This narrative review traces 80 years of shoulder arthroplasty, from Pean's 1893 prosthesis to modern designs. It follows the arc from Neer's hemiarthroplasty and anatomic total shoulder arthroplasty through the Grammont reverse and today's implant modifications. It frames how each design change tried to solve a specific failure mode.
The through-line of shoulder arthroplasty history is a series of trade-offs, and knowing why each design exists lets you reason about implant selection. Constrained designs failed because rigid coupling dumped force on the glenoid. Neer's unconstrained aTSA fixed that by letting soft tissue stabilize, which is why anatomic replacement requires a functional rotator cuff.
Grammont's key insight is high-yield: medializing and distalizing the center of rotation powers the deltoid, making reverse arthroplasty the answer when the cuff is gone.
Every modern modification is a trade-off you should recognize. Lateralization buys external rotation and less notching at the cost of glenoid loosening. Lower neck-shaft-angle reduces notching. Inlay favors notching, onlay favors spine fractures. Remember the numerical thresholds: baseplate needs 50% contact and under 10° version, and aTSA fails more when glenoid retroversion exceeds 15°.
This narrative review traces 80 years of shoulder arthroplasty, from Pean's 1893 prosthesis to modern designs. It follows the arc from Neer's hemiarthroplasty and anatomic total shoulder arthroplasty through the Grammont reverse and today's implant modifications. It frames how each design change tried to solve a specific failure mode.
The through-line of shoulder arthroplasty history is a series of trade-offs, and knowing why each design exists lets you reason about implant selection. Constrained designs failed because rigid coupling dumped force on the glenoid. Neer's unconstrained aTSA fixed that by letting soft tissue stabilize, which is why anatomic replacement requires a functional rotator cuff.
Grammont's key insight is high-yield: medializing and distalizing the center of rotation powers the deltoid, making reverse arthroplasty the answer when the cuff is gone.
Every modern modification is a trade-off you should recognize. Lateralization buys external rotation and less notching at the cost of glenoid loosening. Lower neck-shaft-angle reduces notching. Inlay favors notching, onlay favors spine fractures. Remember the numerical thresholds: baseplate needs 50% contact and under 10° version, and aTSA fails more when glenoid retroversion exceeds 15°.