The inlay glenoid arthroplasty in weight lifters.

Clinical and Radiographic Outcomes of Total Shoulder Arthroplasty With a Nonspherical Humeral Head and Inlay Glenoid in Elite Weight Lifters A Prospective Case Series

These authors point out that weight lifting after total shoulder arthroplasty (TSA) can place significant stresses on prosthetic glenoid implants potentially leading to instability, loosening, and wear. 

They sought to evaluate the clinical and radiographic outcomes of a TSA system with nonspherical humeral head resurfacing and an inlay glenoid in 16 weight lifters (mean ± SD age, 57.2 ± 7.8 years; 15 male) undergoing primary anatomic TSA (n . 17 shoulders, 1 staged bilateral)  for glenohumeral

osteoarthritis.  Exclusion criteria were rotator cuff deficiency, revision TSA, posttraumatic

arthritis, and inflammatory arthritis. 

Follow-up was obtained on all patients at a mean of 38 months (range, 14-63 months). All patients returned to weight lifting at 15.6 ± 6.9 weeks. Compared to the preoperative weight lifting level, at last follow-up patients reported performance at the following level: lighter weight, 1 (6%); same weight, 8 (50%); heavier weight, 7 (44%). The quantitative values for these levels are not provided.

Preoperative eccentric posterior glenoid wear was common (71% Walch B2 classification; 12/17).

Posterior humeral subluxation improved at follow-up according to the Walch index (mean, 55.5% preoperative vs 48.5% postoperative), and contact point ratio (mean, 63.9% preoperative vs 50.1% postoperative). 

Significant pre- to postoperative improvements were seen shoulder outcome scores.

No signs of radiographic loosening were detected in follow-upimages, nor were there any postoperative instability episodes or revision surgeries.

Comment: This article does not report the amount (pounds) of weight being lifted by these patients before and after surgery, so that the loads involved cannot be quantitated.

The authors propose that the inlay glenoid component provides a more stable glenoid arthroplasty than the onlay glenoid commonly used in total shoulder arthroplasty. 

The inlay glenoid does not completely cover the glenoid articular surface as seen in this illustration from the technique guide

and this intraoperative photo

and this post operative film.

The small surface area of the glenoid component may be an issue. In the figure below from this article, the humeral head is not articulating at all with the prosthetic glenoid component that lies between the two red arrows.

The value of the inset glenoid component is yet to be demonstrated in comparison to the ream and run glenohumeral arthroplasty in which no glenoid component is used (how to do this procedure is seen in this link). See also

Ream and run for shoulder arthritis in a weight lifter

Shoulder arthritis in a body builder managed with a ream and run

How you can support research in shoulder surgery Click on this link.

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 total shoulder arthroplasty (see this link).

The ream and run technique is shown in this link.

The cuff tear arthropathy arthroplasty (see this link).

The reverse total shoulder arthroplasty (see this link).

Shoulder rehabilitation exercises (see this link).

Follow on twitter: Frederick Matsen (@shoulderarth)