1st Joint ESMAC-GCMAS Meeting - Análise de Marcha

O-56
THE EFFECT OF INCLUDING S2 ROOTLETS IN SELECTIVE DORSAL
RHIZOTOMY SURGERY
Schwartz, Michael H. 1,2 , Trost, Joyce P. 1 , Dunn, Mary E 1,2,3
Krach, Linda E 1,2 , Novacheck, Tom F. 1,2
1 Gillette Children’s Specialty Healthcare, St. Paul, USA
2 University of Minnesota, Minneapolis, USA
3 Shriner’s Hospital for Children - Twin Cities Unit, Minneapolis, USA
Summary and Conclusions
One and two year outcomes for selective dorsal rhizotomy surgery spanning L1-S1 and L1-S2
rootlets were essentially equivalent.
Introduction
Selective dorsal rhizotomy (SDR) has been used to reduce tone and increase function in
patients with cerebral palsy (CP). Surgical techniques vary, but the typical method involves
micro-dissection and electrophysiological testing. One element of the technique that has
remained a topic of debate is whether S2 level rootlets should be included. In a study of 85
subjects, Lang found that sparing S2 rootlets leaves “functionally impairing spasticity” in the
plantarflexors [1]. Lang’s study did not include quantitative gait measures as part of the
outcome. Conversely, Molenaers’ study of 12 subjects suggested that inclusion of S2 rootlets,
while producing 1-year outcomes equivalent to the S1 surgery, lead to loss of pelvic tilt, hip
extension and knee extension improvements 2 years post-SDR [2]. Molenaers’ study did not
report plantarflexor spasticity outcomes.
Statement of Clinical Significance
It is important to know whether or not S2 rootlets should be included in SDR surgery.
Methods
Following ethical approval subjects were retrospectively identified as follows: i) gait analysis
0-18 months before SDR (pre), 8-36 months after SDR (post #1), and 6-24 months after post
#1 (post #2), ii) SDR at Gillette Children’s Specialty Healthcare or Shriner’s Hospital for
Children–Twin Cities. Other clinical patient criteria and surgical details found in prior
publications [3]. Groups were created based on whether S2 rootlets had been included (S2) or
not (S1). A linear mixed model analysis was used to assess kinematic outcome measures over
three time points (pre, post #1, and post #2), while plantarflexor spasticity outcome pre→post
#1 was assessed using repeated measures ANOVA (SPSS 13.0.1, SPSS, Inc., Chicago, USA).
Results
There were 97 subjects with pre and initial follow-up (post #1) data and 27 subjects with
subsequent follow-up data (post #2) [Table 1]. Many subjects underwent orthopaedic surgery
following post #1, leading to the significant “drop out” rate.
All kinematic measures improved pre→post #1 and were unchanged from post #1→post #2,
except mean pelvic tilt, which worsened for both groups and both intervals. No differences
were found in the response of kinematic variables based on level of SDR (i.e. no pre/pst by
S1/S2 interactions); in fact the smallest p-value for an S1 vs. S2 interaction was p = 0.51.
Spasticity, as measured by Ashworth score, was reduced equally and significantly for both
groups during the pre→post #1 interval (S1: 3.1→1.7, S2: 3.0→1.6).
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