Two designs of primary reverse total shoulder arthroplasty (rTSA), inlay reverse total shoulder arthroplasty (in-rTSA) and onlay reverse total shoulder arthroplasty (on-rTSA) that had undergone an ...aseptic revision were compared to determine differences in the rate of rerevision.
In this comparative observational national registry study between January 1, 2012, and December 31, 2021, all rTSA utilizing either a modular inlay or onlay metaphyseal humeral component that had been revised for aseptic reasons formed 2 cohort groups. The cumulative percentage rerevision (2nd CPR) was determined using Kaplan-Meier estimates of survivorship and hazard ratios (HRs) from Cox proportional hazard models adjusted for age and sex. A minor category revision involved exchange of parts not fixed to bone whilst major revisions did. The primary and revision diagnoses, surgeon primary volume experience, and revision category were compared. Shoulder Modular Replacement (SMR)/SMR L1 or L2 combination (Lima Corporate, San Daniele del Friuli, Italy) was excluded at subanalysis.
The 2nd CPR at 3 years was 20.4% (95% confidence interval 17.1, 24.1) for in-rTSA (n = 571) and 16.1%(11.6, 22.2) for on-rTSA (n = 249). The risk of rerevision was not different between the 2 cohort groups. Primary diagnosis fracture was associated with an increased risk of rerevision for on-rTSA (entire period on-rTSA HR = 3.16(1.50, 6.68), P = .002), and in-rTSA at subanalysis (entire period on-rTSA HR = 2.91(1.33, 6.33), P = .007). 59.9% of in-rTSA and 24.1% of on-rTSA aseptic revisions were minor. The revision diagnosis, the surgical experience of rTSA and if the revision was major or minor did not change the rate of rerevision. The most common reason for both in-rTSA (50%) and (43.2%) on-rTSA rerevision was instability/dislocation.
Rerevision rates of in-rTSA and on-rTSA after aseptic revision are high. The primary rather the revision diagnosis changed rerevision rates in contemporary rTSA surgery. Minor revisions did not reduce rerevision rates for in-rTSA or on-rTSA compared to humeral/glenoid revision. Increased surgical experience of primary rTSA did not change the rate of rerevision of in-rTSA or on-rTSA.
The purpose of this study was to determine the incidence of primary reverse total shoulder arthroplasty (RTSA) and anatomic total shoulder arthroplasty (TSA) in the United States and examine changes ...in age- and sex-based procedure rates. A secondary goal was to determine the incidence of hemiarthroplasty.
Using nationally representative data along with US Census data, we identified >508,000 cases of primary RTSA, anatomic TSA, and shoulder hemiarthroplasty from 2012 to 2017. Trends in the incidence of each procedure were analyzed, and sex- and age-adjusted procedure rates were calculated.
From 2012 to 2017, the population-adjusted incidence of primary RTSA increased from 7.3 cases per 100,000 persons (22,835 procedures) to 19.3 cases per 100,000 (62,705 procedures); anatomic TSA increased from 9.5 cases per 100,000 (29,685 procedures) to 12.5 cases per 100,000 (40,665 procedures); and hemiarthroplasty decreased from 3.7 cases per 100,000 (11,695 procedures) to 1.5 cases per 100,000 (4930 procedures). These trends were observed among male and female patients, as well as all age groups. The greatest increase in incidence was seen in male patients as well as patients aged 50-64 years undergoing RTSA.
The incidence of primary RTSA and incidence of anatomic TSA have increased substantially in the United States from 2012 to 2017 whereas the incidence of hemiarthroplasty has decreased.
An understanding of the substantial clinical benefit (SCB) after total shoulder arthroplasty (TSA) may help to gauge a minimum threshold beyond which a patient perceives his or her outcome as being ...substantially better. This study quantifies SCB for 7 outcome metrics and active motion measurements after shoulder arthroplasty and determines how these values vary based on prosthesis type, patient age at surgery, sex, and length of follow-up.
A total of 1,568 shoulder arthroplasties with 2-year minimum follow-up were performed by 13 shoulder surgeons and enrolled in a multicenter registry. The SCB for the American Shoulder and Elbow Surgeons Shoulder Assessment, Constant Score, University of California Los Angeles Shoulder Rating Scale, Simple Shoulder Test, Shoulder Pain and Disability Index, global shoulder function, and visual analog scale pain scores, as well as active abduction, flexion, and external rotation were calculated for different patient cohorts using an anchor-based method.
The anchor-based SCB results were American Shoulder and Elbow Surgeons score, 31.5 ± 2.0; Constant Score, 19.1 ± 1.7; University of California Los Angeles Shoulder Rating Scale score, 12.6 ± 0.5; Simple Shoulder Test score, 3.4 ± 0.3; Shoulder Pain and Disability Index score, 45.4 ± 2.2; global shoulder function, 3.1 ± 0.2; visual analog scale, 3.2 ± 0.3; active abduction, 28.5° ± 3.1°; active forward flexion, 35.4° ± 3.5°; and active external rotation, 11.7° ± 1.9°. Anatomic TSA patients, male patients, and patients of longer follow-up duration were associated with higher SCB values than female patients, reverse TSA patients, and patients of shorter follow-up duration.
Our analysis demonstrated two-thirds of patients achieved the SCB threshold after TSA. Generally, a change of 30% of the total possible score for each outcome metric approximates or exceeds this SCB threshold.
Prior research has shown that industry funding can impact the outcomes reported in medical literature. Limited data exist on the degree of bias that industry funding may have on shoulder arthroplasty ...literature outside of the Journal of Shoulder and Elbow Surgery. The purpose of this study is to characterize the type and frequency of funding for recently published shoulder arthroplasty studies and the impact of industry funding on reported outcomes. We hypothesized that studies with industry funding are more likely to report positive outcomes than those without.
We performed a retrospective study searching all articles with the term “shoulder arthroplasty,” “reverse shoulder arthroplasty,” “anatomic total shoulder arthroplasty,” or “total shoulder arthroplasty” on PubMed from the years January 2020 to December 2022. The primary outcome of studies was coded as either positive, negative, or neutral. A positive result was defined as one in which the null hypothesis was rejected. A negative result was defined as one in which the result did not favor the group in which the industry-funded implant was used. A neutral result was defined as one in which the null hypothesis was confirmed. Article funding type, subcategorized as National Institutes of Health funding or industry funding was recorded. Author disclosures were recorded to determine conflicts of interest. Statistical analysis was conducted using the χ2 test and Fisher exact test.
A total of 750 articles reported on either conflict of interest or funding source and were included in the study. Of the total number of industry-funded studies, the majority were found to have a positive primary endpoint (58.1%, 104 of 179), as compared to a negative (7.8%, 14 of 179) or neutral endpoint (33.5%, 60 of 179) (P = .004). Overall, 363 articles reported an author conflict of interest, and the majority of these studies had positive primary endpoint (55.6%, 202 of 363) as compared to negative (9.1%, 33 of 363) or neutral endpoints (34.4%, 125 of 363) (P = .002).
The results of this study suggest that there is a significant relationship between conflicts of interest and the primary outcome of shoulder arthroplasty studies, beyond the overall positive publication bias. Studies with industry funding and author conflicts of interest both report positive outcomes more frequently than negative outcomes. Shoulder surgeons should be aware of this potential bias when choosing to base clinical practice on published data.
Purpose of Review
The most common complications warranting revision consideration in reverse shoulder arthroplasty (RSA) include instability and its associated causes: infection, periprosthetic ...fracture, and glenoid baseplate loosening. Management of complications can be challenging and the nuances of treatment are still being elucidated. The focus of this paper is to review the treatment of the failed RSA and discuss evidence-based recommendations for revision.
Recent Findings
The most common complications requiring revision RSA are instability and infection. The causes for instability can be subdivided into three main subcategories: loss of compression, loss of containment, and impingement. Loss of compression is further broken down into 6 subcategories revolving around abnormal prosthesis positioning, undersized prostheses, or intrinsic soft-tissue tension loss leading to instability. Periprosthetic infection can also lead to instability, yet the most appropriate management for infected RSA remains controversial.
Summary
Restoring stability by maximizing deltoid and soft tissue tension while avoiding impingement revolves around three basic methods: (1) lateralizing and/or upsizing the glenosphere to an inferior position on the glenoid, (2) use of a more constrained polyethylene insert, and (3) distalizing the humerus by increasing the polyethylene thickness and/or the thickness of the humeral tray. Management of periprosthetic joint infection can be performed in one-stage, two-stage, or “three-stage” procedures all showing good outcomes with two-stage procedures being the most commonly performed. However, persistent positive culture with propriobacterium acnes can occur in up to 25% of cases. In order to limit the associated morbidity from failed revision reverse shoulder arthroplasty, continued research on best management of associated complications is warranted.
As the incidence of shoulder arthroplasty continues to rise, encountering significant glenoid bone loss in the primary and revision setting is becoming a common occurrence. To effectively treat these ...difficult scenarios, surgeons must understand the common patterns of glenoid bone loss and be aware of the various techniques available for treatment. Understanding bone loss requires careful pre-operative evaluation with appropriate imaging and pre-operative planning software. Treatment algorithms consist of primary anatomic and reverse arthroplasty as well as the use of allograft or autograft bone grafting, augmented glenoid components, specialized surgical techniques, or custom implant designs. Ultimately, good outcomes are able to be obtained with various techniques when applied to the appropriate clinical situation.
Contemporary studies note sustained clinical benefit and decreasing complications after reverse total shoulder arthroplasty (RTSA), which warrant a comparison with the standard anatomic total ...shoulder arthroplasty (ATSA). The purpose of this study is to evaluate and compare differences in midterm survivorship between ATSA and RTSA patients treated with a single platform shoulder prosthesis. Secondary objectives include a comparison of the clinical outcomes and complication profile for each procedure.
A prospective analysis of all primary ATSA and RTSA performed by 3 surgeons between 2007 and 2012 was conducted. Selection of the ATSA or RTSA implant configuration was determined by the surgeons per their clinical understanding of each individual patient's glenoid morphology, rotator cuff, and patient expectations. All 778 procedures were performed using a single platform shoulder system.
Survivorship for ATSA was similar to that for RTSA at all time points; ATSA at 2 and 8 years was 98.5% and 96.0%, whereas RTSA at 2 and 8 years was 98.7% and 96.0%, respectively ( P= .392). All postoperative range of motion scores for ATSA patients were greater than those for RTSA patients. The overall rate of complications between the ATSA and RTSA groups was similar (6.3% vs. 4.9%, P= .414).
On the basis of this cohort comparison, both ATSA and RTSA demonstrated similar survivorship at 8 years after surgery with multiple surgeons practicing in different countries. Our results demonstrate that the RTSA and ATSA implants have comparable results and can be expected to provide similar implant longevity over the midterm with excellent functional outcomes.
It is common for patients to require staged bilateral shoulder arthroplasties. There is a unique cohort of patients who require an anatomic total shoulder arthroplasty (TSA) and a contralateral ...reverse shoulder arthroplasty (RSA). This study compared the outcomes of patients with a TSA in 1 shoulder and an RSA in the contralateral shoulder.
Our institutional database was queried to identify all patients with a TSA and a contralateral RSA. Data collection included patient demographics, preoperative and latest follow-up shoulder range of motion, radiographic analysis, and postoperative complications. Identified patients were assessed at follow-up visits or contacted by phone for functional outcome scores.
Nineteen patients met our inclusion/exclusion criteria. There was statistically significant greater internal rotation in the TSA shoulder (P = .044) but no significant difference in forward elevation (P = .573) or external rotation (P = .368). There was no radiographic evidence of humeral or glenoid component loosening of any arthroplasty implants. There were no significant differences between TSA and RSA shoulders for the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment (P = .381), Simple Shoulder Test (P = .352), Single Assessment Numerical Evaluation (P = .709), and visual analog scale satisfaction (P = .448) or pain scores (P = .305). Thirteen patients (68.4%) preferred the RSA side, 1 patient (5.3%; z = 4.04, P < .001) patient preferred the TSA side, and 5 patients expressed no preference.
Despite known limitations and differences between TSA and RSA designs, patients who have received both implants are highly satisfied with both. The only parameter in which the TSA had superior outcomes was internal rotation.
Knowledge of the minimal clinically important difference (MCID) for different shoulder outcome metrics and range of motion after total shoulder arthroplasty (TSA) can be useful to establish a minimum ...threshold of improvement that defines successful treatment. This study quantifies how MCID varies with different prosthesis types, patient age, gender, and length of follow-up after TSA.
A total of 466 anatomic TSA (aTSA) and reverse TSA (rTSA) with 2-year minimum follow-up were performed by 13 shoulder surgeons. The MCID for the American Shoulder and Elbow Surgeons, Constant, University of California Los Angeles Shoulder Rating Scale, Simple Shoulder Test, Shoulder Pain and Disability Index, global shoulder function, and visual analog scale for pain scores, as well as active abduction, forward flexion, and external rotation, were calculated for different prosthesis types and patient cohorts using an anchor-based method.
The anchor-based MCID results were American Shoulder and Elbow Surgeons = 13.6 ± 2.3, Constant score = 5.7 ± 1.9, University of California Los Angeles Shoulder Rating Scale = 8.7 ± 0.6, Simple Shoulder Test score = 1.5 ± 0.3, Shoulder Pain and Disability Index score = 20.6 ± 2.6, global shoulder function = 1.4 ± 0.3, pain visual analog scale = 1.6 ± 0.3, active abduction = 7° ± 4°, active forward flexion = 12° ± 4°, and active external rotation = 3° ± 2°. Female gender and rTSA were associated with lower MCID values compared with male gender and aTSA patients.
The minimum improvement necessary for patients to achieve a result they believe is clinically meaningful after aTSA and rTSA is nominal and was achieved by at least 80% of the patients. Future endeavors should investigate the influence of different anchor questions on the MCID calculation.
Stemless shoulder arthroplasty was originally introduced in 2004 by a single manufacturer. Now, over a decade later, numerous designs are available outside the USA, but as yet, only one implant has ...been cleared by the Food and Drug Administration (FDA) and is available for use within the USA. Often referred to as “canal sparing,” these implants are designed for metaphyseal fixation to minimize humeral bone removal, avoid intraoperative and postoperative humeral fracture complications, and to decrease morbidity associated with revision operations. Recently, the second generation of stemless arthroplasty, a convertible implant allowing use in either anatomic or reverse arthroplasty configuration, was released for use outside the USA. This paper will review the available designs, reported results, and raise potential concerns for this emerging technology.