Distractor mechanism for external fixation device
US5681309A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 10, 1995 |
| Grant date | Oct 28, 1997 |
| Priority date | — |
| Expiry date | Oct 10, 2015 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B17/66
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A distraction apparatus for an external fixation device used to rigidly immobilize bone fragments during bone lengthening and angular deformity correction includes distractor mechanisms and pivotable spacers for connecting frame members of an external fixator, and wire and half pin fasteners. The interconnected distractor mechanisms, pivotable spacers and frame members form a rigid structure with rigidity which is maintained during adjustment of the distraction. For linear distraction, the distraction mechanism is a single screw assembly with a single-threaded rod and dual plastic nuts, or one of three various types of telescoping screw assemblies having a single-threaded rod, a coaxial sleeve for receiving the rod and one of three types of plastic connector assemblies. For angular distraction, the distraction mechanism includes an angular distractor with a rotatable knob and pivotable spacers which are connected to the frame members. For wire and half pin fixation to the frame members, the fastener assembly includes a metal fixation bolt with a transverse teardrop-shaped hole for providing consistent three-point contact surfaces to secure the wires and half pins regardless of thei…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.