Although the optimal treatment for femur shaft fracture is intramedullary nailing fixation, nonunion still occurs. We determined the oligotrophic nonunion rate among femur fractures managed operatively and identified risk factors for reoperation. This was a retrospective clinical study. The data of the patients between 40 and 70 years old with diaphyseal femur fracture who have received reamed and interlocked intramedullary nailing fixation in our hospital from February 2014 to April 2018 were collected. They were followed at regular intervals for at least 1 year after the operation. The primary outcome was nonunion of the fracture site that required reoperation in accordance with the radiographic union scale for tibial shaft fracture (RUST), which is a reasonable score system for lower limb diaphyseal fracture. Three of them were hypertrophic nonunion (1.9%) and the other 13 cases were oligotrophic nonunion (8.6%) at postoperative 12 months follow-up. All of the postoperative plain films showed adequate reduction quality. The three hypertrophic nonunion cases were all obese male with fracture site comminution. Fracture at the proximal third junction, hypertension (HTN) and diabetes mellitus (DM) was significantly associated with oligotrophic nonunion of the fracture site from logistic regression analysis. The mean RUST score 3 months after the operation was not significantly different between the union group and nonunion group but was significantly lower 6 months after the operation in the nonunion group. In conclusion, intramedullary nailing of the femur shaft fractures was associated with a low risk of nonunion at the 1-year follow-up in the middle age group. Those with comorbidity such as obese, HTN, and DM, with fracture site at the proximal third junction or comminution should be followed up closely and rehabilitation with cause aggressively. Radiographic scale as the RUST score at postoperative 6 months could be used to predict this complication.

Background: Purely cutaneous Rosai-Dorfman disease (RDD) is a rare histiocytic proliferative disorder limited to the skin. To date, its pathogenesis remains unclear. Owing to recent findings of specific mutations in the mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathway in histiocytic proliferative disorders, it provides a novel perspective on the pathomechanism of cutaneous RDD. We aim to investigate the genomic mutations in MAPK/ERK pathway in cutaneous RDD. Methods: We retrospectively recruited all cases of cutaneous RDD from two hospitals in Taiwan from January 2010 to March 2020 with the clinicopathologic features, immunohistochemistry, and treatment. Mutations of neuroblastoma RAS viral oncogene homolog (NRAS), Kirsten rat sarcoma 2 viral oncogene homolog (KRAS), and v-raf murine sarcoma viral oncogene homolog B1 (BRAF) in MAPK/ERK pathway were investigated by the highly sensitive polymerase chain reaction with Sanger sequencing. Results: Seven patients with cutaneous RDD were recruited with nine biopsy specimens. The median age was 46 years (range: 17–62 years). Four of seven patients (57.1%) received tumor excision, while the other three chose oral and/or topical or intralesional steroids. NRAS mutation was detected in 4 of 7 cases (4/7; 51.7%), and NRAS A146T was the most common mutant point (n = 4/7), followed by NRAS G13S (n = 2/7). There is no KRAS or BRAF mutation detected. Conclusions: We report the NRAS mutation is common in cutaneous RDD, and NRAS A146T was the most frequent mutation in this cohort. Mutations in the NRAS gene can activate the RAS/MAPK signaling and have been reported to be associated with various cancers. It indicates that NRAS mutation in MAPK/ERK pathway may involve the pathogenesis of cutaneous RDD.

No abstract

No abstract