System and method for altering rotational alignment of bone sections
A rotational correction system includes an implant having first and second sections, the implant having a rotatable permanent magnet disposed in a housing of the first section, the rotatable permanent magnet mechanically connected to a nut operatively coupled to the second section. A keyed portion is interposed between the nut and one or more non-linear grooves disposed on an inner surface of the housing. An external adjustment device having at least one rotatable magnet configured to rotate the rotatable permanent magnet of the implant is part of the system. Rotation of the rotatable permanent magnet of the implant in a first direction effectuates a clockwise change in the rotational orientation of the first section relative to the second section and rotation of the rotatable permanent magnet of the implant in a second direction effectuates a counter-clockwise change in the rotational orientation of the first section relative to the second section.
1. An intramedullary rotational correction device comprising:
a first portion configured to be secured to a first section of bone, the first portion including a non-linear groove on an inner surface thereof;
a second portion configured to be secured to a second section of bone;
an actuator disposed within the first portion; and
a rotary nut positioned between the actuator and the second portion, the rotary nut having one or more non-linear spline configured to communicate with the non-linear groove of the first portion,
wherein, upon a rotation of the rotary nut by the actuator, the one or more non-linear spline of the rotary nut is configured to communicate with the non-linear groove of the first portion thereby causing the second portion to rotate relative to the first portion.
2. The intramedullary rotational correction device of claim 1 , wherein the actuator is configured to rotate the second portion relative to the first portion upon being activated by an external adjustment device.
3. The intramedullary rotational correction device of claim 1 , wherein the actuator comprises a rotatable permanent magnet.
4. The intramedullary rotational correction device of claim 3 , wherein an external rotating magnetic field causes the rotatable permanent magnet to rotate and thereby effectuate a change in rotational orientation of the second portion relative to the first portion.
5. The intramedullary rotational correction device of claim 3 , further comprising:
a lead screw coupled to the rotatable permanent magnet such that the lead screw rotates upon rotation of the rotatable permanent magnet; and
a slip clutch disposed between the rotatable permanent magnet and the lead screw, the slip clutch configured to prevent binding of the rotatable permanent magnet and the lead screw.
6. The intramedullary rotational correction device of claim 1 , wherein the one or more non-linear spline disposed on the rotary nut and the non-linear groove of the first portion form a helical arrangement.
7. The intramedullary rotational correction device of claim 1 , further comprising:
one or more ball bearings disposed between the one or more non-linear spline on the rotary nut and the non-linear groove of the first portion.
8. The intramedullary rotational correction device of claim 7 , further comprising:
a plurality of circular pockets disposed on the one or more spline of the rotary nut and the non-linear groove of the first portion, the plurality of circular pockets configured to retain the one or more ball bearings therein disposed between the one or more non-linear spline and the non-linear groove.
9. An intramedullary rotational correction device comprising:
a first portion configured to be secured to a first section of bone;
a second portion configured to be secured to a second section of bone;
an actuator disposed within the first portion; and
a lead screw operatively connected to the actuator; and
a rotary nut positioned between the actuator and the second portion, the rotary nut having one or more non-linear spline configured to communicate with a non-linear groove of the first portion,
wherein, upon a rotation of the rotary nut by the actuator, the one or more non-linear spline of the rotary nut is configured to communicate with the non-linear groove of the first portion thereby causing the second portion to rotate relative to the first portion.
10. The intramedullary rotational correction device of claim 9 , wherein the actuator is configured to rotate the second portion relative to the first portion upon being activated by an external adjustment device.
11. The intramedullary rotational correction device of claim 9 , wherein the actuator comprises a rotatable permanent magnet.
12. The intramedullary rotational correction device of claim 11 , wherein an external rotating magnetic field causes the rotatable permanent magnet to rotate and thereby effectuate a change in rotational orientation of the second portion relative to the first portion.
13. The intramedullary rotational correction device of claim 11 , further comprising:
a slip clutch disposed between the rotatable permanent magnet and the lead screw, the slip clutch configured to prevent binding of the rotatable permanent magnet and the lead screw.
14. The intramedullary rotational correction device of claim 9 , wherein the one or more non-linear spline disposed on the rotary nut and the non-linear groove of the first portion form a helical arrangement.
15. The intramedullary rotational correction device of claim 9 , further comprising:
one or more ball bearings disposed between the one or more non-linear splines disposed on the rotary nut and the non-linear groove of the first portion.
16. The intramedullary rotational correction device of claim 15 , further comprising:
a plurality of circular pockets disposed on the one or more non-linear spline of the rotary nut and the non-linear groove of the first portion, the plurality of circular pockets configured to retain the one or more ball bearings therein disposed between the one or more non-linear spline and the non-linear groove.
17. An intramedullary rotational correction device comprising:
a first portion configured to be secured to a first section of bone;
a second portion configured to be secured to a second section of bone;
a rotatable permanent magnet disposed within the first portion; and
a lead screw operatively connected to the rotatable permanent magnet and a rotary nut positioned between the rotatable permanent magnet and the second portion, the rotary nut having one or more non-linear spline configured to communicate with a non-linear groove of the first portion,
wherein, upon a rotation of the rotary nut by the rotatable permanent magnet, the one or more non-linear spline of the rotary nut is configured to communicate with the non-linear groove of the first portion thereby causing the second portion to rotate relative to the first portion.
18. The intramedullary rotational correction device of claim 17 , wherein the rotatable permanent magnet is configured to rotate the second portion relative to the first portion upon being activated by an external adjustment device.
19. The intramedullary rotational correction device of claim 17 , wherein an external rotating magnetic field causes the rotatable permanent magnet to rotate and thereby effectuate a change in rotational orientation of the second portion relative to the first portion.
20. The intramedullary rotational correction device of claim 17 , wherein a slip clutch is located between the rotatable permanent magnet and the lead screw and configured to prevent binding of the rotatable permanent magnet and the lead screw.