The Ascl3 transcription factor marks a subset of salivary gland duct cells present in the three major salivary glands of the mouse. In vivo, these cells generate both duct and secretory acinar cell descendants. Here, we have analyzed whether Ascl3-expressing cells retain this multipotent lineage potential in adult glands. Cells isolated from mouse salivary glands were cultured in vitro as non-adherent spheres. Lineage tracing of the Ascl3-expressing cells within the spheres demonstrates that Ascl3+ cells isolated from adult glands remain multipotent, generating both duct and acinar cell types in vitro. Furthermore, we demonstrate that the progenitor cells characterized by Keratin 5 expression are an independent population from Ascl3+ progenitor cells. We conclude that the Ascl3+ cells are intermediate lineage-restricted progenitor cells of the adult salivary glands.

Background: Lateral condyle fractures account for 15% to 20% of pediatric elbow fractures. Among numerous proposed classification systems, the Song classification appears the most comprehensive. The utility of any classification system relies on its ability to be descriptive, reproducible, and to guide prognosis/treatment. We assessed the Song classification by applying it to 736 retrospectively treated patients. Methods: A total of 736 pediatric patients with lateral condyle fractures were identified between 2007 and 2014. In total, 60 patients were selected for a radiographic interclass and intraclass correlation study. Radiographs of the patients were reviewed by 6 observers, who independently measured radiographs for displacement on radiographs and assigned a Song classification. Treatment and outcomes were then reviewed on all 736 patients and evaluated as a successful outcome when achieving a healed fracture at discharge without significant complication or necessitating a change from initial treatment modality. Results: Weighted κ values for intrarater and interrater reliability to assign Song classification indicated excellent agreement. Intraclass correlation coefficients of 6 observers measuring displacement on radiographs in millimeters indicated good to excellent agreement. In total, 106 Song 1 fracture were primarily treated by casting alone and only 5.5% required conversion to operative intervention. Overall, 139 Song 2 fractures were treated by closed treatment (n=114, 82% successful nonoperatively, 16% converted to operative management) or surgical means (n=25, 100% success) without treatment superiority (P>0.999) and both modalities had high success rates. Song 3 fractures (n=17) demonstrated a failure rate of 80% with casting (n=10) and were better managed by closed reduction and percutaneous pinning (n=7, 100% success, P=0.002). Song 4 (n=325) fractures had low success rate (34%) with casting (n=35), but achieved higher success rates (P<0.001) when managed with either closed (n=57) or open reduction (n=233) and pin fixation (89.5% and 92.7% success, respectively, P=0.401). Song 5 fractures (n=149) generally required an open reduction in our series with good success rates (91.2%). Conclusion: This study validates the Song classification with high interobserver and intraobserver reliability. The Song classification improves on existing classification systems by better distinguishing fractures at risk for failure of nonoperative treatment and guiding treatment outcomes. Level of Evidence: Level IV.

Intraoperative arthrograms are commonly used in conjunction with closed reduction and percutaneous pinning (CRPP) of pediatric lateral condyle fractures of the humerus. The authors sought to determine how arthrograms affect management of these fractures. They reviewed all lateral condyle fractures treated surgically at a pediatric level I trauma center from 2008 to 2014. They stratified patients managed with and without an arthrogram as well as by timing of arthrogram. The authors compared injury parameters, initial and postoperative fracture displacement, and complications between groups. They identified 107 patients who were taken to the operating room for attempted closed reduction, which they classified as either CRPP without arthrogram or arthrogram first and then a decision to treat open or with CRPP. Fifty-eight (54.21%) underwent CRPP without arthrogram and 49 (45.79%) underwent arthrogram. Of those who had arthrograms, 27 (25.23%) were prior to fixation and 22 (20.56%) were after fixation. There was no difference in age, weight, or preoperative displacement among the groups. Mean postoperative displacement was significantly lower in the no arthrogram group vs the arthrogram group (0.91 mm vs 1.68 mm; P <.0001), but it did not differ based on timing of arthrogram ( P =.836). Arthrograms changed management in 4 (8%) of 49 patients who had them. There was no statistical difference in the rate of changed management by timing of arthrogram (before vs after fixation, 14.8% vs 0%; P =.060). The authors demonstrated that arthrograms may be useful for assessing final fracture alignment after CRPP, but are unlikely to result in a treatment change and are not associated with improved postoperative alignment. [ Orthopedics . 2020; 43(1):30–35.]

Background: Health care in America continues to place more importance on providing value-based medicine. Medicare reimbursements are increasingly being tied to this and future policy changes are expected to reinforce these trends. Recent literature has shown pediatric femur fractures in preschool-age children have equivalent clinical and radiographic outcomes when treated with spica casting or flexible intramedullary nails (IMN). We compared hospital care statistics including charges for nonoperative versus operative treatment for closed femur fractures in 3- to 6-year-olds. Methods: An IRB-approved retrospective chart review was performed of 73 consecutive 3- to 6-year-olds treated at a regional level 1 pediatric hospital from January 1, 2009 to December 31, 2013 with an isolated, closed femoral shaft fracture. Exclusion criteria included open fractures, bilateral injury, and polytrauma. Immediate spica casting was performed in the Emergency Department or Anesthesia Procedure Unit versus IMN in the operating room. Results: A total of 41 patients were treated with spica casting and 32 patients were treated operatively with flexible IMNs; 3 patients failed nonoperative care. After analysis of final treatment groups, significant differences included age at injury: 3.7 years for cast versus 5.3 years for IMN (P<0.001), time to discharge 21 versus 41 hours (P<0.001), 3.2 versus 4.4 clinic visits (P<0.001), follow-up 3.5 versus 9.4 months (P<0.001). Orthopedic surgeon charges were $1500 for casted patients versus $5500 for IMN (P<0.001). Total hospital charges were $19,200 for cast versus $59,700 for IMN (P<0.001). No difference was found between clinic charges or number of radiographs between groups. In total, 76% of cast group were discharged <24 hours from admission versus 8.6% in operative group. In the operative group, 83% had implant removal with no statistically significant charge difference between those who had implant removal versus retention. Conclusions: Treatment of pediatric femur fractures in 3- to 6-year-olds with IMN is associated with longer hospital stays, significantly greater hospital charges, longer follow-up and more clinic visits compared with spica casting. These findings are at odds with previous literature showing shorter hospital stays and decreased cost with nailing compared to traction and casting. This shows a clear difference between 2 treatments that yield similar clinical and radiographic outcomes. Level of Evidence: Level III—retrospective comparative study.