Baseplate failure is an important cause of failure of reverse total shoulder arthroplasty.
As these x-rays demonstrate, the reverse total shoulder is vulnerable because the baseplate has to resist the upward directed force applied by the humeral component on the glenosphere.
This load is resisted by (1) secure fixation of screws in good quality native glenoid bone (green arrows) and (2) compression of the superior aspect of the baseplate against prepared glenoid bone (yellow arrow).
In other words, good carpentry
the absence of which risks baseplate failure
A recent article from the American Shoulder and Elbow Surgeons,
Surgical and Patient Factors Associated with Baseplate Failures After Reverse Shoulder Arthroplasty: A Study by the ASES Complications of RSA Multicenter Research Group aimed to identify surgical, implant, and patient-related risk factors for baseplate failure after reverse total shoulder.
Among 5,049 cases of rTSA followed for a minimum of 3 months, baseplate failure (defined radiographically as gross baseplate shift or hardware breakage) was identified in 83 (1.6%) cases at a median of 72 weeks post-surgery. These cases came from 40 centers performing large numbers of rTSAs, thus this rate is likely to substantially underestimate the actual rate of baseplate failure for all surgeons and patients.
Because of the hardship experienced by patients with baseplate failure, we must learn from these cases how the risk of failure can be reduced: "what could the operating surgeon have done differently to avoid this complication?"
Most failures (76%) were atraumatic, suggesting either insecure initial fixation, lack of ingrowth or both. Radiographs showed hardware breakage in 68.7% of failures. Baseplate shift occurred in 78.3% of cases. Revision arthroplasty had an odds ratio for baseplate failure of 4.57.
The actionable intelligence comes from the analysis of surgeon controlled variables: in primary rTSA, the risk of base plate failure was increased by the use of bone grafting (OR 4.42) and increased glenoid-sided lateral offset (OR 1.07). Central screw fixation (in contrast to use of peg or post) reduced failure risk (OR 0.55). In revision rTSA, only bone grafting remained significant (OR 3.75). Allograft use led to higher failure rates than autograft (14.7% vs. 3.9%).
Comment: In each case of reverse total shoulder arthroplasty there is an interplay between the quantity, quality and shape of native glenoid bone, the implants to be used and the experience and expertise of the surgeon.
Each surgeon needs to answer key questions for each case: In my hands, can reaming of the available native bone provide sufficient screw fixation and backside support for baseplate stability and ingrowth? Will the use of augmented components improve baseplate fixation? In which cases is structural grafting needed to manage large uncontained bone loss?
When a patient experiences baseplate failure, the surgeon must ask, "what could I have done differently to avoid this failure. Each failure needs to inform that surgeon's management of future cases.
The Surgeon is the Method
Osprey using experience and expertise
Seattle
UW Campus
2024
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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).
