Factors predicting postoperative complications following spinal fusions in children with cerebral palsy

A retrospective review of 107 patients with cerebral palsy who had undergone a posterior spinal fusion with unit rod instrumentation by the same two surgeons was done to determine what factors cause complications that lead to delayed recovery time and a longer than average hospital stay. The operative risk score was developed with scores for the child's ability to walk and talk, oral feeding ability, cognitive ability, and medical problems within the year prior to surgery. Operative risk score is primarily a measure of degree of neurologic involvement. The postoperative complication score (POCS) is a combined measure of all postoperative complications including factors for prolonged intubation, intensive care unit stay, hospital stay, and delayed feeding. The mean age at surgery was 14.3 years. The mean weight was 29.5 kg, with 89 of 107 patients below the fifth percentile for weight compared with age. The mean degree of spinal deformity was 75.2 degrees (range 43-120 degrees ). The mean weight for age was -1.96 SD below the normal. The mean operative time was 4.3 h, with estimated blood loss of 1.2 blood volumes. The mean length of hospitalization was 23 days 2 h, with 5 days 2 h in the intensive care unit. The operative risk score and weight for chronological age below the fifth percentile showed statistical significance (p = 0.05) in regard to increased POCS. The weight for height-age and deficient total lymphocyte count, both factors that measure nutritional status, showed no statistical significance (p > 0.05) compared with POCS. Curves with deformity of >70 degrees had statistically significant high POCS (p = 0.03). Complications for patients having a posterior and an anterior surgery versus those who had a posterior fusion alone were not statistically different (p > 0.05). The factors that led to a greater rate of complications were the severity of neurologic involvement, severity of recent history of significant medical problems, and severity of scoliosis.

Muscle-tendon surgery in diplegic cerebral palsy: functional and mechanical changes

A prospective assessment of muscle-tendon (M-T) surgery was conducted on 30 patients with spastic diplegia. Muscle-tendon surgery consisted of recessions or releases to improve gait function by correcting restricted joint motion and joint malalignment. Functional-outcome measures included the Gross Motor Function Measure (GMFM) and temporal gait factors. Kinematic gait data were evaluated to determine the mechanical effects. The mean age at surgery was 8.7 years (4-20 years), and 3.5 muscle tendon units per extremity were recessed or released at surgery. The primary kinematic change for the hip and the knee was a shift in the sagittal joint position with minimal effects on overall excursion. Changes in ankle-joint dynamics after gastrocsoleus recessions included a reduction in plantarflexion and a shift in the timing of maximal dorsiflexion to later in stance. Improvements in walking velocity and stride length were evident by 6 month after surgery. Functional changes from M-T surgery included a 25% increase in velocity and an 18% increase in stride length over preoperative values seen at 9 months after surgery. Improvements in these parameters were maintained at 2 years after surgery. The GMFM total score showed minimal change after surgery with improvements occurring primarily in the standing dimension and the walking, running, and jumping dimensions.

[A review on the treatment of spastic cerebral palsy with selective posterior rhizotomy]

OBJECTIVE

To inquire the indications, contraindications, and operative methods of the treatment of spastic cerebral palsy with selective posterior rhizotomy (SPR), and to improve the therapeutic results and decrease the incidence rate of complications.

METHODS

The documents about SPR were extensively consulted, and the mechanisms, indications, contraindications, operative methods, muscular tension changes and complications after operation were reviewed.

RESULTS

With the methods of SPR, I alpha fibers of afferent nerve were selectively amputated, reflex circle of spinal cord was locked, and the muscular tension was decreased, so myospasm was removed. The results after operation and incidence rate of complications were closely related to the indications. The therapeutic results were better when the percent of spinal nerve rhizotomy was less than 50%.

CONCLUSION

It is a good method for the treatment of spastic cerebral palsy.

Interrelationships of strength and gait before and after hamstrings lengthening

Muscle-tendon lengthenings are an essential part of the orthopaedic management of static and dynamic joint contractures associated with cerebral palsy. Although these procedures typically have a positive biomechanical effect on joint alignment, the potential negative effects of alterations in tendon length on muscle strength and gait function have not been well documented in these patients, in whom muscle weakness is a prevalent clinical symptom. The purpose of this study was to examine the change in strength values of the hamstring and quadriceps muscle groups during a 9-month postoperative period in patients who had undergone hamstring tendon lengthenings, in comparison to an operative "no hamstring surgery" control group, and to relate baseline strength and postoperative changes to gait function in these patients. Results for the "hamstring surgery" group indicated that although hamstring strength declined initially, the strength increased with time and was similar to preoperative values by 9 months. Quadriceps strength measured at 30 degrees of knee flexion increased significantly during the recovery period as a direct result of improvements in knee extension. Although hamstring surgery produced an immediate effect on passive motion and knee-joint alignment, functional improvement, as evidenced by increased stride length, was not evident until strength values approximated or exceeded preoperative values.

[Selective ventral rhizotomy for the treatment of spastic cerebral palsy]

OBJECTIVE

To understand the influence of selective ventral rhizotomy on the function of lower extremity and to investigate its effect in the treatment of spastic cerebral palsy.

METHODS

Ten domestic dogs were used in this study. Under anesthesia, the lumbar spinal canal was reached through posterior approach. The ventral rami consisted of left L5, L6 and L7 spinal nerves was separated. The electromyographic changes of each branch of the rami was examined by electrical stimulation. 60 percents of the L6 ventral nerve root which was the major innervation of the gastrocnemius muscle in dogs, and 30 percents of the other two rami were culted off. The muscle tone, the coordinated movement and balanced capacity of the dogs were observed. After one month, the electrophysiological changes of the biceps femoris, semitendinous, gastrocnemius and anterior tibial muscles were examined and compared with that of the identical muscles of the contralateral limbs.

RESULTS

Selective ventral rhizotomy was well correspondent to the innervated muscles. After operation, the coordinated movement and balanced capacity were good, but the muscle tone of the corresponding muscle was lowered. This technique was applied on 3 patients with satisfactory short-term results.

CONCLUSION

For the treatment of spastic cerebral palsy, it is worth trying the selective ventral rhizotomy.

Upper extremity surgical treatment of cerebral palsy

The purpose of this report is to review the surgical treatment of the upper extremity involved with cerebral palsy over a 25-year period and present our results with regard to changes in upper limb function. Surgical results were assessed by comparison of preoperative and postoperative levels of upper extremity functional use using a previously described 9-level scale. The effect of the following cofactors on surgical outcome were examined: type of cerebral palsy, age, voluntary control, mental impairment, sensibility, and type of surgical treatment. One hundred eighty operations representing 718 procedures in 134 patients were reviewed. Surgical treatment was based on the following principles: soft tissue releases of deforming spastic muscles, tendon transfers to augment antagonistic activity, and joint stabilization. Surgical planning was tailored to each child's particular needs. Comparison of the preoperative and postoperative 9-level functional use scores showed an average improvement of 2.6 functional levels for all patients. Patients with fair and good voluntary control had significantly greater improvement in functional use scores than those with poor voluntary control. No other statistically significant predictive cofactor was found. In selected patients with upper extremity dysfunction secondary to spastic cerebral palsy, surgical intervention improves function, as measured by the upper extremity functional use scale.

Morphological brain damage, functional disorders and the possibilities of their treatment in children with infantile cerebral palsy

Twenty-four children with infantile cerebral palsy (6 girls and 18 boys aged 3-17 years), surgically treated in the years 1993-1997, were involved in the study. Neurological-orthopaedic examinations and computer tomography (CT) of the head allowed precise diagnosis and understanding of its pathology. The group consisted of 10 patients with hemiplegia, 10 with diplegia and 4 with severe quadriplegia. In 18 children changes in the brain were largely dependent on the clinical type of paresis. In hemiparesis, unilateral changes, such as cerebral cortex atrophy with enlarged ventricles, were predominant. Diplegia cases frequently showed periventricular damage to the white matter. Brain tomography in severe quadriplegia did not always correspond to the clinical condition. CT examinations revealed no abnormalities in the brain in 6 out of 24 cases. Since the results of rehabilitation were not satisfactory, 29 surgical procedures were performed in the presented group of patients, with improved the course of therapeutic rehabilitation or nursing care in all the children.

Spontaneous ankylosis of the contralateral hip after unilateral adductor tenotomy in cerebral palsy

This is the case report of a 15-year-old black male with spastic quadriplegia cerebral palsy who developed heterotopic ossification and spontaneous ankylosis of his contralateral nonoperative hip after unilateral adductor tenotomy. To the authors' knowledge, this is the only reported case of such an occurrence. The mechanism and possible risk factors are discussed as well as management of this complication.

[Variability of the femoral head and neck antetorsion angle in ultrasonographic measurements of healthy children and in selected diseases with hip disorders treated surgically]

Changes in the angle of femoral head and neck antetorsion during childhood play an important role in the physiological development of the hip joint. In the course of some diseases the angle increases pathologically, necessitating surgical treatment. Recent technical advances have enabled the application of ultrasonography (USG) for the measurement of antetorsion angle. In this study the results of USG have been verified by comparison with results of direct measurement during varus derotational osteotomy of 163 femoral proximal ends in 104 children. Values for femoral head and neck antetorsion obtained by USG correlated closely with those obtained during surgery, justifying the use of ultrasonography for the further part of this study. An increase in antetorsion was observed in 56 joints (77%) in a group of 38 children with spastic cerebral palsy subjected to surgery. Mean angle of antetorsion was 37 degrees (SD +/- 11). The angle returned to its pre-operative values within 2-3 years from surgery. In the group of 25 children with Perthes disease, increased antetorsion was found in 11 (44%) joints subjected to surgery and in 8 (32%) normal joints. The angle changed during the observation period, confirming the opinion that the increase is a secondary event in this disease. The angle was much greater than normal for age in the group of 21 children with congenital hip dysplasia. Basing on the results of surgery it is concluded that corrective osteotomy of femoral proximal end in cases of increased antetorsion and valgity of femoral neck is not a sufficient procedure to prevent the angle from reverting to pre-operative values and should be supplemented by osteotomy of the pelvis. Furthermore, ultrasonography has emerged as the best method currently available for measurement of femoral head and neck antetorsion. The correlation coefficient for USG vs. direct (intraoperative) measurement was 0.9 in all groups, reaching 0.93 in the spastic cerebral palsy group, in which contractures and limited mobility are responsible for very low coefficients in the case of other methods. The use of USG for assessment of femoral antetorsion has revealed, particularly after longer observation periods, that the angle in the apparently normal contralateral extremity exceeded values normal for age.

Gait pattern in patients with spastic diplegic cerebral palsy who underwent staged operations

Fifteen patients with spastic diplegic cerebral palsy (CP) were monitored for a mean length of 9.5 years after they underwent staged operations and were evaluated by gait analysis, including joint motion in the sagittal plane and the ground reaction force (GRF) in three dimensions. Results showed an increased hip flexion (132%) at midstance, a reduction of peak knee flexion (PKF) during swing (45%) accompanied by an augmented time of PKF during swing (50%), and an increased dorsiflexion of the ankle during swing (293%) as well as its time during the gait cycle, in comparison with normal values. Moreover, significant decreases of the vertical GRF at the terminal stance and the forward and backward GRF were present. Additionally, it was found that a bilateral popliteal angle < 20 degrees is acceptable in spastic CP. Staged operations gave unpredictable results in the correction of contracture of the hamstrings, the Achilles tendon, and the iliopsoas. The authors are convinced that gait analysis is useful in evaluating these patients and enhances the results of operative treatment, and they have since changed their approach toward multilevel simultaneous corrections.

Epidural analgesia in children with cerebral palsy

PURPOSE

Two modalities of epidural analgesia in children with two types of cerebral palsy (CP) were compared for differences in the incidence of common complications (inadequate analgesia, hypopnea, hypoxaemia, sedation, vomiting, pruritus, urinary retention, and seizures).

METHODS

Demographic, procedural and postoperative complication data were collected on children with CP receiving epidural analgesia. Information was recorded contemporaneously with the child's care by one of the authors on 92 consecutive children with CP (age, 107 +/- 50.1 mo; weight, 26 +/- 14.2 kg) who had undergone infra-umbilical orthopaedic or Nissen fundoplication procedures between December 1994 and December 1996. The first 44 patients received intermittent bolus (IB) epidural morphine and the next 48 received continuous infusion (CI) bupivacaine and fentanyl. Two forms of CP (spastic diplegia and quadriplegia) and the two modalities of analgesia were compared.

RESULTS

Excellent analgesia was obtained in 91/92 patients. Excessive sedation occurred in six patients (6.5%) but only in IB patients, (P < 0.02 vs CI). Emesis occurred in 52% of patients, and was more common in diplegic than in quadriplegic patients (68% vs 38%, P < 0.01). Pruritus was observed in 29% of patients and was more common in diplegia than quadriplegia (48% vs 12.5%, P < 0.001). The incidences of hypopnea, hypoxaemia, urinary retention and seizures were not affected by the types of CP or analgesia and no difference in sedation was observed between spastic diplegic and quadriplegic patients.

CONCLUSIONS

Continuous infusion of epidural bupivacaine and fentanyl provided excellent analgesia for children with CP without serious complications. Intermittent bolus epidural morphine was associated with a high incidence of excessive sedation and should be avoided in this population.

[Long-term outcome of selective posterior rhizotomy for spastic cerebral palsy]

OBJECTIVE

To investigate the long term outcome and complication of selective posterior rhizotomy for spastic cerebral palsy.

METHOD

26 patients with cerebral palsy who had received SPR were followed up for four years.

RESULT

In the 9 patients who could walk and stand up from squatting position independently, 7 could stand steadily on one foot after operation. In the 12 who patients could walk and stand up from squatting position dependently, 7 could walk independently in the room after operation. In 5 patients couldn't walk and stand up from squatting position, 3 patients could walk dependently in the room after operation. Complications occurred in 3 patients.

CONCLUSION

Selective posterior rhizotomy is effective in the treatment of spastic cerebral palsy. Strictly selecting candidates for the operation and good rehabilitation training before and after operation should be emphasized for good results.

Prediction of outcome after rectus femoris surgery in cerebral palsy: the role of cocontraction of the rectus femoris and vastus lateralis

Rectus femoris surgery was performed on 70 patients with cerebral palsy and stiff-knee gait. Fifty-three patients underwent distal rectus transfer, and 17 patients had distal rectus release with complete muscle mobilization. Gait analysis was performed preoperatively and postoperatively at a minimum of 1 year. Swing-phase peak knee flexion (PKF) was improved in the transfer group, allowing improved foot clearance and more efficient gait (p = 0.04). PKF in swing deteriorated slightly in the release group (p = 0.04). The presence of abnormal swing-phase electromyogram (EMG) activity in the rectus alone or abnormal combined rectus and vastus lateralis activity did not influence the PKF results in either surgery (p < 0.05). The Ely test had no predictive value in identifying patients with abnormal EMG activity (p > 0.05). Preoperative knee range of motion was not a significant variable in determining relative success of rectus surgery. No deleterious effects were observed in stance phase in either group (p > 0.05).

Anatomical and technical considerations in surface electromyography

Despite the technical and clinical limitations of surface EMG, it is essential in the physical medicine and rehabilitation field. Surface EMG has evolved from a secondary means of clinical assessment to a primary factor in determining and predicting clinical outcomes. Computer models of electrical muscular activity are currently implemented to assist in designing proper instrumentation and electrode with optimum dimensions. These models could be expanded to simulate pathological motor functions to help understand functional abnormalities even before clinical interventions. Currently, several groups all over the world are investigating the use of multichannel surface EMG. This technological advancement would have an immediate impact on several medical fields. For instance, tendon transfers are performed to improve function in peripheral nerve injury, brachial plexus lesion, spinal cord injury, and cerebral palsy. There are potential uses for multichannel surface EMG, both preoperatively and postoperatively. Preoperatively choosing the muscle for transfer has been largely based on clinical grounds. Multichannel surface EMG could give a more objective database to assess prognosis and determine which muscle to transfer. Postoperatively, multichannel surface EMG can provide a systematic way of assessing changes in gross muscle topography caused by the tendon transfer. Other applications of multichannel surface EMG would be for bony and soft tissue deformity from arthritis, heterotopic ossification, amputation, or burns. Multichannel surface EMG would allow clinicians to get a broader picture of the skeletal muscle activity despite the fact that it is physically impossible for the patient to assume the anatomic position used for traditional isolated electrode placement. Individuals with physical disabilities that affect their ability to assume the usual posture for electrophysiologic testing may benefit considerably from development of multichannel electrophysiologic testing. Patients with abnormalities of tone from various causes such as stroke, traumatic brain injury, and cerebral palsy are at times evaluated with kinesiologic EMG to assess motor control. Multichannel surface EMG could potentially give us much greater insight into motor control disorders.

Effect of hamstring and psoas lengthening on pelvic tilt in patients with spastic diplegic cerebral palsy

The purpose of this study was to evaluate the effects of hamstring lengthenings and psoas recessions over the brim of the pelvis (OTB) on pelvic function in the gait of patients with spastic cerebral palsy. Seventy-three patients were divided into four groups based on surgical intervention: medial hamstrings (n = 37), medial and lateral hamstrings (n = 12), medial hamstrings with psoas OTB (n = 9), and medial and lateral hamstrings with psoas OTB (n = 15). Three-dimensional gait analysis was completed both before and approximately 1 year after surgery. When pelvic position in gait was normal or posterior of normal preoperatively, there was a significant increase in pelvic tilt (p < 0.05) when medial and lateral hamstrings were lengthened, irrespective of simultaneous psoas OTB surgery. Medial hamstrings alone, with or without simultaneous psoas OTB, did not result in a significant change in pelvic position, irrespective of preoperative pelvic position. The only surgical combination that caused a reduction in excessive preoperative anterior pelvic tilt was medial and lateral hamstrings with psoas OTB, a 4 degrees change of limited clinical significance. In general, psoas and medial hamstring surgery have minimal effect on the pelvic position during gait. Medial and lateral hamstring lengthening will increase pelvic tilt if preoperative pelvic position is normal or slightly posteriorly tilted. The results of this study suggest that the fundamental determinants of pelvic position during gait postoperatively are the extent of hamstring surgery (medial only vs. both medial and lateral hamstring lengthening) and the preoperative position of the pelvis.

Division of C8 nerve root for treatment of spastic cerebral palsy in the upper limbs: a preliminary report

OBJECTIVE

To investigate the effect of C8 nerve root division on the treatment of spastic cerebral palsy in the upper limbs.

METHODS

Two patients were treated with division of the C8 never root. Supraclavicular incision was made to expose the C5-T1 nerve roots. The intraoperative electromyographic recording technique was used to monitor the responses from the flexor digitorum and flexor carpi ulnaris muscle groups simultaneously. The C5-T1 nerve roots were stimulated and the evoked muscle amplitude potentials (EMAP) were recorded from the muscle groups. The EMAP of the muscle groups obtained during electrical stimulation of the C8 nerve root was the largest, which was used as the basis for C8 nerve root division.

RESULTS

Division of the C8 nerve root slightly affected the function of the upper limb, and reduced the muscle tone of the flexor wrist and digitorum.

CONCLUSION

Division of the C8 nerve root can reduce the muscle tone of the flexor wrist and digitorum in a short time. The long-term effects need to be followed up further.

Upper extremity performance and self-care skill changes in children with spastic cerebral palsy following selective posterior rhizotomy

Changes in upper extremity and self-care performance following selective posterior rhizotomy (SPR) are reported frequently, but rarely quantified. In this study, 36 children with spastic cerebral palsy were assessed preoperatively and 1 year following SPR using the Quality of Upper Extremity Skills Test (QUEST). Twenty-six children were assessed at similar intervals using the Functional Independence Measure for Children (WeeFIM) as a measure of self-care performance. Wilcoxon matched-pair signed-rank tests were used to compare the QUEST total scores and the WeeFIM motor, cognitive, and total scores before and after SPR. One year after SPR, the total QUEST scores were significantly better (median improvement = 3.2%, p < 0.0001), as were the WeeFIM motor (median improvement = 9.5, p < 0. 0001), cognitive (median improvement = 1.0, p < 0.008), and total (median improvement = 11.0, p < 0.0001) scores. The results indicate quantifiable improvements in upper extremity function, and motor and cognitive self-care skills in children 1 year after SPR.

Hand function in children with cerebral palsy after upper-limb tendon transfer and muscle release

Thirty-two children with hand dysfunction due to cerebral palsy were examined before tendon transfer and muscle release, and 9 months postoperatively. All children improved their performance regardless of the degree of impaired hand function. The main advantage of surgery was a more functional position of the hand with increased wrist extension and forearm supination. There were also increased functionality of handgrips, grip strength, and dexterity. Impaired sensibility before surgery did not influence the outcome. Individual goals were set preoperatively. Individual functional goals outlined before surgery were met by most children. Children identified as having mild impairments gained new functional skills related to everyday activity (self-care and leisure), while children with severely impaired hand function demonstrated enhanced grasping ability, as well as a better cosmetic appearance.

Microsurgical selective peripheral neurotomy in the treatment of spasticity in cerebral-palsy children

Spasticity represents the most handicapping sequelae of cerebral palsy in children. In this study, 28 children with spastic cerebral palsy were treated over the last 4 years by microsurgical selective peripheral neurotomy: 28 times the posterior tibial nerve for spastic foot deformity, 3 times the ulnar and median nerves for spastic flexion of wrist and fingers, 2 times the sciatic nerve for spastic knee flexion associated with spastic foot deformity and 3 times obturator nerves for spastic adductors. Results on spasticity with follow-up ranging from 3 to 48 months were as follows: spastic foot deformity was corrected in all patients with pure spasticity, 2 out of the 3 children with ulnar and median neurotomy improved, knee flexion and hip adduction were improved in the other 5 patients. Selective peripheral neurotomy is an effective procedure in the treatment of segmental harmful spasticity after failure of a well-conducted conservative treatment associating physiotherapy and antispasmodic medications. It must be performed before the fixed deformities and other orthopedic complications arise.

Selective dorsal rhizotomy in children with cerebral palsy. Results in 18 cases at one year postoperatively

OBJECTIVE

Effects of selective dorsal rhizotomy (SDR) were studied in children with spastic cerebral palsy in orthopaedic and functional fields.

METHODS

In a prospective study, we compared the same population before SDR and 1 year after SDR. This population included children with spastic cerebral palsy, when spasticity was responsible for a halt in the motor skill acquisitions or for orthopaedic complications. All the children had intensive physiotherapy for 6 months postoperatively. We observed spasticity by a 4-point scale, isolation of movement by a 3-point scale, and orthopaedic status by the measure of range of motion, hip migration on the radiography, and function by Gross Motor Function Measure (GMFM) and Abbott scale. All the assessments were done by the same physiotherapist. We compared the results with a Wilcoxon statistic test.

RESULTS

18 quadriplegic children had spastic cerebral palsy; their mean age was 9 years (5.5-16.5 years). We observed a decrease in spasticity in all the muscular groups; increase in range of motion only on abduction and extension of the hips; no evolution of hip migration; an increase of 3.2% in the total GMFM score; 1 child was classified IV before SDR and V after SDR on the Abbott scale; 3 children had planned orthopaedic surgery in the year after SDR; 16 children and their families were highly satisfied with the result of the surgery.

CONCLUSIONS

The decrease in spasticity does not entail prevention of orthopaedic problems in children with quadriplegic spastic cerebral palsy. However, we observed an improvement in qualitative function that is outside the scope of current assessment scales.

Somatosensory evoked potentials following functional posterior rhizotomy in spastic children

Ten children with cerebral palsy and severe lower limb spasticity were treated by functional posterior rhizotomy (FPR). Somatosensory evoked potential recordings were performed preoperatively, intraoperatively (directly on the surface of the spinal cord) and 6 months after surgery, to evaluate the effects of FPR on lower limb somatosensory function. Before surgery, 7/10 patients showed abnormal cortical responses after tibial stimulation. In all patients, intraoperative recordings showed a reduction in the amplitude of segmental responses (N22) (50 +/- 25% of reference value) after the section of a mean 50% of L2-S2 dorsal rootlets. The modifications of segmental responses (N22) were maintained 6 months after surgery, whereas reduction of cortical responses (P39) did not reach the significance level when compared with preoperative recordings.

MRI-guided stereotactic thalamotomy for cerebral palsy patients with mixed dyskinesia

The author has performed 108 stereotactic thalamotomies using MRI (MGSTs) without ventriculography in 77 cerebral palsy (CP) patients with dyskinesia(s) from January 1992 to January 1997. The clinical results were verified in terms of improvement of major preoperative symptom and patient's (or relative's) satisfaction using pre- and postoperative video recording and simple questionnaires. The results were as follows: excellent in 12 MGSTs, good in 69 and fair in 27. Postoperative morbidity was transient in all patients except for 2. Recurrences were noted in 6 MGSTs (5.6%). There was no death. MGST is thus a beneficial procedure for reducing dyskinetic symptom(s) of CP patients.