomfortable - and balance becomes difficult - while sitting, because of unequal and abnormal pressure on one ischial tuberosity.
Degenerative arthritis of the cervical spine has been noted in patients with athetosis after they have lived many years with involuntary neck motion. This can be painful and may require surgical fusion.
THE ORTHOPEDIC EXAMINATION
The orthopedic examination will include observation of the child's gait, overall bone structure, and function of the upper and lower limbs.
Gait. If the child is able to walk, observation of the gait should be the beginning of the examination. Observations can be made on the position of the joints during stance and swing phases. Usually there are three gait patterns in the most common type of cerebral palsy - spastic diplegia: (1) flexed and internally rotated hips with flexed knees, (2) flexed and internally rotated hips with hyperextended knees, and (3) flexed and internally rotated hips with phasic or balanced knee function.
If the knee-flexion deformity is greater than 15 degrees during the stance phase of gait, the forces on the quadriceps to keep the patient erect, as well as the intra-articular forces in the knee joint, become geometrically greater. After 15 degrees of knee flexion, gait becomes more energy-consuming and fatiguing and less functional.
Structure. Posteriorly, the shoulder and pelvic level should be observed. An elevated shoulder, a pelvic obliquity, and a loin crease with increased fullness in the opposite loin is an indication for a radiograph to rule out scoliosis. Flexion of the trunk to 90 degrees will make a rib hump obvious as an earlier sign of thoracic spine curvature. When viewed from the side, kyphosis and lordosis with increased pelvic inclination can be discerned.
A ruler placed against the apex of the thoracic vertebra and against the sacrum should be perpendicular to the floor in normal kyphosis of the thoracic spine. As the ruler deviates posteriorly, kyphosis is suspected and a standing lateral radiograph of the thoracic and lumbar spine should be ordered. The ruler test also gives some clinical indication of the degree of lordosis. Usually the space between the straight edge and the midlumbar spine is up to 4 cms. A 7-cm. measurement indicates lordosis beyond the mean.
Lordosis can be secondary to the kyphosis or, more often, to the hip-flexion contracture, in which the pelvis inclines anteriorly as a compensatory mechanism for the flexion contracture.
Upper limbs. With the patient securely seated and the arms resting on a table or lap board in a wheelchair, hand function can be examined by simple observation of pinch, grasp, and release. Small beads test pinch, and grasp is tested with a cylindrical object, such as a piece of wood or dowling. Position of the wrist, fingers, and thumb can be easily observed.
Sensation in the hemiplegic hand is often deficient. Stereognosis* is tested with the patient blindfolded. He is handed test objects, first in one hand, then the other, and asked to tell whether they are round or square, etc. The test materials are made of thin plywood - a circle, a square, diamond, or triangle. Smooth and fuzzy surfaces can be tested with a Ping-Pong ball and a ball coated with floe spray paint.
The fact that the child does not have normal stereognostic function has to be pointed out to both patient and parent. No remedial methods have ever been reported to cure the sensory defect. The hand, therefore, will always be merely a helping hand, even though its gross function can be improved with surgical treatment. This should be made quite clear to both parents and child; the advice should not be construed as being a recommendation against surgery, but rather to make sure they understand what results can be anticipated if surgery is undertaken.
In continuing the examination of the upper limbs, move the elbow passively through flexion and extension and the forearm through pronation and supination. Restricted elbow extension with restricted supination can mean contracture of the pronator teres. Release of this muscle through surgery is indicated if the child shows any tendency for voluntary active supination of the forearm. Occasionally, elbow-flexion contractures are severe enough to merit surgical release of the elbow flexors.
Lower limbs. Examination of the lower limbs should include the hip, the knee, the tibia and fibula, the ankle, and the foot.
The hip. Abduct the hips with the hips in 90 degrees of flexion and in extension. This abduction may elicit adductor spasticity and scissoring. In a child or adolescent, abduction limited to 45 degrees or less is abnormal; in infants, abduction less than 60 degrees is abnormal.
The best test for hip-flexion contracture is to have the child lie supine on a firm table, with one hip flexed on the abdomen. The opposite hip will rise from the table in varying degrees. The angle that the femur subtends with the lumbar spine is the degree of hip-flexion contracture.
An anteroposterior radiograph of the hip should be ordered when there is either adduction or hipflexion contracture or both, and the physician should specify that the knees be held together with the patellae pointing straight up. Otherwise the x-ray technician will position the child with the hips in abduction, thus reducing the subluxation, and the report is likely to be misleading in stating that the hips show no abnormalities.
Hip internal rotation and external rotation can be measured with the patient prone by flexing the knee 90 degrees and turning the femur in and out. It is important that the examiner firmly press and hold the child's pelvis to the table with one hand while flexing the knee with the other, in order to avoid misleading pelvic rotation. If the examiner has difficulty in doing this maneuver, the mother or the nurse can hold the child's pelvis level while the hip is rotated.
The angle of rotation is measured by dropping a perpendicular down to the knee and another line along the anterior tibial shaft. The range of hip internal and external rotation is 45 to 60 degrees in children. In children who have cerebral palsy with persistent fetal femoral anteversion, hip internal rotation will be 80 to 90 degrees and external limited to 0 to 20 degrees.
The knee. With the patient still prone, flex the knee rapidly. The pelvic rise indicates spasticity of the rectus femoris and of the iliopsoas. The increased stretch reflex in the rectus femoris and quadriceps as a whole can be easily appreciated when the test is positive.
With the patient supine, measure the degree of shortening of the hamstrings by flexing the hip 90 degrees, then extending the knee to its limit. The angle formed between a line extending along the femoral shaft and the lateral side of the leg measures the degree of hamstring contracture. In normal children, this "popliteal angle" can be 0 to 20 degrees. Next, bring the lower limb down on the table; gentle pressure on the anterior aspect of the knee should allow it to straighten to the 0-degree extended position. If it cannot and remains flexed, this indicates knee-joint flexion contracture. The degree of contracture can be estimated by noting the lack in extension from the zero position.
The tibia and fibula. The twist of the tibia and fibula can be estimated by having the child seated on the examining table, with his knee flexed 90 degrees over the edge. A line is drawn through the tips of the malleoli and measured against a line through the transcondylar axis - which, for all practical purposes, can be considered as the table edge. The normal external tibiofibular torsion in infants is from 0 to 10 degrees, in children from 12 to 15 degrees. At maturity the mean external tibiofibular torsion is 23 degrees.
The ankle. Range of dorsiflexion of the ankle is checked with the patient's knee extended. It is important to hold the hindfoot in varus to avoid concomitant dorsiflexion at the midtarsal joints. The degree of limitation of dorsiflexion from the zero position indicates an equinus deformity. With the knee flexed 90 degrees, the ankle is again dorsiflexed to determine whether the dorsiflexion range improves dramatically on this maneuver. If it does, this may indicate a contracture of a gastrocnemius alone and not of the soleus muscle.
With the knee extended, ask the patient to dorsiflex the ankle. This gives an idea of the amount of voluntary control of muscle function.
The "flexor withdrawal reflex" is an additional test that is positive only when there are uppermotor-neuron lesions. In this test, ask the child to flex his knee 90 degrees, and then flex his hip against resistance of your hand on the anterior aspect of the distal femur. If there is spastic paralysis, automatic dorsiflexion of the foot will occur.
If the patient can stand, the position of the hindfoot is first noted. Eversion of the heel beyond the neutral position when the heel is bisected and measured against the tibial shaft describes the valgus position. Similarly, the inversion or varus of a hindfoot can be measured.
The foot. Forefoot pronation or supination is looked for. With pronation the foot looks flat; with supination the arch appears high, and the heel rolled inward. Hallux valgus is common in children with spastic pes valgus. Toe-flexion deformities will usually be obvious when the patient stands.
Estimate the mobility of the foot in inversion and eversion by having the patient sit on the examining table, with his knee flexed 90 degrees over the edge. Resistance to inversion indicates spasticity of the peroneal muscle. Resistance to eversion indicates spasticity of the posterior tibial and, at times, the anterior tibial muscle. Then extend the knee and look at the plantar aspect of the foot. The central axis of the heel is "eyeballed" by drawing a line through the center of the heel, which in effect is the major axis of the weight-bearing ellipse of the heel. This line can be constructed with a ruler placed on the central axis of the heel. Normally, the line will pass through the second and third toes. If you see it pass through the third and fourth toes, there is moderate metatarsus adductus. If the line passes through the fourth and fifth toes, the metatarsus adductus is severe.
OTHER AIDS TO ASSESSMENT
The physical therapist can greatly assist the physician in assessing the patient by documenting on flow sheets the motor development, the equilibrium reactions, the ranges of joint motion, and the extent of voluntary control of muscles. The occupational therapists can do a similar service with assessment of the upper limbs and the activities of daily living. Assessment forms have been published.
Electromyographic examinations during gait are becoming more and more feasible, and a number of centers have such laboratories. These assist the surgeon in defining the location and extent of the muscle spasticity so that more rational judgments may be made for specific surgery. Various methods of objectively measuring the ranges of motion of joints during gait have been developed and are now being used in various motion-analysis laboratories.
Occasionally, and when in doubt about the effects of surgical treatment, myoneural 45 per cent alcohol blocks of the gastrocnemii and the hip adductors have proved to be useful. The blocks are given under brief general anesthesia. The duration of such blocks' eliminating the muscle spasticity' is between two and six weeks. This gives the patient, the physical therapist, the family, and the surgeon an opportunity to observe the results of proposed surgery at these levels. Children over the age of 10 years may be receptive to myoneural or nerve blocks with a local anesthetic as part of the evaluation. Such blocks have been particularly useful in evaluating the desirability of surgery in the upper limb.
The objectives of orthopedic surgery are (1), to prevent serious structural deformities that will preclude maximum independence in adult life and (2), to improve function and appearance in gait, and of the upper limb in hemiplegic children. Timing of orthopedic surgery. I generally recommend avoiding orthopedic surgery in children of preschool age unless there has been a structural change, particularly in the hip. When radiographs of the pelvis and hip show subluxation, a child almost always needs release of either the hip adductor muscles or of the iliopsoas or both, regardless of his age. Long-term results of adductor myotomy, anterior-branch-obturator neurectomy and iliopsoas tenotomy have shown that they are an excellent preventive for subluxation and dislocation.
Occasionally, severely spastic children will be prevented from standing in the preschool years because they have developed a flexion contracture of the hips, knees, and often the gastrocnemiussoleus muscle. In such cases, surgery to relieve the contractures can be justified. For functional and cosmetic improvement, however, I prefer to wait until the child is ambulatory. Most of the children who are going to walk independently or with crutches will do so by the age of four years, and no later than seven years.
The question is sometimes asked if there are any indications for epiphyseal arrest, particularly in hemiplegics. Epiphyseal arrest of the distal femoral epiphysis of the long limb is indicated only if the leg length discrepancy exceeds 2 cm. The arrest must be timed according to the anticipated remaining growth calculated to the skeletal age of the child.
The best results in surgery for the prevention of later structural deformities and for functional improvement have been in children between the ages of five and seven years. An exception to this rule would be the subtalar extra-articular arthrodesis (Grice) which is fraught with many complications and failures before the age of seven years. Despite the risk inherent in generalizations, I suggest the pediatrician strive to wrap up all orthopedic treatment by the time the child is eight, so that he can get on with becoming a "whole person." Any treatment after this age should be strictly shortterm and incidental.
It is well known that children do not appreciate (or participate in) repetitious exercise routines after they have reached the age of seven or eight. At these ages, play and social activities become of overriding importance. In fact, once the child is out in the neighborhood playing with his peers or playing in the playground at school, this is the therapy.
Physical therapy in our 550 cerebral-palsy patients who have had surgical treatment has lasted for a mean of six months after surgery (ranging between three and nine months).
Compensatory treatment with mobility devices, such as small portable electric wheelchairs, has allowed for growth and development in children who are nonambulatory (in our patient population, approximately 22 per cent).
Orthotic and motility aids. In contrast to the situation that prevailed 25 years ago and earlier, when cerebral-palsy programs were first getting started, today we no longer use full-control metallic braces for children with the disorder. Instead, we are more selective.
The fact is that no orthosis will control or prevent hip abduction or flexion contracture. There are none that will prevent subluxation or dislocation of the hip. Occasionally we have used a hipadduction orthosis on a small child who is beginning to walk and has some mild adductor spasticity, not to a degree to which surgical release would be justified. In such cases the orthosis is constructed of a pelvic band, with small thigh cuffs and adjustable hip joints.
The plastic ankle-foot orthosis worn over the sock and in an ordinary shoe has been helpful (but not always curative) for children who have a dynamic equinus and who are beginning to walk. If the orthosis is used when there is a definite contracture of the gastrocnemius soleus, it will not be comfortable because the heel will ride up inside the orthosis. A blister will soon evolve. When contracture is present, surgical lengthening of the Achilles tendon or gastrocnemius-soleus complex is indicated.
Orthopedic shoes do little except hide the child's deformity. The problem of the corrective high-top shoe is that it tends to make both parents and children delay seeking necessary treatment. As Perry1 has noted, "If you don't see it, it is not there."
A plastic ankle-foot orthosis to hold the foot in the corrected position is sometimes helpful for children with pes valgus and varus, provided that the deformity is not fixed and spasticity is not too great. The most successful and easiest operation in pes varus is to lengthen the posterior tibial tendon. Unfortunately, pes valgus has not responded well to lengthening of the peroneal tendons, and late varus may result when this is attempted.
When the child's knee flexion posture is greater than 15 degrees, plastic ankle-foot orthoses with locked side joints at the knee may be used temporarily or postoperatively until sufficient quadriceps strength has been gained.
Scoliosis may be held and prevented from increasing with the early application of plastic spinal orthoses.* At times, such orthotics are not tolerated well by totally involved patients who sit in wheelchairs. In these cases we build in a correction into the molded seat insert for the wheelchair.
In the upper limb, plastic night splints are used in the attempt to prevent flexion contractures of the fingers and wrist flexor and adduction contracture of the thumb. We have found hand orthoses to be totally unsuccessful in treating a child during the day, since they make it impossible for him to make any functional use of his hands.
A walker is essential for children who have poor balance when pushed, either from front to rear or from side to side. Walkers should be used if all other signs of walking are good. If the equilibrium signs are good only from side to side but not from front to rear, the child will need crutches for walking. The child who lacks only posterior balance (that is, he falls backwards only when pushed from the front) usually can walk without any external aids.
We recommend the early use of wheelchairs for those children who cannot walk functionally. If both upper limbs are good, children can handle manual wheelchairs without excessive energy consumption. If only one hand is good, I now prescribe a portable electric child-size wheelchair. A variety of interfaces and controls can be installed so that a child with cerebral palsy can use such a chair even if he does not have accurate digital motion and coordination.
Seat inserts and specialized commercial chairs are essential for children who do not have truncal balance. It will be impossible for a child to get maximum functional use of his hands if he must constantly use his upper limbs to balance himself when seated.
Space limitations prevent a discussion of home and school programs for physical therapy, occupational therapy, etc., but those interested in more information on the subject are referred to the bibliography.2
Pediatricians can help their cerebral-palsy patients by performing the type of musculoskeletal examination described above, so that referral can be made when necessary before irreversible structural changes occur.
Orthopedic surgery is only an incident in the overall management of the child with cerebral palsy, and it must be linked to the goal of all management: maximum independence in adult life.
The child's intensive-treatment program should be completed by the time he is eight years old if at all possible, so that he can be integrated into the community in as normal a manner as his condition allows. Once the intensive-treatment program has ended, the permanently handicapped child's medical care becomes only incidental, and a personal responsibility, as it should be for all other children.
1. Perry, J. Personal Communication.
2. Bleck, E. E. Orthopaedic Management of Cerebral Palsy. Philadelphia: W. B. Saunders Company, 1979.
Bleck, E. E., and Nagel, D. A. Physically Handicapped Children: A Medical Atlas for Teachers. New York: Grune & Stratton, 1975.
Samilson, R. A. (ed.). Orthopaedic Aspects of Cerebral Palsy. Philadelphia: J. B. Lippincott Company, 1975.
Sharrard, W. J. W. Paediatric Orthopaedics & Fractures. Oxford, England: Blackwell Scientific Publications, 1971.
Tachdjian, M. O. Pediatric Orthopedics. Philadelphia: W. B. Saunders Company, 1972.