In some embodiments, connecting element 12 can be made of metal such as Nickel-Titanium alloy, stainless steel, titanium, cobalt-based alloy, or using tantalum, Gold, Platinum or Platinum-Iridium for enhance radio-opacity, or a polymer including a shape memory polymer with or without the addition of radio-opaque material e.g. barium sulfate, and/or composed of any known and/or convenient material