Blade-like shaft of a hip-joint prosthesis
AssigneeSmith & Nephew Orthopaedics AG
InventorsWalter Moser, Alex Seidl, Dirk Wunderle
Life of this patent
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Abstract
Blade-like stem (10) of a hip joint prosthesis for anchoring in the femur, having a portion (19) comprising a prosthesis neck (18) on the one hand and a femur-anchoring portion (21) tapering towards a distal end (20) on the other hand, the lateral narrow side (22) of which comprises a distal straight portion (23) and a proximal arcuate portion (11), the straight portion (23) extending over a length (LD) of from 60% to 75% of the total length (LG) of the stem (10).
Claims18
1-8. (canceled)
A hip joint prosthesis stem for anchoring in the femur, wherein the stem comprises a blade-like shape and comprises:
- a prosthesis neck portion;
- and
- a femur-anchoring portion attached to the prosthesis neck portion and tapering towards a distal end, the femur-anchoring portion comprising a lateral narrow side comprising a distal straight portion extending over a length of from 60% to 75% of the total length of said stem, the lateral narrow side further comprising a proximal arcuate portion.
A hip joint prosthesis stem for anchoring in the femur, wherein the stem comprises a blade-like shape and comprises:
- a prosthesis neck portion;
- and
- a femur-anchoring portion attached to the prosthesis neck portion and tapering towards a distal end, the femur-anchoring portion comprising a lateral narrow side comprising a distal straight portion and a proximal arcuate portion, wherein said proximal arcuate portion comprises a shape corresponding to a curve defined by a proximal end of the lateral narrow side of the stem on introduction thereof into a complementary cavity in the femur while contact between a lateral-distal and proximal-medial stem contour and an associated boundary of the cavity is maintained.
A method of constructing a hip joint prosthesis with at least a proximal-lateral portion, a distal-lateral portion, and a proximal-medial portion, said method comprising:
- choosing a hip joint prosthesis shaft with a determined distal-lateral portion and proximal-medial portion;
- obtaining a curve defined by the proximal-lateral portion of the prosthesis shaft upon introduction of the shaft into a cavity in a femur such that contact between the distal-lateral and proximal-medial portions of the shaft and the associated boundary of the cavity will be maintained;
- and
- defining a proximal-lateral portion of said prosthesis shaft to generally fit said curve.
Dependencies are inferred from the claim text.