Factors Associated With Short-Term Recovery Following Single-Event Multilevel Surgery for Children With Cerebral Palsy.

PURPOSE: To examine the role of multiple factors, including therapy dose, on recovery of mobility function during post-single-event multilevel surgery (SEMLS) rehabilitation in youth with cerebral palsy. METHODS: Several factors expected to influence postoperative change in Gross Motor Function Measure (GMFM) were examined: age, Gross Motor Function Classification System (GMFCS) level, cognition, number of osteotomies, surgical complications, medical comorbidities, number of therapy sessions, and preoperative measures of gait, balance, and gross motor function. RESULTS: Sixty-nine youth with cerebral palsy, GMFSC levels I-IV, who had undergone SEMLS and rehabilitation had on average 2.6 osteotomies and 89 postoperative therapy sessions. Fewer osteotomies, higher therapy dose, higher preoperative GMFM, and lower GMFM at postoperative admission were significant in determining GMFM change. CONCLUSIONS: The most relevant factors on post-SEMLS recovery were therapy dose, surgical burden, and level of gross motor function immediately before and after surgery.

Multi-Defect Detection in Additively Manufactured Lattice Structures Using 3D Electrical Resistance Tomography.

Cellular lattice structures possess high strength-to-weight ratios suitable for advanced lightweight engineering applications. However, their quality and mechanical performance can degrade because of defects introduced during manufacturing or in-service. Their complexity and small length scale features make defects difficult to detect using conventional nondestructive evaluation methods. Here we propose a current injection-based method, electrical resistance tomography (ERT), that can be used to detect damaged struts in conductive cellular lattice structures with their intrinsic electromechanical properties. The reconstructed conductivity distributions from ERT can reveal the severity and location of damaged struts without having to probe each strut. However, the low central sensitivity of ERT may result in image artifacts and inaccurate localization of damaged struts. To address this issue, this study introduces an absolute, high throughput, conductivity reconstruction algorithm for 3D ERT. The algorithm incorporates a strut-based normalized sensitivity map to compensate for lower interior sensitivity and suppresses reconstruction artifacts. Numerical simulations and experiments on fabricated representative cellular lattice structures were performed to verify the ability of ERT to quantitatively identify single and multiple damaged struts. The improved performance of this method compared with classical ERT was observed, based on greatly decreased imaging and reconstructed value errors.