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Background: Patellar tendon ruptures are uncommon, severe, and are complex cases that require early surgical intervention. Loss of function of the extensor mechanism of the knee joint might cause severe disability and inability to hold a standing position. Case Presentation: A 34-year-old Saudi male, known to have morbid obesity (class 1), came to the emergency room complaining of severe pain in the left knee after experiencing a fall on a flexed knee while playing soccer. The patient had no other significant past medical history. In this case, the injury occurred due to a minor sports accident, and there were no predisposing factors. Thus, it was decided to do patellar tendon augmented reconstruction using a pedicled hamstring tendon, involving primary repair. After the surgery, a cast was applied on the patient's knee and retained for 3 weeks, allowing only active knee flexion and passive extension. Then, active assisted knee extension was allowed through physiotherapy for 2 months, until 75%-80% of active extension was achieved. Patient was moved to out-patient department after 3 months for further assessment. Conclusion: Patellar tendon ruptures from the tibial tuberosity are quite uncommon. When the patient has morbid obesity, acute repair of the patellar tendon through reconstruction using hamstring tendons could give a positive result with good outcome in the joint's movement.

Conoscopy is the visualisation of the birefringence of materials using depolarisation of light passing through with a broad range of incident orientations. In recent years, conoscopy has become an important optical tool in the science of soft materials, such as liquid crystals and polymers, and is widely applied in materials engineering and development, for example in technologies ranging from display optics to plastic food packaging. This paper reports ‘fisheye lens conoscopy’, a fundamentally new and broadly applicable optical approach to conoscopy that is particularly appropriate for the study of soft materials. These capabilities are illustrated using a fisheye lens system to characterise birefringent and polarising polymer films and liquid crystal test cells. In addition to birefringence measurement, fisheye conoscopic determination of the emission characteristics of commercial light emitting devices such as liquid crystal displays and the transmission of topographically patterned light control films...

We describe a prototype element for use in probing electro-optic retro-reflection in sensor applications, illuminating a planar-aligned nematic liquid crystal electro-optic cell with convergent light having a single, tunable angle of incidence (tunable conical illumination). This illumination is generated using a 100X, high numerical aperture, long working-distance microscope objective under conditions of extreme spherical aberration. The electro-optic effect observed is multiple-beam optical interference between polarized reflections from the two bounding plates of the cell, rendered tunable with voltage-controlled refractive index changes induced by molecular reorientation of the liquid crystal. Characterization of the reflectivity vs. angle of incidence and applied voltage enables identification of conditions of high-contrast, low power, electro-optic reflectivity control applicable to fiber optics.