Long-term effects of spasticity treatment, including selective dorsal rhizotomy, for individuals with cerebral palsy

Transcutaneous Spinal Stimulation and Short-Burst Interval Treadmill Training in Children With Cerebral Palsy: A Pilot Study

OBJECTIVE

The purpose of this pilot study was to evaluate the effects of transcutaneous spinal cord stimulation (tSCS) and short-burst interval locomotor treadmill training (SBLTT) on spasticity and mobility in children with cerebral palsy (CP).

METHODS

We employed a single-arm design with two interventions: SBLTT only, and tSCS + SBLTT, in four children with CP. Children received 24-sessions each of SBLTT only and tSCS + SBLTT. Spasticity, neuromuscular coordination, and walking function were evaluated before, immediately after, and 8-weeks following each intervention.

RESULTS

Spasticity, measured via the Modified Ashworth Scale (MAS), reduced in four lower-extremity muscles after tSCS + SBLTT (1.40 ± 0.22), more than following SBLTT only (0.43 ± 0.39). One-minute walk test (1-MWT) distance was maintained during both interventions. tSCS + SBLTT led to improvements in peak hip and knee extension (4.9 ± 7.3° and 6.5 ± 7.7°), that drove increases in joint dynamic range of 4.3 ± 2.4° and 3.8 ± 8.7° at the hip and knee, respectively. Children and parents reported reduction in fatigue and improved gait outcomes after tSCS + SBLTT. Improvements in spasticity and walking function were sustained for 8-weeks after tSCS + SBLTT.

CONCLUSION

These preliminary results suggest that tSCS + SBLTT may improve spasticity while simultaneously maintaining neuromuscular coordination and walking function in ambulatory children with CP.

SIGNIFICANCE

This work provides preliminary evidence on the effects of tSCS and the combination of tSCS + SBLTT in children with CP.

Selective dorsal rhizotomy from indication to rehabilitation: a worldwide survey

PURPOSE

Selective dorsal rhizotomy (SDR) is a neurosurgical treatment used worldwide to reduce spasticity. The procedure has undergone many changes since its introduction in the early 1900s, and currently, different centers vary in many aspects of the procedure. We surveyed centers on different continents regarding SDR indications, surgical techniques, and postoperative rehabilitation.

METHODS

Ten centers worldwide with SDR experience participated in an online survey preparing for a pre-conference workshop in 2022. The main topics were patient characteristics, the selection process, surgery, and rehabilitation.

RESULTS

Universal suitable candidates for SDR were patients with bilateral spastic cerebral palsy, Gross Motor Function Classification System levels II or III, ages 5 to 7 years, and adequate strength, motor control, and access to postoperative rehabilitation. Centers differed in additional inclusion and exclusion criteria and the use of diagnostic tools. Both single- and multilevel approaches were used, with electrophysiological monitoring applied in all approaches. Intensive rehabilitation was recommended after surgery, followed by a less intensive program, with variations in duration, therapy frequency, modalities used, and follow-up periods.

CONCLUSION

This survey demonstrated many similarities in several aspects of the SDR procedure in centers performing SDR worldwide, while considerable variability was also seen. The results emphasize the need for standardized reporting of SDR procedures and outcome measures to enable international comparative studies. A Delphi procedure could be a first step to reaching a consensus on outcome measurements, which may lead to a consensus regarding the most suitable candidates, surgical techniques, and rehabilitation programs to improve functional outcomes.

Preoperative gait pattern as predictor of gait changes following selective dorsal rhizotomy

BACKGROUND

Selective dorsal rhizotomy (SDR) can improve gait in children with spastic paresis. However, outcomes vary, and selecting individuals who will benefit from the procedure remains challenging. How pre-SDR gait pattern predicts post-SDR gait has not previously been investigated.

RESEARCH QUESTION

This study aims to compare how different gait patterns change after SDR to gain insight into the potential relevance of gait patterns as a selection criterion for SDR.

METHODS

Kinematic and kinetic data of nineteen children with bilateral spastic paresis due to cerebral palsy or hereditary spastic paraplegia, with 3D gait analysis before and two years after SDR, were extracted from an in-hospital database. A cluster analysis was performed to distinguish different gait patterns based on sagittal hip, knee and ankle angles pre-SDR. Deviations from typical gait per leg (38 legs) pre- and post-SDR were quantified with the Gait Profile Score (GPS), calculated for joint angles, moments, and powers. GPS was compared pre- and post-SDR per gait pattern, and pre-post differences were compared between gait patterns.

RESULTS

Three distinct pre-SDR gait patterns (GPs) were identified using cluster analysis, with GP1 characterized by increased knee flexion (18 legs), GP2 by increased ankle plantarflexion (14 legs), and GP3 by increased knee flexion and increased ankle plantarflexion (6 legs). GPS-kinematics improved significantly for GP1 (-3.1°) and GP3 (-6.6°), but showed no significant change for GP2. GPS-kinematics improved significantly more in GP3 than in GP2. GPS-moments improved equally in all groups (-0.04Nm/kg--0.07Nm/kg). GPS-powers improved significantly more for GP1 and GP2 (0.07W/kg and 0.24W/kg, respectively) than for GP3 where no change occurred.

SIGNIFICANCE

The results suggest that different pre-SDR gait patterns have distinct outcomes post-SDR in children with spastic paresis. Therefore gait patterns could guide selection and expectation management for SDR. Future studies should confirm these results in a larger cohort.

Short-term selective dorsal rhizotomy responders among children with bilateral cerebral palsy

AIM

To identify the short-term effects of selective dorsal rhizotomy (SDR) on gait and clinical impairments in children with bilateral spastic cerebral palsy (CP) and subgroups based on baseline gait patterns.

METHOD

Eighty-nine children with bilateral spastic CP (55 males, mean age [SD] before SDR: 9 years 5 months [2 years 3 months]; Gross Motor Function Classification System level I: 18; II: 54; III: 17) received three-dimensional gait analyses at two time points (baseline and 1 year after SDR); their baseline gait patterns were classified. The analysis included the comparisons of (1) sagittal plane kinematic waveforms, the Gait Profile Score, and non-dimensional spatiotemporal parameters between the two time points, (2) the kinematic waveforms of both time points to those of typically developing children, and (3) composite impairment scores of spasticity, weakness, and selectivity between the two time points.

RESULTS

Overall, kinematics improved distally but deteriorated proximally in the entire sample, especially in genu recurvatum and crouch gait patterns. Jump gait showed the most improvements after SDR, followed by apparent equinus and crouch gait. Spasticity was reduced after SDR, but not at the expense of strength or selectivity.

INTERPRETATION

The potential merit of investigating short-term SDR effects on gait according to baseline gait patterns was shown, with an overview of changes after SDR that may facilitate patient-tailored treatment.

Selective dorsal rhizotomy: Analysis of two rootlet sectioning techniques

OBJECTIVE

To analyze and compare the efficacy of two selective dorsal rhizotomy (SDR) techniques with intraoperative neurophysiological monitoring, using instrumented three-dimensional gait analysis.

INTRODUCTION

SDR is a common, irreversible surgical treatment increasingly used to address gait disturbances in children with chronic non-progressive encephalopathy by reducing spasticity. Various techniques have been used, which mainly differ in the percentage of rootlets selected for sectioning. A greater proportion of rootlets sectioned leads to a more effective reduction of spasticity; however, there is a potential risk of unwanted neurological effects resulting from excessive deafferentation. While there is evidence of the short- and long-term benefits and complications of SDR, no studies have compared the effectiveness of each technique regarding gait function and preservation of the force-generating capacity of the muscles.

MATERIALS AND METHODS

Instrumented three-dimensional gait analysis was used to evaluate two groups of patients with spastic cerebral palsy treated by the same neurosurgeon in different time periods, initially using a classic technique (cutting 50% of the nerve rootlets) and subsequently a conservative technique (cutting no more than 33% the nerve rootlets).

RESULTS

In addition to an increase in knee joint range of motion (ROM), in children who underwent SDR with the conservative technique, a statistically significant increase (p = 0.04) in the net joint power developed by the ankle was observed. Patients who underwent SDR with the conservative technique developed a maximum net ankle joint power of 1.37 ± 0.61 (unit: W/BW), whereas those who were operated with the classic technique developed a maximum net ankle joint power of 0.98 ± 0.18 (unit: W/BW). The conservative group not only showed greater improvement in net ankle joint power but also demonstrated more significant enhancements in minimum knee flexion during the stance phase and knee extension at initial contact.

CONCLUSION

Our results show that both techniques led to a reduction in spasticity with a positive impact on the gait pattern. In addition, patients treated with the conservative technique were able to develop greater net ankle joint power, leading to a better scenario for rehabilitation and subsequent gait.

Gabapentin as part of a multimodal pain protocol for selective dorsal rhizotomy does not impact percentage of rootlets transected

PURPOSE

We aim to determine whether preoperatively initiated gabapentin for pain control impacts the percentage of rootlets cut during monitored, limited laminectomy selective dorsal rhizotomy (SDR) procedure.

METHODS

This retrospective cohort study includes participants with cerebral palsy who had SDR for treatment of spasticity between 2010 and 2019 at a single-institution tertiary care center. One-level laminectomy SDR aimed to evaluate the cauda equina roots from levels L2-S1 with EMG monitoring. Gabapentin titration began 3 weeks prior to SDR. Data was analyzed using simple linear regression. Thirty-one individuals met inclusion criteria. Mean age was 7 years, 4 months. Eighteen participants (58%) identified as male, 12 (39%) female, and one (3%) non-binary. Thirty (97%) had bilateral CP. Sixteen (52%) were GMFCS II, four (13%) GMFCS III, five (16%) GMFCS IV, and six (19%) GMFCS V.

RESULTS

Mean percentage of rootlets transected was 50.75% (SD 6.00, range 36.36-60.87). There was no relationship between the dose of gabapentin at time of SDR and percentage of rootlets cut with a linear regression slope of - 0.090 and an R2 of 0.012 (P = 0.56).

CONCLUSION

Results indicate that preoperative initiation of gabapentin did not impact the percentage of rootlets transected. Thus, gabapentin can be initiated prior to SDR at moderate dosages without impacting SDR surgical outcomes.

The long-term effects of aggressive spasticity reducing treatment, including selective dorsal rhizotomy, on joint kinematic outcomes of persons with cerebral palsy

BACKGROUND

Selective dorsal rhizotomy (SDR) creates a large and permanent reduction of spasticity for children with cerebral palsy (CP). Previous SDR outcomes studies have generally lacked appropriate control groups, had limited sample sizes, or reported short-term follow-up, limiting evidence for improvement in long-term gait function.

RESEARCH QUESTION

Does aggressive spasticity management for individuals with CP improve long-term gait kinematics (discrete joint kinematics) compared to a control group of individuals with CP with minimal spasticity management?

METHODS

This study was a secondary analysis - focused on joint-level kinematics - of a previous study evaluating the long-term outcomes of SDR. Two groups of participants were recruited based on a retrospectively completed baseline clinical gait study. One group received aggressive spasticity treatment including a selective dorsal rhizotomy (Yes-SDR group), while the other group had minimal spasticity management (No-SDR group). Both groups had orthopedic surgery treatment. Groups were matched on baseline spasticity. All participants prospectively returned for a follow-up gait study in young adulthood (greater than 21 years of age and at least 10 years after baseline). Change scores in discrete kinematic variables from baseline to follow-up were assessed using a linear model that included treatment arm (Yes-SDR, No-SDR), baseline age, and baseline kinematic value. For treatment arm, 5° and 5 Gait Deviation Index points were selected as thresholds to be considered a meaningful difference between treatment groups.

RESULTS

At follow-up, there were no meaningful differences in pelvis, hip, knee, or ankle kinematic variable changes between treatment arms. Max knee flexion - swing showed a moderate treatment effect for Yes-SDR, although it did not reach the defined threshold.

SIGNIFICANCE

Aggressive spasticity treatment does not result in meaningful differences in gait kinematics for persons with cerebral palsy in young adulthood compared to minimal spasticity management with both groups having orthopedic surgery.

Cerebral Palsy: Current Concepts and Practices in Musculoskeletal Care

Cerebral palsy is a neurologic disorder characterized by a spectrum of motor and cognitive deficits resulting from insults to the developing brain. The etiologies are numerous and likely multifactorial; an increasing portion of cases may be attributable to genetic causes, although the exact mechanisms responsible remain poorly understood. Major risk factors include intrauterine stroke and prematurity and neonatal infection, trauma, and hypoxia, which may occur in the prenatal, perinatal, or postnatal period. The Gross Motor Function Classification System (GMFCS) is a widely used tool to establish a child's level of function and to guide treatment; however, additional metrics are necessary to formulate long-term prognoses. Goals of care are to maximize function and independence, which directly correlate with overall quality of life, and family participation is key to establishing goals early in treatment. Nonpharmaceutical treatments include physical, occupational, and speech therapy, as well as bracing, equipment, and technology. There is a breadth of medical interventions for managing hypertonia, including medications, botulinum toxin injections, intrathecal baclofen pumps, and selective dorsal rhizotomy. Orthopedic interventions are indicated for symptomatic or progressive musculoskeletal sequelae. Treatments for dysplastic hips and/or hip instability range from soft tissue releases to bony procedures. Neuromuscular scoliosis is managed with posterior spinal fusion because bracing is ineffective against these rapidly progressive curves. The degree of care varies considerably depending on the child's baseline GMFCS level and functional capabilities, and early screening, diagnosis, and appropriate referrals are paramount to initiating early care and maximizing the child's quality of life.