Predicting functional change from preintervention measures in selective dorsal rhizotomy

Abstract

Object-In this investigation the authors attempted to predict change in function following selective dorsal rhizotomy (SDR) and intensive physical therapy in patients with spastic diplegic cerebral palsy (CP) based on multidomain preintervention measures.Methods-Data pertaining to 22 children with CP were collected before the SDR and again 20 months afterward. Although equations for predicting change in gait speed and function (such as the Gross Motor Function Measure) were derived, the 95% confidence interval (CI) widths were too broad to make accurate predictions that were clinically useful outside the study group.Conclusions-Future work should be focused on developing additional measures such as lowerextremity motor control and balance in an attempt to reduce the CIs to more clinically relevant values. Keywords cerebral palsy; gait spasticity; strength; rhizotomy; predictive measure; pediatric neurosurgery Selective dorsal rhizotomy is a surgical procedure used to treat patients with CP that involves partial sensory deafferentation at the L1-S2 levels. 22 The effectiveness of the surgery has been reported in randomized 19,28,30 and nonrandomized 8 clinical studies. Despite the evidence of its effectiveness, it is important to note that variability exists within the patient groups and not all patients exhibit the same degree of improvement from the SDR. For example, although in one patient in our investigation the GMFM score improved from 75% preoperatively to 86% at 20 months postoperatively (an 11-point improvement), the GMFM score in another patient changed from 73% preoperatively to 72% at 20 months postoperatively (a one-point decrease). 8 Relative to gait speed, one patient's speed improved from 61 cm/second preoperatively to 121 cm/second at 20 months postoperatively (a 60-cm/second improvement), whereas another patient's gait speed changed from 109 cm/second preoperatively to 102 cm/second at 20 months postoperatively (a 7-cm/second decrease).Being able to predict preoperatively which patients will have the greatest improvements in GMFM, gait speed, or some other outcome measure would be extremely valuable for them and Address reprint requests to: Jack R. Engsberg, Ph.D., Department of Physical Therapy, 3437 Caroline Street, Saint Louis University, St. Louis, Missouri 63104. email: E-mail: jengsber@slu.edu. their parents when considering the SDR. Previously, authors of two investigations have attempted to predict postoperative outcomes based on preoperative data. 2,16 Chicoine and colleagues 2 attempted to predict walking ability after SDR using a series of preoperative variables (subjective gait score, dorsiflexion ability, and diagnosis). The results of their multivariate regression analysis indicated that gait score and diagnosis (spastic diplegia or quadriplegia) had significant predictive capability, explaining 78% of the variance in predicting the postoperative gait score. Despite the large amount of explained variance in their patients, the investigators were hesitant to suggest that the...

Selection criteria for selective dorsal rhizotomy in children with spastic cerebral palsy: a systematic review of the literature

“…None of these articles was classified as level I or V; five articles were rated as level II, 13 as level III, and 34 as level IV . Table gives an overview of the background information, while Table reports the results of the appraisal of the selected level II and level III articles.…”

The effect of lower extremity selective voluntary motor control on interjoint coordination during gait in children with spastic diplegic cerebral palsy

“…Children with CP who have reduced ability to develop the selective motor control necessary for skilled movements may develop movement strategies that retain primitive coupled patterns to various degrees. Preliminary evidence suggests that SVMC ability may be an important factor affecting functional movement tasks [7,8] and may be predictive of improvement following interventions [9]. Despite these clinical findings, the role of SVMC has not been explored as a factor that can affect biomechanics during walking in children with CP.…”

Selective Control Assessment of the Lower Extremity (SCALE): development, validation, and interrater reliability of a clinical tool for patients with cerebral palsy

“…1,2 Assessment of selective motor control in lower extremities in patients with CP has received little attention, despite growing support for it as a predictive factor of functional ability. [1][2][3][4] Selective motor control has been defined as '... the ability to isolate the activation of muscles in a selected pattern in response to demands of a voluntary movement or posture.' 5 The term 'selective voluntary motor control' (SVMC) differentiates the deliberate performance of isolated movements upon request from habitual selective muscle activation during functional tasks, such as walking.…”