Cementless reverse total shoulder

 The humeral component in reverse total shoulder is exposed to bending, torsional and inferiorly displacing loads. The component can be stabilized with cement or with a tight fitting humeral component. 

The former creates a stress riser at the distal tip and complicates potential revision

The latter can lead to the risk of fracture on insertion and stress shielding (yellow arrows). 

These undesirable features can be avoided through the use of a thinner humeral stem secured into place with impaction autograft (or allograft if autograft is not available). By filling the space between the humeral stem and the endosteal humeral cortex with compressible cancellous bone, the humeral component is well fixed and loads applied to the humeral component are distributed broadly to the humerus, avoiding the localized implant-humerus contact that leads to stress shielding.

As emphasized in Torsional stability of modular and non-modular reverse shoulder humeral components in a proximal humeral bone loss model the use of a mono block (single piece) humeral component can further increase torsional stability.

Here are a few examples of impaction autografted, mono block, thinner, standard length humeral stems showing secure fixation without stress shielding

    

The authors of Cementless Reverse Total Shoulder Arthroplasty Implantation With Humeral Matchstick Autograft Augmentation: Early Radiographic Outcomes report on the use of "match stick" humeral head autograft and a short curved stem.

This combination may make it more difficult to achieve even distribution of load and to avoid localized contact between the humeral component and the humeral cortex (red arrows).

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Here are some videos that are of shoulder interest
Shoulder arthritis - what you need to know (see this link).
How to x-ray the shoulder (see this link).
The ream and run procedure (see this link).
The total shoulder arthroplasty (see this link).
The cuff tear arthropathy arthroplasty (see this link).
The reverse total shoulder arthroplasty (see this link).
The smooth and move procedure for irreparable rotator cuff tears (see this link).
Shoulder rehabilitation exercises (see this link).