Expandable rod system to treat scoliosis and method of using the same
View Patent ↗Correction of a scoliotic curve in a spine comprises the steps of implanting an expanding rod isolated completely under the skin and attached to selected portions of the scoliotic curve of the spine at opposing ends of the rod; and producing a controlled force by means of expansion of the rod over at an extended time period under external control until a desire spinal curve is obtained. An incremental force is generated to stretch the scoliotic curve of the spine between the selected portions where attachment of the rod is defined. The controlled force is provided steadily for at least one month or alternatively 1-3 months. Multiple rods may be employed each associated with a different scoliotic curve of the spine or a different portion of the scoliotic curve.
1. An apparatus for correction of a scoliotic curve in a spine comprising:
an expanding rod isolated completely under the skin, the expanding rod comprising:
a first end configured to be coupled to a first location on a subject's spine;
a second end configured to be coupled to a second location on the subject's spine, wherein the first location and second location are separated by a first length;
a hollow outer member;
an inner member configured to be telescopically slideable within the hollow member;
wherein the hollow outer member and the inner member form telescopically coupled sleeves having a first longitudinal length;
wherein the telescopically coupled sleeves are configured to be expanded by a controlled force, over an extended time period, and under external control;
Wherein the external control expands the telescopically coupled sleeves from the first longitudinal length which corresponds to the first length, to a second longitudinal length corresponding to a second length which extends along a desired spinal curve; and wherein the controlled force is generated by an incremental force to stretch the scoliotic curve of the spine, and wherein the expanding rod comprises a flexibility and is curved in a direction substantially aligned with the spine at the end and the second end where attachment of the rod is defined.
2. The apparatus of claim 1 where the controlled force is configured to be generated by expansion of the rod over an extended time period for producing the controlled force at a predetermined low level over time without any combination with fusion of vertebrae.
3. The apparatus of claim 1 where the controlled force comprises a steady force for at least one month.
4. The apparatus of claim 1 where the controlled force comprises a steady force for 1-3 months.
5. The apparatus of claim 1 where the spine has a ligamentum flavum and where the controlled force is for such period of time as is sufficient to stretch the ligamentum flavum of the spine enough to allow the spine to straighten.
6. The apparatus of claim 1 further comprising a kit of a plurality of expanding rods, each expanding rod being associated to a different scoliotic curve of the spine or a different portion of the scoliotic curve of the spine and separately producing a controlled force by expansion of each corresponding rod over a corresponding extended time period.
7. The apparatus of claim 1 where the controlled force is configured to be produced by a ratcheted longitudinal extension of the rod powered by an energy source.