Elongated fixation element
View Patent ↗A fixation device, having an elongated element extending along a central axis, having a total length L and including a proximal section formed of a material that is substantially non-absorbent for electromagnetic radiation within a preselected wavelength range and a distal section formed of a material that is substantially nonabsorbent for electromagnetic radiation within the preselected wavelength range in combination with a middle section axially arranged between the proximal and distal sections, the middle section formed of a material that is substantially absorbent for electromagnetic radiation in the preselected wavelength range.
1. A fixation device configured for insertion into bone, the fixation device comprising:
an elongated element extending along a central axis, having a total length L and including:
a proximal section that is solid along the central axis and is substantially non-absorbent of electromagnetic radiation within a preselected wavelength range;
a distal section formed of a material that is substantially non-absorbent of electromagnetic radiation within the preselected wavelength range, the distal section including a pointed distal tip at a distal-most point along the central axis, the pointed distal tip configured to be impacted through a cortex of the bone; and
a middle section that is solid along the central axis and is axially arranged between the proximal and distal sections so as to space and separate the proximal section from the distal section along the central axis, thereby causing the proximal section, the distal section, and the middle section to be axially aligned with one another along the central axis, the entire middle section formed of a material that is substantially absorbent of electromagnetic radiation within the preselected wavelength range,
wherein the elongated element defines a first configuration before an application of electromagnetic radiation within the preselected wavelength range and a second configuration after the application of electromagnetic radiation within the preselected wavelength range,
i)such that in the first configuration, the middle section of the elongated element is positionally fixed relative to the proximal and distal sections, and ii) such that in the second configuration, the middle section softens and melts in response to the application of the electromagnetic radiation within the preselected wavelength range.
2. The device according to claim 1 , wherein the material of the middle section comprises one of (i) a polymer containing at least partially a substance colored to absorb electromagnetic radiation within the predetermined wavelength range, (ii) a polymer including a reflecting coating, (iii) a polymer self-colored to absorb electromagnetic radiation within the predetermined wavelength range; and (iv) a polymer having a coating receiving colored substances from body fluids in contact therewith, the preselected wavelength range being selected to be absorbed by the polymer after it has received the colored substances from the bodily fluids.
3. The device according to claim 2 , wherein the material of the middle section is a thermoplastic material.
4. The device according to claim 3 , wherein the thermoplastic material is at least one of polymethylmethacrylate, poly-alpha-hydroxyester, polyorthoester, polyanhydride, polyphosphazenes, poly(propylenefumarate), polyesteramide, polyethylenefumarate, polylactide, polyglycolide, poly(lactic-co-glycolic acid), polycaprolacton, trimethylenecarbonate, polydioxanone and polyhydrobutyrate.
5. The device according to claim 1 , wherein the middle section is entirely formed of one of a polymeric and a copolymeric material.
6. The device according to claim 5 , wherein the entire device is formed of one of a polymeric and a copolymeric material.
7. The device according to claim 1 , wherein the preselected wavelength range is from 400 to 1300 nm.
8. The device according to claim 1 , wherein the middle section melts at a temperature in the range of 50° C. to 250° C.
9. The device according to claim 1 , wherein the proximal section and the distal section have a diameter D and are connected by a bridge of reduced diameter d<D around which the middle section is arranged.
10. The device according to claim 9 , wherein the ratio D/d is one of larger than 2 and larger than 3.
11. The device according to claim 9 , wherein the ratio D/d is one of smaller than 7.5 and smaller than 6.
12. The device according to claim 1 , wherein the non-absorbent material has a volume V in the range of 1 to 500 mm 3 and the absorbent material has a volume v in the range of 1 to 400 mm 3 .
13. The device according to claim 1 , wherein the distal section has an axial length of 0.06 L to 0.15 L, the middle section has an axial length of 0.50 L to 0.70 L and the proximal section has an axial length of 0.25 L to 0.35 L.
14. The device according to claim 1 , the device further comprising a suture.
15. The device according to claim 14 , wherein the distal section comprises a transverse through hole sized and shaped to receiving the suture therethrough.
16. The device according to claim 15 , wherein the transverse through hole has a hole axis arranged in a plane substantially orthogonal to the central axis.
17. The device according to claim 1 , the device further comprising a mirror arranged between the middle section and the distal section to reflect electromagnetic radiation that passes distally through the middle section proximally back into the middle section.
18. The device according to claim 1 , wherein the elongated element is one of a bone screw, bone rod, bone dowel, pin, plate, dowel, hose, tube, thread, thread in a hose or tube, a bone anchor, a dental implant and a dental root implant.
19. The fixation device of claim 1 , wherein no portion of the distal section overlaps the proximal section along a second direction perpendicular to the central axis.