Selective Dorsal Rhizotomy for the Treatment of Gait Dysfunction in Cerebral Palsy: A Critical Analysis Review

Understanding muscle energy expenditure variations following selective dorsal rhizotomy while maintaining consistent energy consumption

Increased energy demands during walking is a recurrent issue for children with cerebral palsy (CP). Given the high incidence of spasticity in these children, several authors have analyzed the impact of selective dorsal rhizotomy (SDR) on energy consumption during walking, typically showing minimal changes post-SDR. To further investigate muscle behavior after SDR, our recent study identified alterations in individual muscle force production without changes in muscle activation during walking. This suggests that children with CP may experience a more favorable dynamic scenario for developing sub-maximal muscle forces after SDR, due to reduced spasticity unlocking joint movement. Thus, this raises questions about whether these changes in muscle force production could lead to increased muscle energy expenditure, which may not be fully reflected in overall energy consumption. The aim of this study was to build upon our previous research on muscle behavior after SDR by evaluating the surgery's impact on individual muscle energy expenditure during walking, using neuro-musculoskeletal simulations. Our research compared two matched groups comprising 81 children with CP: those who underwent SDR and those who did not. Our results showed no significant changes in overall energy consumption or total muscle energy expenditure in either group post-surgery. However, we observed alterations in individual muscle energy expenditure during walking in the SDR group compared to children with CP who received other treatments. Compared to the findings from our first study, we observed a significant decrease in spasticity of the plantarflexor muscles, an improvement in ankle joint angle, an increase in individual muscle force during walking, and no statistically significant changes in energy expenditure of the gastrocnemius and soleus muscles post-SDR. These findings, along with the absence of changes in muscle activity post-SDR, support the hypothesis that muscle tissue alterations contribute to energy deficits observed in children with CP during walking.

Comparison of outcomes following surgical intervention and inpatient rehabilitation stays in children with cerebral palsy

INTRODUCTION

Literature is limited on functional outcomes in children with cerebral palsy (CP) following surgical procedures and a subsequent inpatient rehabilitation unit (IRU) stay.

OBJECTIVE

To compare functional outcomes and length of stay (LOS) in children with CP following a surgical procedure and IRU stay based on the surgical procedure performed, pattern of involvement, etiology, and Gross Motor Function Classification System (GMFCS) level.

DESIGN

Retrospective cohort study.

SETTING

Tertiary care pediatrics.

PARTICIPANTS

Pediatric patients with CP who underwent one of three surgical procedures followed by an IRU stay.

INTERVENTIONS

Selective dorsal rhizotomy (SDR), single-event multilevel orthopedic surgery (SEMLS), or intrathecal baclofen (ITB) pump implantation and subsequent IRU stay.

MAIN OUTCOME MEASURES

IRU LOS, Functional Independence Measure for Children (WeeFIM) total score, sub-scores, and efficiency.

RESULTS

Children undergoing SDR had a longer LOS (p ≤ .015). Children with spastic diplegia, GMFCS level II, and prematurity-based CP had higher WeeFIM efficiency scores (p ≤ .046, ≤.021, and .034 respectively). Greater changes in WeeFIM™ scores were associated with spastic diplegia, SDR, GMFCS level II, longer LOS, and higher admission scores (p ≤ .045).

CONCLUSIONS

Although statistically and functionally significant improvements in children with CP following surgical interventions and an IRU stay were seen, those with higher WeeFIM change scores tended to have spastic diplegia, to have undergone SDR, GMFCS level II, longer LOS, and higher admission scores.

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.

Selective dorsal rhizotomy and its effect on muscle force during walking: A comprehensive study

Selective dorsal rhizotomy (SDR) is commonly used to permanently reduce spasticity in children with cerebral palsy (CP). However, studies have yielded varying results regarding muscle strength and activity after SDR. Some studies indicate weakness or no changes, while a recent study using NMSK simulations demonstrates improvements in muscle forces during walking. These findings suggest that SDR may alleviate spasticity, reducing dynamic muscle constraints and enhancing muscle force without altering muscle activity during walking in children with CP. In this study, we combined NMSK simulations with physical examinations to assess children with CP who underwent SDR, comparing them to well-matched peers who did not undergo the procedure. Each group (SDR and No-SDR) included 81 children, with pre- and post-SDR assessments. Both groups were well-matched in terms of demographics, clinical characteristics, and gait parameters. The results of the physical examination indicate that SDR significantly reduces spasticity without impacting muscle strength. Furthermore, our findings show no significant differences in gait deviation index improvements and walking speed between the two groups. Additionally, there were no statistically significant changes in muscle activity during walking before and after SDR for both groups. NMSK results demonstrate a significant increase in muscle force in the semimembranosus and calf muscles during walking, compared to children with CP who received other clinical treatments. Our findings confirm that although SDR does not significantly impact muscle strength compared to other treatments, it creates a more favorable dynamic environment for suboptimal muscle force production, which is essential for walking.

Dorsal Rhizotomy in the Pediatric Patient

SUMMARY

The majority of cases of dorsal rhizotomy surgeries in children are done to improve the spasticity associated with cerebral palsy, and more recent techniques are selective in nature and referred to as selective dorsal rhizotomy (SDR). The techniques applied to selective dorsal rhizotomy surgery has changed since it was first described and continues to undergo modifications. Approaches to surgery and monitoring vary slightly among centers. This article provides a review of the rationale, variety of surgical approaches, and intraoperative neurophysiologic monitoring methods used along with discussion of the risks, complications and outcomes in these surgeries.

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.

The medium-term effects of selective dorsal rhizotomy on gait compared to a matched cerebral palsy non-SDR group: A follow-up study

BACKGROUND

Selective dorsal rhizotomy (SDR) has been shown to improve gait in the short-term in children with cerebral palsy (CP). Further study is needed to look at the trajectory of outcomes over the longer-term.

RESEARCH QUESTION

What are the medium-term effects of SDR on gait compared to a matched CP non-SDR group?

METHODS

Participants underwent SDR at mean age 6.3 years and completed baseline, 1-year and 5-year follow-up gait analyses. Non-SDR participants were matched at baseline. Differences were assessed within and between groups. Kinematic variables were analysed using Statistical non-Parametric Mapping (SnPM). Other gait and clinical data were analysed using Friedman's one-way repeated measure analysis of variance and a Mann-Whitney U-test.

RESULTS

The initial SDR group consisted of 29 participants, reducing to 22 at 5-year follow-up. Of these, 15 (68 %) had orthopaedic surgeries either concurrent with or in the intervening period since the SDR, mean 3.3 procedures per participant. The initial non- SDR group had 18 participants, reducing to 17 at 5-year follow-up. Of these, 13 (76 %) had orthopaedic surgeries, mean 5.7 procedures. At 1-year follow-up the SDR group had significantly improved knee extension, ankle dorsiflexion, foot progression, Gait Deviation Index, and normalised step length compared to baseline, p < 0.05, and outcomes were maintained at 5-years. At 1-year follow-up the non-SDR group kinematic patterns were unchanged, but at 5-year follow-up this group demonstrated significantly improved knee extension, ankle dorsiflexion and foot progression. There were no significant kinematic differences between the SDR and the non-SDR group at medium-term follow-up.

SIGNIFICANCE

We have documented the trajectory of gait outcomes post-SDR over 3 assessments and found that short-term gait changes endured in the medium-term. However, kinematic changes were similar to a non-SDR group undergoing routine and orthopaedic care. These outcomes are important to guide surgical decision making and to manage treatment goals and expectations.

Modified desk height helps children with cerebral palsy perform sit-to-stand

Aim: Children with cerebral palsy (CP) have difficulties performing activities that require the use of fundamental motor skills such as sit-to-stand (STS). In this study, we used a height adjustable chair and desk to investigate the role of desk support in STS and how it might benefit children with CP. Methods: Seventeen typically developing children (TDC), average age = 9.7 years, and 28 children with CP (Gross Motor Function Classification System [GMFCS] I and II), average age = 10.3 years, participated in the test. Elapsed time and body sway were measured using a pressure mat and load cell while each child performed a STS task. Two different desk heights were tested for time consumption and sway under the condition of hands-on-desk and arms-crossed. Results: We found that the elapsed time of hands-on-desk with the elbow flexion height was the shortest (p < 0.05). Sway amount was also significantly reduced for all children when they used the table for STS (p < 0.05). Conclusion: Results of this study may be a useful reference in rehabilitation training and designing a desk height beneficial for children with CP.Implications for RehabilitationBetter performance of sit-to-stand for a child with cerebral palsy could be made by a desk supportElapsed time during preparation period for sit-to-stand could be reduced by desk support for all CP childrenSway amount during sit-to-stand could be reduced by desk support, especially for the CP children with GMFCS level IIDesk height is an important parameter and should be studied in detail.

Effects of Selective Dorsal Rhizotomy on Ankle Joint Function in Patients With Cerebral Palsy

Selective dorsal rhizotomy (SDR) is a neurosurgical technique performed to reduce muscle spasticity and improve motor functions in children with cerebral palsy (CP). In long term, muscle contractures were observed even after SDR. To better understand what is contributing to contracture formation, it is necessary to assess the effects of SDR on joint stiffness. We hypothesized that ankle passive range of motion (ROM) increases and the quasi-stiffness of the ankle joint decreases after SDR in children with CP. This retrospective study included 10 children with diplegic CP (median age 6 years 2 months) who had undergone SDR and for whom gait analysis data were collected 3 months before (Pre-SDR) and 13 months after (Post-SDR) surgery. Additional to clinical measures, ankle quasi-stiffness (the slope of the ankle moment vs. ankle angle plot) was analyzed from gait data. Passive ankle ROM at 0° (p < 0.0001) and 90° knee angles (p < 0.0001) increased after SDR. Dynamic EMG analysis showed improved phasic gastrocnemius activity (p < 0.0001). Equinus gait was improved with the reduction of peak plantar flexion (p < 0.0001), as well as an increase in peak dorsiflexion (p = 0.006) during walking was observed. Ankle joint quasi-stiffness (Pre- and post-SDR median = 0.056 Nm/kg/° and 0.051 Nm/kg/°, and interquartile range: 0.031 Nm/kg/° and 0.019 Nm/kg/°, respectively) decreased significantly (p = 0.0017) after SDR. Moreover, even though the total time of the gait cycle did not change (p = 0.99), the time interval from maximum dorsiflexion to maximum plantar flexion (Pre- and post-SDR median = 0.125 s and 0.156 s, and interquartile range: 0.153 and 0.253 s, respectively) increased significantly (p = 0.0068) after SDR. In conclusion, the decreased ankle quasi-stiffness and the enhanced time interval in the gait cycle due to SDR indicate better motor control and joint stability. Our findings suggest that the long-term contracture formation occurring even after surgical interventions may be related to the stiffening of non-contractile structures.