ABSTRACT
CASE PRESENTATION: An otherwise healthy, 12-year-old male presented to the emergency department after a fall down the stairs in which he landed on his right hand. Radiographs demonstrated a Salter-Harris II fracture at the base of the proximal phalanx of the fifth digit with ulnar deviation, also known as an "extra-octave" fracture. Orthopedic surgery was consulted and the fracture was reduced and placed in a short-arm cast. The patient was discharged and scheduled for orthopedic follow-up. DISCUSSION: A Salter-Harris II fracture at the base of the proximal phalanx of the fifth digit with ulnar deviation is referred to as an "extra-octave" fracture due to the advantage a pianist would gain in reach of their fifth phalanx if not reduced. However, reduction is needed if the fracture is displaced and can be achieved by several described methods including the "90-90" or "pencil" methods followed by cast or splint application. Percutaneous pinning is rarely needed. Complications include flexor tendon entrapment, collateral ligament disruption, and malunion leading to a "pseudo-claw" deformity. We recommend that all extra-octave fractures receive orthopedic follow-up in one to two weeks or sooner if severely displaced.
ABSTRACT
The design, fabrication, and transmission measurements of a photonic crystal slab edge directional coupler (PCDC) for submicron deflection sensing is presented. The dielectric modes between two structurally isolated photonic crystal edges allows for a directional coupler to be formed with low insertion loss and reduced coupling distances. The output transmission from the coupler can be related to the distance between neighbouring PC edges, thereby allowing it to be used as an intensity-based optomechanical sensor. PCDC sensors were fabricated by selectively etching the buried oxide (BOX) of surface micromachined silicon-on-insulator wafer. Based on transmission measurements, the sensitivity to horizontal separation between the edges of a fabricated PCDC of length 24.3 µm was evaluated to be 1.6 %/nm at 1495 nm. The transmission sensitivity to vertical separation between the PCDC edges of length 12.6 µm was calculated to be 0.25 %/nm, when the PCDC edges were initially displaced vertically by a distance of 300 nm. The PCDC sensors demonstrated here are compatible with broadband sources and do not depend on BOX thickness, reducing the probability of stiction.
