The Problem
Much of what we do in orthopaedic surgery has a high apparent success rate (85–90%). While encouraging, studies of shoulder arthroplasty, rotator cuff repair, and other interventions show that the proportion of patients achieving clinically meaningful improvements in comfort and function has not changed significantly for more than a decade.
This stagnation has persisted despite multiple innovations in technique, technology, implants, and biologics—which have been introduced often without clear evidence that they address the true causes of clinical failure.
Many of our colleagues believe that it is impossible to ferret out the causes of a failure requiring surgical revision because we were not there at the time of the original procedure.
On the other hand, my collegue Chris Ahmad, points out that
Step 1: Individual Case Analysis
Progress will depend on systematically examining the one in ten cases that require revision. The guiding question is:“Given what is known about this patient and procedure, what might have been done differently to reduce the risk of revision?”
Because the revising surgeon often did not perform the index surgery, she or he must reconstruct the case—much as aviation investigators reconstruct a crash. This requires integrating expertise and available evidence to specify plausible alternatives, knowing that many of the possible contributing factors cannot be accurately assessed (even if we have the "black box" or the operative note and preoperative images).
Key elements we should pursue include:
Patient and shoulder characteristics before the index surgery
Details of the index procedure
Surgical alternatives used in similar cases
Findings at revision
Recognized causal links between surgical choices and failure modes (e.g. inadequate fixation of the glenoid component).
Menu of Causes
To support structured causal reasoning, revising surgeons are presented with a menu of recognized causes of failure.
For anatomic shoulder arthroplasty, examples include:
Inappropriate implant sizing
Inadequate fixation
Poor component positioning
Insufficient balancing of the humeral head on the glenoid
Other to be specified by surgeon
The revising surgeon selects the most plausible cause(s) or adds others, then assigns a rating to each:
3 = Very likely contributed
2 = Possibly contributed
1 = Unlikely
0 = No opinion / insufficient information
Embracing Uncertainty
This method explicitly acknowledges uncertainty. Surgeons are not asked for certainty, but for their best judgment, made transparent:
“I cannot know with certainty what would have happened with an alternative procedure, but given the case information and the published evidence, the most plausible cause of revision of this surgery is inadequate glenoid component seating and fixation.”
By making explicit the judgments that surgeons already form implicitly, this framework brings rigor and transparency to causal reasoning.
Step 2: Progressively Building a Case Library
By indexing and pooling these structured case analyses across many revisions, we can identify patterns that no single surgeon’s memory or experience could reveal.
Aggregated data will show:
Causes consistently endorsed (e.g., “flawed fixation and seating = very likely”)
Causes inconsistently endorsed
Causes rarely implicated
This approach transforms anecdote into evidence.
Step 3: Sharing the Knowledge
As the indexed library grows, it will provide a searchable knowledge base—providing case-based evidence to inform surgeon decisions for future patients with the diagnosis in question.
The larger the library, the more refined the collective insights become. By presenting and publishing results, surgeons’ attention will increasingly focus on actions that demonstrably reduce the risk of revision.
We need to accept the mission.
Just because it's difficult is not a reason for not doing it.
Union Bay Natural Area
Spring 2022
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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).
