Changes in hip geometry after selective dorsal rhizotomy in children with cerebral palsy

Does intrathecal baclofen therapy decrease the progression of hip displacement in young patients with cerebral palsy?

AIM

To evaluate the effects of intrathecal baclofen pump (ITBP) therapy on hip dysplasia in young patients with cerebral palsy (CP).

METHOD

This was a retrospective cohort series of prospectively collected data. Inclusion criteria were all patients with CP in Gross Motor Function Classification System (GMFCS) levels IV or V who underwent ITBP placement under 8 years old with at least 5 years of follow-up. Thirty-four patients were matched to a control group of 71 patients based on GMFCS level, motor type, medical comorbidities, worst hip migration percentage at ITBP placement, age, and Modified Ashworth scale scores. Patients were followed for at least 5 years or until they had hip reconstructive surgery. The primary outcome was the development of hip displacement as measured by the migration percentage at the latest follow-up or the preoperative migration percentage before hip reconstruction.

RESULTS

The migration percentage at last follow-up was not statistically different between groups (ITBP: 36.2%, non-ITBP: 44.4%, p = 0.14). The rates of future preventative, reconstructive, and recurrent hip surgery were not different between groups.

INTERPRETATION

The use of ITBP as an early treatment of spasticity did not alter the natural history of progressive hip displacement in non-ambulatory patients with CP and hip displacement is likely multifactorial, not solely due to spasticity.

Comparison of kinematic parameters of children gait obtained by inverse and direct models

The purpose of this study is to compare differences between kinematic parameters of pediatric gait obtained by direct kinematics (DK) (Plug-in-Gait) and inverse kinematics (IK) (AnyBody) models. Seventeen healthy children participated in this study. Both lower extremities were examined using a Vicon 8-camera motion capture system and a force plate. Angles of the hip, knee, and ankle joints were obtained based on DK and IK models, and ranges of motion (ROMs) were identified from them. The standard error of measurement, root-mean-squared error, correlation r, and magnitude-phase (MP) metrics were calculated to compare differences between the models’ outcomes. The determined standard error of measurement between ROMs from the DK and IK models ranged from 0.34° to 0.58°. A significant difference was found in the ROMs with the exception of the left hip’s internal/external rotation. The mean RMSE of all joints’ amplitudes exceeded the clinical significance limit and was 13.6 ± 4.0°. The best curve angles matching nature were found in the sagittal plane, where r was 0.79 to 0.83 and MP metrics were 0.05 to 0.30. The kinematic parameters of pediatric gait obtained by IK and DK differ significantly. Preferably, all of the results obtained by DK must be validated/verified by IK, in order to achieve a more accurate functional assessment of the individual. Furthermore, the use of IK expands the capabilities of gait analysis and allows for kinetic characterisation.

The progress in the treatment of spastic cerebral palsy with selective dorsal rhizotomy (SDR)

Spasticity is the main disabling clinical manifestation of children with cerebral palsy (CP). Selective dorsal rhizotomy (SDR) has been performed for the treatment of spastic CP in Asia for quite some time from 1990. The purpose of this review is to discuss the historical origin and development of SDR. Our goal here is to identify the current patient selection criteria for SDR and to point out indications and contraindications based on the patients with CP, age from 2 to 18 years-old, over 6000 cases, who received SDR surgery with spasticity of muscle tension more than 3 degrees in our center. We also discuss evidence-based approaches on how to evaluate postoperative patient outcomes of SDR and how complications can be avoided. Finally, we mention progress made in terms of SDR technical advances and how improvements can be made in the future. In conclusion, SDR surgery is a reliable way to improve outcomes of patients with spastic CP and can be done carefully in patients as long as stringent selection criteria are used. However, more research and technological advancements are needed to help address associated complications.

Relationship between muscular and bony anatomy in native hips: a theoretical background for approach-specific implant positioning

INTRODUCTION:

The aim of this study was to analyse the relationship between bony joint orientation and the distribution of hip musculature.

METHODS:

The bone anatomy of the hip (femoral antetorsion (AT), acetabular anteversion (AV), and combined anteversion (AV/AT)) and the muscle volume of the gluteal muscles and the tensor fasciae latae were analysed bilaterally using computed tomography data of 49 patients. Muscle force direction (MFD) was determined for each muscle. The total MFD of the hip musculature was calculated and then correlated with the bony anatomy.

RESULTS:

The mean AV, AT, and AV/AT were 21.9° ± 5.9°, 7.22° ± 7.4°, and 29.2° ± 9°, respectively. We found the following mean muscle volumes: gluteus maximus: 780 ± 227 cm3, gluteus medius: 322 ± 82 cm3, gluteus minimus: 85 ± 20 cm3, and tensor fasciae latae: 68 ± 22 cm3. The mean MFD was 18.92° ± 1.29°. We found a uniform distribution of the musculature that was not correlated with the bone anatomy.

CONCLUSION:

This study highlights the variability in native acetabular and femoral anatomy and that bone hip anatomy does not correlate with the distribution of hip musculature. Although native acetabular anteversion matches the suggested targets for cup insertion, native combined anteversion is not related to current implant insertion targets. Understanding native muscular anatomy and the alterations that occur with different surgical approaches can serve as an explanatory model for THAs that has become unstable despite the components being implanted within the safe zone.

Evidence Supporting Selective Dorsal Rhizotomy for Treatment of Spastic Cerebral Palsy

The objective of this review is to analyze the evidence supporting selective dorsal rhizotomy (SDR) for the treatment of spastic cerebral palsy (CP). We reviewed 85 outcome studies from 12 countries between 1990 and 2017. The published results are overwhelmingly supportive of SDR, and 39 studies form a basis for this review. Also included is some of the clinical experience of the senior author.

The results show that SDR plus postoperative physiotherapy (PT) improved gait, functional independence, and self-care in children with spastic diplegia. In adults with a follow-up of 20 to 28 years, the early improvements after childhood SDR were sustained and improved quality of life. Furthermore, majority of the adults who underwent SDR as children would recommend SDR to others. On the clinical side, while SDRs through multilevel laminectomies or laminoplasty were associated with spinal deformities (i.e., scoliosis, hyperlordosis, kyphosis, spondylolisthesis, spondylolysis, and nonhealing of laminoplasty), SDRs through a single level laminectomy prevented SDR-related spinal problems. The outcomes of SDR specific to spastic quadriplegia require further investigation because of the relatively small patient population with quadriplegia. Lastly, we found that SDR can prevent or reverse premature aging in adolescents and adults with spastic diplegia. In conclusion, the evidence supporting the efficacy of SDR is strong, and SDR is a well-established option for spasticity management in spastic CP.

Prevention of hip displacement in children with cerebral palsy: a systematic review

AIM

To conduct a systematic review and evaluate the quality of evidence for interventions to prevent hip displacement in children with cerebral palsy (CP).

METHOD

A systematic review was performed using American Academy of Cerebral Palsy and Developmental Medicine (AACPDM) and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology. Searches were completed in seven electronic databases. Studies were included if participants had CP and the effectiveness of the intervention was reported using a radiological measure. Results of orthopaedic surgical interventions were excluded.

RESULTS

Twenty-four studies fulfilled the inclusion criteria (4 botulinum neurotoxin A; 2 botulinum neurotoxin A and bracing; 1 complementary and alternative medicine; 1 intrathecal baclofen; 1 obturator nerve block; 8 positioning; 7 selective dorsal rhizotomy). There was significant variability in treatment dosages, participant characteristics, and duration of follow-up among the studies. Overall, the level of evidence was low. No intervention in this review demonstrated a large treatment effect on hip displacement.

INTERPRETATION

The level and quality of evidence for all interventions aimed at slowing or preventing hip displacement is low. There is currently insufficient evidence to support or refute the use of the identified interventions to prevent hip displacement or dislocation in children and young people with CP.

WHAT THIS PAPER ADDS

High-quality evidence on prevention of hip displacement is lacking. No recommendations can be made for preventing hip displacement in children with cerebral palsy because of poor-quality evidence. High-quality, prospective, longitudinal studies investigating the impact of interventions on hip displacement are required.