Skip to main content
NCBI home page
JSES International logoLink to JSES International
. 2025 Jul 1;9(6):2037–2043. doi: 10.1016/j.jseint.2025.06.004

Smaller glenosphere size and increased baseplate retroversion improve postoperative internal rotation after reverse total shoulder arthroplasty performed with a 135° humeral implant and lateralized glenoid

Joseph Adams a, Samer Al-Humadi b, Brian C Werner c, Philipp Moroder d, Patric Raiss e, Asheesh Bedi f, Evan Lederman g, Justin Griffin h; Shoulder Arthroplasty Research Committee (ShARC) Group1, Patrick J Denard b,∗
PMCID: PMC12828197  PMID: 41584530

Abstract

Background

Optimal placement of the glenosphere in reverse shoulder arthroplasty (rTSA) is a key component affecting postoperative range of motion (ROM) but remains a subject of ongoing research. The purpose of this study was to evaluate the relationship between three-dimensional (3D) glenosphere position and orientation relative to anatomic scapular landmarks and postoperative patient-reported outcomes and ROM following rTSA.

Methods

A retrospective multicenter cohort study was conducted on primary rTSAs performed with a 135° humeral inlay component and a lateralized glenoid component between November 2016 and March 2022. Surgeries performed with a 3D plan and patient-specific transfer instrumentation with minimum 2-year clinical follow-up were included. Implant position was extracted from preoperative planning software, focusing on pin position (center of the glenosphere) and glenosphere diameter, version, and overhang relative to scapular anatomic landmarks. ROM and American Shoulder and Elbow Surgeons (ASES) scores were assessed at 2-year follow-up, with linear regression models utilized to analyze the relationships between preoperative and intraoperative variables and postoperative outcomes while adjusting for confounding variables.

Results

A total of 75 rTSAs met the study criteria. For every 1 millimeter increase in glenosphere diameter, there was a 0.5 spinal level decrease in internal rotation (IR) spine (P ≤ .005) and a 2.5° decrease in forward flexion (P ≤ .005). For every 4° increase in baseplate retroversion, there was a 1 spinal level improvement in IR spine (P = .009). Superior tilt of the baseplate was associated with a decrease in internal rotation at 90° of abduction (3° decrease per 1° of increased superior tilt, P ≤ .001). ASES scores were also significantly affected, with a 3.5 point decrease per millimeter increase in glenosphere diameter (P ≤ .001), but improved by a 1 point per millimeter increase in pin-to-coracoid distance (P = .015).

Conclusion

In patients with 3D planning and patient-specific instrumentation, smaller glenosphere diameter, increased baseplate retroversion, and avoidance of superior tilt improve IR after rTSA performed with a 135° humeral component and lateralized glenoid. A smaller glenosphere diameter and increased distance from the coracoid also improved ASES scores. This data suggests that with the use of a lateralized glenoid in rTSA, efforts should be made to increase the glenosphere distance from the coracoid, avoid a superior tilted positioning of the baseplate, and consider a smaller glenosphere when in between sizes.

Keywords: Reverse shoulder arthroplasty, Preoperative planning software, Glenosphere positioning, Postoperative outcomes, Baseplate retroversion, 3D software, Humeral inlay component, Patient reported outcomes

Reverse shoulder arthroplasty (rTSA) is a well-established surgical intervention in the management of various shoulder pathologies, ranging from rotator cuff arthropathy to complex fractures or severe glenohumeral arthritis.16,35 Despite advancements in surgical technique, challenges still exist in achieving optimal function after an rTSA, with the precise placement of the glenosphere component as a crucial factor in influencing postoperative range of motion (ROM) and overall patient satisfaction.2,6,11,19,30,37

Current literature highlights the importance of preoperative planning with rTSA cases, suggesting detailed assessments of patient-specific anatomy can positively impact surgical outcomes.27,28 Advances in three-dimensional (3D) imaging and preoperative planning software have offered surgeons the ability to tailor surgical approaches and prosthetic selection to improve outcomes.9,32 Many virtual 3D studies have suggested lateralizing the glenosphere in rTSA to reduce bony impingement and thus improve ROM. However, the few existing clinical studies have primarily utilized plain radiographs, and thus lack the ability to define the position of the glenosphere in multiple planes or accurately assess the relationship between the glenosphere and the coracoid process.8,21,38

The purpose of this study was to evaluate the relationship between 3D glenosphere position and orientation using preoperative templating software relative to anatomic scapular landmarks and postoperative patient-reported outcomes and ROM following rTSA. We hypothesized that increased axial and sagittal distances of the center of the glenosphere from the coracoid would be associated with improved ROM.

Materials and methods

Study design and population

A retrospective study was conducted on a prospectively maintained database from multiple centers. The study included patients who underwent primary rTSA between November 2016 and March 2022 with a minimum follow-up period of two years postoperatively.

Inclusion and exclusion crteria

Patients met the criteria for inclusion if the surgeon utilized preoperative planning software (Virtual Implant Positioning; Arthrex, Inc., Naples, FL) and the patient underwent a primary rTSA using a 135° humeral inlay component with patient-specific transfer instrumentation. Exclusion criteria were lack of 3D preoperative planning, revision procedures, acute or prior fractures, and incomplete postoperative follow-up data.

Preoperative planning and surgical technique

Detailed measurements were retrospectively extracted from the 3D preoperative plans to assess intended glenosphere placement (Figure 1, Figure 2, Figure 3). The center of the glenosphere was defined as the planned glenoid pin position in the 3D imaging software. The following eight measurements were recorded: 1) native inclination, 2) native version, 3) implant inclination, 4) glenoid pin to posterior acromion in the sagittal plane, 5) glenoid pin to anterior acromion in the sagittal plane, 6) glenoid pin to lateral coracoid in the sagittal plane, 7) glenosphere overhang in the sagittal plane (anterior, inferior, and posterior), and 8) glenosphere diameter.

Figure 1.

Figure 1

Open in a new tab

Center of rotation to acromial distances. The center of rotation was measured on scapular Y radiographs. A best-fit circle was made on the glenosphere and the center was marked. From there, three measurements were made: Center of rotation to coracoid (CC), Center of rotation to anterior acromion (CAA), and Center of rotation to posterior acromion (CPA).

Figure 2.

Figure 2

Open in a new tab

Glenoid height and width. The center of rotation was measured on scapular Y radiographs. A best-fit circle was made on the glenosphere and the center was marked. The superior and inferior aspects of the glenoid were marked and a line was drawn through the Center of rotation (COR) to determine the glenoid height (GH). A second line was drawn perpendicular to the glenoid height (GH) through the COR to determine the glenoid width (GW).

Figure 3.

Figure 3

Open in a new tab

Glenosphere overhang. The center of rotation was measured on scapular Y radiographs. A perfect-circle was made on the glenosphere and the center was marked. From there, three measurements were made: anterior glenoid to anterior glenosphere (A), posterior glenoid to posterior glenosphere (P), and inferior glenoid to inferior glenospehere (I).

Surgeries were performed by seven surgeons. Baseplate position, glenosphere offset, and glenosphere size were based on surgeon preference. In all surgeries, a deltopectoral approach was used with a 135° inlay humeral component (Univers Revers; Arthrex, Inc., Naples, FL, USA). For the glenoid, an anatomically shaped baseplate was used prior to 2018 (Universal Baseplate; Arthrex, Inc.) and a modular circular baseplate (Modular Glenoid System; Arthrex, Inc., Naples, FL, USA) was used from 2018 through 2021. Glenoid-sided lateralization occurred through the baseplate and/or glenosphere and varied from 0 to 8 mm in 2 mm increments. Glenospheres with diameters ranging from 33 mm to 42 mm were utilized. All glenoid components were placed with a clinically validated reusable patient-specific guide. This guide (5D Targeter; Arthrex Inc., Naples, FL, USA) has 5 adjustable legs to translate the preoperative plan into implementation. If there was a difference between planned glenosphere size and implanted glenosphere size, the actual glenosphere diameter was subtracted from the planned diameter. The radius difference between planned and implanted glenosphere was added to each of the overhang measurements. For example, if a 36 glenosphere was planned but a 39 glenosphere was implanted, 1.5 mm was added to the anterior, inferior, and posterior overhang measurements.

Data collection and analysis

Data on patient characteristics, demographics, surgical details, and follow-up examination results were extracted from the database and analyzed. Two-year postoperative active ROM was assessed at each site per surgeon preference with a goniometer used to assess internal rotation at 90° of abduction (IR90) and external rotation at 90° of abduction (ER90), forward flexion (FF), and external rotation with the arm at the side (ER0). Internal rotation (IR) behind the back was estimated to the nearest spinal level (IR spine). American Shoulder and Elbow Surgeons (ASES) scores were also collected as part of the functional outcome assessment.22

Linear regression models were developed to examine the relationship between preoperative planning variables and postoperative outcomes, adjusting for the following potential confounding variables: sex, age, arm dominance, body mass index, tobacco use, diabetes, whether the subscapularis was repaired, metallic glenoid lateralization, and the baseline of the clinical outcome measure that was being assessed in the particular regression. The statistical significance was set at P ≤ .05.

Results

A total of 75 patients met the study criteria with a mean age of 70 years and a standard deviation of approximately 7.8 years. The mean follow-up after surgery was 2.2 years (range 2.0-3.3 years). Clinical outcomes for ASES score, forward elevation, IR at spinal level, external rotation (ER) at side, IR at 90 degrees, and ER at 90 degrees of the cohort are summarized in Table I.

Table I.

Comparison of preoperative and postoperative outcomes.

Measurement Preoperative Postoperative P value
ASES score (mean ± SD) 43.2 ± 18.2 83.6 ± 16.4 <.001
Forward elevation (mean ± SD) 102.6° ± 46.8 145.7° ± 28.7 <.001
IR at spinal level L5 L4 .102
ER at side (mean ± SD) 28.9° ± 22.4 49° ± 17.6 <.001
IR at 90 degrees (mean ± SD) 10.7° ± 21.9 17.5° ± 22 .067
ER at 90 degrees (mean ± SD) 9.5° ± 22.4 52.1° ± 31.2 <.001
Open in a new tab

ASES, American Shoulder and Elbow Surgeons; IR, internal rotation; ER, external rotation; SD, standard deviation.

Glenosphere diameter

Increased glenosphere diameter was associated with decreased IR spine, with every 1 mm increase resulting in a 0.5 spinal level reduction in IR spine at the 2-year follow-up (P ≤ .005). Each 1 mm increase in glenosphere diameter was associated with a 3.5-point decline in ASES scores (P ≤ .001). In addition, each 1 mm increase in glenosphere diameter was associated with a 2.5° decrease in FF (P ≤ .005) (Table II).

Table II.

Effects of glenosphere diameter, tilt, and overhang on outcomes.

Measurement Outcome variable Effect Statistical significance
IR spine Glenosphere diameter Every 1 mm increase → 0.5 spinal level reduction P = .023
IR spine Baseplate retroversion Every 4° increase → 1 spinal level improvement P = .009
IR spine Anterior glenoid overhang Every 1 mm increase → 1 spinal level worsening P = .004
IR90 Superior tilt Each 1° increase → 3° reduction P = .008
IR90 Anterior glenosphere overhang 1 mm increase → 7° reduction P ≤ .001
IR90 Inferior glenoid overhang 1 mm increase → 6° reduction P ≤ .001
FF Glenosphere diameter 1 mm increase → 2.5° decrease P = .040
FF Superior tilt Each 1° increase → 4° decrease P ≤ .001
Open in a new tab

IR, internal rotation; IR90, internal rotation at 90° of abduction; FF, forward flexion.

Baseplate orientation

Increased baseplate retroversion by 4° correlated with significant improvement in IR spine at the same interval (P = .009). Increased superior tilt was correlated with decreased IR90, with each degree of added superior tilt leading to a 3° reduction in IR90 at two years postoperatively (P ≤ .001). In addition, every degree of increased superior tilt correlated with a 4-degree decrease in FF (P ≤ .005) (Table II).

Scapular landmarks

An increase in anterior glenoid overhang was linked to a reduction in IR spine (P ≤ .005). Anterior glenosphere overhang had the greatest effect on IR90, with a 1 mm increase in anterior glenosphere overhang resulting in a 7° reduction in IR90 at two years postoperatively (P ≤ .001). Similarly, a 1 mm increase in inferior glenoid overhang corresponded to a 6° decline in IR90 at the 2-year follow-up (P ≤ .001) (Table II).

Glenoid center measurements

A 1 mm increase in the glenoid pin to coracoid distance was correlated with a 1-point increase in ASES scores (P = .015). No significant findings were observed with the pin to posterior acromion and pin to anterior acromion distances.

Discussion

The most important findings of the current study were that increasing distance of the glenosphere from the coracoid, increased retroversion, and decreased glenosphere diameter improved ROM and postoperative ASES scores following rTSA. By analyzing the impact of glenosphere diameter, baseplate retroversion, and glenoid overhang, our research contributes to a growing body of evidence that emphasizes preoperative planning for rTSA directly corresponds with patient satisfaction and rTSA survivorship.10,31,33 These findings may have implications for optimizing patient outcomes after rTSA, particularly in enhancing functional outcomes and ROM.

The significant association between increased glenosphere diameter and decreased ROM, as well as lower ASES scores, emphasizes the importance of accurately matching the glenosphere size to the patient's anatomy. This finding aligns with previous research suggesting that an oversized glenosphere may lead to bony impingement and restricted movement due to altered biomechanics of the shoulder following rTSA.17,23 The present study reinforces the need for careful consideration of glenosphere size during preoperative planning to avoid compromising shoulder function. In addition, assuming adequate soft tissue tension (ie, lateralization) when selecting glenosphere sizes, our findings suggest opting for the lower size if a patient is between sizes to minimize the risk of decreased ROM and lower ASES scores. Future research into soft tissue tension and optimizing Blix curve for the deltoid may help to further refine this algorithm for a glenosphere selection that improves overall shoulder function without increasing the risk of dislocation.15,26

Interestingly, the findings of the present investigation suggest that increased baseplate retroversion is beneficial for improving shoulder IR. Prior studies have not shown an impact of retroversion on IR. Jawa et al evaluated 271 rTSA patients and observed no significant differences in postoperative ROM of functional outcomes between patients with baseplate retroversion less than 15° and those with retroversion greater than 15°.3 However, they only measured retroversion on plain radiographs and did not analyze its effect on IR. In our study, retroversion was based on 3D analysis and all surgeries were executed with patient-specific instrumentation. We observed significant improvement in IR with increased retroversion suggesting that slight alterations in the orientation of the baseplate can significantly affect the clearance for IR. This finding is particularly relevant for surgical techniques aiming to maximize postoperative IR without compromising stability or risking impingement, therefore offering patients a greater degree of function after surgery. However, some studies suggest that retroversion compromises active ER; thus more research is needed to understand the optimal balance of retroversion to ensure the best overall shoulder function.1,5,12 In addition, increased retroversion may increase surgical complexity due to the orientation of the glenoid and the ability to intentionally retrovert the baseplate may be limited by exposure and surgical skill.

The findings further indicate that excessive anterior overhang can detrimentally affect IR.13,34 Lee et al demonstrated similar results on biomechanical cadaveric testing, indicating that excessive anterior positioning of the glenosphere may inhibit IR due to altered shoulder mechanics.18 Our study, utilizing 3D analysis, further supports these findings by showing a significant reduction in IR with increased anterior glenoid overhang. Anterior glenosphere overhang had the largest impact on IR90 with every 1 mm of overhang decreasing IR90 by 7°. This delicate balance between stability and mobility must be navigated carefully in rTSA planning, emphasizing the need for tailored approaches based on individual anatomical variation. Additional research is necessary to determine the optimal balance between anterior stability and IR to optimize overall shoulder function after rTSA.25

In addition to improvement in ROM, increasing the glenoid pin to coracoid distance was significantly associated with improved patient-reported outcomes as measured by ASES scores in the current study. Prior studies primarily relying on plain radiographs and clinical assessments also support that optimizing the distance between the glenoid center and anatomical landmarks like the coracoid can lead to better ROM and reduced pain postoperatively.14,24 In combination with our findings, this suggests that optimizing the glenoid implant center to coracoid distance during preoperative planning could enhance functional outcomes. However, it should be noted the magnitude of change in ASES scores did not exceed the minimal clinically important difference, with a 1 mm increase only improving the ASES score by 1 point.22

While this study provides valuable insight that careful glenosphere sizing and positioning with preoperative templating may affect postoperative outcomes, it is not without limitations. First, patient glenoid anatomy varies and incremental changes are relative between each case. The reliance on a single preoperative planning software may restrict the generalizability of the findings.36 The accuracy of the 3D models should also be taken into consideration; however, it is important to note the specific software utilized in the present study has established reliability in reproducing the complexity of the individual patient anatomy.7 Nevertheless, variations in software performance may exist, potentially leading to discrepancies between the preoperative plan and intraoperative reality.29 Rodriguez et al showed while 3D preoperative planning software is beneficial, it does not always translate perfectly into intraoperative execution due to the dynamic nature of surgery and individual anatomical variations that are difficult to account for preoperatively.7,8 In contrast, Lilley et al discussed variability in preoperative planning outcomes based on the differing software systems and the varying tools used.20 Lastly, we did not have postoperative computed tomography scans to confirm postoperative position. Although transfer technology from preoperative plan to implantation has been validated, it is possible that there were small deviations from the plan to postoperative position. While discrepancies are unavoidable with complex and imperfect technology, the use of preoperative planning software has consistently proven itself as a reliable tool to improve rTSA outcomes and patient satisfaction.4

Conclusion

In patients with 3D planning and patient-specific instrumentation, smaller glenosphere diameter, increased baseplate retroversion, and avoidance of superior tilt improve IR after rTSA performed with a 135° humeral component and lateralized glenoid. A smaller glenosphere diameter and increased distance from the coracoid also improved ASES scores; however, this did not achieve minimal clinically important difference. This data suggests that with the use of a lateralized glenoid in rTSA, efforts should be made to increase the glenosphere distance from the coracoid.

Disclaimers:

Funding: This study was supported by a grant from Arthrex, Inc.

Conflicts of interest: Dr. Brian C Werner, MD reports Arthrex: research funding, paid speaker and paid consultant; Zimmer Biomet: research funding; Exatech: research funding; and Pacira: research funding; Lifenet Health: paid consultant. Dr. Patrick J Denard, MD reports Arthrex: royalties, paid consultant, and paid speaker; PT Genie: stock ownership; Kaliber Labs: stock ownership. Dr. Albert Lin reports AAOS: Board or committee member; American Orthopaedic Association: Board or committee member; American Orthopaedic Society for Sports Medicine: Board or committee member; American Shoulder and Elbow Surgeons: Board or committee member; Annals in Joint: Editorial or governing board; Arthrex, Inc. Paid consultant; Arthroscopy: Editorial or governing board; International Society of Arthroscopy, Knee Surgery, and Orthopaedic Sports Medicine: Board or committee member; Knee Surgery, Sports Traumatology, Arthroscopy: Editorial or governing board; Tornier: Paid consultant. Dr. Anthony Romeo reports Arthrex, Inc.: Royalties, paid presenter, paid consultant; Editorial or governing board: Orthopedics Today, Orthopedics, SAGE, SLACK Incorporated, Wolters Kluwer Health; Stock or stock options: Paragen Technologies; Vertex: Research support; Royalties, Financial or Material Support from Publishers: Aunders/Mosby-Elsevier. Dr. Anup Shah reports Arthrex, Inc.: Education/research consultant; Medacta: Royalties. Dr. Asheesh Bedi reports Arthrex, Inc.: Consultant and royalties. Dr. Benjamin W. Sears reports– United Orthopaedic Corporation: consultant and royalties; Aeuvumed: consultant and royalties; Shoulder Innovations: consultant and royalties; BioPoly: consultant and royalties; Arthrex, Inc.: research funding/support; Exactech: research funding/support; Stryker: research funding/support; FX Solutions: research funding/support. Dr. Bradford Parsons reports Arthrex, Inc.: consultant and royalties; JBJS reviews: editor. Dr. Brandon Erickson reports AAOS: board or committee member; American Orthopaedic Society for Sports Medicine: board or committee member; American Shoulder and Elbow Surgeons: board or committee member; Arthrex, Inc.: paid consultant, research support; DePuy, A Johnson & Johnson Company: research support; Linvatec: research support; PLOS One: editorial or governing board; Smith & Nephew: research support; Stryker: research support. Dr. Bruce Miller reports AJSM: editorial or governing board; Arthrex, Inc.: paid consultant; FH Orthopedics: royalties. Dr. Christopher O'Grady reports Arthrex, Inc.: education consultant/Speaker; Stryker: education consultant/Speaker; Smith and Nephew: education consultant/Speaker; Mitek: education consultant/Speaker. Dr. Daniel Davis reports Arthrex, Inc.: paid consultant, paid presenter/speaker; Catalyst OrthoScience: stock or stock options; Pennsylvania Orthopaedic Society: board member; Philadelphia Orthopaedic Society: board member. Dr. David Lutton reports Arthrex, Inc.: paid consultant, paid speaker or presenter; Avanos: paid speaker or presenter; CORE: reviewer (not editor). Dr. Dirk Petre reports Arthrex, Inc.: paid consultant, paid presenter/speaker, research support. Dr. Evan Lederman reports Arthrex, Inc.: consultant, royalties, and research support. Dr. Justin Griffin reports Arthrex, Inc.: research support, royalties, paid speaker; Springer: publishing royalties. Dr. John Tokish reports Arthrex, Inc.: IP royalties, paid consultant, paid presenter or speaker; Arthroscopy Association of North America: board or committee member; Journal of Shoulder and Elbow Surgery: editorial or governing board, financial or material support; Orthopedics Today: editorial or governing board. Dr. Jorn Steinbeck reports Journal of Shoulder and Elbow Surgery: reviewer; Journal of Bone and Joint Surgery: reviewer; Arthrex, Inc.: consultant. Dr. Julia Lee reports the following Arthrex, Inc.: Consulting and medical education; American Shoulder Elbow Surgeons: committee member Dr. Kevin Farmer reports American Orthopaedic Society for Sports Medicine Florida Orthopaedic Society: board or committee member; Arthrex, Inc.: Paid consultant, paid presenter or speaker; Exactech, Inc.: paid consultant. Dr. Mathew Provencher reports Arthrex, Inc.: royalties; Arthrosurface: royalties; Responsive Arthroscopy (2020): royalties; and Anika Therapeutics, Inc.: royalties; Arthrex, Inc.: consulting fees; Joint Restoration Foundation (JRF): consulting fees; Zimmer Biomet Holdings: consulting fees; Arthrosurface: consulting fees; Department of Defense (DoD): grants; the National Institute of Health (NIH): grants; DJO (2020): grants; Flexion Therapeutics: honoria; SLACK, Inc.; editorial board or governing board member; American Association of Nurse Anesthesiology: board or committee member; American Academy of Orthopaedic Surgeons: board or committee member; American Orthopaedic Society for Sports Medicine: board or committee member; American Shoulder and Elbow Surgeons: board or committee member; SDSI: board or committee member; and SOMOs: board or committee member: Musculoskeletal Transplant Foundation: medical board of trustees (through 2018). Dr. Michael Bercik reports American Shoulder and Elbow Surgeons: board or committee member; Arthrex, Inc.: paid consultant; WRS Specialists: paid consultant. Dr. Michael Kissenberth reports Arthrex, Inc.: paid consultant; Hawkins Foundation: financial or material support; Hawkins Foundation: board member. Dr. Patric Raiss reports Arthrex, Inc.: paid consultant; Zurimed Technologies AG: shareholder. Dr. Peter Habermeyer reports Arthrex, Inc.: Royalties. Dr. Philipp Moroder reports Alyve Medical: consultant, royalties; Arthrex: consultant, royalties; Medacta: consultant, royalties. Dr. Robert Creighton reports American Board of Orthopaedic Surgery, Inc.: board or committee member; American Orthopaedic Society for Sports Medicine: board or committee member; American Shoulder and Elbow Surgeons: board or committee member; Arthrex, Inc.: paid presenter or speaker, research support, other financial or material support; Breg: other financial or material support; Johnson & Johnson: other financial or material support; Orthopedics Today: editorial or governing board; SLACK Incorporated: editorial or governing board; Smith & Nephew: other financial or material support. Dr. G. Russell Huffman reports Arthrex, Inc.: speakers bureau/paid presentations, paid consultat; LIMA: speakers bureau/paid presentations, paid consultant; Catalyst: stock or stock options; PI: LIMA IDE: research support. Dr. Samuel Harmsen reports Arthrex, Inc.: royalties, paid consultant, paid presenter or speaker, research support; Embody, Inc.: royalties, paid consultant; Enovis, Inc.: paid consultant, paid presenterl; Genesis Software Innovations, LLC: royalties, stock or stock options; Shoulder Innovations, Inc.: royalties, paid consultant, paid presenter or speaker; Zimmer US Inc.: paid consultant, paid presenter or speaker, stock or stock options. Dr. Sven Lichtenberg reports Archives of Orthopaedic and Trauma Surgery: editorial or governing board; Arthrex, Inc.: IP royalties, paid consultant, paid presenter or speaker; Exactech, Inc.: paid consultant, paid presenter or speaker; Journals of Shoulder and Elbow Surgery: editorial or governing board; Knee Surgery, Sports Traumatology, Arthroscopy: editorial or governing board. Dr. Tim Lenters reports Arthrex, Inc.: paid consultant; Irispet: research support; American Academy of Orthopaedic Surgeons: social media committee. Dr. Matthew Tyrrell Burrus reports Arthrex, Inc.: paid consultant, paid presenter or speaker, research support; Arthroscopy: editorial or governing board. Dr. Tyler Brolin reports American Academy of Orthopaedic Surgeons: board or committee member; American Shoulder and Elbow Surgeons: board or committee member; Arthrex, Inc.: IP royalties, paid consultant, research support; Elsevier: publishing royalties, financial or material support; Orthofix, Inc.: research support; Orthopedic Clinics of North America: editorial or governing board; Zimmer: research support. The other authors, their immediate families, and any research foundation with which they are affiliated have not received any financial payments or other benefits from any commercial entity related to the subject of this article.

Footnotes

The Southern Oregon Institutional Review Board chaired by Michael S. Narus, DO, approved this study.

Contributor Information

Patrick J. Denard, Email: pjdenard@gmail.com.

Shoulder Arthroplasty Research Committee (ShARC) Group:

Albert Lin, Anthony Romeo, Anup Shah, Benjamin W. Sears, Bradford Parsons, Brandon Erickson, Bruce Miller, Christopher O'Grady, Daniel Davis, David Lutton, Dirk Petre, Joern Steinbeck, John Tokish, Julia Lee, Kevin Farmer, Matthew Provencher, Michael Bercik, Michael Kissenberth, Peter Habermeyer, Robert Creighton, Russell Huffman, Sam Harmsen, Sven Lichtenberg, Tim Lenters, Tyrrell Burrus, and Tyler Brolin

References

  • 1.Berhouet J., Jacquot A., Walch G., Deransart P., Favard L., Gauci M.O. Preoperative planning of baseplate position in reverse shoulder arthroplasty: still no consensus on lateralization, version and inclination. Orthop Traumatol Surg Res. 2022;108 doi: 10.1016/j.otsr.2021.103115. [DOI] [PubMed] [Google Scholar]
  • 2.Chae S.W., Lee J., Han S.H., Kim S.-Y. Inferior tilt fixation of the glenoid component in reverse total shoulder arthroplasty: a biomechanical study. Orthop Traumatol Surg Res. 2015;101:421–425. doi: 10.1016/j.otsr.2015.03.009. [DOI] [PubMed] [Google Scholar]
  • 3.Elmallah R., Swanson D., Le K., Kirsch J., Jawa A. Baseplate retroversion does not affect postoperative outcomes after reverse shoulder arthroplasty. J Shoulder Elbow Surg. 2022;31:2082–2088. doi: 10.1016/j.jse.2022.02.043. [DOI] [PubMed] [Google Scholar]
  • 4.Fourneau T., van Haute E., De Wilde L., van Tongel A., van der Bracht H. 3D preoperative planning for shoulder arthroplasty: an evaluation of different planning software systems. Semin Arthroplasty. 2022;32:474–481. doi: 10.1053/j.sart.2022.01.006. [DOI] [Google Scholar]
  • 5.Gruber M.D., Kirloskar K.M., Werner B.C., Lädermann A., Denard P.J. Factors associated with internal rotation after reverse shoulder arthroplasty: a narrative review. JSES Rev Rep Tech. 2022;2:117–124. doi: 10.1016/j.xrrt.2021.12.007. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 6.Gutiérrez S., Walker M., Willis M., Pupello D.R., Frankle M.A. Effects of tilt and glenosphere eccentricity on baseplate/bone interface forces in a computational model, validated by a mechanical model, of reverse shoulder arthroplasty. J Shoulder Elbow Surg. 2011;20:732–739. doi: 10.1016/j.jse.2010.10.035. [DOI] [PubMed] [Google Scholar]
  • 7.Hartzler R.U., Denard P.J., Griffin J.W., Werner B.C., Romeo A.A. Surgeon acceptance of an initial 3D glenoid preoperative plan: rates and risk factors. J Shoulder Elbow Surg. 2021;30:787–794. doi: 10.1016/j.jse.2020.06.032. [DOI] [PubMed] [Google Scholar]
  • 8.Helmkamp J.K., Bullock G.S., Amilo N.R., Guerrero E.M., Ledbetter L.S., Sell T.C., et al. The clinical and radiographic impact of center of rotation lateralization in reverse shoulder arthroplasty: a systematic review. J Shoulder Elbow Surg. 2018;27:2099–2107. doi: 10.1016/j.jse.2018.07.007. [DOI] [PubMed] [Google Scholar]
  • 9.Heylen S., Van Haver A., Vuylsteke K., Declercq G., Verborgt O. Patient-specific instrument guidance of glenoid component implantation reduces inclination variability in total and reverse shoulder arthroplasty. J Shoulder Elbow Surg. 2016;25:186–192. doi: 10.1016/j.jse.2015.07.024. [DOI] [PubMed] [Google Scholar]
  • 10.Hwang S., Werner B.C., Provencher M., Horinek J.L., Moroder P., Ardebol J., et al. Short-term functional outcomes of reverse shoulder arthroplasty following three-dimensional planning is similar whether placed with a standard guide or patient-specific instrumentation. J Shoulder Elbow Surg. 2023;32:1654–1661. doi: 10.1016/j.jse.2023.02.136. [DOI] [PubMed] [Google Scholar]
  • 11.Ingrassia T., Nigrelli V., Ricotta V., Nalbone L., D'Arienzo A., D'Arienzo M., et al. A new method to evaluate the influence of the glenosphere positioning on stability and range of motion of a reverse shoulder prosthesis. Injury. 2019;50(Suppl 2):S12–S17. doi: 10.1016/j.injury.2019.01.039. [DOI] [PubMed] [Google Scholar]
  • 12.Keener J.D., Patterson B.M., Orvets N., Aleem A.W., Chamberlain A.M. Optimizing reverse shoulder arthroplasty component position in the setting of advanced arthritis with posterior glenoid erosion: a computer-enhanced range of motion analysis. J Shoulder Elbow Surg. 2018;27:339–349. doi: 10.1016/j.jse.2017.09.011. [DOI] [PubMed] [Google Scholar]
  • 13.Kim M.S., Rhee Y.G., Oh J.H., Yoo J.C., Noh K.C., Shin S.J. Clinical and radiologic outcomes of small glenoid baseplate in reverse total shoulder arthroplasty: a prospective multicenter study. Clin Orthop Surg. 2022;14:119–127. doi: 10.4055/cios20301. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 14.Klosterman E.L., Tagliero A.J., Lenters T.R., Denard P.J., Lederman E., Gobezie R., et al. The subcoracoid distance is correlated with pain and internal rotation after reverse shoulder arthroplasty. JSES Int. 2024;8:528–534. doi: 10.1016/j.jseint.2024.01.010. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 15.Kohan E.M., Chalmers P.N., Salazar D., Keener J.D., Yamaguchi K., Chamberlain A.M. Dislocation following reverse total shoulder arthroplasty. J Shoulder Elbow Surg. 2017;26:1238–1245. doi: 10.1016/j.jse.2016.12.073. [DOI] [PubMed] [Google Scholar]
  • 16.Kozak T., Bauer S., Walch G., Al-Karawi S., Blakeney W. An update on reverse total shoulder arthroplasty: current indications, new designs, same old problems. EFORT Open Rev. 2021;6:189–201. doi: 10.1302/2058-5241.6.200085. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 17.Langohr G.D., Giles J.W., Athwal G.S., Johnson J.A. The effect of glenosphere diameter in reverse shoulder arthroplasty on muscle force, joint load, and range of motion. J Shoulder Elbow Surg. 2015;24:972–979. doi: 10.1016/j.jse.2014.10.018. [DOI] [PubMed] [Google Scholar]
  • 18.Lee J.H., Kim S.H., Kim J.H., Baek G., Nakla A., McGarry M., et al. Biomechanical characteristics of glenosphere orientation based on tilting angle and overhang changes in reverse shoulder arthroplasty. Clin Orthop Surg. 2024;16:303–312. doi: 10.4055/cios23217. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 19.Li X., Knutson Z., Choi D., Lobatto D., Lipman J., Craig E.V., et al. Effects of glenosphere positioning on impingement-free internal and external rotation after reverse total shoulder arthroplasty. J Shoulder Elbow Surg. 2013;22:807–813. doi: 10.1016/j.jse.2012.07.013. [DOI] [PubMed] [Google Scholar]
  • 20.Lilley B.M., Lachance A., Peebles A.M., Powell S.N., Romeo A.A., Denard P.J., et al. What is the deviation in 3D preoperative planning software? A systematic review of concordance between plan and actual implant in reverse total shoulder arthroplasty. J Shoulder Elbow Surg. 2022;31:1073–1082. doi: 10.1016/j.jse.2021.12.006. [DOI] [PubMed] [Google Scholar]
  • 21.Liu B., Kim Y.K., Nakla A., Chung M.S., Kwak D., McGarry M.H., et al. Biomechanical consequences of glenoid and humeral lateralization in reverse total shoulder arthroplasty. J Shoulder Elbow Surg. 2023;32:1662–1672. doi: 10.1016/j.jse.2023.03.015. [DOI] [PubMed] [Google Scholar]
  • 22.Michener L.A., McClure P.W., Sennett B.J. American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form, patient self-report section: reliability, validity, and responsiveness. J Shoulder Elbow Surg. 2002;11:587–594. doi: 10.1067/mse.2002.127096. [DOI] [PubMed] [Google Scholar]
  • 23.Mollon B., Mahure S.A., Roche C.P., Zuckerman J.D. Impact of glenosphere size on clinical outcomes after reverse total shoulder arthroplasty: an analysis of 297 shoulders. J Shoulder Elbow Surg. 2016;25:763–771. doi: 10.1016/j.jse.2015.10.027. [DOI] [PubMed] [Google Scholar]
  • 24.Pak T., Ardebol J., Kilic A.I., Sears B.W., Lederman E., Werner B.C., et al. Shoulder Arthroplasty Research Committee (ShARC) Group Posteroinferior glenosphere positioning is associated with improved range of motion following reverse shoulder arthroplasty with a 135° inlay humeral component and lateralized glenoid. J Shoulder Elbow Surg. 2024;33:2171–2177. doi: 10.1016/j.jse.2024.02.019. [DOI] [PubMed] [Google Scholar]
  • 25.Pastor M.F., Kraemer M., Wellmann M., Hurschler C., Smith T. Anterior stability of the reverse shoulder arthroplasty depending on implant configuration and rotator cuff condition. Arch Orthop Trauma Surg. 2016;136:1513–1519. doi: 10.1007/s00402-016-2560-3. [DOI] [PubMed] [Google Scholar]
  • 26.Peljovich A., Ratner J.A., Marino J. Update of the physiology and biomechanics of tendon transfer surgery. J Hand Surg Am. 2010;35:1365–1369. doi: 10.1016/j.jhsa.2010.05.014. quiz 1370. [DOI] [PubMed] [Google Scholar]
  • 27.Raiss P., Walch G., Wittmann T., Athwal G.S. Is preoperative planning effective for intraoperative glenoid implant size and type selection during anatomic and reverse shoulder arthroplasty? J Shoulder Elbow Surg. 2020;29:2123–2127. doi: 10.1016/j.jse.2020.01.098. [DOI] [PubMed] [Google Scholar]
  • 28.Rodríguez J.A., Entezari V., Iannotti J.P., Ricchetti E.T. Pre-operative planning for reverse shoulder replacement: the surgical benefits and their clinical translation. Ann Jt. 2019;4:12. doi: 10.21037/aoj.2018.12.09. [DOI] [Google Scholar]
  • 29.Rojas J., Lievano, Jiménez A.M., González-Rico H.A., Salas M., Fierro G., et al. Preoperative planning in reverse shoulder arthroplasty: plain radiographs vs. computed tomography scan vs. navigation vs. augmented reality. Ann Jt. 2023;8:37. doi: 10.21037/aoj-23-20. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 30.Sabesan V.J., Lombardo D.J., Shahriar R., Petersen-Fitts G.R., Wiater J.M. The effect of glenosphere size on functional outcome for reverse shoulder arthroplasty. Musculoskelet Surg. 2016;100:115–120. doi: 10.1007/s12306-015-0396-6. [DOI] [PubMed] [Google Scholar]
  • 31.Samitier G., Alentorn-Geli E., Torrens C., Wright T.W. Reverse shoulder arthroplasty. Part 1: systematic review of clinical and functional outcomes. Int J Shoulder Surg. 2015;9:24–31. doi: 10.4103/0973-6042.150226. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 32.Saraglis G., Singh H., Charfare Z., Olujinmi G.J., Devecseri G., Agbaje A., et al. Mid-term results following reverse shoulder arthroplasty and the role of navigation in the management of glenoid bone loss. Cureus. 2024;16 doi: 10.7759/cureus.54633. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 33.Sheth M.M., Heldt B.L., Spell J.H., Vidal E.A., Laughlin M.S., Morris B.J., et al. Patient satisfaction and clinical outcomes of reverse shoulder arthroplasty: a minimum of 10 years' follow-up. J Shoulder Elbow Surg. 2022;31:875–883. doi: 10.1016/j.jse.2021.09.012. [DOI] [PubMed] [Google Scholar]
  • 34.Sheth U., Saltzman M. Reverse total shoulder arthroplasty: implant design considerations. Curr Rev Musculoskelet Med. 2019;12:554–561. doi: 10.1007/s12178-019-09585-z. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 35.Thon S.G., Seidl A.J., Bravman J.T., McCarty E.C., Savoie F.H., 3rd, Frank R.M. Advances and update on reverse total shoulder arthroplasty. Curr Rev Musculoskelet Med. 2020;13:11–19. doi: 10.1007/s12178-019-09582-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 36.Waltz R.A., Peebles A.M., Ernat J.J., Eble S.K., Denard P.J., Romeo A.A., et al. Commercial 3-dimensional imaging programs are not created equal: version and inclination measurement positions vary among preoperative planning software. JSES Int. 2022;6:413–420. doi: 10.1016/j.jseint.2022.01.006. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 37.Werner B.S., Chaoui J., Walch G. Glenosphere design affects range of movement and risk of friction-type scapular impingement in reverse shoulder arthroplasty. Bone Joint J. 2018;100-B:1182–1186. doi: 10.1302/0301-620X.100B9.BJJ-2018-0264.R1. [DOI] [PubMed] [Google Scholar]
  • 38.Werner B.C., Lederman E., Gobezie R., Denard P.J. Glenoid lateralization influences active internal rotation after reverse shoulder arthroplasty. J Shoulder Elbow Surg. 2021;30:2498–2505. doi: 10.1016/j.jse.2021.02.021. [DOI] [PubMed] [Google Scholar]

Articles from JSES International are provided here courtesy of Elsevier

RESOURCES