Surgical Repair of Radial-Ulnar Fracture by Static Intramedullary Interlocking Nailing in a Crossbred Heifer.

OBJECTIVE: Study included surgical management of radius and ulna fracture in a 2-year-old, 220 kg crossbred heifer presented with a 2-day-old history of injury resulting in severe, non-weight bearing lameness of the left forelimb. METHODS: The condition was diagnosed clinically and confirmed radiographically as a middle third oblique comminuted fracture of the left radius and ulna. Static intramedullary interlocking nailing was performed for fracture fixation. An interlocking nail of 12-mm diameter and 26-cm length was introduced in a retrograde manner from the distal aspect of the radius. RESULTS: The animal was able to bear weight on the affected limb within 7 days post surgery. Good callus formation and complete weight bearing were observed by 35th day. Bending of the screws and osteophytic reaction were the major postoperative complications observed radiographically. CLINICAL SIGNIFICANCE: From this case study, it was established that static intramedullary interlocking nailing can be used as an alternative technique for fracture repair of the radius and ulna in cattle where stable fracture fixation by bone plating is questionable.

Large-scale topographical screen for investigation of physical neural-guidance cues.

A combinatorial approach was used to present primary neurons with a large library of topographical features in the form of micropatterned substrate for high-throughput screening of physical neural-guidance cues that can effectively promote different aspects of neuronal development, including axon and dendritic outgrowth. Notably, the neuronal-guidance capability of specific features was automatically identified using a customized image processing software, thus significantly increasing the screening throughput with minimal subjective bias. Our results indicate that the anisotropic topographies promote axonal and in some cases dendritic extension relative to the isotropic topographies, while dendritic branching showed preference to plain substrates over the microscale features. The results from this work can be readily applied towards engineering novel biomaterials with precise surface topography that can serve as guidance conduits for neuro-regenerative applications. This novel topographical screening strategy combined with the automated processing capability can also be used for high-throughput screening of chemical or genetic regulatory factors in primary neurons.