Background. The dynamic hip screw (DHS) with the addition of an angular stable trochanter-stabilizing plate (TSP) has been considered the ideal treatment for the unstable intertrochanteric fracture type. However, there have been few comparisons between DHS+TSP augmentation with intramedullary (IM) nailing. The aim of this retrospectively registered study was to compare the clinical outcomes of patients with the unstable type of intertrochanteric fractures treated with DHS+TSP or IM nailing (proximal femoral nail antirotation (PFNA)). Methods. From June 2013 to April 2018, 358 patients with proximal femur fracture AO/OTA type 31A2 and 31A3 treated with PFNA or DHS+TSP and followed for ≥10 months postoperatively were included. The surgical-dependent outcome evaluation included the operation time, intraoperative blood loss, postoperative decrease in hemoglobin, and blood transfusion amount. Functional status was also measured. Radiographic findings and postoperative complications were recorded and analyzed. Result. The operation time was significantly shorter in the DHS+TSP group than that in the PFNA group for both A2 and A3 fractures (A2 type: 84.0 vs.96.4 min; p<0.05; A3 type: 102.4 vs.116.1 min; p<0.05). Postoperative decrease in hemoglobin was more significant in the PFNA group than that in the DHS+TSP group for both fracture types (A2 type: −1.88 vs. −1.29 (mg/dL); p<0.05; A3 type: −1.63 vs. −1.04 (mg/dL); p<0.05). However, the patients treated with DHS+TSP had significantly more residual pain than those treated with PFNA during the final follow-up (Visual Analog Scale score, A2 type: 28.4 vs.23.2; p<0.05; A3 type: 27.5 vs.23.6; p<0.05) and complained of greater implant irritation. Conclusion. We found that DHS+TSP was associated with less operation time and less postoperative decrease in hemoglobin but more residual pain and implant irritation than those of PFNA. As a treatment for unstable intertrochanteric fracture, DHS+TSP provided ideal surgical outcomes which were not inferior to the PFNA.

A novel organosoluble polynorbornene bearing a polar, pendant, ester‐bridged epoxy group [poly(oxiran‐2‐ylmethyl 2‐methylbicyclo[2.2.1]hept‐5‐ene‐2‐carboxylate) (polyOMMC)] was prepared via the living ring‐opening metathesis polymerization (ROMP) of active norbornenes with a Ru catalyst. PolyOMMC exhibited excellent solubility in a variety of solvents. The number‐average molecular weight of polyOMMC linearly increased with the [M]/[I] ratio (where [M] is the monomer concentration and [I] is the initiator concentration), and a narrow polydispersity of 1.09–1.19 was observed; this was considered a living polymerization. When ROMP of oxiran‐2‐ylmethyl 2‐methylbicyclo[2.2.1]hept‐5‐ene‐2‐carboxylate with [M]/[I] = 350 was carried out at 30 °C in CH2Cl2, the number‐average molecular weight (7.01 × 104; polydispersity index = 1.07) was close to the calculated molecular weight (7.28 × 104), and a diblock copolymer was observed after the addition of another monomer ([M]/[I] = 350) with an increase in the number‐average molecular weight (1.60 × 105; polydispersity index = 1.11), which was close to the calculated molecular weight (1.61 × 105). The modified polynorbornenes retained good solubility in methylene chloride, tetrahydrofuran, dimethyl sulfoxide, dimethylformamide, N,N‐dimethylacetamide, and N‐methyl‐2‐pyrrdione. High‐performance polynorbornenes with active epoxy groups could be designed with great potential for applications in photoresists, UV curing, and elastomers. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4428–4434, 2006

Rationale: Heterotopic ossification (HO), which is defined as the formation of new bone in tissues that do not normally ossify, is an infrequent yet debilitating complication of burns. Herein, we report three patients who suffered from elbow HO after burn injury due to a dust explosion event. This is a case report that includes the most cases involved in a single mass casualty incident in the presented literature. Patient concerns: Case 1: A 28-year-old man presented with second-to-third degree 88% total body surface area (TBSA) burns after the explosion event. He complained of decreased progressive bilateral elbow range of motion (ROM) for 1.5 months after the burn injury. Case 2: A 28-year-old woman presented with second-to-third degree 50% TBSA burns and complained of decreased progressive bilateral elbow ROM with intolerable pain on elbow extension for 1 month after the burn injury. Case 3: A 22-year-old man presented with second-to-third degree 90% TBSA burns and complained of significantly decreased left elbow ROM with intolerable pain 5 months after the burn injury. Diagnosis: The follow-up radiograph of the symptomatic elbow of these three patients revealed heterotopic ossification formation. Three-dimensional reconstruction computed tomography performed preoperatively showed that HO mainly affected the humeroulnar joint. Interventions: We treated all three patients with surgical elbow HO resection and ulnar nerve transposition, followed by immediate passive ROM exercise since postoperative day 1 and continuous physical therapy. Outcomes: In case 1, the documented ROM gain on the last follow-up (18.5 months after surgery) was 30° in the right elbow and 118° in the left elbow. In case 2, the follow-up time was 21 months and the documented ROM gain on the last follow-up was 120° in the right elbow and 90° in the left elbow. In case 3, the follow-up time was 20 months and the documented left elbow ROM gain on the last follow-up was 40°. Lessons: We discuss our experience of treating postburn HO and review the recent literature. The postburn HO treatment results of early surgical excision combined with immediate postoperative physical therapy were satisfactory.

An efficient asymmetric vinylogous aldol/lactonization cascade reaction between β,γ-unsaturated amides and trifluoromethyl ketones has been developed. With chiral cyclohexanediamine-based tertiary amine-thiourea catalyst C4, optically active trifluoromethyl dihydropyranones have been constructed...