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Hook plate fixation employing a polyaxial angular stable plate finally restores the coracoclavicular distance more accurately than augmentation with a PDS sling. Although in HP group no implant failure occurred, major disadvantages are initial overcorrection and acromial osteolysis. Both have no influence on final functional results.

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We investigate experimentally a Josephson vortex ratchet -a fluxon in an asymmetric periodic potential driven by a deterministic force with zero time average. The highly asymmetric periodic potential is created in an underdamped annular long Josephson junction by means of a current injector providing efficiency of the device up to 91%. We measured the ratchet effect for driving forces with different spectral content. For monochromatic high-frequency drive the rectified voltage becomes quantized. At high driving frequencies we also observe chaos, sub-harmonic dynamics and voltage reversal due to the inertial mass of a fluxon. The ratchet effect, i.e., the net unidirectional motion of a particle in a spatially asymmetric periodic potential in the presence of deterministic or stochastic forces with zero time average, received a lot of attention during the 20-th century. The second law of thermodynamics does not allow to extract useful work out of equilibrium thermal fluctuations, as was didactically demonstrated by Feynman [1]. Thus, the only way to produce useful work is to supply non-native fluctuations (usually colored noise), which is the basic principle of operation for any ratchet.Particularly during the last decade ratchets were receiving a lot of attention [2,3,4]. Several new implementations, in particular based on the motion of the Josephson phase in SQUIDs [5] or vortices in long Josephson junctions (LJJ) [6,7,8,9] or Josephson junction arrays (JJA) [10,11,12], were suggested and tested. The investigation of quantum ratchets [13,14,15], i.e., a quantum particle moving/tunneling quantum mechanically in an asymmetric potential, is a fascinating new field not very well developed up to now especially experimentally. Advantages of Josephson junction based ratchets are: (I) directed motion results in an average dc voltage which is easily detected experimentally; (II) Josephson junctions are very fast devices which can operate (capture and rectify noise) in a broad frequency range from dc to ∼ 100 GHz, thus capturing a lot of spectral energy; (III) by varying junction design and bath temperature both overdamped and underdamped regimes are accessible; and (IV) one can operate Josephson ratchets in the quantum regime [15].In this letter we investigate experimentally the deterministic underdamped Josephson vortex ratchet (JVR), in which a Josephson vortex (fluxon) moves along a LJJ. We implemented a novel, effective way to construct a strongly asymmetric potential by means of a current injector and systematically study a quasi-statically driven ratchet with different spectral content of the driver. For non-adiabatic drive we observe quantized rectification, voltage reversal, sub-harmonic, and chaotic dynamics. Our system can be described by the following perturbed sine-Gordon equation [6] φwhere φ is the Josephson phase, the curvilinear coordinate x along the LJJ and the time t are normalized to the Josephson penetration depth λ J and inverse plasma frequency ω −1 p , accordingly, α is the dimensionless damping pa...

Charcot neuroosteoarthropathy of the feet can induce severe instability and deformity with subsequent plantar ulceration leading to substantial disability or even amputation. Traditionally, nonoperative treatment is regarded as the primary option of treatment while surgery is restricted to treating complications or failure of nonoperative treatment. Failed nonoperative treatment essentially prolongs treatment period. We retrospectively reviewed 22 patients (26 feet) with midfoot (n = 9) or hindfoot (n = 17) neuropathy who underwent primary surgical reconstruction and reorientation arthrodesis due to manifest instability, nonplantigrade foot position, and deformity with overt (n = 8) or what we judged was impending ulceration (n = 9). The minimum followup was 0.5 years (mean, 2.7 years; range 0.5-7 years). All eight ulcers healed without recurrence of ulceration or manifestation of new ulcers during the followup period. We observed complications leading to further surgery in nine patients: five with perioperative hematoma and four with instability.