Selective Lumbosacral Dorsal Rhizotomy Immediately Caudal to the Conus Medullaris for Cerebral Palsy Spasticity(Neurosurgery 33:929-934, 1993)
Tae Sung Park, M.D., Patricia E. Gaffney, P.T., Bruce A. Kaufman, M.D., Michael C. Molleston, M.D.
Department of Neurology and Neurosurgery, St. Louis Children's Hospital, Washington University School of Medicine, St. Louis, Missouri, USA
We describe a variation of selective dorsal rhizotomy for spastic cerebral palsy that involves sectioning of the dorsal spinal roots immediately caudal to the conus medullaris. The operation entails an L1-L2 laminectomy, ultrasonographic localization of the conus medullaris, and partial deafferentation of the L1-S2 roots with electromyographic testing under an operating microscope. In 66 children with cerebral palsy, the operation reduced spasticity in the lower extremity without complications, e.g., motor weakness, neurogenic bladder, and sensory loss. It offers several important advantages over alternative techniques.
Keywords: Cerebral palsy, Conus medullaris, Dorsal rhizotomy
T.S. Park (a), George P. Vogler (b), Lawrence H. Phillips II (a), Bruce A. Kaufman (c), Madeleine R. Ortman (a), Stephanie M. McClure (a), Patricia E. Gaffney (a)
- Department of Neurology and Neurological Surgery, and St. Louis Children's Hospital, St. Louis, Mo., USA
- Division of Biostatistics, Washington University School of Medicine, St. Louis, Mo., USA
- Department of Neurology, University of Virginia Health Science Center, Charlottesville, Va., USA
In spastic diplegia of cerebral palsy, migration of the femoral head beyond a lateral edge of the acetabulum is a common orthopedic deformity and requires surgical treatment. We investigated whether selective dorsal rhizotomy for spastic diplegia halts or exacerbates lateral hip migration. The Reimers migration percentage computed from preoperative and postoperative hip radiographs was used as an index of the severity of lateral hip migration in all 134 hips of 67 children examined. At the time of rhizotomy, 38 patients were between 2 and 4 years of age and 29 were between 5 and 11 years of age. The follow-up period ranged from 6 to 10 months in 20 patients and from 15 to 46 months in 47 patients. Overall, the MP remained unchanged in 75% decreased in 17% and increased in 7%; thus, 93% of all hips examined were stable radiographically. Although most patients experienced postoperative hip stability, there was a significant trend for patients with greater preoperative migration to show decreased postoperative migration. The preoperative ambulatory status of patients had no impact on hip stability after dorsal rhizotomy. By the last follow-up, only 1 patient had undergone orthopedic operations for a persistent hip deformity. The results suggest that in children with spastic diplegia, selective dorsal rhizotomy halts lateral hip migration in the great majority of cases.
Keywords: Dorsal rhizotomy, Hip deformity, Spastic diplegia, Cerebral palsy
Robert C. Heim, M.D., T. S. Park, M.D., George P. Vogler, Ph.D., Bruce A. Kaufman, M.D., Michael J. Noetzel, M.D., And Madeleine R. Ortman, R.N.
Departments of Neurosurgery and Neurology, St. Louis Children's Hospital, and Division of Biostatistics, Washington University School of Medicine, St. Louis, Missouri, USA
Selective dorsal rhizotomy is increasingly used for management of spastic quadriplegic cerebral palsy but rates of hip stability following the operation have not been reported. Determining hip stability by radiographic measurement of lateral migration of the femoral head beyond a lateral edge of the acetabulum after dorsal rhizotomy allows an objective assessment of the outcome of the operation. This prospective study examined the effect of selective dorsal rhizotomy on lateral migration of the femoral head in 45 children with spastic quadriplegic cerebral palsy. The children ranged in age from 2 to 9 years (average 5 years 1 month) and were grouped according to their ages with 23 children in the 2- to 4-year-old group and 22 children in the 5- to 9-year-old group. Postoperative follow up ranged from 7 to 50 months (average 20 months). The Reimers migration percentage (MP), a measure of the lateral migration of the femoral head, was calculated from anteroposterior hip radiographs taken prior to the operation and at the last follow up examination. Of the 90 hips involved, 9% improved, 80% remained unchanged, and 11% worsened, yielding a radiographic stability rate of 89%. The hips with postrhizotomy worsening of the MP had an average preoperative MP of 14% (range 9% to 38%) and an average postoperative increase in MP of 18% (range 11% to 37%). Of the 45 children, four subsequently underwent unilateral derotational femoral osteotomies for persistent or worsening hip subluxation. There was a significant tendency for the MP to worsen in patients with lower prerhizotomy MP values (X2 = 20.74, df = 4, p = 0.001), but the age of patients and their ambulatory status at the time of rhizotomy had no bearing on postoperative hip stability. The data indicate that selective dorsal rhizotomy prevents progressive lateral migration of the femoral head in the majority of children who undergo the operation for spastic quadriplegia.
Keywords: cerebral palsy, dorsal rhizotomy, hip migration, spastic quadriplegia
Changes in Cognitive Performance in Children with Spastic Diplegic Cerebral Palsy following Selective Dorsal Rhizotomy
(Pediatr Neurosurg 1995;23:68-75)
Suzanne Craft (a, b), T.S. Park (c), Desiree A. White (a), Jeffrey Schatz (a), Michael Noetzel (c), Susan Arnold (c)
- Department of Psychology, Washington University, St. Louis, Mo., USA
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Wash., USA
- Department of Neurology and Neurological Surgery, and St. Louis Children's Hospital, Washington University School of Medicine, St. Louis, Mo., USA
Children with cerebral palsy who receive selective dorsal rhizotomy (SDR) for treatment of spasticity may show suprasegmental changes in upper limb function and control of speech musculature. Anecdotal reports suggest that suprasegmental effects may extend to cognitive functions such as attention and language. This study examined the performance of 16 children with spastic diplegic cerebral palsy on tests of visual attention and other cognitive functions I day prior to and 6 months following SDR. Children undergoing SDR were compared with 9 children with spastic diplegia, matched for severity of cerebral palsy and amount of therapy, who did not receive SDR, and 24 age- and sex-matched normal children tested at initial and 6-month follow-up sessions. Children with cerebral palsy treated with SDR showed disproportionately greater improvement in specific attentional and cognitive operations than either of the other groups. These results document cognitive changes following SDR which heretofore were reported anecdotally. This improvement may be due to improved mood, reduced physical discomfort, increased therapeutic intervention, or possible cortical effects of SDR.
Keywords: Cerebral palsy, Selective dorsal rhizotomy, Visual processing, Cognitive function, Inhibition
Michael R. Chicoine, M.D., Tae Sung Park, M.D., George P. Vogler, Ph.D., Bruce A. Kaufman, M.D.
Department of Neurological Surgery, St. Louis Children's Hospital (MRC, TSP, BAK), and Division of Biostatistics, Washington University School of Medicine (GPV), St. Louis, Missouri, USA
Serial evaluations were completed after selective dorsal rhizotomy on 90 children with spastic cerebral palsy to analyze whether age, the preoperative gait score, voluntary dorsiflexion at the ankle, the diagnosis (quadriplegia or diplegia), or the length of follow-up correlated with the ability to walk after rhizotomy. The preoperative gait score (P < 0.0001), the diagnosis (diplegia versus quadriplegia, P < 0.0001), unilateral dorsiflexion (P = 0.0029), and bilateral dorsiflexion (P < 0.0001) were significant predictors of the maximal postoperative gait score in the univariate regression analysis, but only the preoperative gait score (P < 0.0001) and the diagnosis (P = 0.0015) retained significant predictive power in the multivariate analysis. These data suggest that the preoperative gait score and the diagnosis are the strongest predictors of ability to walk after selective dorsal rhizotomy. Dorsiflexion demonstrated predictive power only in the univariate model, suggesting that it might have some prognostic value but less than the preoperative gait score or the diagnosis.
Keywords: Cerebral palsy, Dorsiflexion, Gait, Selective dorsal rhizotomy, Walking
Michael R. Chicoine, M.D., T.S. Park, M.D., And Bruce A. Kaufman, M.D.
Department of Neurosurgery, Center for Cerebral Palsy Spasticity, St. Louis Children 's Hospital, Washington University School of Medicine, St. Louis, Missouri, USA
If the spasticity of cerebral palsy (CP) is reduced in children at a young age by selective dorsal rhizotomy, the incidence of lower-extremity deformities requiring orthopedic surgery may be reduced; however, this has never been investigated in detail. The authors examined the effects of selective dorsal rhizotomy on rates of lower-extremity orthopedic surgery in 178 children with CP. Age at selective dorsal rhizotomy ranged from 2 to 19.3 years (mean 5.5 years) with follow-up intervals ranging from 24 to 70 months (mean 44 months). Spastic CP was classified as quadriplegia (33%), diplegia (65%), and hemiplegia (2%). To assess the effects of early versus late rhizotomy on rates of orthopedic surgery, patients were grouped as follows: Group I underwent rhizotomy between 2 and 4 years of age (54 patients), and Group II underwent rhizotomy between 5 and 19 years of age (124 patients). Comparison of Kaplan-Meier plots of lifetime orthopedic surgery rates revealed that Group n underwent orthopedic surgery at a higher rate than Group I (p = 0.037). Analysis by procedure type revealed higher orthopedic surgery rates in Group II than Group I for heel cord releases (p = 0.0025), adductor releases (p = 0.018), and hamstring releases (p = 0.02). Orthopedic surgery rates were no higher for Group II compared to Group I for ankle/foot operations (p = 0.023), femoral osteotomy (p = 0.25), iliopsoas releases (p = 0.35), and "other" operations (p = 0.013). The data indicate that early rhizotomy reduces the need for orthopedic surgery for heel cord, hamstring, and adductor releases.
Keywords: cerebral palsy, dorsal rhizotomy, orthopedic operations, spastic diplegia, spastic quadriplegia
Jack R. Engsberg, Kenneth S. Olree, Sandy A. Ross, and Tae S. Park
Human Performance Laboratory, Barnes-Jewish and St. Louis Children's Hospitals, Washington University School of Medicine, St. Louis, MO, USA
This investigation quantified maximum active resultant joint torques in children with spastic diplegia cerebral palsy and nondisabled children. An isokinetic dynamometer rotated the limb (10¡/s) while the resultant knee joint torques (both assistive and resistive) during knee extension and flexion in 6 nondisabled children and 26 children with cerebral palsy were recorded. Torque-angle data were processed to calculate maximum values during extension and flexion and work done during the movements. An independent t test determined if significant differences existed between groups (p < .05). Maximum extensor and maximum flexor torques and work during extension and flexion were significantly less for the children with cerebral palsy. Results supported previously published research indicating that children with spastic diplegia were weaker than nondisabled children. Additional information regarding the weakness of the children with spastic diplegia near the end range of extension motion is presented.
Keywords: strength, spastic diplegia, dynamometer, flexion, extension
Jack R. Engsberg, Ph.D., Kenneth S. Olree, M.S., Sandy A. Ross, M.H.S., P.T., P.C.S., And T. S. Park, M.D.
Human Performance Laboratory, Barnes-Jewish and St Louis Children's Hospitals St. Louis, Missouri, USA; and Center for Cerebral Palsy Spasticity, Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri, USA
Goal: The goal of this investigation was to quantify changes in hamstring muscle spasticity and strength in children with cerebral palsy (CP) as a function of their having undergone a selective dorsal rhizotomy.
Method: Nineteen children with CP (CP group) and six children with able bodies (AB group) underwent testing with a dynamometer. For the spasticity measure, the dynamometer measured the resistive torque of the hamstring muscles during passive knee extension at four different speeds. Torque-angle data were processed to calculate the work done by the machine to extend the knee for each speed. Linear regression was used to calculate the slope of the line of best fit for the work-velocity data. The slope simultaneously encompassed three key elements associated with spasticity (velocity, resistance, and stretch) and was considered the measure of spasticity. For the strength test, the dynamometer moved the leg from full knee extension to flexion while a maximum concentric contraction of the hamstring muscles was performed. Torque-angle data were processed to calculate the work done on the machine by the child. Hamstring spasticity values for the CP group were significantly greater than similar values for the AB group prior to surgery; however, they were not significantly different after surgery. Hamstring strength values for the CP group remained significantly less than those for the AB group after surgery, but were significantly increased relative to their presurgery values.
Conclusions. The results of spasticity testing in the present investigation agreed with those of previous studies, indicating a reduction in spasticity for the CP group. The results of strength testing did not agree with those in the previous literature: a significant increase in strength was observed for the CP group.
Keywords: cerebral palsy, spasticity, rhizotomy, strength, dynamometer, hamstring