Two year outcomes for reverse total shoulder for osteoarthritis and the effect of survivorship bias.

How survivorship bias can affect reports of two-year outcomes

When we quote a two-year success rate for an operation, the figure typically describes the outcomes for the patients who came back to be assessed at two or more years after surgery.

Those who did not return are not a random sample of all the patients having the surgery. Patients lost to follow-up tend to have fared worse than those who complete follow-up, because the reasons they drop out are often themselves adverse — death, revision, or disappointment with an early result that leads them to transfer their care elsewhere [1, 2, 3].

Excluding patients who have done poorly prior to the two-year mark — considering only those who remain for the two-year analysis — makes the operation look better than it actually was, a phenomenon known as survivorship bias [4].

A model of survivorship bias

Here is an illustrative hypothetical example of a thousand patients having an RSA for cuff-intact osteoarthritis with two-year follow-up.

In the first six months patients were lost as follows: 20 shoulders revised, 5 patients dead, 15 transferred to another practice, and 40 who simply stopped responding — 80 in all. Of note, certain problems occur early in the postoperative period: acute infection, instability, acromial fracture, and life-limiting frailty.

During the second six months there were 7 more revisions and 8 deaths, 25 transfers, and 110 who did not respond for unknown reasons — 150 in the interval.

The second-year losses are almost entirely loss of contact rather than loss of the shoulder: 3 revised and 12 more dead, 35 gone to other practices, and 200 more who stopped answering — 250 in that interval.

By the time of the two-year analysis, 30 of the 1,000 have been revised, 25 have died, and 75 have transferred their care; 350 more have gone quiet without a recorded reason. That is 480 lost from view, none of whom are included in the two-year analysis of results; only 520 remain available for study.

Figure 1. A hypothetical cohort of 1,000 patients followed over two years. At each interval, patients drop out of view for four kinds of reasons, and the mix changes as time passes. Of the 520 analyzed at two years, 9 out of 10 report success; but out of all 1,000 operated on, a successful outcome is documented for only about 4.7 out of every 10.

The four reasons carry different weight, and their proportions change over the two years. Revisions come early: RSA’s dominant early failures — acute infection, instability, and acromial fracture — appear mostly in the first months, so revisions decline from 20 in the first half-year to 3 in the second year. Deaths run the other way, accumulating with time in an elderly group, from 5 to 8 to 12 across the intervals. Transfers of care, and above all patients who simply stop responding, grow steadily as contact is lost — from 40 silent patients in the first six months to 200 in the second year. By the time of the two-year analysis, loss of contact, not loss of the shoulder, accounts for most of the missing.

Applying the model of survivorship bias to actual data on two-year outcomes for RSA for osteoarthritis

The model becomes meaningful when anchored to what the literature reports. Two published figures set the scale.

The first is the rate of two-year follow-up. In a multicenter shoulder arthroplasty registry, only about half of patients — about 5 out of 10 — provided two-year patient-reported outcomes [5]; registries that send repeated reminders might improve the return to  8 out of 10.

The second is the success rate among those who do return: in high-volume single-surgeon series of RSA for this diagnosis, about 9 out of 10 report being better and satisfied [6, 7].

Consider the combined effect of these two rates. Of the 520 with a known two-year result, 9 out of 10 — 468 patients — report success; but across the full 1,000 who had the surgery, those 468 provide an overall documented success rate of only about 4.7 out of 10.

Had the follow-up rate reached 8 out of 10 rather than 5, about 800 would have a known result, and the same 9 out of 10 would give about 720 documented successes — roughly 7 out of 10.

The span from 4.7 to 7 out of 10 is set entirely by the follow-up rate.

The 4.7 out of 10 is the floor. It counts every patient without a documented success as a non-success, so that the true whole-cohort success rate (if it could be known) might be higher than 4.7 out of 10. 

The missing patients are not a random subset of the cohort. Those lost to revision, death, or a transfer of care each had reason to fare worse than the returners. The larger unresponsive group has, on average, done less well than those who answer — though that association is weaker and less certain than for the other types of losses [1, 2, 3].

Reporting the returners’ 9 out of 10 as the rate for the overall cohort makes the operation look better than the data support [4].

However,  a successful outcome is only documented for about 5 of every 10  patients considering all those having the surgery, not 9 out of 10.

A fuller accounting would mean following the patients who leave — the revised, the transferred, and above all the ones who quietly stop answering — well enough to know how they actually did. Until a series does that, the appropriate two-year estimate for successful outcome for RSA in osteoarthritis is somewhere above the documented 4.7 out of 10 rate for the entire cohort and below the rate of 9 out of 10 considering only the patients returning for two year analysis. 

And two years is the favorable case. The effect of survivorship bias grows as follow-up lengthens: over five, ten, and fifteen years, follow-up falls further and the number of missing patients grows, so the distance between the returners’ success rate and the whole-cohort success rate only widens. The longer the follow-up a reported success rate claims, the greater the effect of survivorship bias.

It's about survivorship

Bald eagles

Montlake Cut

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References

[1] Solberg TK, Sørlie A, Sjaavik K, Nygaard ØP, Ingebrigtsen T. Would loss to follow-up bias the outcome evaluation of patients operated for degenerative disorders of the lumbar spine? A study of responding and non-responding cohort participants from a clinical spine surgery registry. Acta Orthop. 2011;82(1):56–63.

[2] Murnaghan ML, Buckley RE. Lost but not forgotten: patients lost to follow-up in a trauma database. Can J Surg. 2002;45(3):191–195.

[3] Torrens C, Martínez R, Santana F. Patients lost to follow-up in shoulder arthroplasty: descriptive characteristics and reasons. Clin Orthop Surg. 2022;14(1):112–118.

[4] Elston DM. Survivorship bias. J Am Acad Dermatol. Published online June 18, 2021.

[5] Patel M, Sekar MG, McDaniel L, Kisana HM, Sykes JB, Amini MH. Changes from baseline in patient-reported outcomes and patient satisfaction do not vary significantly between 1 and 2 years postoperatively after shoulder arthroplasty: a multicenter analysis of 2580 patients. Semin Arthroplasty JSES. 2025;35(2):235–245.

[6] Puzzitiello RN, Moverman MA, Glass EA, Swanson DP, Bowler AR, Le K, Kirsch JM, Lohre R, Jawa A. Clinically significant outcome thresholds and rates of achievement by shoulder arthroplasty type and preoperative diagnosis. J Shoulder Elbow Surg. 2024;33(7):1448–1456.

[7] Ahmed AF, Glass EA, Swanson DP, et al. Predictors of poor and excellent outcomes following reverse shoulder arthroplasty for glenohumeral osteoarthritis with an intact rotator cuff. J Shoulder Elbow Surg. 2024;33(6S):S55–S63.

Pyrocarbon in the Shoulder: what we think we know. Section 2

As a sequel to the prior post (Section 1), here is a look at the literature on clinical results for the pyrocarbon shoulder implants. Results can be expressed as (a) revision rate and (b) patient-reported outcomes (PRO). At the outset we recognize that lack of a revision is not the same as a clinically significant improvement (i.e., improvement in PRO that exceeds the minimal clinically important difference, MCID). Lack of a revision may result from patient unwillingness to undergo another procedure, patient lost to follow-up, poor patient health, or patient death — none of which indicate a clinically significant improvement.

An issue confounding the available clinical results for pyrocarbon implants is that reports often combine legacy devices, revised versions, and current instantiations.

PYRO TYPE 1: PROXIMAL HUMERAL RESURFACING (PHR/PYROTITAN)

This implant has been through at least three significant design iterations and three commercial sponsors. None of the published papers isolates the current implant configuration. Every survivorship figure in the literature pools generations. The lineage, reconstructed from the McBride 2026 paper [1], the Hoy 2026 paper [2], the Therapeutic Goods Administration hazard alert [3], and contemporaneous trade press, is summarized in the following table.

The McBride 2026 registry cohort (n = 403, enrolled 2004–2022) spans all three iterations; and the reported 35%-of-revisions-from-breakage figure averages performance across known-fracture-prone implants and the current design.[1] The Hoy 2026 cohort (n = 119, enrolled January 2013–November 2023) starts at about the time of the TGA hazard alert; the earliest patients received the first-redesign implant; mid-cohort patients received the second-redesign implant, and late patients received the current implant.[2] Thus, the result for the current commercially available PHR/PyroTITAN implant is unknown. It cannot be extracted from the existing literature because every published series pools at least two device generations.

Here is what relates to the post-2017 third design:

Survivorship:  cumulative percent revision (CPR) 7.7% at 10 yr (McBride 2026 [1]); 5-year Kaplan–Meier survivorship 97.5% (mean follow-up 34.6 months) (Hoy 2026 [2]). Manufacturer filings (not peer-reviewed): Kaplan–Meier survival ~86% up to ~117 mo as posted to ClinicalTrials.gov (NCT02405208 [9]). The primary endpoint of NCT02983292 [8] is device survival, not patient-reported outcomes; results are not yet published.

Effectiveness:  WOOS 38→83 and ASES 49→87, all exceeding MCID (Hoy 2026 [2]).

PYRO TYPE 2: THE U.S. STEMMED PYROCARBON HEMIARTHROPLASTY (HA-PYC)

The FDA Investigational Device Exemption study [4] enrolled patients between December 2015 and April 2017, before the final round of design changes. The De Novo clearance was granted in 2022, and U.S. commercial use of the pyrocarbon humeral head began only in March 2023. The Griswold 2025 JBJS paper [5] reports the IDE patients at 5 years, not the post-clearance commercial cohort.

Survivorship:  3 of 157 revised before 24 mo, mean follow-up 24.4 mo; 3-year Kaplan–Meier revision-free survival 96.6% (Hatzidakis 2026 [4]). In the same IDE lineage followed forward (n = 45, mean follow-up 73 mo), 7-year revision-free survival 95.7% and failure-free survival 93.4% — the 2 revisions were both for infection (Griswold 2025 [5]).

Effectiveness:  Composite Clinical Success 82.7%, defined as a ≥17-point Constant-score improvement without revision or device-related adverse event; ASES 44→88, adjusted Constant 51→91, SANE 36→85 (Hatzidakis 2026 [4]). At ≥5 years (mean 73 mo): ASES 47→96, SANE 39→94, Constant 48→88, all exceeding MCID, with glenoid morphology stable between the 2-year and final imaging (Griswold 2025 [5]).

PYRO TYPE 3: THE EUROPEAN STEMMED PYROCARBON HEMIARTHROPLASTY

The European cohort, followed a mean of 5.6 years [6], pools shoulders implanted before and after the systematic head-downsizing maneuver that became standard once Cointat reported that nonanatomic reconstruction (center of rotation > 3 mm off the anatomic center) occurred in 29% of cases and was strongly associated with glenoid erosion and revision [7].

With the current downsizing technique (Boileau 2026 [6]):

Survivorship:  revision-free survival 94% at 5 yr and 89% at 10 yr.

Effectiveness:  Constant 29→77, SSV 25%→84%, 91% return to work, 88% return to sport.

SUMMARY

Pyrocarbon shoulder arthroplasty is an exciting technology that is rapidly evolving. While evolution to address clinical issues (fracture, overstuffing, component malposition) is critical, it does confound the study of clinical outcomes: the implants on which follow-up data are available are often not the ones in current use. Once the designs and techniques have stabilized, data on revision rates and patient-reported outcomes for them will be of great interest.

Black vulture

San Antonio

2025

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REFERENCES

1. McBride A, Hurley R, Gill D, Du P, Duke P, Taylor F, Hoy G, Page R, Ross M. Outcomes of pyrolytic carbon humeral resurfacing hemiarthroplasty compared to best-in-class total shoulder arthroplasty in young patients with osteoarthritis: analysis from the Australian Orthopaedic Association National Joint Replacement Registry. J Shoulder Elbow Surg. 2026;35(5):1209–1218. doi:10.1016/j.jse.2025.09.007.

2. Hoy G, Burrows K, McBride A, Ross M, Davis K, Warby S. PyroTITAN Pyrocarbon Shoulder Hemiarthroplasty: Clinical and Radiographic Outcomes with Medium-Term Follow-up. J Bone Joint Surg Am. Epub 2026 May 13. doi:10.2106/JBJS.25.00779.

3. Therapeutic Goods Administration. PyroTitan humeral resurfacing arthroplasty — hazard alert. Canberra, Australia: Australian Government Department of Health; August 2013. Available at: https://www.tga.gov.au/safety/recalls-and-other-market-actions/market-actions/pyrotitan-humeral-resurfacing-arthroplasty (LMT Surgical, 3% worldwide implant breakage rate, sub-surface fractures identified).

4. Hatzidakis AM, Garrigues GE, Mauter LA, de Gast A, Venegoni MR, Yang Y, Johnston PS. Clinical Outcomes of Pyrocarbon Hemiarthroplasty: A Short-Term, Multicenter Study. J Bone Joint Surg Am. 2026;108(8):572–583. doi:10.2106/JBJS.25.00054.

5. Griswold BG, Berger JM, Davis BP, Mauter L, Boyd M, Schuette HB, Johnston PS, Sears BW, Hatzidakis AM. Five-Year Radiographic and Clinical Outcomes of Pyrocarbon Hemiarthroplasty for Glenohumeral Arthritis and Osteonecrosis. J Bone Joint Surg Am. 2025;107(24):2751–2762. doi:10.2106/JBJS.25.00163.

6. Boileau P, Cointat C, Raynier JL, Schippers P, Ranieri R. Pyrocarbon hemiarthroplasty for the treatment of shoulder osteoarthritis in young, active patients: survival and risk factors for revision. J Shoulder Elbow Surg. 2026;35(2):421–437. doi:10.1016/j.jse.2025.06.021.

7. Cointat C, Raynier JL, Vasseur H, Lareyre F, Raffort J, Gauci MO, Boileau P. Short-term outcomes and survival of pyrocarbon hemiarthroplasty in the young arthritic shoulder. J Shoulder Elbow Surg. 2022;31(1):113–122. doi:10.1016/j.jse.2021.06.002.

8. ClinicalTrials.gov. A Clinical and Radiological Study to Evaluate the Safety and Efficacy of the PyroTITAN Humeral Resurfacing Arthroplasty (HRA) Device in a New Cohort of Patients After Product Re-Release (T-HRA-003). NCT02983292. Sponsor: Smith & Nephew. Completed February 2023; results posted to ClinicalTrials.gov 2024 (not peer-reviewed). https://clinicaltrials.gov/study/NCT02983292.

9. ClinicalTrials.gov. A Multi-center Outcomes Clinical Study of the PyroTITAN HRA Shoulder Implant in Humeral Head Resurfacing (CP-HRA-002). NCT02405208. Sponsor: Smith & Nephew. Enrollment 156; completed September 2023; results posted to ClinicalTrials.gov 2025 (not peer-reviewed). https://clinicaltrials.gov/study/NCT02405208.

How long does a shoulder replacement last?

  ChatGPT is a interactive language model developed by OpenAI, that uses a deep learning framework to understand queries and to generate coherent, contextually relevant responses based on a set of books, websites, and texts selected by researchers at OpenAI. While search engines such as Google provide links to websites that may or may not be accurate or relevant, ChatGPT provides a readable synthesis of the information from its comprehensive sources,

We sought ChatGPT responses to questions frequently posed by patients with shoulder arthritis.  These responses cannot used as specific medical advice. Patients should consult medical professionals for the most current and accurate information on their shoulder condition.

We asked "How long does a shoulder replacement last?"

ChatGPT responded:


"The lifespan of a shoulder replacement can vary depending on several factors, including the patient's age, overall health, activity level, and the type of prosthesis used. On average, a shoulder replacement can last between 15 to 20 years. However, advancements in surgical techniques and implant design have led to improved longevity in recent years.

It's important to note that these estimates are based on current research and clinical data, but individual results may vary. Some factors that can affect the lifespan of a shoulder replacement include wear and tear over time, the patient's activity level, the presence of other medical conditions, and the overall health of the patient's bone and soft tissues surrounding the implant.

Regular follow-up visits with your orthopedic surgeon and adherence to any post-operative guidelines can help ensure the longevity and success of a shoulder replacement. If you have concerns about your shoulder replacement or its lifespan, it's best to consult with your orthopedic surgeon who can provide specific information based on your individual case."

You can support cutting edge shoulder research that is leading to better care for patients with shoulder problems, click on this link.

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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)

How long do total shoulders last? The Great Paradox

Survival of the pegged glenoid component in shoulder arthroplasty: part II

Theses authors point out that loosening of the glenoid component is a primary reason for failure of an anatomic shoulder arthroplasty. These authors evaluated the midterm clinical and radiographic survival of an in-line pegged glenoid component and identified risk factors for radiographic loosening and clinical failure at an average clinical follow-up of 7.2 years

287 had presurgical, initial postsurgical, and late postsurgical radiographs (mean radiographic follow-up, 7.0 years). At most recent follow-up, 30 glenoid components had been revised for aseptic loosening. The rate of glenoid component survival free from revision for all 330 shoulders of 99% at 5 years and 83% at 10 years. 

Of 287 glenoid components, 120 (42%) were considered loose on the basis of radiographic evaluation. Four humeral components were considered loose. Component survival (Kaplan- Meier) free from radiographic failure at 5 and 10 years was 92% and 43%. 

Severe presurgical glenoid erosion (Walch A2, B2, C) and patient age <65 years were risk factors for radiographic failure. Late humeral head subluxation was associated with radiographic failure.

Comment: This paper shows the importance of longer term followup. Both radiographic failure and the need for surgical revision for this component was not apparent until after five years - a time well after the usual 2-year followup required for publication in most journals. 

This article also points out that the rate of revision at any time point after surgery underestimates the rate of radiographic glenoid failure.

A case example from this paper shows late loosening of an initially well-fixed glenoid component

 The late followup x-ray shows superior displacement of the humeral head with superior angulation of the glenoid component.

This is the type of component loosening that has been associated with rotator cuff failure via the 'rocking horse' mechanism.

The authors point out that their results with this peg configuration were inferior to those they achieved with the corresponding keeled fixation.

One of the challenges we face in clinical orthopaedic research what we refer to as the Great Paradox: the long term data we have relates to components that are no longer in use.

The authoring surgeons have moved on to other designs for which 10 year outcomes are not available:

Nevertheless, the problem of glenoid component failure retains its position as a leading cause of poor total shoulder outcomes. Some of the risk factors for failure identified in this study are likely to remain in effect with any glenoid component design: young age, advanced glenoid erosion, and glenohumeral instability. 

Finally, an understanding of the factors associated with component failure may be most reliably obtained from national registry data such as that provided by the Australian Orthopaedic Association 

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The reader may also be interested in these posts:

Healing through joint replacement

Supporting progress in shoulder surgery

Consultation for those who live a distance away from Seattle.

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Information about shoulder exercises can be found at this link.

Use the "Search" box to the right to find other topics of interest to you.

You may be interested in some of our most visited web pages including:shoulder arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery as well as the 'ream and run essentials'

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Shoulder arthroplasty: patient satisfaction vs. implant survival

Evaluation of satisfaction and durability after hemiarthroplasty and total shoulder arthroplasty in a cohort of patients aged 50 years or younger: an analysis of discordance of patient satisfaction and implant survival.

These authors reviewed their cases of primary hemi and total shoulder arthroplasty in patients 50 years or younger that had at least two years of followup, comparing clinical outcomes with component survivorship. Importantly, the choice between hemi and total shoulder arthroplasty was made by the surgeon  based on multiple factors including etiology of arthritis and coexisting anatomic factors, such as the structural  condition of the glenoid and decentering of the humeral head, as well as patient activity level. 

Patient satisfaction survival was based on yes or no answers to 2 binary questions regarding willingness to undergo surgery again and whether surgery improved the patient's shoulder. Multivariable regression analysis implicated postoperative pain as the primary causative factor for failure of patient satisfaction in all patients.

The Kaplan-Meier patient satisfaction survival rates at 5 years were 71.6% for hemiarthroplasties and 95% for TSAs.  The implant survival rates at 5 years were 89% for HAs and 95%.

Self-reported satisfaction declined for both procedures five or more years after arthroplasty while no patients had a revision after 2.5 years. The authors caution that studies and registries must incorporate measurements of patient satisfaction and not just revision rates to truly interpret outcomes.

Comment: The hemiarthroplasty and the total shoulder groups were not comparable, so that conclusions cannot be made regarding the relative effectiveness of the two procedures. For example only 48% of the hemiarthroplasties were in male patients while 70% of the total shoulders were in males (who are known to have better shoulder arthroplasty outcomes than females);  only 51% of the hemiarthroplasties were performed for osteoarthritis while 75% of the total shoulder arthroplasties were performed for osteoarthitis (which is known to have better outcomes than other diagnoses).

For this reason the authors' statement that "Overall, it appears that primary TSA outperforms HA in young patients in terms of implant longevity, patient outcomes, and cost-effectiveness" is not supportable by the data in this study.

"Implant survivorship" is a temptingly easy metric to use in studies of implant databases. However, as this paper demonstrates, the fact that the patients choose to retain their implant does not mean that they are satisfied with the clinical result. Perhaps they were unwilling to subject themselves to another surgery after the failure or they could not find a surgeon willing to perform a revision.

Since the goal of shoulder arthroplasty is to improve the patient self-assessed comfort and function of the arthritic shoulder, the most relevant outcome measure is the improvement in a metric such as the Simple Shoulder Test, rather than the patient's decision to avoid revision.

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Consultation for those who live a distance away from Seattle.

Click here to see the new Shoulder Arthritis Book

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Use the "Search" box to the right to find other topics of interest to you.

You may be interested in some of our most visited web pages including:shoulder arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery as well as the 'ream and run essentials'

See from which cities our patients come.

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Shoulder arthroplasty - survivorship - is this the right methodology?

Improved survival for anatomic total shoulder prostheses.

These authors studied 4,173 patients with shoulder replacements reported to the Norwegian Arthroplasty Register (2,447 hemiprostheses, 444 anatomic total prostheses, 454 resurfacing prostheses, and 828 reversed total prostheses) performed for osteoarthrtis, rheumatoid arthritis, acute fracture, and fracture sequelae.

Our summary of their data is shown below as the 5 and 10 year prosthesis revision rates.

They also found that patients over 70 years of age and female patients had lower prosthesis revision rates. The brand of prosthesis and type of fixation also had effects on revision rates. 

The reasons for revision are shown here:

Comment: These data cry out for a multivariate analysis. It is apparent that the type of prosthesis selected by the surgeons were not independent of other factors, such as diagnosis. Without this we cannot know which of the following factors were most important in the revision rate: type of procedure, diagnosis, age, sex, cementation, prosthesis brand or date of surgery. 

Also, as we've pointed out before, prosthesis revision is a peculiar type of endpoint - it depends on the patient's willingness to subject to another surgery when the first one failed. Some patients prefer to accept a poor functional outcome rather than rolling the dice again. This study did not include functional outcomes.

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Consultation for those who live a distance away from Seattle.

Check out the new Shoulder Arthritis Book - click here.

Click here to see the new Rotator Cuff Book

Use the "Search" box to the right to find other topics of interest to you.

You may be interested in some of our most visited web pages including:shoulder arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery as well as the 'ream and run essentials'

See from which cities our patients come.

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Revision rate, survivorship, total shoulder

In outcome studies of shoulder arthroplasties we often use revision as the endpoint as a determination of 'survivorship'. While there is no question that this endpoint is 'objective', the case below shows that the time to revision is actually subjective. 

In 1996 the patient had a shoulder arthroplasty with a press fit stem and a cemented polyethylene glenoid component for rheumatoid arthritis. The initial films are no longer available. 

Twelve years after surgery, at the age of 69 reporting that she had done very well with this for quite some time and was really having no difficulties with it until approximately 3-4 months prior to the visit. She wanted to begin working out at the Y and began experiencing increasing pain in her left shoulder. She stated that her pain was 5/10 and gradually worsening. She described it as sharp, exacerbated by activity. Rest and immobilization improved her pain. At that time her x-rays showed loose glenoid and humeral components

 She did not wish a revision. Fourteen years after surgery she returned with ongoing discomfort and with these films.

 Same story at 16 years, note the medial migration of the glenoid component.

 At 17 years she asked for a revision

At surgery she had severe osteolysis of the glenoid precluding replacement of a glenoid component and extremely fragile bone of the proximal half of the humerus. We used a long stem humeral prosthesis cemented in the distal third of the humerus and copious cancellous allograft proximally.

The point of this post is that her time to revision or the survivorship of the implant depended not on when the prosthesis failed (objective), but when the patient decided to have surgery (subjective). This emphasizes the point we've made in the past, the rate of failure is greater than the rate of revision.

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To learn more about shoulder arthritis and what can be done about it, see the Shoulder Arthritis Book.

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To see the topics covered in this Blog, click here

Use the "Search" box to the right to find other topics of interest to you.

You may be interested in some of our most visited web pages including:shoulder arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, androtator cuff surgery as well as the 'ream and run essentials'

See from which cities our patients come.

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Keeled glenoid survivorship in young patients

Mid- to long-term follow-up of total shoulder arthroplasty using a keeled glenoid in young adults with primary glenohumeral arthritis.

The purpose of this study was to examine the mid- to long-term functional outcome and implant survival of total shoulder arthroplasty in patients under the age of 56 years with primary glenohumeral arthritis. Between 1992 and 2004, surgeons in 8 centers performed 52 such arthroplasties. Minimum follow-up of 5 years was available in 50 patients at a mean of 115.5 months postoperatively.

At a mean of 115.5 months, 37.5% of glenoids showed no loosening, 18.8% showed possible loosening, and 43.8% had definite radiologic loosening. Survivorship of the glenoid component with the endpoint being revision surgery for glenoid loosening was 98% at 5 years but declined to 62.5% at 10 years. When the humeral head was not positioned anatomically, the glenoid was 6.6 times more likely to require removal. The 10-year survival rate was 87.5% for glenoids that were concentric before surgery (A1 and A2) and only 50% for non-concentric glenoids (B1 and B2). All of the revisions were in the dominant arm.

Comment: The management of the arthritic shoulder, especially those with type B glenoids in individuals under the age of 56 years remains a challenge. While total shoulder is one option, the ream and run has also been used in this age group with encouraging results, especially in patients without prior surgical procedures on that shoulder.

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Use the "Search" box to the right to find other topics of interest to you.

You may be interested in some of our most visited web pages including:shoulder arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery as well as the 'ream and run essentials'


See from which cities our patients come.


See the countries from which our readers come on this post.

Comparison of Ten-Year Survivorship of Hip Prostheses with Use of Conventional Polyethylene, Metal-on-Metal, or Ceramic-on-Ceramic Bearings JBJS

What does "Comparison of Ten-Year Survivorship of Hip Prostheses with Use of Conventional Polyethylene, Metal-on-Metal, or Ceramic-on-Ceramic Bearings" have to do with total shoulders?

High complements go to the authors from the Valdoltra Orthopaedic Hospital in Ankaran, Slovenia for their long term followup of 487 hips in 469 patients.

This is a most interesting article in that it shows (1) long-term followup is critical for the assessment of the results of joint arthroplasty and (2) "new" is not necessarily better.  As we saw in an earlier post, a large Australian registry showed that some of the newer shoulder arthroplasty designs had higher revision rates than their predecessors. In this article about total hips, the survivorship was determined as the time to revision for any reason.  The authors found that the newer ceramic on ceramic (CoC) bearing surface systems did not outperform conventional metal on polyethylene (MoP). The newer metal on metal (MoM) bearing surfaces had significantly worse survivorship than conventional metal on polyethylene. Their results are nicely summarized in their figure below showing survivorship by year.

Of great importance in this figure is the fact that had the study been concluded at 6 years of followup, it is doubtful than any difference would have been noted. Patients expect long term performance, we need to provide long term followup.

The other important point is that lots of money is spent on developing newer prostheses, for the hip, knee and shoulder - money on research, development, FDA approval, marketing, consultancy and royalties. Imagine what the total figures might be for MoM or CoC hips. These monies are recovered from patients and their insurances. We need to keep a close eye on the value (benefit/cost) of innovation so that health care dollars are spent wisely. New designs bring new risks. CoC bearings introduce the risk of ceramic fracture. MoM bearings introduce the risk of metal debris and increased serum ion levels. 

These authors found a survivorship of 0.984 at ten years for conventional MoP bearings. New designs have to be pretty spectacular to surpass that.

In total shoulder arthroplasty, the principal cause of failure is the glenoid component, yet most 'new' generations of arthroplasty represent changes in the design and increased complexity of the humeral component. It is time to refocus efforts on where the problem lies and to put innovation to the test of long term followup as our colleagues in Slovenia have done for hip arthroplasty.

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complications and survivorship in shoulder arthroplasty

The JSES recently published an article on factors predicting complications after primary hemi and total shoulder arthroplasty. Their study was based on data for all hospital discharges within the state of California in the years 1995 through 2005 were obtained from the California Office of Statewide Health Planning and Development (OSHPD), a mandatory database compiled annually by the state, and all nonfederal acute care hospitals within California containing discharge abstracts for every inpatient admission, regardless of insurance type. Auditing rules are in place to identify potentially erroneous batches of records, and a sample of the records is also audited for accuracy.

They found 15,288 patients having shoulder arthroplasty. There was no significant difference between patients undergoing total shoulder arthroplasty and hemiarthroplasty with respect to the aggregate risk of 90-day complications or the risk of implant failure within the study period. Patients having arthroplasty for fracture were shown to have a higher risk of short-term complications (odds ratio, 3.2; P < .001). Implant failure rates were lower in patients with fracture, rheumatoid arthritis, increased comorbidity, and advanced age. The overall mortality rate was 1.3%, and the pulmonary embolism rate was 0.6%.

The authors note that a variety of different complications can be encountered with shoulder arthroplasty. The most common include prosthetic loosening, glenohumeral subluxation or dislocation, periprosthetic fractures, infection, and neurovascular injury. They summarize the literature as showing an overall 14.7% complication rate, with component loosening (6.3%), particularly of the glenoid (5.3%), to be the most common.

Their finding that longer-term, implant survival is largely driven by factors associated with increased activity, such as age, suggests that there is a need for arthroplasty methods that are better suited for individuals wishing to remain active for long periods of time after surgery.  This is the motivation for our pursuit of the ream and run procedure.

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Use the "Search the Blog" box to the right to find other topics of interest to you.

You may be interested in some of our most visited web pages including: shoulder arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery.

See the countries from which our readers come on this post.