PURPOSE:
Our goal was to check whether the recently modified rhizotomy protocol that could be effectively used to guide selective dorsal rhizotomy (SL-SDR) of a single-level approach for the treatment of spastic hemiplegic cases, mainly releasing those spastic muscles (target muscles) noted before surgery, in their lower limbs were still applicable in cases of spastic quadriplegic or diplegic cerebral palsy (cerebral palsy) in the pediatric population.

METHODS:
In the current study, we retrospectively conducted a cohort review of cases under the age of 14 who have been diagnosed with spastic quadraplegia or diplegic CP who have passed our modified SL-SDR according to the protocol in the Department of Neurosurgery, Shanghai Children's Hospital since July 2016, to November 2017 with an intensive rehabilitation program lasting at least 12 months (up to the level of GMFCS). Clinical data, including demographic data, intraoperative interpretation of EMG responses and a corresponding assessment of cases included, were taken from the database. Criteria for inclusion and exclusion have been established for the selection of patients in the current study. Muscle tone (modified Ashworth scale) and the strength of these spastic muscles (muscle strength assessment scale), the range of movement (ROM) of the joints involved, the level of the gross-motor function classification system (GMFCS) and the indicator of gross-motor function of 66 points (GMFM-66), the assessment of these cases was at the center of our attention.

RESULTS:
Our study included 86 suitable cases (62 boys). Among these patients, 61.6% were four-legged. Before the operation, almost 2/3 of our cases were with levels GMFCS II and III. The average age at the time of surgery in these cases was 6.2 (3.5-12) years. Preoperative assessment noted 582 target muscles in these patients. The number of nerve roots tested during the SDR procedure was between 52 and 84 in all our cases, with an average of 66.5 ± 6.7 / case.
Among the tested (5721 in 86 cases), 47.9% (2,740) were identified as sensory roots associated with the lower extremities. Our protocol successfully differentiated sensory roots, which were believed to be related to the spasticity of target muscles in all our 86 cases (in the range from 3 to 21).
According to our protocol, 871 spinal nerve roots were cut by 50% and 78 by 75%. The muscle tone of these target muscles decreased significantly immediately after the SL-SDR procedure (3 weeks after and before surgery, 1.7 ± 0.5 against 2.6 ± 0.7). After an intensive rehabilitation program for 19.9 ± 6.0 months, muscle tone continued to decline to 1.4 ± 0.5. With a decrease in muscle tone, the strength of these target muscles in our cases has improved significantly when achieving statistical significance (3.9 ± 1.0 at the time of the last observation against 3.3 ± 0.8 before surgery), as well as ROM.
An increase in GMFCS and GMFM-66 was observed during the last observation by an average of 0.4 ± 0.6 and 6.1 ± 3.2, respectively, compared to that in the period before the operation. In 81 cases with their preoperative levels, GMFCS from II to V 27 (33.3%) presented an improvement in the increase in the level of GMFCS, of which 4 (4.9%) even increased by 2 levels. The best results for increasing the GMFCS level were observed in cases with preoperative levels II and III compared to levels with levels IV and V (24/57 against 3/24). The percentage of increase in cases under 6 years of age for surgery was significantly higher than in older ones (23/56 versus 4/25). Cases with their preoperative score GMFM-66 ≥ 50 had a greater increase in GMFM-66 compared to those less (7.1 ± 3.4 versus 5.1 ± 2.8). Meanwhile, improvements in indicators were detected when SDR was performed at a younger age (6.9 ± 3.3 in the case of ≤ 6 years versus 4.7 ± 2.7 in case of > 6 years). The current study did not record persistent complications associated with the operation.

CONCLUSION:
SL-SDR, when we were guided by our new modified rhizotomy protocol, are still feasible for the treatment of CP cases in children with