Monday, May 8, 2017

Short stems in reverse total shoulder arthroplasty

Short stems with metaphyseal fixation are attractive to surgeons as they provide the option of easier revision or extraction if necessary. In addition, the "curved" and not straight humeral endosteal canal is reamed asymmetrically when conventional stems are used which creates a stress riser at the tip of the long stems. Undersizing the stem distally is an option to avoid this problem. Regardless of the approach used, the modulus of elasticity of the bone is different compared to metal and the risk of peri-prosthetic fracture cannot be eliminated. Below is an example of short stem - press fit used in reverse total shoulder arthroplasty which may provide the benefit of minimizing asymmetric reaming at the tip of the stem.