Patent ID: 8388663

Claim:
A dynamic subsidence device comprising: a first member having a ramp portion; a second member contacting the first member and having an interference portion, the first and second members being moveable with respect to one another; a bearing member situated between the ramp portion of the first member and the interference portion of the second member, wherein the bearing member is freely seated between the ramp portion and interference portion when the first member is moving with respect to the second member in a first direction and wherein the bearing member directly contacts both the ramp and interference portions and is locked therebetween to prevent movement of the first member with respect to the second member in a second direction; and an access hole associated with at least one of the first and second members to permit access of an instrument therethrough such that when the bearing member is locked between the ramp and interference portions, the instrument may dislodge the bearing member and push the bearing member up the ramp portion to allow movement of the first and second members in the first direction, wherein the first member further includes a first prong and a second prong, the first prong of the first member having a male portion and a receiving portion, the second prong of the first member including the ramp portion, and wherein the second member further includes a first prong and a second prong, the first prong of the second member having a female portion configured to receive the male portion of the first prong of the first member and a guidance portion configured to engage the receiving portion of the first prong of the first member, the second prong of the second member including the interference portion.