Choksi, Ankita PT, MS; Townsend, Elise L. DPT, PhD, PCS; Dumas, Helene M. PT, MS; Haley, Stephen M. PT, PhD, FAPTA
Spinal cord injury (SCI) affects 2 per 100,000 U.S. children each year and results in temporary or permanent sensory and/or motor deficits, as well as short- and/or long-term changes in functional abilities, including mobility and activities of daily living (ADL).1 Absence of motor and sensory function below the level of lesion is known as complete SCI, whereas partial preservation of motor and/or sensory function is considered as incomplete injury.2 Both complete and incomplete SCI can result from traumatic events such as motor vehicle accidents, falls, and firearm or sports-related injuries.1 Nontraumatic etiologies include tumors, spinal fusions, skeletal dysplasias, juvenile rheumatoid arthritis, SCI without radiographic abnormality, syringomyelia, and transverse myelitis.3 Severity of disability associated with pediatric SCI depends on the completeness of the lesion and on the spinal level, both of which affect neurologic recovery4–6 and functional outcomes.7–9 Given the impairments in body structure and function, activity limitations and participation restrictions that occur after SCI, inpatient physical rehabilitation is a standard of care along the continuum of postinjury management.
Advances in emergency medical care and acute rehabilitation have led to higher survival rates in children with SCI.10 As a result, a better understanding of neurologic and functional recovery has become increasingly important. Evidence suggests that 10% to 26% of children who survive after a complete SCI show neurologic recovery in level of injury across subsequent months as swelling becomes reduced and healing occurs, although recovery seems to be limited to 1 to 2 spinal levels.4–6 In contrast, 74% to 89% of children with incomplete SCI show improvement in the level of injury, of which 60% to 80% recover full neurologic function and 20% to 40% improve by 1 to 2 levels after either conservative or surgical intervention.4,5
Fortunately, pediatric SCI is a relatively rare condition seen in children's rehabilitation centers. Thus, there is a paucity of studies of functional recovery using recommended standardized outcome measures. Children with SCI have been reported to exhibit functional gains in ambulation, functional mobility, and ADL after SCI.7–9 Two reports have identified significant improvements in functional mobility and ADL among children with SCI across an inpatient rehabilitation stay.8,9 Both studies used the Functional Independence Measure for Children (WeeFIM) as the primary outcome variable. One limitation of these studies is that the WeeFIM measures only burden of care in terms of the amount of assistance needed to perform a limited repertoire of functional activities and does not measure the children's ability (or inability) to master functional skills across levels of difficulty.
Comprehensive standardized functional outcome measures are needed to evaluate children with disabilities to provide evidence supporting the effectiveness of pediatric rehabilitation.11 The Pediatric Evaluation of Disability Inventory (PEDI) is one such standardized functional assessment tool that identifies the extent and areas of functional deficit or delay and may be used to detect changes in functional recovery over time. The PEDI is an easy-to-administer tool appropriate for use for children between the ages of 6 months and 7.5 years and for older children whose functional abilities are at or below 7.5 years.12
The primary purpose of this study was to describe functional recovery in mobility and self-care for a sample of children with SCI across an inpatient rehabilitation stay using the PEDI. We also sought to identify the specific areas of mobility and self-care that showed greatest improvement during inpatient physical rehabilitation. We used a similar approach to that of Tokcan et al,13 who described outcomes of children with brain injury at the total score and item-group level of the PEDI. A secondary purpose was to identify how injury variables, including age at injury, level of injury (cervical or thoracolumbar), cause of injury (traumatic or nontraumatic), and completeness of injury (complete or incomplete) relate to functional changes in mobility and self-care during an inpatient rehabilitation stay.
The sample consisted of 32 children and adolescents with SCI (mean age, 10.6 ± 6.2 years; range, 1–19 years) admitted to the inpatient physical rehabilitation program at Franciscan Hospital for Children between 1995 and 2007. Data were collected only for a first admission to the rehabilitation program after an acute care hospital stay in a local or regional facility. Children with concomitant brain injury were excluded. The institutional review boards at Franciscan Hospital for Children and Spaulding Rehabilitation Hospital approved this study.
Inpatient Rehabilitation Program
Children and adolescents admitted to the inpatient rehabilitation program at Franciscan Hospital for Children are deemed medically stable and demonstrate a prognosis for improvement in the areas of mobility and self-care. Children typically receive therapy services for a minimum of 3 hours per day, including individual physical therapy and occupational therapy. The treatment team at Franciscan Hospital for Children includes a pediatric physiatrist, rehabilitation nurse, physical therapist, occupational therapist, therapeutic recreation specialist, teacher, dietitian, school liaison, social worker, and case manager. The physical and occupational therapists work closely with the child, family, and health care team to develop and implement a comprehensive therapy program based on the identified individual needs of the child. Throughout the child's stay, safety, family training, and equipment needs are addressed. In addition, home visits and community reintegration activities are incorporated into the child's plan of care, when appropriate, to best prepare the child and family for return to their home community.
Children's functional abilities were measured at admission and discharge using 2 of the 3 content domains of the PEDI: mobility and self-care. Within each of these 2 domains, children's abilities can be assessed using the Functional Skills (FS) and Caregiver Assistance (CA) scales. The mobility domain content includes transfer skills, locomotion, and stairs measured with 59 individual FS scale items, divided into 13-item groups, and 7 individual CA items. The self-care domain content includes eating, tooth and hair brushing, nose care, washing, dressing and toileting measured with 73 individual FS items, divided into 15-item groups, and 8 individual CA items.
The FS scale identifies discrete functional activities for which children demonstrate mastery and competence, scored as “unable/limited in capability to perform the item in most situations” (score 0) or “capable/independent of performing the item in most situations” (score 1). The CA scale identifies the amount of CA provided to children during complex functional activities based on a 6-point ordinal scale (0–5), where a score of 0 indicates total assistance; 1, maximal assistance; 2, moderate assistance; 3, minimal assistance; 4, supervise/prompt/monitor; and 5, independent. The point values for each item are summed to determine a raw score for each scale. Raw scores are then transformed to scaled scores using the tables in the PEDI manual.12
Studies of psychometric properties of the PEDI suggest high internal consistency,12 moderate to high inter-interviewer reliability,12,14,15 excellent intrarater reliability,14,15 and concurrent validity with a variety of standardized pediatric instruments such as the Battelle Developmental Inventory Screening Test,16 the Peabody Developmental Motor Scales,15 the Gross Motor Functional Measure,14 the Melbourne Assessment of Unilateral Upper Limb Function,17 the WeeFIM,18 and the Pediatric Outcomes Data Collection Instrument.19 Moreover, the PEDI effectively discriminates between children with and without disabilities.12,16 It is a responsive tool that can detect changes in functional abilities and performance over time in children with a wide variety of disabling conditions and across different settings, including inpatient rehabilitation.20–22 Hence, the PEDI is a potentially useful tool for measuring functional improvement in children with SCI.
Retrospective review of medical records was performed for 32 children with SCI who were identified from a hospital database and met the inclusion criteria. Children's age at injury, gender, ethnicity, cause of injury (traumatic or nontraumatic), level of injury (cervical or thoracolumbar), completeness of injury (complete or incomplete), length of stay in acute care, and length of stay in inpatient rehabilitation were identified and recorded. For grouping by neurologic level of injury, children with C1-C8 level of injury were classified as cervical SCI and those with T1-S5 level injury were considered thoracolumbar SCI.23 If questions about the medical record data arose, they were resolved with hospital personnel. Data entry was performed by the first author (A.C.) and verified by a co-investigator (H.M.D.).
The PEDI mobility and self-care domains are routinely administered to all children with SCI on admission and discharge from the inpatient rehabilitation program. Therapists are trained in administration of the PEDI in clinical practice by instructional videos, training sessions, and completion of case studies from the manual. The mobility domain was administered by physical therapists, and the self-care domain was administered by occupational therapists. The social function domain of the PEDI is not routinely administered for children with SCI in the Franciscan Hospital for Children's inpatient rehabilitation program and was not included.
Raw scores for each of the scales (FS and CA) and domains (mobility and self-care) were identified from each patient's admission and discharge PEDI records. Raw scores were then transformed into scaled scores (0–100) using Appendix VII of the PEDI manual.12 These scaled scores were used as primary outcome variables. Mobility domain scaled scores at admission and discharge were available for all 32 subjects. Self-care domain discharge scores were missing for 6 of the 32 subjects, leaving complete data from 26 for primary analyses after listwise deletion.
To examine change in specific areas of function from admission to discharge, FS scale item-group scores were calculated by summing the individual item scores within task-specific groups. For example, in the FS scale of the mobility domain, the 4 individual items related to transferring in and out of bed were added together to create the item-group of “bed mobility/transfers.” In total, 13 item-group scores were created for the mobility domain and 15 for the self-care domain. These item-group scores, along with CA scale individual item scores, were used as secondary outcome variables to examine specific areas of recovery. In the mobility domain, FS individual item-group and CA individual item scores were not available for 11 of 32 subjects. In the self-care domain, FS individual item-group scores were not available for 12 of 26 subjects and CA individual item scores were not available for 11 of 26 subjects. Therefore, FS individual item-group and CA individual item scores from 21 subjects for the mobility domain, and from 14 and 15 subjects, respectively, for the self-care domain were used in secondary analyses.
Descriptive statistics were used to evaluate demographic information. Paired t tests were performed to compare admission and discharge PEDI scaled scores for the 2 domains and 2 scales. Significance level was adjusted for multiple tests. Effect sizes were calculated by dividing the mean change scores for each domain and scale by the standard deviation of admission scores. Interpretation of effect sizes was based on Cohen's criteria, whereby an effect of less than 0.4 is considered small, 0.5 is considered moderate, and above 0.8 is considered large.24 Chi-square analyses were conducted to compare demographic characteristics of the samples of subjects with and without individual FS item group and individual CA item data. A Wilcoxon signed rank test was conducted to compare the admission and discharge change scores within the PEDI individual item group and item scores. Spearman rank correlation analyses were used to examine the relationships between admission to discharge change scores and (1) age at injury, (2) level of injury (cervical or thoracolumbar), (3) cause (traumatic or nontraumatic), and (4) completeness of injury (complete or incomplete). The SPSS version 15.0 (SPSS Inc., Chicago, Illinois) was used for data management and statistical analysis.
Demographic features of the sample are presented in Table 1. Eighteen children (56%) had a cervical injury and 14 (44%) had a thoracolumbar injury. Classification according to cause of injury showed that 24 children (75%) had sustained a traumatic SCI and 8 (25%) had sustained a nontraumatic SCI. The traumatic causes included motor vehicle accidents (38%), gunshot injuries (19%), falls (13%), and diving injuries (6%). Nontraumatic causes included tumors (13%) and arteriovenous malformations or other ischemic events (13%). Fifty-nine percent of the children sustained an incomplete SCI; the remaining 41% had a complete injury. The average length of inpatient rehabilitation stay was 168 days (SD = 231 days), and 91% of the total sample was discharged home at the end of the rehabilitation stay.
The mean changes in PEDI scaled scores are presented in Table 2. Overall, children with SCI demonstrated significant improvements on the FS scale for both the mobility and self-care domains (mobility: t31 = 9.22, P < .001; self-care: t25 = 5.35, P < .001). A significant reduction in CA required in the mobility and the self-care domains was also evident (mobility: t31 = 6.88, P < .01; self-care: t25 = 5.12, P < .01). Effect sizes for the total sample ranged from 0.74 to 1.03 for both domains and scales.
Chi-square analysis showed that the demographic features for groups of children with and without individual FS item group and individual CA item scores did not vary significantly from one another in terms of age at injury (mobility: t30 = 0.39, P = .70; self-care: t30 = 0.21, P = .83), gender (mobility: χ2 = 1.33, P = .25; self-care: χ2 = 1.56, P = .21), level of injury (mobility: χ2 = 0.80, P = .37; self-care: χ2 = 1.81, P = .18), cause of injury (mobility: χ2 = 1.15, P = .28; self-care: χ2 = 1.52, P = .22), and completeness of injury (mobility: χ2 = 0.13, P = .72; self-care: χ2 = 0.05, P = .82).
The individual FS item group and individual CA item admission to discharge change scores of mobility and self-care domains are presented in Tables 3 and 4. The sample improved significantly in all the FS item group and CA item scores in the mobility domain except for the outdoor locomotion FS item-group (Z = 1.00, P = .32) and the stairs CA item (Z = 1.84, P = .07). The sample also showed significant improvement in a majority of the individual FS item-group (9/15) and individual CA item (7/8) scores in the self-care domain, except for food textures (Z = 1.63, P = .10), tooth brushing (Z = 1.63, P = .10), hair brushing (Z = 1.79, P = .07), nose care (Z = 1.90, P = .06), hand washing (Z = 1.90, P = .06), and fasteners (Z = 1.49, P = .14) FS item-groups and bladder management in the individual CA items (Z = 1.84, P = .07). Across both mobility and self-care domains, performance of all but 1 child either improved or remained the same, as demonstrated by the positive ranks and ties for individual item groups and individual items, respectively (Tables 3 and 4). Only 1 child showed a decrease in performance across both domains and scales, as evidenced by negative ranks.
Analyses of the relationships between injury variables and functional outcomes revealed that completeness of injury was positively associated with CA self-care scores (r = 0.57, P < .01), such that those with incomplete injury gained more independence in self-care than those with complete injury. Age at injury, level of injury (cervical or thoracolumbar), and cause of injury (traumatic or nontraumatic) were not significantly correlated with PEDI change scores for the FS/CA scales for either the self-care or mobility domains.
Overall, children with SCI demonstrated functional recovery in mobility and self-care from admission to discharge during an inpatient rehabilitation stay. The children showed both improvement in FS and reduction in CA across mobility and self-care domains as measured by the PEDI. These findings are consistent with previous studies by Garcia et al8 and Allen et al,9 which reported significant improvement in functional status of children with SCI after inpatient rehabilitation, as measured by reduced level of assistance on the WeeFIM.
The individual FS item group and individual CA item analyses showed that children with SCI improved in nearly all mobility FS item-groups and CA items of the PEDI, including toilet transfers, chair or wheelchair transfers, car transfers, bed mobility, tub transfers, indoor locomotion, and stairs. Children's improvement varied for outdoor locomotion. Although significant improvement was noted for the FS item-group outdoor locomotion–distance/speed, no significant change was noted for the FS item-group outdoor locomotion methods, which includes the following 2 items: (1) walks but holds onto objects, caregivers, or devices for support and (2) walks without support. One possible explanation for lack of improvement in this item-group relates to test item sensitivity for children with SCI. To show improvement in the outdoor locomotion methods item-group, children would have to walk independently without devices or assistance. This degree of independence may not be realistic after SCI, particularly if the injury is complete or at a high neurologic level. Sixty percent of the sample scored 0 (unable) at both admission and discharge for this item-group, which likely carried the negative effect. Children with SCI improved in the FS item- group of stair mobility; however, they did not improve in the amount of CA required during stairs. This means that even though children gained capability with stair mobility skills, this improvement did not translate into a reduction in CA in day-to-day stair activities. More than three-fourths of the sample began and ended rehabilitation with a score of 0, complete dependence, suggesting that this item exhibited a large floor effect, not entirely surprising in an inpatient environment.
Children with SCI also improved in many self-care FS item-groups of the PEDI, including use of utensils, use of drinking containers, washing body and face, wearing front opening garments, pants, shoes/socks, toileting tasks, and bladder/bowel management. However, children did not improve in the self-care item groups of food textures, tooth brushing, hair brushing, nose care, hand washing, and fasteners. A review of admission and discharge individual FS item-group scores revealed that for the food texture item- group, which includes the type and texture of food consumed by the child, 70% of subjects scored the maximum of 4 at both admission and discharge. Thus, lack of overall group change in food texture may be attributable to ceiling effects. For the other self-care item-groups with no significant change, 43% (6/14) of children had the same scores at admission and discharge, 43% (6/14) improved by 1 or more levels in all 5 item-groups and 14% (2/14) showed a decline in FS at discharge. Of the 6 subjects who showed no change, 5 had thoracic SCI with scores of 4 or 5 across all 5 fine motor item-groups and 1 had a cervical SCI with a score of 0 at admission and discharge. In contrast to those with thoracic injury, children with high cervical SCI (C1-C5) generally have difficulty performing the self-care activities that involve controlled upper extremity and hand movement, such as eating, grooming, and bathing.25 Thus, we saw a floor effect for some fine motor self-care items in those with cervical SCI, alongside a ceiling effect in those with thoracic SCI. Future studies should aim for larger group sizes to allow separate statistical comparison of cervical and thoracic level groups.
Of the 43% of children who showed improved self-care FS item-groups scores from admission to discharge, 65% (4/6) were older than 10 years and improved by 1 to 5 points, whereas the others were younger than 3 years and improved by just 1 point. The 14% (2/14) of children who showed a decrease in self-care FS scores after rehabilitation were also younger than 4 years. Importantly, rehabilitation goals for younger children may not have focused on tooth brushing, hair brushing, nose care, hand washing, and fasteners because these are skills not often mastered by children younger than 3 years. Indeed, children younger than 5 years typically require assistance for these kinds of fine motor self-care activities and, with emphasis on other aspects of rehabilitation as an inpatient, may become more dependent on caregivers after injury. Individual patient rehabilitation goals and interventions were not examined as part of this study, limiting the ability to draw specific conclusions about the relevance of task-specific training to study findings. Regardless, this study adds to the existing literature on functional recovery in children with SCI during inpatient rehabilitation. Similar analyses may be useful in future studies to compare outcomes of particular interventions directed at specific functional abilities.
With the exception of completeness of injury and CA self-care scaled scores, injury variables and PEDI change scores were not correlated in this sample. These findings are consistent with those of Garcia et al,8 who reported similar findings from a single site with a diverse pediatric SCI sample using the WeeFIM. However, Allen et al,9 in a multisite study, found that neurologic level of injury and cause of injury predicted functional improvement as measured with the WeeFIM in children with SCI. Multisite studies with larger samples are more likely to identify relationships among injury variables than smaller single-site follow-up studies, given improved power.
We note a number of limitations in this study. First, the sample size was relatively small. Although power analyses for t tests showed robust power (99%), analyses for correlations showed power in the 8% to 37% range for all analyses except one (83%). These findings suggest that a sample size of at least 85 subjects would have been necessary to achieve an α level of .05 and 80% power for a correlation of 0.30 to detect significant relationships between recovery and injury variables such as level, cause, and completeness of injury. Thus, the lack of significant findings in the correlational analyses may be attributable to limited power. Second, this single-site study may not have provided a sample that is truly representative of the larger population of children with SCI. In the general population, 30% of children with SCI have incomplete SCI and 70% have complete injury.26 Our sample consisted of equal proportions of complete and incomplete injury, overrepresenting incomplete SCI, and perhaps enhancing the ability to detect functional recovery. Third, data for this retrospective study were collected over a 12-year period during which multiple physical therapists and occupational therapists may have administered the PEDI. Reliability data were not collected. Information about patients' rehabilitation intervention related to mobility and self-care that children received as part of an inpatient rehabilitation stay was not able to be included, given lack of availability and consistency of documentation. To evaluate how rehabilitation interventions, including elements of task-specific training, relate to improvement in mobility and self-care as measured by the PEDI, more detailed information about physical and occupational therapy services would need to be collected. Continued study using a prospective design that plans for and clearly defines intervention variables would be useful.
This study demonstrates that the PEDI can be used to provide meaningful information about collective and specific functional abilities, and improvement over time, in children with SCI. Compared with the WeeFIM, which indexes only burden of care, the PEDI measures both caregiver assistance and actual functional performance, providing richer information for assessing rehabilitation outcomes in children. However, to our knowledge, few rehabilitation centers caring for children with SCI currently use the PEDI to quantify functional changes with physical therapy and occupational therapy intervention. Given the documented responsiveness of the PEDI, both here in children with SCI and previously in children with traumatic brain injury,27 osteogenesis imperfecta,28 Down syndrome,29 spina bifida,30 and cerebral palsy,31 consideration of broader use is warranted.
Children with SCI showed improved functional skills and reduced the need for caregiver assistance as measured by the PEDI during inpatient rehabilitation. An analysis of both PEDI summary scores and scores for specific areas of function identified mobility and self-care skills that show improvement in children with SCI after inpatient rehabilitation. These findings can be used by clinicians to guide goal setting, intervention, plan of care, and prognosis. Further research should be directed at establishing reliability, validity and minimal clinically important difference, or minimally important difference of the PEDI with this population of children. Also, studies using PEDI and other functional measures would be helpful to compare the psychometric properties and clinical usefulness of different outcome measures. Finally, a prospective study that also examines the effects of specific therapeutic interventions would be useful in maximizing rehabilitation outcomes of children with SCI.
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