Patent ID: 9579125
Date: 2017-02-28
CPC Classifications: A61B

Claim:
1. A bone fixation system, comprising: a bone fastener including: an outer receiver having a proximal end, a distal end and a longitudinal axis; the outer receiver including: a screw retainer sized to fit inside the outer receiver; the screw retainer including two oppositely disposed arms connected to a bone fastener receiving portion at a distal end; the screw retainer including at least one channel defined between the arms; each arm has an interlocking inner surface; the bone fastener being coupled to the screw retainer in the bone fastener receiving portion such that the bone faster is permitted to angulate in an unlocked configuration; an inner receiver sized to fit inside the outer receiver; the inner receiver including a base and two oppositely disposed arms extending upwardly from the base; the inner receiver includes at least one channel defined between the arms; each arm has an interlocking inner surface; each arm including a passageway having an opening at a proximal end of the inner receiver and extending to an opening at a distal end of the inner receiver; each passageway is sized and configured to receive an arm of the screw retainer within the passageway; the base of the inner receiver includes a lock-receiving portion having two oppositely disposed holes extending from an inside of the inner receiver outwardly into the passageways; the inner receiver being coupled to the outer receiver such that the inner receiver is movable longitudinally relative to the outer receiver; a lock located inside the lock-receiving portion of the inner receiver; the lock including a rod-receiving location having reduced entryway; the rod receiving location being sized and configured to receive a connecting rod; the lock includes two outwardly extending locking prongs having distal interlocking surfaces; the locking prongs being configured to extend into the holes in the inner receiver such that the distal interlocking surfaces of the locking prongs engage the interlocking inner surfaces of the screw retainer in a locked configuration; a set screw located between the arms of the inner receiver and having an interlocking outer surface configured to interlock with the interlocking inner surface of the arms of the inner receiver; an elongate connecting rod located between the channels of the inner receiver; wherein the bone fixation system includes an unlocked position in which the bone fastener angulates with respect to the outer receiver and the inner receiver is free to translate longitudinally with respect to the outer receiver; and a locked position in which the bone fastener and inner receiver are fixed with respect to the outer receiver.