Total Ankle Arthroplasty for Posttraumatic Fracture Versus Primary Osteoarthritis: An Analysis of Complications, Revisions, and Prosthesis Survival.

BACKGROUND: Most outcome studies of total ankle arthroplasty (TAA) do not discriminate by arthritis etiology. The primary purpose of this study was to compare the complications of TAA between posttraumatic fracture osteoarthritis (fracture PTOA) and primary osteoarthritis (POA). METHODS: Ninety-nine patients who underwent TAA were retrospectively evaluated with a mean follow-up of 3.2 years (range 2 to 7.6 years). 44 patients (44%) had a diagnosis of POA while 55 patients (56%) had a diagnosis of fracture PTOA (40 malleolar fractures [73%], 14 pilon fractures[26%], and 1 talar fracture [1%]). Patient demographics, preoperative coronal plane alignment, postoperative complications, and revision surgery data were collected. Categorical variables were compared with chi square and Fisher exact tests and means with the Student t -test. Survival was assessed with Kaplan-Meier and log-rank analyses. RESULTS: A higher overall complication rate was associated with fracture PTOA (53%) compared with POA (30%) ( P = 0.04). No difference was observed in rates of any specific complication by etiology. Survival, defined as revision surgery with TAA prosthesis retention, was comparable between POA (91%) and fracture PTOA (87%) ( P = 0.54). When defined as failure requiring prosthesis explant, POA demonstrated significantly greater survival (100%) as compared with fracture PTOA (89%) ( P = 0.03). A higher rate of talar implant subsidence and loosening was noted in TAA with prior pilon (29%) as compared to malleolar fractures (8%) that was not statistically significant ( P = 0.07). Fracture PTOA was associated with preoperative valgus deformity ( P = 0.04). Compared with varus and normal alignment, preoperative valgus deformity was associated with the need for any revision surgery ( P = 0.01) and prosthesis explant ( P = 0.02). CONCLUSIONS: Compared with POA, fracture PTOA was associated with a markedly higher complication rate after TAA and was at higher risk of failure requiring prosthesis explant. Fracture PTOA was markedly associated with preoperative valgus malalignment, an identified risk factor in this series for revision surgery and prosthesis explant. Pilon fractures may represent a group at risk of complications related to talar implant subsidence and loosening compared with malleolar fractures and thus warrants additional investigation. LEVEL OF EVIDENCE: III.

Patellofemoral Joint Auto-fusion after Patella Tendon Repair: A Case Report.

INTRODUCTION: Post-traumatic patellofemoral auto fusion is poorly described in the literature and its etiology may be multifactorial. Management options are not well published and this case report addresses a rare and complex case of patellofemoral autofusion after a patellar tendon repair with a description of our surgical approach and ultimately improvement in patient outcome and satisfaction. CASE PRESENTATION: A 59-year-old African American female suffered an acute traumatic patellar tendon rupture that was treated with a primary repair that resulted in sequelae leading to a subsequent open procedure revealing an osseous bridge between the patella and trochlea. After osteotomy of this bridge, the patient's range of motion improved. CONCLUSION: For the appropriate management of arthrofibrosis surgeons should focus on modifiable risk factors including close follow-up with patients, patient expectation management, and consider surgical intervention such as techniques described below in recalcitrant cases to evaluate for post-traumatic sequelae including bone bridge formation.

Magnetic signatures of 120 K superconductivity at interfaces in La2CuO4+δ.

In self-assembled vertically aligned nanocomposite (VAN) thin films of La2CuO4+δ + LaCuO3, we find from DC magnetic susceptibility measurements, weak signatures of superconductivity at ∼120 K. This compares to a maximum TC of 40 K in bulk La2CuO4+δ. The 120 K signature occurs only when both c-axis and a-axis oriented La2CuO4+δ grains are present in the films. The superconductivity was lost after 3 months of storage but was recovered by annealing in oxygen. From lattice parameter analyses undertaken close to the c/a grain boundaries, it was determined that expansion of the La perovskite block in c-La2CuO4+δ enables the differently oriented grains to join at the interface. This expansion is consistent with the higher TC interfacial region. The work shows a new direction for increasing TC in cuprates - namely careful strain engineering of the crystal structure independently in-plane and out-of-plane.

3D strain-induced superconductivity in La2CuO4+δ using a simple vertically aligned nanocomposite approach.

A long-term goal for superconductors is to increase the superconducting transition temperature, T C. In cuprates, T C depends strongly on the out-of-plane Cu-apical oxygen distance and the in-plane Cu-O distance, but there has been little attention paid to tuning them independently. Here, in simply grown, self-assembled, vertically aligned nanocomposite thin films of La2CuO4+δ + LaCuO3, by strongly increasing out-of-plane distances without reducing in-plane distances (three-dimensional strain engineering), we achieve superconductivity up to 50 K in the vertical interface regions, spaced ~50 nm apart. No additional process to supply excess oxygen, e.g., by ozone or high-pressure oxygen annealing, was required, as is normally the case for plain La2CuO4+δ films. Our proof-of-concept work represents an entirely new approach to increasing T C in cuprates or other superconductors.

Towards large scale preparation of graphene in molten salts and its use in the fabrication of highly toughened alumina ceramics.

Highly crystalline graphene nanosheets were reproducibly generated by the electrochemical exfoliation of graphite electrodes in molten LiCl containing protons. The graphene product has been successfully applied in several applications. This paper discusses the effect of molten salt produced graphene on the microstructures and mechanical properties of alumina articles produced by slip casting and pressureless sintering, which is one of the most convenient methods for the commercial production of alumina ceramics. In addition to graphene, graphite powder and multi-walled carbon nanotubes (CNTs) were also used to prepare alumina articles for comparative purposes. A graphene strengthening effect was realized through microstructural refinement and by influencing the formation of alumina nanorods during the sintering of α-Al2O3 articles. The fracture toughness of the sintered alumina articles increased to an impressive value of 6.98 MPa m(1/2) by adding 0.5 wt% graphene nanosheets. This was attributed to the unique microstructure obtained, comprised of micrometer sized alumina grains separated by alumina nanorods.