Stiff-knee gait is a troublesome movement disorder among children with cerebral palsy (CP), where peak swing phase knee flexion is diminished due to over-activity of the rectus femoris muscle. A common treatment for stiff-knee gait, rectus femoris transfer surgery, moves the muscle's distal tendon from the patella to the sartorius insertion on the tibia. As a biarticular muscle, rectus femoris may play a role in motor control and have unrecognized benefits for maintaining balance. We used musculoskeletal modeling, neuromuscular control, and forward dynamic simulation to investigate the role of rectus femoris tendon transfer surgery on balance recovery after support-surface perturbations for children with CP adopting two different crouched postures. We combined both high-level supraspinal and low-level spinal signals to generate 92 muscle excitations for tracking experimental whole body center of mass positions and velocities. Stability during balance recovery was evaluated by the minimum distance between the extrapolated center of mass and base of support boundary (bmin) and the minimum time to reach the boundary (TtBmin). The balance recovery of pre-surgical simulations (bmin=2.3+1.1cm, TtBmin=0.2+0.1s) were different (p=0.02), on average, than post-surgical simulations (bmin=-4.9+11.4cm, TtBmin=-0.1+0.3s) of rectus femoris transfers. The moderate crouch simulations (bmin=2.4+0.4cm, TtBmin=0.2+0.03s) were more stable than the mild crouch simulations (bmin=1.2+0.3cm, TtBmin=0.1+0.02s) following anterior translations of the support surface. These findings suggest that tendon transfer of rectus femoris affects balance recovery in children with CP.
Background: Surveillance scans performed after autologous stem cell transplant (auto-HCT) for patients with Hodgkin disease (HD) have no proven survival benefit. Methods: We studied survival differences among patients with HD after auto-HCT whose recurrences were detected on clinical history and exam, versus those detected on routine surveillance scan. Results: Among the 98 patients with HD that underwent auto-HCT from 2000 to 2014 at our institution, 30 relapsed, of which 21 were detected radiologically and 9 clinically. There were no statistically significant differences in patient characteristics between the 2 groups. The median time to progression was 118 days for the clinical cohort and 284 days for the radiological cohort (p = 0.05). Median overall survival (OS) was 728 days for the clinical cohort, and was not reached for the radiological cohort (p = 0.02). Discussion: In our review, most patients with HD after auto-HCT were diagnosed radiologically. Patients whose relapse was diagnosed clinically were likely to be detected earlier and have a shorter OS. Patients with aggressive disease may be detected when clinically relevant, regardless of scanning. Routine scanning may not be necessary in the majority of patients with HD following auto-HCT.
e19001 Background: Surveillance scans performed after autologous stem cell transplant (AutoSCT) for patients with relapsed/refractory (RR) diffuse large B Cell lymphoma (DLBCL) have no proven survival benefit. We studied survival differences among patients with RR DLBCL post AutoSCT whose recurrences were detected on clinical history and exam, versus those detected on routine surveillance scan. Methods: We retrospectively identified 139 patients from our institutional database with DLBCL who underwent AutoSCT from 2000 to 2014. All patients had surveillance scans performed at days 100, 180 and at 1-year post AutoSCT. Results: Among the 139 patients with RR DLBCL that underwent AutoSCT, 37 relapsed, of which 21 were clinical and 16 radiological. There were no statistically significant differences in patient characteristics, although more patients in the clinical cohort had extra-nodal and bulky disease (Table 1). The median time to progression was 167 days for the clinical cohort and 565 days for the radiological cohort (p= 0.03). Median follow-up was 587 days for the clinical cohort and 1503 days for the radiological cohort (p=0.002). Median overall survival (OS) was 587 days for the clinical cohort, and was not reached for the radiological cohort (p=0.006). Conclusions: In our review, most patients with relapsed DLBCL after AutoSCT were diagnosed clinically. Patients whose relapse was diagnosed clinically were likely to be detected earlier and have a shorter OS. Our data indicates that patients with aggressive disease may be detected when clinically relevant, regardless of scanning. Given the known risks of excess radiation exposure, our data suggests that routine scanning may not be necessary in the majority of patients with DLBCL following AutoSCT. [Table: see text]
Surveillance scans after autologous stem cell transplant (auto-HCT) for patients with relapsed/refractory (RR) diffuse large B Cell lymphoma (DLBCL) have no proven survival benefit. We studied survival differences among patients with RR DLBCL post auto-HCT whose recurrences were detected clinically versus with routine surveillance imaging. Among the 139 patients with RR DLBCL that underwent auto-HCT from 2000 to 2014 at our institution, 37 relapsed: 21 clinical and 16 radiological. The median time to progression was 167 days for the clinical cohort and 565 days for the radiological cohort (p = 0.03), and median overall survival (OS) was 587 days and not reached, respectively (p = 0.006). Most patients with relapsed DLBCL after auto-HCT were diagnosed clinically and were likely to be detected earlier and have a shorter OS. Relapse in patients with aggressive disease will likely be detected when clinically apparent, and the outcome of these patients is independent of the way the relapse is diagnosed. Thus, universal scanning after auto-HCT appears to have little benefit.
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