Stemless total shoulder - is there spin in the abstracts?

Recently I've posted on 

Spin in abstracts on the subacromial balloon

Spin in abstracts on the augmented glenoid

Spin in abstracts on superior capsular reconstruction

Now we have the opportunity to consider spin in abstracts on the stemless total shoulder arthroplasty 

The stated goal of Evaluation of Spin in the Abstracts of Systematic Reviews and Meta-Analyses of Stemless Total Shoulder Arthroplasty was to identify and detail incidence of spin in the abstracts of systematic reviews and meta-analyses of stemless component total shoulde arthroplasty (TSA). The secondary goal was to investigate general study characteristics and describe patterns in relation to spin.

The authors point out that surgeons tend to read only the abstracts of publications, thus assessing spin in abstracts is important.

The details of their analysis is similar to that presented in Spin in abstracts on the augmented glenoid.

Basically the types of spin are:

Authors hide or do not present any conflict of interest 

Selective reporting of or overemphasis on efficacy outcomes or analysis favoring the beneficial effect of the experimental intervention 

Selective reporting of or overemphasis on harm outcomes or analysis favoring the safety of the experimental intervention 

Failure to specify the direction of the effect when it favors the control intervention 

Failure to report a wide confidence interval of estimates 

The conclusion claims the beneficial effect of the experimental treatment despite a high risk of bias in primary studiesThe conclusion claims the beneficial effect of the experimental treatment despite reporting bias. 

The conclusion formulates recommendations for clinical practice not supported by the findings 

The conclusion claims safety based on non-statistically significant results with a wide confidence interval 

The conclusion focuses selectively on statistically significant efficacy outcome 

The conclusion claims equivalence or comparable effectiveness for non-statistically significant results with a wide confidence interval 

The conclusion extrapolates the review findings to a different intervention (e.g., claiming efficacy of one specific intervention although the review covered a class of several interventions) 

Conclusion extrapolates the review's findings from a surrogate marker or a specific outcome to the global improvement of the disease 

Conclusion extrapolates the review's findings to a different population or setting 

The authors analyzed 12 articles. At  least 1 form of spin was observed in 10/12 (83.3%) studies. The most common type of spin was

“The conclusion claims the beneficial effect of the experimental treatment despite a high risk of bias in primary studies”, which was found in 7/12 (58.3%) studies. 

The three other common types of spin identified were

"The conclusion claims safety based on non-statistically significant results with a wide confidence interval"

"Authors hide or do not present any conflict of interest" 

"The conclusion formulates recommendations for clinical practice not supported by the findings"

According to  AMSTAR 2, 11/12 (91.7%) of studies had confidence ratings of “low” or “critically low” due to one or more critical flaws.

The authors concluded that "spin is prevalent in abstracts of systematic reviews and meta-analyses covering stemless TSA. Reporting more favorable outcomes is the most common type and physicians should be aware of this when making clinical decisions based on research". Authors tended to neglect the evaluation of primary study bias in their methodology; instead the discussion focused mainly on advantages of the stemless design.

Risk of overestimating the clinical importance of the stemless component TSA due to spin is especially relevant when contextualized within current literature on the topic. Romeo et al and Wiater et al recently performed two large, multicenter, prospective, blinded randomized controlled trials evaluating short-term clinical and radiographic outcomes of stemless implants against their traditional stemmed counterparts. Both studies found a lack of significant difference between stemmed and stemless component clinical outcomes, complications, and reoperation rates within a 2-year follow-up period. Additionally, the authors were careful to describe stemless implant performance as “noninferior,” “safe,” “effective,” or “promising.”Their findings are in contrast to the beneficial effect spinning that was most pervasive across the systematic reviews analyzed in the current study and suggest a pattern of overly optimistic conclusion-drawing despite RCTs that do not yet paint such a positive picture of the stemless technology.

Conclusion:

This study does not provide new evidence of the case for or against the use of a stemless humeral component. It does suggest that authors should attempt to avoid spinning their abstractions by making sure that the conclusions regarding safety and clinically (not only statistically) significant benefit are supported by robust evidence and that conflicts of interest and other sources of bias are made explicit.

Spin is not always bad, here are male and female redtail hawks spinning in courtship.

Red tailed hawks courting

Union Bay Natural Area

March 2021

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

Follow on twitter/X: https://x.com/RickMatsen
Follow on facebook: https://www.facebook.com/shoulder.arthritis
Follow on LinkedIn: https://www.linkedin.com/in/rick-matsen-88b1a8133/

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).

Spinning the data on the value of glenoid augmentation - a guide for authors of systematic reviews and meta-analyses

In the previous post we discussed the challenges in doing clinically significant research on shoulder arthroplasty.

As a follow-on, here we focus on the importance of the way research is presented, with particular reference to spin – defined as bias that overstates efficacy and/or underestimates harms of a treatment. Systematic reviews and meta-analyses are at risk for spin if there was bias in the primary studies on which they were based. 

There is the potential for spin in any presentation of outcomes. Evaluation of spin in reviews of biodegradable balloon spacers for massive irreparable rotator cuff tears found that 93.1% of the 29 included studies had at least one type of spin. See other examples of spin in our literature on this post. 

A recent article provides a useful guide to the elements of spin and how to avoid them.

The authors of Evaluation of Spin in Systematic Reviews and Meta-Analyses Involving Glenoid Augmentation in Total Shoulder Arthroplasty assessed the quantity and types of spin in systematic reviews and meta-analyses of glenoid augmentation in shoulder arthroplasty. They searched for each of 15 types of spin (see A new classification of spin in systematic reviews and meta-analyses was developed and ranked according to the severity). At least one form of spin was identified in 13 (81.3%) of the 16 studies. 

“The conclusion claims the beneficial effect of the experimental  treatment despite a high risk of bias in primary studies” was the most commonly occurring type of spin in this review; it is found in many previous studies in other orthopaedic literature, ranging from 23.1%-65%. A common weakness contributing to this type spin was drawing conclusions based on primary studies of low levels of evidence

‘‘Conclusion claims the beneficial effect of the experimental treatment despite reporting bias’’ was the next most common; which may mislead readers by the selective inclusion and omission of results in the abstract. Reporting bias results from the tendency to overreport or selectively publish positive results. One example of reporting bias can be seen in a recent article that concluded that the reverse shoulder arthroplasty “provided highly favorable results” but only reported the statistically significant improvement in Constant scores and omitted the lack of statistically significant improvements in VAS, ASES,  SST, and functional range of motion measurements. 

The 15 types of spin are listed here as a heads up for surgeons considering publishing a systematic review. 

The title claims or suggests a beneficial effect of the experimental intervention not supported by the findings 

Authors hide or do not present any conflict of interest 

Selective reporting of or overemphasis on efficacy outcomes or analysis favoring the beneficial effect of the experimental intervention 

Selective reporting of or overemphasis on harm outcomes or analysis favoring the safety of the experimental intervention 

Failure to specify the direction of the effect when it favors the control intervention 

Failure to report a wide confidence interval of estimates 

The conclusion claims the beneficial effect of the experimental treatment despite a high risk of bias in primary studies – Most common 43.8 % of the glenoid augmentation studies.

The conclusion claims the beneficial effect of the experimental treatment despite reporting bias. Second most common (37.5% of the glenoid augmentation studies.).

The conclusion formulates recommendations for clinical practice not supported by the findings 

The conclusion claims safety based on non-statistically significant results with a wide confidence interval 

The conclusion focuses selectively on statistically significant efficacy outcome 

The conclusion claims equivalence or comparable effectiveness for non-statistically significant results with a wide confidence interval 

The conclusion extrapolates the review findings to a different intervention (e.g., claiming efficacy of one specific intervention although the review covered a class of several interventions) 

Conclusion extrapolates the review's findings from a surrogate marker or a specific outcome to the global improvement of the disease 

Conclusion extrapolates the review's findings to a different population or setting 

The authors also applied A Measurement Tool to Assess Systematic Reviews (AMSTAR 2), a questionnaire that quantifies the quality of a systematic  review based on criteria such as whether authors reported presence of bias, impact of bias, the use of a predetermined protocol, funding sources, and conflicts of interest, and/or adequately characterized studies included in the review. Based on this review three (18.8%) of the studies were related as "moderate" quality and the remaining thirteen (81.3%) were rated as "low" quality. None met the criteria for "high" quality.  The elements of the AMSTAR 2 are shown below

Did the research questions and inclusion criteria for the review include the elements of PICO (Patient, Population, or Problem; Intervention; Comparison; Outcome)? 

Did the report of the review contain an explicit statement that the review methods were established before the conduct of the review, and did the report justify any significant deviations from the protocol?
Did the review authors explain their selection of the study designs for inclusion in the review?
Did the review authors use a comprehensive literature search strategy?
Did the review authors perform study selection in duplicate?
Did the review authors perform data extraction in duplicate?
Did the review authors provide a list of excluded studies and justify the exclusions?
Did the review authors describe the included studies in adequate detail?
Did the review authors use a satisfactory technique for assessing the risk of bias in individual studies that were included in the review? 

Did the review authors report on the sources of funding for the studies included in the review?

The authors also found a statistically significant association between the presence of a conflict of interest and the lack of reporting funding sources. These conflicts included examples of all of the following: authors who reported receiving grants, personal fees, royalties, and research fees from orthopedic device manufacturers, as well as authors who were investors, presenters, or consultants for orthopedic device manufacturers.

They concluded  that “Spin is highly prevalent in the abstracts of systematic reviews and meta-analyses studying glenoid augmentation with TSA. Misleading reporting is the most common category of spin.“

 

We want our publications to be as useful and as transparent as possible. Hopefully, this guide will help us avoid spin when we present our work.

Bullock's Oriole

Umtanum Washington, 5/25/25

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

Follow on twitter/X: https://x.com/RickMatsen
Follow on facebook: https://www.facebook.com/shoulder.arthritis
Follow on LinkedIn: https://www.linkedin.com/in/rick-matsen-88b1a8133/

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).

Spin and the subacromial balloon spacer for massive, irreparable rotator cuff tears.

Spin plays a major role in tennis, basketball, baseball, golf, soccer, cricket, pool, bowling, ping pong, and all other ball sports.

Spin is achieved by applying an unbalanced force to the ball, causing it to rotate in the direction desired by the player.

In publications of clinical research on innovative treatments, positive spin is a frequent form of unbalanced reporting in which beneficial claims are overemphasized while negative findings are minimized, resulting in a biased conclusion that emphasizes the value of the intervention.

The authors of Evaluation of Spin in Reviews of Biodegradable Balloon Spacers for Massive, Irreparable Rotator Cuff Tears list 12 types of spin:

Abstracts are the part of publications most commonly read by surgeons. Spin is most problematic in abstracts, given their brevity and can result in the misrepresentation of a study’s actual findings. 

These authors conducted a search in the PubMed and Embase databases using the search terms: “subacromial balloon”, “subacromial spacer”, “rotator cuff”,  “irreparable”, “systematic review”, and “meta-analysis.” 

A total of 29 studies met their inclusion criteria, of which 10 were reviews or meta-analyses and the remaining 19 were primary studies. The majority of included studies were classified as level IV evidence and only one RCT met this study’s inclusion criteria. 

Spin was highly prevalent in the abstracts of primary studies, systematic reviews, and  meta-analyses discussing the use of the subacromial balloon spacer in the treatment of massive, irreparable rotator cuff tears: spin was identified in 27 of the 29 studies ( 93.1%). Below is a list of the types of spin re-ordered by frequency of occurrence in publications on the subacromial balloon.

Spin commonly served to promote the clinical successes of balloon spacer implantation, often by overlooking confounding factors that may question the accuracy of a study’s findings as shown in the two most frequent types:

Type 3 spin, “Selective reporting of or overemphasis on efficacy outcomes or analysis favoring the beneficial effect of the experimental intervention”

Type 9 spin, “Conclusion claims the beneficial effect of the experimental treatment despite reporting bias”.

Comment:  To date, there is a lack of high-quality evidence demonstrating superiority of the subacromial balloon spacer in treating massive irreparable rotator cuff tears. Subacromial balloon spacer for irreparable rotator cuff tears of the shoulder (START:REACTS): a group-sequential, double-blind, multicentre randomised controlled trial. found that débridement alone outperformed the subacromial balloon spacer for the treatment of these tears.

Similar frequencies of spin are likely to be found in abstracts regarding most other orthopaedic interventions.

Analyzing Spin in Abstracts of Orthopaedic Randomized Controlled Trials With Statistically Insignificant Primary Endpoints found an incidence of 44%.

Evaluation of spin in systematic reviews and meta-analyses of superior capsular reconstruction found least 1 form of spin in all 17 qualifying studies. The most common types of spin were type 5 ("The conclusion claims the beneficial effect of the experimental treatment despite a high risk of bias in primary studies") and type 9 ("Conclusion claims the beneficial effect of the experimental treatment despite reporting bias"), both of which were observed in 11 studies (65%). A statistically significant association between lower level of evidence and type 5 ("The conclusion claims the beneficial effect of the experimental treatment despite a high risk of bias in primary studies") was observed. Interestingly, The Number of Surgeons Using Superior Capsular Reconstruction for Rotator Cuff Repair Is Declining

Readers, reviewers, authors and editors need to be alert to spin in reports of research and consider its presence in efforts to optimize the literature and in the interpretation of current publications, especially those concerning new technologies.

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

Follow on twitter: https://twitter.com/shoulderarth
Follow on facebook: click on this link
Follow on facebook: https://www.facebook.com/frederick.matsen
Follow on LinkedIn: https://www.linkedin.com/in/rick-matsen-88b1a8133/

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).