Apparatus and methods for bone repair preparation
Apparatus and methods for preparing a fractured bone for repair. Preparing the bone may include fracture reduction. Preparing the bone may include holding a fracture in reduction. Preparing the bone may include identifying locations for obtaining access to an interior region of the bone. The apparatus may include structures outside the bone that interact with fragments of the bone. The structures may participate in the reduction. The structures may participate in holding the reduction. The structures may participate in identifying the locations.
1. Apparatus for positioning a surgical tool relative to a site interior to a fractured bone, the apparatus comprising:
a pin configured to penetrate a fragment of the bone; and
a support that is configured to articulate relative to a longitudinal axis of the pin and indicate an access point that lies in a plane that is transverse to the longitudinal axis and corresponds to the site.
2. The apparatus of claim 1 wherein the support includes:
a concave surface for articulating against the pin; and
an indicator for indicating the access point.
3. The apparatus of claim 2 wherein the support further includes a cannulated fixture that is configured to receive the pin, the cannulated fixture including the concave surface.
4. The apparatus of claim 1 wherein the support is configured to span from a first anatomical aspect of the bone to a second anatomical aspect of the bone.
5. The apparatus of claim 4 wherein:
the bone is a radius;
the first anatomical aspect is a dorsal aspect; and
the second anatomical aspect is an anterior aspect.
6. The apparatus of claim 1 wherein, when the bone fragment is a first bone fragment, the pin is fixed to a jig that retains the first bone fragment in a reduced orientation relative to a second bone fragment.
7. The apparatus of claim 1 wherein:
the pin and the support, when mutually engaged, define a spherical surface, the pin lying along a radius of the spherical surface; and
the support is configured such that the access point is located at an intersection of the spherical surface and soft tissue adjacent the bone.
8. The apparatus of claim 7 wherein the pin includes a detent that defines a maximum penetration depth of the pin into the bone fragment.
9. The apparatus of claim 8 further comprising, when the detent is first detent, a second detent that defines a minimum elevation, relative to the bone fragment, of the support when the support and the pin are engaged.
10. The apparatus of claim 7 wherein the pin includes a detent that defines a minimum elevation, relative to the bone fragment, of the support when the support and the pin are engaged.
11. The apparatus of claim 1 wherein the support comprises:
a fixture that is configured to engage the pin; and
an extension that is configured to extend, away from the fixture, along a spherical trajectory, until it contacts soft tissue adjacent the bone.
12. The apparatus of claim 11 wherein the extension comprises an indicator that indicates the access point when the indicator is proximate the bone.
13. The apparatus of claim 12 wherein the indicator extends away from the extension in a direction that is orthogonal to the spherical trajectory.
14. The apparatus of claim 1 further comprising an elongated guide having an end and a guide surface, the guide being in mechanical coordination with the support such that the guide end corresponds to the access point and the guide surface is oriented to align a surgical tool with the site.
15. The apparatus of claim 14 wherein:
the pin has a penetrating end that is configured to be placed in the bone fragment; and
the support is configured to orient the guide such that the guide surface is oriented to align the surgical tool with the penetrating end.
16. The apparatus of claim 1 further comprising:
a first radiopaque target on a first target arm;
a second radiopaque target on a second target arm;
wherein:
the site and the access point define a guide axis;
the first target arm is in mechanical communication with the pin;
the second target arm is in mechanical communication with the pin;
the first target arm is configured to support the first target at a first distance along a first direction away from the guide axis; and
the second target arm is configured to support the second target at a second distance along a second direction away from the guide axis, the second direction being substantially perpendicular to the first direction.
17. The apparatus of claim 16 wherein the first direction and the second direction define a plane that intersects the site.