Assessing the Value to the Patient of New Technologies in Anatomic Total Shoulder Arthroplasty
Publications regarding anatomic total shoulder arthroplasty (aTSA) have consistently reported that this procedure provides significant improvement for patients with glenohumeral arthritis.
New aTSA technologies introduced with the goal of further improving these outcomes include preoperative computed tomography (CT) scans, 3-dimensional preoperative planning, patient-specific instrumentation, stemless and short-stemmed humeral components, as well as metal-backed, hybrid, and augmented glenoid components. The benefit of these new technologies in terms of patient reported outcomes is unknown.
These authors reviewed 114 articles presenting preoperative and postoperative values for commonly used patient-reported measures of shoulder comfort and function. The results were analyzed to determine whether reported patient outcomes have improved over the 20 years during which new technologies became available.
While anatomic total shoulder arthroplasty was consistently associated with good patient outcomes, this analysis did not identify evidence that the results of aTSA were statistically or clinically improved over the two decades of study or that any of the individual technologies were associated with significant improvement in patient outcomes.
The figure below shows the average preoperative-to-postoperative change in SST score reported in each of 35 studies published over the last 2 decades. The linear trend line is shown; the change was not statistically significant. Also shown are two horizontal lines representing the lower and higher values for the MCID reported for the SST; note that the SST did not improve by the MCID.
The figure below shows the average preoperative-to-postoperative change in ASES score for each of 68 studies published over the last 2 decades. The linear trend line is shown; the change was not statistically significant. Also shown are two horizontal lines representing the lower and higher values for the MCID reported for the ASES; note that the ASES score did not improve by the MCID.
The figure below shows the average preoperative-to-postoperative change in Constant score for each of 61 studies published over the last two decades. The linear trend line is shown; the change was not statistically significant. Also shown are two horizontal lines representing the lower and higher values for the MCID reported for the Constant score; note that the Constant score did not improve by the MCID
The authors point on that in this review, the average postoperative score for the SST was approximately 10 points, a value within 2 points of a perfect SST score of 12 points. In order for a new technology to improve this outcome by an amount equal to the MCID (1.5 to 3.6 points), the average SST outcome score would need to be essentially a perfect 12 points.
Similarly, the average postoperative ASES score was 84 points, a value within 16 points of a perfect ASES score of 100 points. In order for an advance in technology to improve this outcome by an amount
equal to the MCID (13.5 to 29.5 points), the average outcome score would need to be essentially a perfect 100 points.
Finally, the average postoperative Constant score was nearly 70 points. For normal individuals 65 years old, the Constant score has been reported as being between 70 and 90 points61,62. Thus, for it to be improved by the MCID (5.1 to 17 points), a nearly perfect score would need to be achieved.
It seems unlikely that new technologies could improve the average patient outcomes by the MCID because much of the outcome of TSA is related to factors that new technologies cannot address, such as the patient’s medical, psychological, and socioeconomic health. One author suggested that "psychosocial factors may play just as important, if not more, a role in affecting patient outcomes after TSA as technical factors.”
New technologies and implant designs carry with them incremental costs above those of the legacy approaches that have been in standard practice. These costs include not only those associated with research, development, FDA approval, and marketing, but also the cost of surgeon time spent mastering the new technology and the cost of unexpected outcomes, such as difficulties in application and implant failure.
Therefore, the incremental value to the patient of each new technology requires careful study.
Here's a video that emphasizes the message.
