Foot and lower leg pain in children and adults with cerebral palsy: a population-based register study on 5,122 individuals.

BACKGROUND: Pain is common in individuals with cerebral palsy (CP) and the most reported pain site is the foot/lower leg. We analyzed the prevalence of pain in the foot/lower leg and the associations with age, sex, gross motor function, and clinical findings in individuals with CP. METHOD: This was a cross-sectional register-study, based on data reported to the Swedish Cerebral Palsy Follow-up Program (CPUP). All participants in CPUP, four years-of-age or older, were included. Pearson chi-square tests and logistic regression were used to analyze the prevalence and degree of pain in the foot/lower leg. RESULTS: In total, 5,122 individuals were included from the CPUP database: 58% were males and 66% were under 18 years-of-age. Overall, 1,077 (21%) reported pain in the foot/lower leg. The odds ratios (ORs) of pain were higher in females (OR 1.31, 95% confidence interval (CI) 1.13-1.53), individuals who could ambulate (Gross Motor Function Classification System Level I (OR 1.84, CI 1.32-2.57) and II (OR 2.01, CI 1.46-2.79) compared to level V), and in individuals with decreased range of motion of the ankle (dorsiflexion 1-10 degrees (OR 1.43, CI 1.13-1.83) and ≤ 0 degrees (OR 1.46, CI 1.10-1.93) compared to ≥ 20 degrees). With increasing age the OR of pain increased (OR 1.02, CI 1.01-1.03) as well as the reported pain intensity (p < 0.001). CONCLUSIONS: Pain in the foot and lower leg appears to be a significant problem in individuals with CP, particularly in those who walk. As with pain in general in this population, both pain intensity and frequency increase with age. The odds of pain in the foot and lower leg were increased in individuals with limited dorsiflexion of the ankle. Given the cross-sectional design causality cannot be inferred and it is unknown if pain causes decreased range of motion of the ankle or if decreased range of motion causes pain. Further research is needed on causal pathways and importantly on prevention.

Treatment of Hip Displacement in Children With Cerebral Palsy: A 5-year Comparison of Proximal Femoral Osteotomy and Combined Femoral-Pelvic Osteotomy in 163 Children.

BACKGROUND: This study compared the 5-year outcomes of isolated proximal femoral varus osteotomy (FO) and combined proximal femoral varus and pelvic osteotomy (FPO) for the treatment of hip displacement in children with cerebral palsy (CP) in Sweden, focusing on the number of reoperations and residual hip displacement. METHODS: The study included 163 children with a 5-year follow-up after FO or FPO in the national Swedish CP surveillance program, CPUP. Descriptive statistics and univariate and multivariate Cox regression analyses were used to identify whether the age at surgery, sex, Gross Motor Function Classification System level, CP dominant symptom, hip migration percentage (MP), type of surgery (unilateral/bilateral), and history of soft tissue hip surgery were related to the 5-year outcomes after surgery. Failure after hip surgery was defined as a skeletal reoperation involving the hip and/or MP >50%. RESULTS: During the period 2001 to 2017, 163 children (65 girls) underwent 246 femoral and/or pelvic osteotomies (154 FO, 47 bilaterally; 92 FPO, 16 bilaterally) and had a 5-year follow-up; 95 and 74 children had ≥1 FO or FPO as the primary skeletal surgery, respectively. The mean preoperative MP (51%±18% for FO and 59%±17% for FPO, P=0.001) and age at surgery (6.2±2.5 years for FO and 7.3±2.8 years for FPO, P=0.014) differed between procedures. At the 5-year follow-up, 5 hips (5%) had reoperations and 5 hips (5%) had radiological failure among the 92 FPOs, and 33 (21%) had reoperations and 14 (9%) radiological failure among the 154 FOs. The difference in outcome failure rate was significant (P<0.001). Multivariate Cox regression analysis showed a lower risk for failure with FPO [hazard ratio (HR)=0.32, 95% CI: 0.15-0.68] compared with FO. A higher preoperative MP increased the risk for outcome failure (HR=1.21, 95% CI: 1.15-1.36 for each 5% increment). CONCLUSIONS: FPO had a higher mean preoperative MP but a lower 5-year outcome failure rate compared with FO. A higher preoperative MP was associated with an increased risk of failure. LEVEL OF EVIDENCE: Level II-prospective comparative study.

[Significant medical improvements with CPUP - a combined follow-up program and national quality registry for cerebral palsy]. / CPUP ­ från reaktiv till preventiv behandling av cerebral pares.

CPUP is a combined follow-up program and national quality registry for cerebral palsy (CP). Since its inception in southern Sweden in 1994, CPUP has expanded geographically to cover all of Sweden, and similar programs are used in several northern European countries. Over 95% of all children with CP in Sweden, and a growing proportion of adults, are followed according to CPUP. The content of CPUP has been developed to involve most professions working with CP. CPUP has led to significant medical improvements. As an example, the percentage of individuals developing hip dislocation has decreased from 10% to 0.5%. The program's strengths include its interdisciplinary collaboration, user involvement, and the ability to inform and improve the quality of care systematically. Nevertheless, challenges include the need for ongoing funding and support. CPUP's success exemplifies how national quality registers can integrate into healthcare, enabling a shift from reactive to proactive care.

An Integrated Approach for Real-Time Monitoring of Knee Dynamics with IMUs and Multichannel EMG.

Measuring human joint dynamics is crucial for understanding how our bodies move and function, providing valuable insights into biomechanics and motor control. Cerebral palsy (CP) is a neurological disorder affecting motor control and posture, leading to diverse gait abnormalities, including altered knee angles. The accurate measurement and analysis of knee angles in individuals with CP are crucial for understanding their gait patterns, assessing treatment outcomes, and guiding interventions. This paper presents a novel multimodal approach that combines inertial measurement unit (IMU) sensors and electromyography (EMG) to measure knee angles in individuals with CP during gait and other daily activities. We discuss the performance of this integrated approach, highlighting the accuracy of IMU sensors in capturing knee joint movements when compared with an optical motion-tracking system and the complementary insights offered by EMG in assessing muscle activation patterns. Moreover, we delve into the technical aspects of the developed device. The presented results show that the angle measurement error falls within the reported values of the state-of-the-art IMU-based knee joint angle measurement devices while enabling a high-quality EMG recording over prolonged periods of time. While the device was designed and developed primarily for measuring knee activity in individuals with CP, its usability extends beyond this specific use-case scenario, making it suitable for applications that involve human joint evaluation.

Epidemiology of fractures in children with cerebral palsy: a Swedish population-based registry study.

BACKGROUND: Children with cerebral palsy (CP) form a heterogeneous group and may have risk or protective factors for fractures compared with typically developing children. The fracture sites may also differ from those of children who do not have CP. We analyzed the fracture epidemiology in a total population of children with CP. METHODS: This was a retrospective registry study based on data from the Swedish Cerebral Palsy Follow-Up Program (CPUP) and the Swedish National Patient Register. All children in the CPUP born in 2000-2015 were included. The Gross Motor Function Classification System (GMFCS) level, reported fractures, fracture site, and epilepsy diagnosis were recorded up to 2018. Hazards and hazard ratios were calculated for first-time fractures. RESULTS: Of the 3,902 participants, 368 (9.4%) had at least one reported fracture. The cumulative risk of sustaining a fracture before age 16 years was 38.3% (95% confidence interval 33.9-42.4). The hazard for fracture was 7 times higher in children with epilepsy. The overall fracture incidence was not statistically significantly related to sex or GMFCS level. Fractures in the upper extremities were most prevalent in children with a lower GMFCS level, and femoral fractures were most prevalent in children at GMFCS level V. Most fractures occurred in early childhood and after 8 years of age. CONCLUSIONS: Children with CP were at similar risk of sustaining fractures as typically developing children, but the risk was higher in children with comorbid epilepsy. Fractures occurred in children at GMFCS levels I-III at sites similar to those for typically developing children; fractures in the upper extremities were the most frequent. Children at GMFCS levels IV or V and those with epilepsy were more likely to have a fracture in the lower extremities, and the femur was the most frequent site.

Postoperative growth rate affects time to growth arrest after percutaneous physiodesis: A radiostereometric analysis.

Purpose: The aim of this study was to determine the time at which physeal arrest is achieved after percutaneous physiodesis, and whether immediate postoperative growth rate affects the time to reach physeal arrest. Methods: Radiostereometric analysis, with implantation of tantalum balls as radiographic markers on each side of the physes, was used to measure residual longitudinal growth in 21 children (10 boys and 11 girls) after percutaneous physiodesis for leg length discrepancy or extreme tall stature. In total, 25 femoral and 20 tibial physes were operated on. Median age at surgery was 13.9 years (range = 11.4-16.1). Radiostereometric analysis was performed postoperatively and after 3, 6, 9, 12, 26, and 52 weeks. Longitudinal growth rate <50 µm per week was defined as physeal arrest. Descriptive statistics were used for evaluation. Results: Physeal arrest was obtained in 19 of the 21 children (40 physes) within 12 weeks postoperatively. One child was reoperated on in three out of four physes because of continued growth, and in one child, delayed physeal arrest was present at 26 weeks postoperatively. Time to physeal arrest was longer in physes with a higher immediate postoperative growth rate. Conclusion: Postoperative follow-up with radiostereometric analysis at 12 and 15 weeks can determine whether physeal arrest has been achieved. The immediate postoperative growth rate after physiodesis seems to affect the time to physeal arrest. This implies that the risk for complications is greater for children during an accelerated growth period, for example, in boys, younger children and in distal femoral physes. Level of evidence: level III.

The foot drawing method: reliability of measuring foot length and outward rotation in children with clubfoot.

BACKGROUND: The Ponseti method is the gold standard for clubfoot treatment. However, relapse and residual gait deviations are common, and follow-up until 7 years of age is recommended. We evaluated the reliability of the foot drawing method, a new instrument for the follow-up of clubfoot. The method uses drawings of the foot in the neutral position and external rotation to measure foot length and outward rotation. METHODS: Nineteen children aged 2.5-7 years who were treated with the Ponseti method for congenital clubfoot were included. Two raters made the drawings twice (D1 and D2). Each rater measured foot length, foot rotation, and foot-tibial rotation independently (D1). Later, the raters repeated the measurements (D2). Interrater reliability was assessed using the D1 from each rater. Intrarater reliability was assessed using the measurements from each rater's D1 and D2. Bland-Altman plots were used to visualize the limits of agreement (LoA). The mean, 95% confidence interval, and one standard deviation of the differences in all measurements were calculated. RESULTS: The mean differences between and within raters were: foot length < 1 mm, foot rotation < 1°, and foot-tibia rotation < 2°, which indicated no systematic differences. The LoA for foot length were: 4.5 mm and 5.9 mm between raters for D1, - 4.8 mm and 5.9 mm for rater 1 (D1-D2), and - 5.1 mm and 5 mm for rater 2 (D1-D2). The LoA for foot rotation: were - 12° and 10.6° between raters (D1), - 8.4° and 6.6° for rater 1 (D1-D2), and - 14° and 14.1° for rater 2 (D1-D2). The LoA for foot-tibia rotation were: - 17.8° and 14.3° between raters (D1), - 12° and 12.2° for rater 1 (D1-D2), and - 12.7° and 13.6° for rater 2 (D1- D2). CONCLUSIONS: The absence of systematic differences between and within raters, and LoA observed indicate that the foot drawing method is applicable in clinical practice and research. However, the results of the foot and foot-tibia rotation analyses imply that caution is needed when interpreting changes in foot rotation in feet with higher degrees of rotation.

Prevalence and treatment of hip displacement in children with cerebral palsy in Finland.

Purpose: The aim was to study the prevalence of hip displacements, dislocations, and the hip surgeries performed in a Finnish cohort of children with cerebral palsy not followed up in a hip surveillance program and to compare these with previous studies performed in Northern European countries before and after the implementation of hip surveillance programs. Methods: A cross-sectional study. A cohort including 480 children with cerebral palsy, born during the period 2000-2018, not enrolled in a hip surveillance program. Migration percentages were recorded from hip radiographs, age at first hip surgery and type of surgery was extracted from medical records. In a separate analysis, the inclusion criteria were adapted to fit two studies analyzing hip dislocation and hip surgery in Sweden, Norway, and Scotland before and after the implementation of a hip surveillance program. Chi-square tests were used to assess differences in proportions between the groups. Results: In total, 286 children (60%) have had at least one hip radiograph. Of these, 10 (3.5%) developed hip dislocation, which is more than in children of countries with hip surveillance programs (Sweden 0.7%, Scotland 1.3%, p < 0.001). Initial surgery to prevent hip dislocation was performed at an older age (p < 0.001). Conclusion: Children with cerebral palsy in Finland not participating in a surveillance hip program were more likely to undergo hip surgery at an older age and to develop hip displacements and dislocations. The results support the effectiveness of surveillance programs to prevent hip dislocation in children with cerebral palsy. Level of evidence: III.

Orthopedic surgical procedures in 3,305 children and young adults with cerebral palsy: a register-based cohort study.

BACKGROUND AND PURPOSE: Few reports have described the panorama of orthopedic surgeries that children with cerebral palsy (CP) undergo. We analyzed the risk of a first surgery, and describe the frequency of orthopedic surgeries in terms of age, sex, anatomical location, and Gross Motor Function Classification System (GMFCS) level in children and young adults with CP. PATIENTS AND METHODS: This was a register-based cohort study of 3,305 individuals followed until 2-25 years of age. We used data from 2 national Swedish registers: the CPUP CP surveillance program and the Swedish National Patient Register. Kaplan-Meier survival curves were calculated to describe the risk of undergoing a first orthopedic surgery, related to age. RESULTS: We included data for 3,311 orthopedic operations in 1,717 surgical sessions. The percentage of children operated on before age 15 years increased from 22% (95% CI 19-26) for GMFCS level I to 70% (CI 64-75) for level V. Ankle and foot surgery was predominant as first surgery for GMFCS I-II, and hip and femur surgery for GMFCS IV-V. Spinal surgery occurred almost exclusively for GMFCS IV-V. Descriptive data showed repeated surgical sessions to be frequent for higher GMFCS levels. INTERPRETATION: The risk of having a first orthopedic surgical treatment increased with increasing GMFCS level and was initiated at younger age in children with higher GMFCS level.

The CPUP Hip Score predicts displacement of the hip in children with cerebral palsy.

AIMS: The Uppföljningsprogram för cerebral pares (CPUP) Hip Score distinguishes between children with cerebral palsy (CP) at different levels of risk for displacement of the hip. The score was constructed using data from Swedish children with CP, but has not been confirmed in any other population. The aim of this study was to determine the calibration and discriminatory accuracy of this score in children with CP in Scotland. METHODS: This was a total population-based study of children registered with the Cerebral Palsy Integrated Pathway Scotland. Displacement of the hip was defined as a migration percentage (MP) of > 40%. Inclusion criteria were children in Gross Motor Function Classification System (GMFCS) levels III to V. The calibration slope was estimated and Kaplan-Meier curves produced for five strata of CPUP scores to compare the observed with the predicted risk of displacement of the hip at five years. For discriminatory accuracy, the time-dependent area under the receiver operating characteristic curve (AUC) was estimated. In order to analyze differences in the performance of the score between cohorts, score weights, and subsequently the AUC, were re-estimated using the variables of the original score: the child's age at the first examination, GMFCS level, head shaft angle, and MP of the worst hip in a logistic regression with imputation of outcomes for those with incomplete follow-up. RESULTS: The discriminatory accuracy of the score in the new population of 367 children was high (AUC 0.78 (95% confidence interval (CI) 0.71 to 0.86)). The calibration of the score was insufficient (slope 0.48 (95% CI 0.31 to 0.65)), and the absolute risks of displacement of the hip in this population were overestimated. The AUC increased with re-estimated weights (0.85 (95% CI 0.79 to 0.91)). CONCLUSION: The CPUP Hip Score had a high ability to discriminate between children at different levels of risk for displacement of the hip. The score overestimated the absolute risks of displacement in this population, which may have resulted from differences in the way children were initially registered in the two programmes. The results are promising, but the score weights may need re-estimation before its clinical application in Scotland. Cite this article: Bone Joint J 2022;104-B(5):640-644.

Development of hip displacement in cerebral palsy: a longitudinal register study of 1,045 children.

Background and purpose - Hip surveillance in children with cerebral palsy (CP) includes repeated radiographic hip examinations and measurements of the hip migration percentage (MP) to identify hips in need of surgery early, to prevent dislocation with the fewest number of radiographic examinations possible. We analyzed the early development of the MP in hips operated on to prevent hip dislocation and hips stabilized without surgery Patients and methods - From the Swedish Surveillance Programme for CP, 5,899 radiographic measurements from 1,045 children with a Gross Motor Function Classification System level III-V born in 1996-2011 were analyzed. For children operated on to prevent hip dislocation, measurements up to the most recent preoperative radiograph were included. The hip with highest MP was analyzed for each child. A mixed-effects model was used to estimate the development of the MP at each age for each child and the population mean. Results - In the 702 children who did not undergo preventive surgery, the mean MP increased with decreasing velocity up to age 6 years. Here it reached 24% (95% confidence interval [CI] 24-25), with a velocity of 0.3%/year (CI 0.0-0.5), remaining approximately stable up to age 12 years. In the 343 children who underwent preventive surgery (219 adductor-psoas lengthening, 124 varus derotation osteotomy of proximal femur), the mean MP increased with an increasing velocity from a mean of 30% (CI 27-32) 3 years before the operation. Interpretation - An increasing rate of hip displacement in hips with an MP > 24% indicates the need for preventive surgery. Hips stabilized without preventive surgery had a decreasing displacement rate and were usually stabilized with an MP < 30% at age 6 years.

Hip development after surgery to prevent hip dislocation in cerebral palsy: a longitudinal register study of 252 children.

Background and purpose - Operative treatment of hip displacement in cerebral palsy (CP) includes adductor-psoas lengthening (APL) or varus derotation osteotomy (VDRO) of the proximal femur, sometimes combined with pelvic osteotomy. After both operations, there is a significant risk of relapse and need for reoperation. We used the migration percentage (MP) to compare the development of hip displacement after APL and VDRO. Patients and methods - All reported MP measurements for children treated with APL (n = 158) or VDRO (n = 94) and followed ≥ 3 years were obtained from the Swedish Surveillance Programme for CP. In children treated with bilateral surgery, the hip with the highest preoperative MP was analyzed. A mixed-effects model was used to estimate the development of MP with age for each child and the population mean. Results - The 104 hips that underwent APL without reoperation showed a gradually reduced MP postoperatively. The 54 hips that underwent a 2nd surgery with APL or VDRO because of redisplacement had a higher displacement rate preoperatively and continued displacement postoperatively but at a slower rate. The 94 hips that underwent VDRO showed an instantaneous decrease in MP postoperatively followed by a rate of increasing displacement. The 15 hips that underwent a 2nd VDRO had a higher rate of displacement both pre- and postoperatively. Interpretation - After APL, hip displacement either decreases or continues to increase but at a slower rate. After VDRO, the MP decreases momentarily but then gradually increases. The risk of reoperation is higher in children with a high preoperative displacement velocity and a high preoperative MP.

Range of hip abduction after preventive and reconstructive surgery in cerebral palsy: a longitudinal registry study of 307 children.

Background and purpose - Hip dislocation in cerebral palsy (CP) is caused by altered muscle forces on the joint during typical hip positioning in adduction-flexion-inward rotation. Preventive surgery includes adductor-psoas lengthening (APL) or varus derotation osteotomy (VDRO) of the proximal femur. We assessed the changes in the hip abduction range after these operations. Patients and methods - Data were obtained from the Swedish Surveillance Programme for CP. The range of hip abduction before and up to 18-36 months after surgery was assessed for all children who underwent APL or VDRO. Data for 1 hip per child was assessed. Ordinary linear regression was used. Results - In the 150 children who underwent APL, the mean range of abduction increased from 29° (95% confidence interval [CI] 28-32) preoperatively to 37° (CI 35-39) at 18-36 months. In the 157 children who underwent VDRO, the respective mean values were 30° (CI 29-32) and 29° (CI 28-31). The mean difference in preoperative abduction between sides was greater in children who underwent unilateral (9.4°, CI 7.8-11) than bilateral (5.5°, CI 3.4-7.6) VDRO. At 18-36 months postoperatively, the differences between sides were almost unchanged. Interpretation - The range of hip abduction increased after APL but remained unchanged after VDRO. This may explain the normal development of hip displacement after these operations. Differences in abduction between sides were not substantially affected by whether VDRO was performed uni- or bilaterally.

Treatment of spasticity in children and adolescents with cerebral palsy in Northern Europe: a CP-North registry study.

BACKGROUND: Spasticity is present in more than 80% of the population with cerebral palsy (CP). The aim of this study was to describe and compare the use of three spasticity reducing methods; Botulinum toxin-A therapy (BTX-A), Selective dorsal rhizotomy (SDR) and Intrathecal baclofen therapy (ITB) among children and adolescents with CP in six northern European countries. METHODS: This registry-based study included population-based data in children and adolescents with CP born 2002 to 2017 and recorded in the follow-up programs for CP in Sweden, Norway, Denmark, Iceland and Scotland, and a defined cohort in Finland. RESULTS: A total of 8,817 individuals were included. The proportion of individuals treated with SDR and ITB was significantly different between the countries. SDR treatment ranged from 0% ( Finland and Iceland) to 3.4% (Scotland) and ITB treatment from 2.2% (Sweden) to 3.7% (Denmark and Scotland). BTX-A treatment in the lower extremities reported 2017-2018 ranged from 8.6% in Denmark to 20% in Norway (p < 0.01). Mean age for undergoing SDR ranged from 4.5 years in Norway to 7.3 years in Denmark (p < 0.01). Mean age at ITB surgery ranged from 6.3 years in Norway to 10.1 years in Finland (p < 0.01). Mean age for BTX-A treatment ranged from 7.1 years in Denmark to 10.3 years in Iceland (p < 0.01). Treatment with SDR was most common in Gross Motor Function Classification System (GMFCS) level III, ITB in level V, and BTX-A in level I. The most common muscle treated with BTX-A was the calf muscle, with the highest proportion in GMFCS level I. BTX-A treatment of hamstring and hip muscles was most common in GMFCS levels IV-V in all countries. CONCLUSION: There were statistically significant differences between countries regarding the proportion of children and adolescents with CP treated with the three spasticity reducing methods, mean age for treatment and treatment related to GMFCS level. This is likely due to differences in the availability of these treatment methods and/or differences in preferences of treatment methods among professionals and possibly patients across countries.

Development of foot length in children with congenital clubfoot up to 7 years of age: a prospective follow-up study.

BACKGROUND: Clubfeet are typically shorter than normal feet. This study aimed first to describe the development of foot length in a consecutive series of children with congenital clubfoot and second to relate foot length to development of relapse and motion quality. METHODS: Foot length was measured every 6 months in 72 consecutive children with congenital clubfoot (29 bilateral) aged from 2 to 7 years. The initial treatment was nonsurgical followed by standardized orthotic treatment. Foot length growth rate was calculated every half year. In children with unilateral clubfeet, the difference in foot length between the clubfoot and the contralateral foot was calculated. Motion quality was evaluated by the Clubfoot Assessment Protocol (CAP). Student's t test, the Mann-Whitney U test and Spearman's correlation were used for group comparisons. Bonferroni correction was used when multiple comparisons were performed. RESULTS: Clubfeet were smaller (P < 0.001) than reference feet at all ages but had a similar growth rate up to age 7. Unilateral clubfeet with greater difference in size compared with the contralateral foot at the first measurement, relapsed more frequently (P = 0.016) and correlated with poorer motion quality (r = 0.4; P = 0.011). CONCLUSIONS: As previously reported, clubfeet were smaller than reference feet at all ages. The growth rate, however, was similar between clubfeet and reference feet. Children with unilateral clubfeet and greater foot length difference at 2 years of age had a higher tendency to relapse and poorer motion quality at 7 years of age, indicating that foot length could be used as a prognostic tool.

Point prevalence and motor function of children and adolescents with cerebral palsy in Scandinavia and Scotland: a CP-North study.

AIM: To describe the point prevalence of cerebral palsy (CP) and distribution of gross and fine motor function in individuals registered in a CP-North surveillance programme. METHOD: Aggregate data of individuals with CP aged 6 to 19 years, sex, CP subtype, and gross and fine motor function levels were collected from each programme. Overall and age-specific point prevalence of CP was calculated for each programme using 95% confidence intervals. Logistic regression was used to estimate prevalence and CP subtypes with age as the covariate variable. Pearson χ2 tests were used to compare the distributions of CP subtypes, Gross Motor Function Classification System (GMFCS) levels, and Manual Ability Classification System (MACS) levels by age and between programmes. RESULTS: Among 3 759 138 individuals residing in Scandinavia and Scotland, 8278 had a diagnosis of CP (57-59% were males). The overall point prevalence of CP ranged from 2.13 to 2.32 per 1000 residents. Age-specific prevalence in each programme varied with the exception of Denmark. While the proportions of bilateral spastic CP were similar between programmes, there were variations in all other CP subtypes and in GMFCS and MACS levels. INTERPRETATION: While the results of this study may reflect real differences in CP populations between countries, they may not be clinically relevant. The variations may be attributable to differences in the year when each programme was first established, different data collection methods, and country-specific governmental policies.

Association between pelvic obliquity and scoliosis, hip displacement and asymmetric hip abduction in children with cerebral palsy: a cross-sectional registry study.

BACKGROUND: Pelvic obliquity (PO) is common in individuals with cerebral palsy (CP). The prevalence of PO in a population of children with CP and its associations with scoliosis, hip displacement and asymmetric range of hip abduction were analysed. METHODS: Over a 5-year period all pelvic radiographs from the Swedish surveillance programme for CP and the recorded data for scoliosis and hip abduction in children from southern Sweden at Gross Motor Function Classification System (GMFCS) levels II-V were analysed. PO and hip displacement calculated as migration percentage (MP) were measured on supine pelvic radiographs and compared with presence of scoliosis and side difference in hip abduction. Statistical analyses comprised chi-squared and binominal testing. RESULTS: In total, 337 children were analysed, of whom 79 had a PO of ≥5°. The proportion of children with PO increased from 16% in GMFCS level II to 34% in level V. Scoliosis combined with PO was reported in 38 children, of whom 34 (89%, 95% confidence interval [CI] 80-99%) had the convexity opposite to the high side of the PO. Asymmetric abduction with PO was reported in 45 children, of whom 40 (89%, CI 79-99%) had reduced abduction on the high side of the PO. Asymmetric MP of ≥5% with PO was seen in 62 children, of whom 50 had higher MP on the high side of the PO (81%, CI 71-90%). Children in GMFCS levels II-IV more often had isolated infra-pelvic association with PO (47% versus 19% in GMFCS V, P = 0.025), while combined supra- and infrapelvic association was more common in GMFCS level V (65% versus 30% in GMFCS II-IV, P = 0.004). Isolated infrapelvic or no association was seen in 74% of children ≤10 years of age while 76% of children ≥11 years old had suprapelvic or combined supra- and infrapelvic association with PO (P < 0.001). CONCLUSIONS: There was a strong association between the high side of the PO and the side of scoliosis, highest MP, and lowest range of abduction when PO was measured in supine position. PO was more often associated with infrapelvic factors. PO was seen in young children indicating the need for early awareness of this complication.

Self-versus Proxy-Reported Pain in Children with Cerebral Palsy: A Population-Based Registry Study of 3783 Children.

Objective: To assess how the prevalence of pain in a population-based sample of children and adolescents with cerebral palsy (CP) differ based on self- or proxy reporting. Methods: This cross-sectional registry study included 3783 children (58% boys), 1 to 18 years old, enrolled in the Swedish follow-up program for CP. Logistic regression was used to regress source of reporting (self or proxy) on the presence of general pain adjusted for age, sex, Gross Motor Function Classification System (GMFCS), and Communication Function Classification System (CFCS) levels, including marginal effects between source of reporting and adjusted covariates. Results: The pain item was self-reported in 45%, proxy-reported in 51%, and information was missing in 3%. Pain was reported in 44% of those who self-reported and in 41% of those who proxy-reported (P = .04). The logistic regression showed that the average marginal effects of proxy versus self-reported pain were lower among children at GMFCS level IV (-0.14, 95% CI -0.17 to -0.03) and CFCS level I (-0.09, CI -0.16 to -0.01) and higher at CFCS level III (0.11, CI 0.00-0.22). There were no statistically significant differences in average marginal effects related to age, sex, or the other GMFCS and CFCS levels between proxy and self-reporting. Conclusions: Pain was more often reported by those who self-reported. However, after adjusting for age, sex, CFCS level, and GMFCS level, the proportion of reported pain was almost equal between self and proxy-reporting. Assuming that the self- and proxy-reported groups were not significantly different on relevant factors not controlled for the results indicate that presence of pain is equally reported by children and parents.