Triangular Osteosynthesis as a Treatment of Lumbopelvic Dissociation with Acute Cauda Equina Syndrome in an 11-Year-Old Patient.

This case offers a safe and effective method for treating lumbopelvic dissociation in a pediatric patient with cauda equina syndrome using a triangular osteosynthesis construct. After a high-speed accident, an 11-year-old girl was admitted to the hospital with bowel and bladder incontinence and bilateral lower extremity weakness. The orthopaedic trauma and spine teams elected for surgical treatment with a triangular osteosynthesis construct, a procedure usually reserved for adults. The surgery was uncomplicated, and the patient experienced complete resolution of her preoperative symptoms. She is doing well over 1-year postoperatively, with full neurologic recovery, maintained reduction, bony healing, and subsequent implant removal. To our knowledge, this is the youngest reported case of lumbopelvic dissociation treated in this manner and represents a viable treatment option.

Complications following posterior spinal fusion for adolescent idiopathic scoliosis: a retrospective cohort study using the modified Clavien-Dindo-Sink system.

PURPOSE: Published complication rates after posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS) range from 1 to 22%. Complications are often minor and may be underestimated in registries. This study describes complications of PSF for AIS, classifies them according to a Clavien-Dindo-Sink (CDS) system, and investigates risk factors for occurrence of a complication. METHODS: This retrospective cohort study at two academic centers included all AIS patients aged 10-18 who underwent primary PSF 4/2014-12/2019. Data included demographics, comorbidities, curve magnitude, Lenke classification, levels osteotomized/fused, implant density, 90-day emergency department visits, readmissions, reoperations, and complications as defined by Harms Study Group. RESULTS: Among 424 patients, mean age was 14.7, mean BMI 22, 77% were female, and 57% had no comorbidities. There were 270 complications (0.64 per patient); 198 patients (47%) had ≥ 1 complication; and 63 patients (15%) had CDS grade ≥ II complications (deviation from standard postoperative course). Complications not related to persistent pain occurred in 103 patients (24%). Ninety-three percent of complications did not require readmission or reoperation (CDS I-II). Within 90 days, 8% presented to an ED, 2% required readmission, and 2% required reoperation. Common complications were back pain > 6 weeks postoperatively (26%), surgical site complications (7%), and ileus/prolonged constipation (3%). Risk factors for experiencing any complication were BMI ≥ 34 (OR 3.44) and Lenke 6 curve (OR 1.95). CONCLUSION: One in four AIS patients experiences a complication not related to persistent pain after primary PSF, higher than rates published from self-reported registries. Obesity and Lenke 6 curve may increase risk. While most do not require readmission or surgery, 15% of patients have their postoperative course altered by complications. LEVEL OF EVIDENCE: III-retrospective cohort study.

ALK Fusion Partners Impact Response to ALK Inhibition: Differential Effects on Sensitivity, Cellular Phenotypes, and Biochemical Properties.

Oncogenic tyrosine kinase fusions involving the anaplastic lymphoma kinase (ALK) are detected in numerous tumor types. Although more than 30 distinct 5' fusion partner genes have been reported, treatment of ALK-rearranged cancers is decided without regard to which 5' partner is present. There is little data addressing how the 5' partner affects the biology of the fusion or responsiveness to ALK tyrosine kinase inhibitors (TKI). On the basis of the hypothesis that the 5' partner influences the intrinsic properties of the fusion protein, cellular functions that impact oncogenic potential, and sensitivity to ALK TKIs, clonal 3T3 cell lines stably expressing seven different ALK fusion variants were generated. Biochemical and cellular assays were used to assess the efficacy of various ALK TKIs in clinical use, transformative phenotypes, and biochemical properties of each fusion. All seven ALK fusions induced focus formation and colonies in soft agar, albeit to varying degrees. IC50s were calculated for different ALK TKIs (crizotinib, ensartinib, alectinib, lorlatinib) and consistent differences (5-10 fold) in drug sensitivity were noted across the seven ALK fusions tested. Finally, biochemical analyses revealed negative correlations between kinase activity and protein stability. These results demonstrate that the 5' fusion partner plays an important biological role that affects sensitivity to ALK TKIs.Implications: This study shows that the 5' ALK fusion partner influences ALK TKI drug sensitivity. As many other kinase fusions are found in numerous cancers, often with overlapping fusion partners, these studies have ramifications for other kinase-driven malignancies. Mol Cancer Res; 16(11); 1724-36. ©2018 AACR.