| 摘要 |
A device for connecting a longitudinal support to a bone anchor having a rounded head includes a body defining a chamber for receiving the rounded head of the bone anchor and a first channel for receiving the longitudinal support. Further, a first sleeve is slidable over the body for compressing the chamber, a second sleeve is slidable over the body for biasing the longitudinal support against the first sleeve, and a fastener is operatively associated with the body for biasing the second sleeve toward the first sleeve. The forces exerted on the second sleeve by the fastener are transferred to the first sleeve in a plane perpendicular to the central axis. Preferably, the longitudinal support contacts the first sleeve at first and second contact points or zones and one of the sleeves includes at least one extended portion for contacting the other sleeve at at least one additional contact point or zone. |
