Factors related to better outcomes after single-event multilevel surgery (SEMLS) in patients with cerebral palsy

Background: Good outcomes have been described after single-event multilevel surgery (SEMLS) in cerebral palsy (CP); however, there is limited evidence regarding factors influencing them. Research question: What were the factors related to kinematic outcomes after SEMLS in the present study? Methods: Two hundred and fifty-eight patients with spastic diplegic CP, GMFCS I-III, who underwent SEMLS and had done pre and post-operative gait analyses were included in the SEMLS Group (SEMLS-G). A second search was performed in the same database looking for patients to compose the Control Group (CG), and 88 subjects, with at least two gait analyses and with no surgical intervention between tests, were identified. Demographic data, GDI and GPS (Gait Profile Score) were analyzed in both groups, and the results compared. A second evaluation was performed in the SEMLS-G in order to identify the influence of age, gender, follow-up time, preoperative GDI, GMFCS and gait velocity on results. Results: The GDI (51.3-58.4) and GPS (2.5 degrees) improvement occurred only in SEMLS-G (p < 0.001). On sagittal plane, there was an improvement at the knee and ankle levels in SEMLS-G, whereas the pelvic alignment improved in the CG. In SEMLS-G, patients with improvement on GDI > 10 points had lower pre-operative GDI (46.15) than other groups (p < 0.001). In addition, patients with reduction on GDI after intervention had lower pre-operative gait velocity than subjects with improvement >10 points (p = 0. 01). The increase on GDI after SEMLS was greater in patients GMFCS I and II than GMFCS III (p = 0.003). There was a negative effect of GMFCS III on GDI improvement after intervention (p = 0.014). Significance: Lower pre-operative GDI, higher baseline gait velocity and GMFCS levels I and II were related to better outcomes after SEMLS in the present study. On the other hand, patients GMFCS III were more susceptible to deteriorate after SEMLS.