Demographic and modifiable factors associated with knee contracture in children with cerebral palsy

Biomechanical testing of ex vivo porcine tendons following high intensity focused ultrasound thermal ablation

INTRODUCTION

Magnetic resonance-guided focused ultrasound (MRgFUS) has been demonstrated to be able to thermally ablate tendons with the aim to non-invasively disrupt tendon contractures in the clinical setting. However, the biomechanical changes of tendons permitting this disrupting is poorly understood. We aim to obtain a dose-dependent biomechanical response of tendons following magnetic resonance-guided focused ultrasound (MRgFUS) thermal ablation.

METHODS

Ex vivo porcine tendons (n = 72) were embedded in an agar phantom and randomly assigned to 12 groups based on MRgFUS treatment. The treatment time was 10, 20, or 30s, and the applied acoustic power was 25, 50, 75, or 100W. Following each MRgFUS treatment, tendons underwent biomechanical tensile testing on an Instron machine, which calculated stress-strain curves during tendon elongation. Rupture rate, maximum treatment temperature, Young's modulus and ultimate strength were analyzed for each treatment energy.

RESULTS

The study revealed a dose-dependent response, with tendons rupturing in over 50% of cases when energy delivery exceeded 1000J and 100% disruption at energy levels beyond 2000J. The achieved temperatures during MRgFUS were directly proportional to energy delivery. The highest recorded temperature was 56.8°C ± 9.34 (3000J), while the lowest recorded temperate was 18.6°C ± 0.6 (control). The Young's modulus was highest in the control group (47.3 MPa ± 6.5) and lowest in the 3000J group (13.2 MPa ± 5.9). There was no statistically significant difference in ultimate strength between treatment groups.

CONCLUSION

This study establishes crucial thresholds for reliable and repeatable disruption of tendons, laying the groundwork for future in vivo optimization. The findings prompt further exploration of MRgFUS as a non-invasive modality for tendon disruption, offering hope for improved outcomes in patients with musculotendinous contractures.

Knee and ankle range of motion and spasticity from childhood into adulthood: a longitudinal cohort study of 3,223 individuals with cerebral palsy

BACKGROUND AND PURPOSE

Reduced range of motion (ROM) and spasticity are common secondary findings in cerebral palsy (CP) affecting gait, positioning, and everyday functioning. These impairments can change over time and lead to various needs for intervention. The aim of this study was to analyze the development path of the changes in hamstring length, knee extension, ankle dorsiflexion, and spasticity in hamstrings and gastrosoleus from childhood into adulthood in individuals with CP at the Gross Motor Function Classification System (GMFCS) levels I-V.

METHODS

A longitudinal cohort study was undertaken of 61,800 measurements in 3,223 individuals with CP, born 1990-2017 and followed for an average of 8.7 years (range 0-26). The age at examination varied between 0 and 30 years. The GMFCS levels I-V, goniometric measurements, and the modified Ashworth scale (MAS) were used for repeated assessments of motor function, ROM, and spasticity.

RESULTS

Throughout the follow-up period, knee extension and hamstring length exhibited a consistent decline across all individuals, with more pronounced decreases evident in those classified at GMFCS levels III-V. Ankle dorsiflexion demonstrated a gradual reduction from 15° to 5° (GMFCS I-IV) or 10° (GMFCS V). Spasticity levels in the hamstrings and gastrosoleus peaked between ages 5 and 7, showing a propensity to increase with higher GMFCS levels.

CONCLUSION

Passive ROM continues to decrease to 30 years of age, most pronouncedly for knee extension. Conversely, spasticity reached its peak at a younger age, with a more notable occurrence observed in the gastrosoleus compared with the hamstrings. Less than 50% of individuals had spasticity corresponding to MAS 2-4 at any age.

Anterior Distal Femoral Hemiepiphysiodesis Does Not Change Pelvic Tilt in Children With Cerebral Palsy

BACKGROUND

Anterior distal femoral hemiepiphysiodesis (ADFH) is a surgical treatment choice to correct flexed knee gait and fixed knee flexion deformities in children with cerebral palsy who are skeletally immature. Increased anterior pelvic tilt has been reported after surgeries that correct knee flexion deformities, including hamstring lengthening (HSL) and distal femoral extension osteotomies, but anterior pelvic tilt has not been studied after ADFH. We hypothesized that anterior pelvic tilt would increase after ADFH, especially when combined with HSL, and it would correlate with the change in minimum knee flexion in stance and dynamic hamstring lengths.

METHODS

Thirty-four eligible participants (age: 13.0, SD: 2.0) were included. Change in mean pelvic tilt across the gait cycle was compared as a function of clinical and gait parameters using linear mixed models. The relationship of change in pelvic tilt to change in other variables was examined using Pearson correlation.

RESULTS

Overall, anterior pelvic tilt increased significantly after ADFH by 4.4 degrees ( P = 0.02). Further, the analysis revealed anterior pelvic tilt only increased significantly in the group that had concurrent HSL (11.1 degrees, P < 0.001). Overall, minimum knee flexion significantly decreased (increase in knee extension) in stance (-19.1 degrees, P < 0.001) and there was an increase in maximum normalized dynamic hamstring lengths (0.03, P < 0.001). The anterior pelvic tilt increased significantly in Gross Motor Function Classification System levels III to IV (5.9 degrees, P = 0.02) but did not change significantly in Gross Motor Function Classification System I to II (2.5 degrees, P = 0.37). Change in pelvic tilt was correlated with change in maximum dynamic hamstring lengths ( r = 0.87, P < 0.0001) and change in minimum knee flexion in stance ( r = -0.71, P < 0.0001).

CONCLUSIONS

Anterior distal hemiepiphysiodesis without concurrent HSL for flexion knee deformities does not result in increased anterior pelvic tilt. Surgeons should consider anterior distal hemiepiphysiodesis in patients with cerebral palsy and flexed knee gait, who preoperatively have long dynamically modeled hamstrings, are skeletally immature, and when maintenance of pelvic tilt is desired.

LEVEL OF EVIDENCE

Level III-retrospective comparative study.

Range of Motion Limitations in Middle-aged Adults With Cerebral Palsy

Objective

To describe limitations in range of motion (ROM) in middle-aged adults with cerebral palsy (CP), and identify associations with CP subtype, gross motor function, sex and age.

Design

Population-based cohort study.

Setting

Local and regional referral centers.

Participants

Inclusion criteria: diagnosis of CP, born 1959 to 1978 and living in the county of Västra Götaland, Sweden. In the population-based register of CP in Western Sweden, 417 subjects were identified and 139 volunteered to participate. Adults with CP, born elsewhere, who had moved into the area were invited through patient organizations and habilitation units, and eleven chose to participate. In total 150 participants, age 37-58 years (mean 48) 65 women (43%) (N=150). All CP subtypes and Gross Motor Function Classification (GMFCS) levels were represented.

Interventions

Not applicable.

Main Outcome Measures

Passive ROM was measured in the upper and lower extremity and was classified into 4 levels (inspired by The Spinal Alignment and Range of Motion Measure and adapted from the values of the American Academy of Orthopedic Surgeons); good=1, vs mild=2, moderate=3 or severe=4 limitation. The results were summarized to obtain a total score of the participants' ROM limitations.

Results

Moderate to severe limitations were present in 98 % of the participants. There was a correlation to GMFCS level in both the upper and lower extremity (P<.001), but no correlation with age. Upper extremity limitations were most common in dyskinetic CP, lower extremity limitations were most common in dyskinetic CP and bilateral spastic CP. Men had more limitations in the lower extremity (P=.001). The most common limitation in the lower extremity was hamstrings tightness (82%) and hip abduction (80%), and in the upper extremity, limited shoulder abduction (57%).

Conclusions

Limited ROM is common in adults with CP, most pronounced in shoulders, hip joints and hamstrings muscles, with no differences related to age in this age-span.

Prevalence of knee contractures is high in children with cerebral palsy in Denmark

INTRODUCTION

Cerebral palsy (CP) is a neurological disease occurring in children at early gestation, often resulting in pronounced functional limitations. A Swedish cross-sectional study (Cloodt, et al., 2018) discovered that 22% of children with CP had a knee contracture, which was associated with higher levels of Gross Motor Function Classification System (GMFCS), higher age, and higher levels of spasticity measured by the Modified Ashworth Scale (MAS). The current study investigated these associations in a Danish population.

METHODS

This is a cross-sectional study including 1,163 children with CP aged 0-15 years, registered in the Danish National Cerebral Palsy Registry between 2017 and 2019. Prevalence of knee contracture was estimated, and logistic regression analysis was applied with results presented as odds ratio (OR) with 95% confidence intervals (CI).

RESULTS

A total of 511 children with CP had knee contracture resulting in a prevalence of 44%. Age groups 4-6 years (OR: 1.73, CI: 1.19; 2.52), 7-9 years (OR: 1.85, CI: 1.29; 2.66) and 10-12 years (OR: 2.12, CI: 1.39; 3.24) were significantly associated with a higher prevalence of knee contractures compared to age group 0-3 years. Knee contractures were significantly more frequent at GMFCS levels IV (OR: 1.9, CI: 1.21; 2.97) and V (OR: 3.62, CI: 2.36; 5.55) compared to level I. Knee contractures were not associated with higher levels of MAS.

CONCLUSIONS

Knee contractures are highly prevalent and significantly associated with high levels of GMFCS and increased age until 12 years, but not with high levels of spasticity in children with CP in Denmark.

Relationship between scoliosis, windswept hips and contractures with pain and asymmetries in sitting and supine in 2450 children with cerebral palsy

PURPOSE

This cross-sectional study of 2450 children with cerebral palsy aimed to analyse the prevalence and association of scoliosis, windswept hips, hip and knee contractures.

METHODS

Logistic regression was used to estimate associations with pain, postural asymmetries, and ability to change position for children at Gross Motor Function Classification System (GMFCS) levels I-V, aged 0-18 years.

RESULTS

Most children with a deformity or contracture had postural asymmetries in both sitting and supine positions; 10.5% had scoliosis, 8.7% windswept hips, 6.6% hip flexion and 19.2% knee contractures. Severe postural asymmetries increased the likelihood for scoliosis 9 times, for windswept hips 6 to 9 times, and for hip and knee flexion contractures 7 and 12 times respectively, adjusted for age, sex and GMFCS level. Hip flexion contractures and windswept hips increased the likelihood for pain by 1.5-1.6 times.

CONCLUSION

The likelihood of having scoliosis, windswept hips and flexion contractures in the hips and knees increased if the child had postural asymmetries, and for increased age and higher GMFCS levels. Efforts should focus on preventing postural asymmetries from occurring or progressing, and on increasing the child's ability to change position. Reducing postural asymmetries may also reduce the likelihood of pain.Implications for RehabilitationThe risk of having scoliosis, windswept hip deformity and flexion contractures in the hips and knees increased if the child had postural asymmetries in sitting or lying.Efforts should focus on preventing or reducing postural asymmetries, and on increasing the child's ability to change position.Reducing postural asymmetries may also reduce the risk of pain.

Sequence of flexion contracture development in the lower limb: a longitudinal analysis of 1,071 children with cerebral palsy

Background

To prevent severe contractures and their impact on adjacent joints in children with cerebral palsy (CP), it is crucial to treat the reduced range of motion early and to understand the order by which contractures appear. The aim of this study was to determine how a hip–knee or ankle contracture are associated with the time to and sequence of contracture development in adjacent joints.

Methods

This was a longitudinal cohort study of 1,071 children (636 boys, 435 girls) with CP born 1990 to 2018 who were registered before 5 years of age in the Swedish surveillance program for CP and had a hip, knee or ankle flexion contracture of ≥ 10°. The results were based on 1,636 legs followed for an average of 4.6 years (range 0–17 years). The Cox proportional-hazards model adjusted for Gross Motor Function Classification System (GMFCS) levels I–V was used to compare the percentage of legs with and without more than one contracture.

Results

A second contracture developed in 44% of the legs. The frequency of multiple contractures increased with higher GMFCS level. Children with a primary hip or foot contracture were more likely to develop a second knee contracture. Children with a primary knee contracture developed either a hip or ankle contracture as a second contracture.

Conclusions

Multiple contractures were associated with higher GMFCS level. Lower limb contractures appeared in specific patterns where the location of the primary contracture and GMFCS level were associated with contracture development in adjacent joints.

Knee flexion contracture impacts functional mobility in children with cerebral palsy with various degree of involvement: a cross-sectional register study of 2,838 individuals

Background and purpose - The impact of knee flexion contracture (KFC) on function in cerebral palsy (CP) is not clear. We studied KFC, functional mobility, and their association in children with CP.Subjects and methods - From the Swedish national CP register, 2,838 children were defined into 3 groups: no (≤ 4°), mild (5-14°), and severe (≥ 15°) KFC on physical examination. The Functional Mobility Scale (FMS) levels were categorized: using wheelchair (level 1), using assistive devices (level 2-4), walking independently (level 5-6). Standing and transfer ability and Gross Motor Function Classification (GMFCS) were assessed.Results - Of the 2,838 children, 73% had no, 14% mild, and 13% severe KFC. KFC increased from 7% at GMFCS level I to 71% at level V. FMS assessment (n = 2,838) revealed around 2/3 were walking independently and 1/3 used a wheelchair. With mild KFC (no KFC as reference), the odds ratio for FMS level 1 versus FMS level 5-6 at distances of 5, 50, and 500 meters, was 9, 9, and 8 respectively. Correspondingly, with severe KFC, the odds ratio was 170, 260, and 217. In no, mild, and severe KFC 14%, 47%, and 77% could stand with support and 11%, 25%, and 33% could transfer with support.Interpretation - Knee flexion contracture is common in children with CP and the severity of KFC impacts function. The proportion of children with KFC rose with increased GMFCS level, reduced functional mobility, and decreased standing and transfer ability. Therefore, early identification and adequate treatment of progressive KFC is important.

Ankle contractures are frequent among children with cerebral palsy and associated with lower gross motor function and degree of spasticity

AIM

To estimate yearly prevalence of ankle contractures among children with cerebral palsy (CP). Moreover, to investigate whether age, gross motor function or spasticity are associated with ankle contracture.

METHODS

We examined yearly prevalence of ankle contractures among 933 children based on data from a national clinical quality database from 2012 to 2019. We used the Gross Motor Function Classification System (GMFCS) and the Modified Ashworth Scale (MAS) to assess gross motor function and spasticity in the plantar flexors. Ankle contracture was defined as dorsiflexion with an extended knee equal to or below 0 degrees. Associations between age, GMFCS, spasticity and ankle contractures were analysed using multivariable regression and presented as odds ratios (OR) with 95% confidence intervals (95%CI).

RESULTS

The prevalence of ankle contracture was 32% and did not change with calendar year. GMFCS IV-V compared to I-III (40.6% vs. 28.9%, OR = 1.5 (95%CI: 1.07-2.11) and MAS 2-4 compared to 0 (44.6% vs. 24.4%, OR = 2.5 (95%CI: 1.59-3.91) were associated with a higher prevalence of ankle contracture. Age was not associated with ankle contracture.

CONCLUSION

Ankle contractures are frequent among children with CP. Lower gross motor function and severe spasticity were associated with ankle contracture.

Modular reorganization of gait in chronic but not in artificial knee joint constraint

It is currently unknown if modular reorganization does occur if not the central nervous system, but the musculoskeletal system is affected. The aims of this study were to investigate 1) the effects of an artificial knee joint constraint on the modular organization of gait in healthy subjects; and 2) the differences in modular organization between healthy subjects with an artificial knee joint constraint and people with a similar but chronic knee joint constraint. Eleven healthy subjects and eight people with a chronic knee joint constraint walked overground at 1 m/s. The healthy subjects also walked with a constraint limiting knee joint movement to 20°. The total variance accounted (tVAF) for one to four synergies and modular organization were assessed using surface electromyography from 11 leg muscles. The distribution of number of synergies were not significantly different between groups. The tVAF and the motor modules were not significantly affected by the artificial knee constraint. A higher tVAF for one and two synergies, as well as merging of motor modules were observed in the chronic knee constraint group. We conclude that in the short-term a knee constraint does not affect the modular organization of gait, but in the long-term a knee constraint results in modular reorganization. These results indicate that merging of motor modules may also occur when changes in the mechanics of the musculoskeletal system is the primary cause of the motor impairment.NEW & NOTEWORTHY It is currently unknown if modular reorganization does occur if not the central nervous system, but the musculoskeletal system is affected. This study showed that in the short-term a knee constraint does not affect the modular organization of gait, but in the long-term a knee constraint results in modular reorganization. These results indicate that modular reorganization may also occur when changes in the mechanics of the musculoskeletal system is the primary cause of the motor impairment.

The influence of preoperative knee flexion contracture severity on short-term outcome of orthopedic surgery in ambulatory children with bilateral cerebral palsy

BACKGROUND

Indications and cutoff value of deformities to determine surgical procedures for flexed knee gait are not clear. The aim was to determine the influence of none or mild, and moderate preoperative knee flexion contracture on the improvement of gait after orthopedic surgery in children with bilateral cerebral palsy (CP).

METHODS

Inclusion criteria; bilateral CP, Gross Motor Function Classification System level I-III, and pre- and post operative-gait analysis. The 132 individuals identified were categorized into 2 groups based on the severity of knee flexion contracture (group 1: none or less than 11°; group 2: greater than or equal to 11°), and then matched according to the exact same soft tissue and/or bony orthopedic surgical procedures performed. The indication for surgery was to prevent progressive development of knee flexion contracture and stance phase flexed knee gait. Pre- and postoperative physical examination and gait analysis data were analyzed retrospectively.

RESULTS

Sixty (30 + 30) children, with mean age 10.6 years in each group, were included. The average follow-up time was 17 months. Gait Deviation Index (GDI) improved in group 1 from mean 66 (SD 19) to 74 (15), p = 0.004, and in group 2 from 60 (13) to 69 (15), p = 0.001. Knee flexion in stance improved in group 1 from 21.4 (16.1) to 12.1 (16.0) degrees, p = 0.002, and in group 2 from 32.2 (14.2) to 17.0 (15.9), p = 0.001. Step length improved in both groups, p = 0.017 and p = 0.008, respectively. Only in group 2 significant improvement was noted in walking speed, p = 0.018 and standing function, Gross Motor Function Measure (GMFM-D), p = 0.001. Knee flexion contracture decreased in group 1 from mean 4.6 (5.3) to 2.1 (8.3) degrees, p = 0.071 and in group 2 from 17.2 (4.9) to 9.6 (9.3), p = 0.001. There was no statistical difference between groups in pre-post improvement of GDI or other variables, except GMFM-D.

CONCLUSIONS

Relative mild to moderate preoperative knee flexion contracture does not influence the short-term improvement of gait after orthopedic surgery in children with bilateral CP.

Contribution of extracellular matrix components to the stiffness of skeletal muscle contractures in patients with cerebral palsy

Purpose: Joint contractures in children with cerebral palsy contain muscle tissue that is mechanically stiffer with higher collagen content than typically developing children. Interestingly, the correlation between collagen content and stiffness is weak. To date, no data are available on collagen types or other extracellular matrix proteins in these muscles, nor any information regarding their function. Thus, our purpose was to measure specific extracellular protein composition in cerebral palsy and typically developing human muscles along with structural aspects of extracellular matrix architecture to determine the extent to which these explain mechanical properties. Materials and Methods: Biopsies were collected from children with cerebral palsy undergoing muscle lengthening procedures and typically developing children undergoing anterior cruciate ligament reconstruction. Tissue was prepared for the determination of collagen types I, III, IV, and VI, proteoglycan, biglycan, decorin, hyaluronic acid/uronic acid and collagen crosslinking. Results: All collagen types increased in cerebral palsy along with pyridinoline crosslinks, total proteoglycan, and uronic acid. In all cases, type I or total collagen and total proteoglycan were positive predictors, while biglycan was a negative predictor of stiffness. Together these parameters accounted for a greater degree of variance within groups than across groups, demonstrating an altered relationship between extracellular matrix and stiffness with cerebral palsy. Further, stereological analysis revealed a significant increase in collagen fibrils organized in cables and an increased volume fraction of fibroblasts in CP muscle. Conclusions: These data demonstrate a novel adaptation of muscle extracellular matrix in children with cerebral palsy that includes alterations in extracellular matrix protein composition and structure related to mechanical function.

Hip contractures were associated with low gross motor function in children with cerebral palsy

AIM

The aim was to identify the prevalence of hip contractures and their association with gross motor function and pain in the lower extremities among Danish children with cerebral palsy (CP).

METHODS

This cross-sectional study was based on data collected during regular clinical examinations in 2018-2019 and registered in the National Danish Clinical Quality Database of children with CP. The study population was 688 children (59% boys) aged five to 12 years across all Gross Motor Function Classification System (GMFCS) levels. Any associations between hip contracture and gross motor function and pain were investigated with logistic regression analysis and presented as odds ratios (OR) with 95% confidence intervals (95% CI).

RESULTS

The prevalence of hip contracture was 22% across all five GMFCS levels, and the incidence varied across the five Danish regions. The odds ratios for hip contracture were significantly higher at GMFCS level IV (OR 1.99, 95% CI 1.10-3.62) and V (OR 5.49, 95% CI 3.33-9.07) compared with level I. Hip contractures were not significantly associated with pain in the lower extremities (OR 1.43, 95% CI 0.95-2.15).

CONCLUSION

Hip contractures were frequent and associated with low gross motor function, but not lower extremity pain, in children with CP.

Knee and foot contracture occur earliest in children with cerebral palsy: a longitudinal analysis of 2,693 children

Background and purpose - Joint contracture is a common problem among children with cerebral palsy (CP). To prevent severe contracture and its effects on adjacent joints, it is crucial to identify children with a reduced range of motion (ROM) early. We examined whether significant hip, knee, or foot contracture occurs earliest in children with CP.Patients and methods - This was a longitudinal study involving 27,230 measurements obtained for 2,693 children (59% boys, 41% girls) with CP born 1990 to 2018 and registered before 5 years of age in the Swedish surveillance program for CP. The analysis was based on 4,751 legs followed up for an average of 5.0 years. Separate Kaplan-Meier (KM) curves were drawn for each ROM to illustrate the proportions of contracture-free legs at a given time during the follow-up. Using a clustered bootstrap method and considering the child as the unit of clustering, 95% pointwise confidence intervals were generated for equally spaced time points every 2.5 years for each KM curve.Results - Contracture developed in 34% of all legs, and the median time to the first contracture was 10 years from the first examination. Contracture was most common in children with a higher Gross Motor Function Classification System (GMFCS) level. The first contracture was a flexion contracture preventing dorsiflexion in children with GMFCS level I or II and preventing knee extension in children with GMFCS level III to V.Interpretation - Early interventions to prevent knee and foot contractures in children with CP should be considered.

Musculoskeletal Pathology in Cerebral Palsy: A Classification System and Reliability Study

This article presents a classification of lower limb musculoskeletal pathology (MSP) for ambulant children with cerebral palsy (CP) to identify key features from infancy to adulthood. The classification aims to improve communication, and to guide referral for interventions, which if timed appropriately, may optimise long-term musculoskeletal health and function. Consensus was achieved by discussion between staff in a Motion Analysis Laboratory (MAL). A four-stage classification system was developed: Stage 1: Hypertonia: Abnormal postures are dynamic. Stage 2: Contracture: Fixed shortening of one or more muscle-tendon units. Stage 3: Bone and joint deformity: Torsional deformities and/or joint instability (e.g., hip displacement or pes valgus), usually accompanied by contractures. Stage 4: Decompensation: Severe pathology where restoration of optimal joint and muscle-tendon function is not possible. Reliability of the classification was tested using the presentation of 16 clinical cases to a group of experienced observers, on two occasions, two weeks apart. Reliability was found to be very good to excellent, with mean Fleiss' kappa ranging from 0.72 to 0.84. Four-stages are proposed to classify lower limb MSP in children with CP. The classification was reliable in a group of clinicians who work together. We emphasise the features of decompensated MSP in the lower limb, which may not always benefit from reconstructive surgery and which can be avoided by timely intervention.

Interrater reliability for unilateral and bilateral tests to measure the popliteal angle in children and youth with cerebral palsy

Background

Short hamstring muscles can cause several problems for children with cerebral palsy. The results of the clinical measurement of hamstring length are often used in decision-making about treatment of children with cerebral palsy. There are different ways of performing this measurement. The aim of this study was to evaluate the interrater reliability of the unilateral and bilateral measurement of the popliteal angle in children and youth with cerebral palsy.

Methods

Two methods for estimating hamstring length using unilateral and bilateral measurements of the popliteal angle were applied in children with cerebral palsy. Both tests were applied bilaterally by two independent examiners on the same day for each child. The intraclass correlation coefficient (ICC) was calculated to evaluate the interrater reliability of both measurements. Seventy young people with cerebral palsy (32 females, 38 males, mean age 10 years 8 months, range 5–22 years) at Gross Motor Function Classification System levels I (n = 17), II (n = 31), III (n = 12) and IV (n = 10) were included.

Results

The interrater reliability was good for both measurements. The ICC values were 0.80 on the right and 0.86 on the left for the unilateral popliteal angle, and 0.82 on the right and 0.83 on the left for the bilateral popliteal angle.

Conclusions

Both unilateral and bilateral measurement of the popliteal angle is a reliable method for estimating hamstring length in children and youth with cerebral palsy.

Stander Use for an Adolescent with Cerebral Palsy at GMFCS Level with Hip and Knee Contractures

Aims: Adolescents with cerebral palsy (CP) report high rates of pain and contractures. Standing may positively affect these outcomes, yet there are no published studies on how to accommodate contractures or when a stander is no longer beneficial. This is the first study that answers the question: Can an adolescent with CP and 40-degree knee and/or hip flexion contractures benefit from a standing program, after being non-weight bearing for many years? Methods: A 16-year-old male with spastic tetraplegic CP, Gross Motor Function Classification System (GMFCS) level V, used a stander with a "knee and hip contracture system." Knee and hip extension, as well as upright inclination, were increased weekly. Knee and hip passive range of motion (PROM) measurements, pain scale, and a parent survey were completed at baseline, 7 and 15 months. Results: After 15 months of stander use, both hips and left knee PROM improved. The subject's activity and participation increased, while pain, suppository use, and time spent on bowel care decreased. Conclusion: An adolescent with 40-degree knee and hip flexion contractures may be positioned well in a stander with a specialized contracture system. PROM, bowel function, pain, activity, and participation may improve for some adolescents at GMFCS level V, through use of a stander.

Development of a risk score for scoliosis in children with cerebral palsy

Background and purpose - Children and young adults with cerebral palsy (CP) have an increased risk of developing scoliosis, with a prevalence ranging from 11% to 29%. Information on risk factors for the emergence and progression of scoliosis is inconclusive. This study aimed to develop a risk score based on 5-year-old children with CP to predict the risk of scoliosis before the age of 16.Patients and methods - This prospective registry study included 654 children with CP in Sweden born in 2000 to 2003 and registered with the Swedish CP follow-up program (CPUP) at the age of 5 years, including all Gross Motor Function Classification System (GMFCS) levels. 92 children developed a scoliosis before the age of 16 years. Univariable and multivariable logistic regressions were used to analyze 8 potential predictors for scoliosis: GMFCS, sex, spastic subtype, epilepsy, hip surgery, migration percentage, and limited hip or knee extension.Results - 4 predictors for scoliosis remained significant after analyses: female sex, GMFCS levels IV and V, epilepsy, and limited knee extension, and a risk score was constructed based on these factors. The predictive ability of the risk score was high, with an area under the receiver operating characteristics curve of 0.87 (95% CI 0.84-0.91).Interpretation - The risk score shows high discriminatory ability for differentiating between individuals at high and low risk for development of scoliosis before the age of 16. It may be useful when considering interventions to prevent or predict severe scoliosis in young children with CP.

Change in popliteal angle and hamstrings spasticity during childhood in ambulant children with spastic bilateral cerebral palsy. A register-based cohort study

BACKGROUND

Muscle contractures are developing during childhood and may cause extensive problems in gait and every day functioning in children with cerebral palsy (CP). The aim of the present study was to evaluate how the popliteal angle (PA) and hamstrings spasticity change during childhood in walking children with spastic bilateral CP.

METHODS

The present study was a longitudinal register-based cohort study including 419 children (1-15 years of age) with spastic bilateral CP, gross motor function classification system (GMFCS) level I, II and III included in the Norwegian CP Follow-up Program (CPOP). From 2006 to 2018 a total of 2193 tests were performed. The children were tested by trained physiotherapists yearly or every second year, depending on GMFCS level and age. The PA and the hamstrings spasticity (Modified Ashworth scale (MAS)) were measured at every time point. Both legs were included in the analysis.

RESULTS

There was an increase in PA with age for all three GMFCS levels with significant differences between the levels from 1 up to 8 years of age. At the age of 10 years there was no significant difference between GMFCS level II and III. At the age of 14 years all three GMFCS levels had a mean PA above 40° and there were no significant differences between the groups. The hamstrings spasticity scores for all the three GMFCS levels were at the lower end of the MAS (mean < 1+), however they were significantly different from each other until 8 years of age. The spasticity increased the first four years in all three GMFCS levels, thereafter the level I and II slightly increased, and level III slightly decreased, until the age of 15 years.

CONCLUSION

The present study showed an increasing PA during childhood. There were significantly different PAs between GMFCS level I, II and III up to 8 years of age. At the age of 14 years all levels showed a PA above 40°. The spasticity increased up to 4 years of age, but all the spasticity scores were at the lower end of the MAS during childhood.

Effect of a Combined Stretching and Strength Training Program on Gait Function in Children with Cerebral Palsy, GMFCS Level I & II: A Randomized Controlled Trial

Background and objectives: Ambulant children with cerebral palsy (CP) often develop impaired gait, and reduced active knee extension is often a part of the problem. This study aimed to evaluate the effect of a combined intervention program including stretching and progressive resistance exercise (PRE) targeting active knee extension on gait function, in children with spastic CP. Materials and methods: Thirty-seven children (21 boys, 16 girls, mean age 10.2 (±2.3) years), classified by Gross Motor Function Classification System I-III, were randomized to an intervention (n = 17) and a comparison group (n = 20). The intervention group received a 16-week combined exercise program (3 sessions per week) including stretching of hamstrings and PRE targeting the lower extremities, followed by a 16-week maintenance program (1 session per week). The comparison group received care as usual. Gait function was evaluated by three-dimensional gait analysis (3DGA); knee, hip and pelvic kinematics in the sagittal plane, step length and speed, Gait Deviation Index (GDI), and Six-Minute Walk test (6MWT) at 0, 16, and 32 weeks. Results: There were no statistically significant differences between the intervention group and the comparison group for any of the gait parameters measured at 16 and 32 weeks. There was a significant increase in gait distance measured by 6MWT within both groups; however, no differences between the groups were found. Conclusion: A 16-week combined stretching and PRE program followed by a 16-week maintenance program did not improve gait function in ambulant children with CP.

Management of Joint Contractures in the Spastic Upper Extremity

Upper extremity contractures in the spastic patient may result from muscle spasticity, secondary muscle contracture, or joint contracture. Knowledge of the underlying cause is critical in planning successful treatment. Initial management consists of physical therapy and splinting. Botulinum toxin can be helpful, as a therapeutic treatment in relieving spasticity and as a diagnostic tool in determining the underlying cause of the contracture. Surgical management options include release or lengthening of the causative muscle/tendon unit and joint capsular release, as required. Postoperative splinting is important to maintain the improved range of motion and protect any associated tendon lengthening or transfer.