Long-term results of anatomic stemless shoulder prosthesis in patients with primary osteoarthritis

Long-term results of anatomic stemless shoulder prosthesis in patients with primary osteoarthritis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Long-term results of anatomic stemless shoulder prosthesis in patients with primary osteoarthritis Kevin Knappe¹, Franziska Becker¹, Raphael Trefzer¹, Mustafa Hariri¹, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6388304/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Introduction In shoulder arthroplasty shaft-anchored prostheses have long represented the gold standard. The trend has shifted towards bone-preserving, stemless anchoring methods. While promising short- and mid-term clinical results exist, there is still insufficient long-term data available. The aim of this study was to report on the long-term results in patients with primary osteoarthritis treated with a stemless shoulder prosthesis (Total Evolutive Shoulder System, Zimmer/Biomet, Warsaw, USA). Methods This retrospective single-center study was conducted on 27 shoulders in 24 patients, with a mean age of 75 ± 8.3 (60–93) years. Evaluated outcome included the Constant-Murley score, active range of motion, patient satisfaction, revision rate and radiological findings. The mean follow-up period was 142 ± 12.2 (116–158) months. Twenty-one shoulders were treated with total shoulder arthroplasty, six with hemiarthroplasty. Results Constant-Murley score improved from pre- (23.1 ± 9.4 [27.5% ± 11.5 age-adjusted]) to postoperative values (58.8 ± 18.6 [72.3% ± 23 age-adjusted]) (p < 0.001). Range of Motion improved significantly in flexion from 89.5° to 137.2° (p < 0.001), in abduction from 70.9° to 117.2° (p < 0.001), and in external rotation from 10° to 36.8° (p = 0.019). Overall, 85% of patients were very satisfied or satisfied with the shoulder replacement. Two shoulder prostheses were revised and converted to alternative treatment. Two additional patients underwent revision due to loosening and infection but were treated with the same shoulder arthroplasty system. The ten-year survival rate was 89%, and 85% after 12 years. 30% of the implants showed a risk of loosening (according to Molé). Glenoid loosening was not observed in any case. Loosening of the humeral component occurred in one case. Conclusion The clinical, functional, and radiological outcomes of the investigated stemless shoulder arthroplasty system remain satisfactory even in long-term follow-up. High patient satisfaction was observed. The data, which are unique in terms of the length of follow-up, are comparable to those of other stemless shoulder arthroplasty designs. Figures Figure 1 Figure 2 Figure 3 Introduction In shoulder arthroplasty, shaft-anchored prostheses have long represented the gold standard for treating degenerative and post-traumatic joint diseases. However, concerns regarding humeral bone loss, stress shielding, and the potential complications associated with stemmed implants such as intraoperative humeral fractures that occur at a rate of around 1.5% [1–4] have led to the development of bone-preserving, stemless shoulder prostheses [5, 6]. These could show good and similar functional outcomes, complication and revision rates compared to conventional stemmed arthroplasty [2, 7]. Some data even suggest a positive influence on the postoperative range of motion following stemless implantation compared to conventional stemmed prostheses [8]. In addition, estimated blood loss and the mean operative time are significantly lower with a stemless system [9, 10]. Instability, rotator cuff and glenoid failure are the most common causes of revision surgery [11]. In up to 50% the glenoid component shows radiographic signs of loosening [11–13]. Humeral components are therefore rather not the reason for revision, but might cause problems in revision surgery, particularly in cases involving long cemented components [14]. Stemmed and stemless shoulder arthroplasty do have the same indications, but their specific contraindications for stemless prostheses, such as poor metaphyseal bone stock, proximal humeral fractures, large metaphyseal cysts, pseudarthrosis or osteoporosis [15, 16]. Age itself is no contraindication for stemless shoulder arthroplasty surgery [17–19]. The Total Evolutive Shoulder System (T.E.S.S.- Biomet/Zimmer, Warsaw, USA) is designed to restore the shoulder joint anatomy by using a stemless humeral component that integrates to the metaphyseal bone [20]. The aim of this study was to report on long-term results of this stemless shoulder prosthesis in patients with primary osteoarthritis at a single orthopedic center. Mid-term results of this patient cohort have been published previously [21]. Methods A total of 480 shoulder arthroplasties were performed at our institution between 2009 and 2011, of which 72 were treated with the anatomical T.E.S.S.. The inclusion criteria for this study were: (a) primary osteoarthritis of the shoulder, (b) an intact rotator cuff, and (c) a minimum follow-up of 9.5 years. Forty-two cases met these criteria. Seven died before the follow-up, with their deaths not being directly related to the surgery performed. Six patients were lost to follow-up and five declined a participation in the study. Eleven patients were lost to follow-up. Thus, 24 patients with 27 shoulders could be recruited for final follow-up (Fig. 1 ). 15 shoulders were examined in the outpatient clinic, while 12 were evaluated using a certified questionnaire [22]. Both clinical and radiological assessments were conducted. The study received approval from the university's ethics board (Board-application number: S-305/2007). The clinical evaluation included the Constant-Murley score (also adjusted for age and sex), range of motion in flexion, abduction, and external rotation, as well as patient satisfaction. At the final follow-up, patients were asked to rate their satisfaction with the shoulder replacement surgery as "very satisfied," "satisfied," "undecided," or "disappointed." The surgical technique was performed following the well described approach of Kadum et. al. [23]. After a deltopectoral approach, the rotator interval is divided, the subscapularis muscle is detached, and the capsule is released along the humeral neck to facilitate adequate glenoid exposure, accompanied by osteophyte removal and anterior dislocation of the humeral head for preparation. Glenoid resurfacing, involved guidewire placement, controlled drilling, component fixation, and final stabilization, followed by subscapularis tensioning, closure, and postoperative immobilization. Radiographic evaluation : A true anteroposterior (AP) view and an axillary view of the affected shoulder were obtained preoperatively. Additionally, an MRI or CT scan was conducted to assess the integrity of the rotator cuff. At final follow-up examination, true AP and axillary view were taken (Fig. 2 ). For radiographic evaluation, 15 shoulders were included postoperatively, as part of the cohort was followed up by phone and questionnaires, as previously described. Radiographs were analyzed for signs of loosening, specifically looking for radiolucent lines around the cemented glenoid component, by two surgeons specialized in shoulder arthroplasty. The analysis followed the classification system by Molé et al. [24]. Both the AP and axillary views were assessed for radiolucent lines, and points were assigned based on their presence. The points from both views were then summed. A total of up to six points indicated no risk of loosening, 7 to 12 points suggested a risk of glenoid loosening, and a total of more than 12 points indicated a loose glenoid component. The detailed protocol has been previously described [12]. Additionally, the anatomical restoration of the proximal glenohumeral joint was assessed by measuring of the lateral offset. The glenoid morphology of the shoulders included in the study was assessed based on the Walch classification [25]. Statistical evaluation : For continuous variables, the Wilcoxon test was used for significance testing after assessing for normal distribution. Dichotomous variables, such as gender or handedness, were analyzed using the Chi-squared test. All data were analyzed using IBM SPSS Statistics (IBM Corp. Released 2023. IBM SPSS Statistics for Macintosh, Version 29.0.2.0 IBM Corp., Armonk, NY, USA) with a significance level of p < 0.05. Results Patient collective : A total of 24 patients (27 shoulders) were included in the study. The mean age at the time of surgery was 62 years (range 47–75 years). At a mean follow-up of 142 ± 12.2 months (116–158 months) postoperatively, the patients had a mean age of 75 years (± 8.3 years, range 60–93 years). The cohort consisted of 10 female and 14 male patients, with 12 left and 15 right shoulders affected. In 14 cases, the dominant side was affected, and in 13 cases, the non-dominant side. Four shoulders had undergone previous surgery prior to the arthroplasty intervention. In three cases, a conversion from a CUP prosthesis to a total shoulder arthroplasty (TSA) was performed, while in one case, a hemiarthroplasty was converted to a TSA. A total of 21 total shoulder arthroplasties and six hemiarthroplasties were implanted and followed up. A total of eight type A1 glenoids, five type A2 glenoids, three type B1 glenoids, seven type B2 glenoids, and four type C glenoids were treated surgically. All shoulders treated with a hemiarthroplasty had a type A glenoid. At the time of follow-up, 23 of the 27 implanted prostheses remained in situ. During the first year after surgery, two shoulders required revision due to loosening and infection. They were reimplanted using the T.E.S.S. system. In the other two revision cases, conversion to a conventional, shaft-anchored reverse shoulder arthroplasty (RSA) was performed after nine and thirteen years, respectively. In one of those cases, a glenoid erosion occurred following hemiarthroplasty. In the other case, the cause revision remains unknown. Table 1 Descriptive statistics Variable Value Age at preoperative assessment in years, mean (SD; range) 62 (8.1; 48–80) Gender, female/male 10 (37%) / 17 (63%) Primary osteoarthritis 23 (85%) Conversion from Hemi- to Total shoulder arthroplasty 4 (15%) Clinical follow-up in months, mean (SD; range) 142 (12.2; 116–158) Clinical results/ Constant-Murley score : Clinical outcome according to the CMS from a preoperative mean of 23.1% (9.4; 6–40) to a postoperative mean of 58.8 (18.6; 17–86) (p < 0.001) (Fig. 1 , left). Similarly, the gender-adjusted CMS (relative CMS) showed a significant improvement from 27.5% (11.5; 6.6–49.9) to 72.3% (23; 19.4–105.1) (p < 0.001) (Fig. 2 , right). Significant improvements were also observed in the subdomains. At the time of follow-up, patients reported less pain and fewer limitations in daily activities. Additionally, range of motion and strength had significantly improved (Table 2 ). Table 2 Constant-Murley score subdomains Preoperative Mean (SD, range) Postoperative/ Follow-up Mean (SD, range) p Pain (max. 15) 2.6 (2.5; 0–5) 12 (4.1; 0–15) < 0.001 Activities of daily living (max. 20) 6.3 (3.3; 2–11) 15.5 (4.1; 4–20) < 0.001 Movement (max. 40) 13.3 (7.3; 4–36) 25.5 (7.3; 4–36) < 0.001 Strength (max. 25) 0.8 (1.6; 0–5) 7.5 (4.9; 1–18) < 0.001 Radiographic evaluation : Radiographic analysis included 15 out of 25 shoulders (60%) postoperatively. The evaluation of the X-rays was conducted by two experienced shoulder surgeons. According to Molé's evaluation criteria, four shoulders were identified as being at risk for loosening. Additionally, one humeral component showed signs of loosening. No revisions were required in any case. Four shoulders exhibited periarticular ossifications. Three shoulders showed significant cranialization and two signs of stress shielding. The lateral offset preoperatively was 26.8 mm (3.3; 23.6–34.1) and postoperatively 25.3 mm (2.4; 20–37.4). Patient satisfaction : The entire patient cohort (including dropouts) was surveyed regarding their subjective satisfaction with the shoulder prosthesis surgery. The majority of patients reported being "very satisfied" or "satisfied". Four patients were "undecided" or " disappointed." Overall, 85% were "very satisfied" or "satisfied" with the outcome. Reasons for being " disappointed" included limited shoulder function and sleep disturbances on the side of the operated shoulder. Discussion This is one of the very few long-term studies evaluating patients, with a mean follow-up of 142 months that underwent stemless anatomical total shoulder arthroplasty surgery. The objective of this study was to examine the long-term clinical outcomes, radiographic parameters and implant survivorship of the anatomical T.E.S.S. prosthesis. Several studies on the stemless prosthesis described in this study (T.E.S.S.) have already reported good mid-term outcomes and an improvement in the CMS from 30 up to nearly 80 after three to four years. [21, 26]. Results of this study are comparable to the only study reporting long-term outcomes of the anatomical T.E.S.S. prosthesis [27]. 30 shoulders with a mean follow-up of 94 months showed an improvement of the CMS from 15 to 68. A survival rate was not specifically reported. But, no other long-term data on this prosthesis were available at the time of this study. When comparing the results with other stemless shoulder prostheses, similar outcomes are observed in terms of improvement in the CMS with postoperative values ranging between 70 and 80 and long-term survival rates [28, 29]. However, in the case of the study by Hawi et al., it should be noted that a large number of hemiarthroplasties were implanted, which limits comparability and reduces the significance with regard to the present study. Magosch et al. showed an estimated 13-year survivorship rate of 90.1% (Eclipse stemless shoulder prosthesis; Arthrex, Munich, Germany), Martens et al. 91.5% after 118 months (Total Evolutive Shoulder System T.E.S.S.; Biomet, USA) [30, 31]. This argument is contradicted by a survival analysis from the Australian Orthopaedic Association's National Joint Replacement Registry published in 2024, which included 3,156 implanted stemless shoulder prostheses and reported a revision rate of only 4.4% [7]. However, the mean follow-up period in this Australian registry-study was only 3.1 years (± 2.3). When looking at three years as a reference, the revision rate in the present study decreases to 7.4%. Of the 27 implanted prostheses, 23 remained in situ at the time of follow-up. Two prostheses required revision within the first postoperative year due to loosening and infection, emphasizing the importance of rigorous postoperative management. Two additional prostheses underwent conversion to reverse shoulder arthroplasty (RSA) after nine and thirteen years, respectively, due to prosthetic failure. The observed revision rate of 14.8% at the end of follow-up and the 10-year revision rate of 11.1%, respectively is slightly higher than the range reported in the mentioned studies on mid and long-term outcomes of anatomical shoulder arthroplasties. This highlights the importance of careful patient selection and precise implantation to optimize outcomes. Radiolucent lines in the region of the cemented glenoid component are a well-known long-term radiological finding of stemless shoulder prosthesis, that frequently occur in a substantial number of cases [27]. Aibinder et al. also observed in their study of 152 shoulders that stress shielding occurred in a significant number of cases, with a prevalence of 41% after a follow-up of just two years [32]. In contrast, other studies have reported a lower percentage with only 7% of cases being affected by stress shielding [33]. In that context, it is important not to confuse the different radiological appearances of stress shielding and radiolucent lines. Stress shielding reduces bone loading, causing bone resorption, while radiolucent lines indicate insufficient osseointegration or micromovement, signaling implant instability. In the present study, radiological evaluation revealed good stability and implant integration postoperatively. According to Molé's criteria, four shoulders were classified as at risk of loosening, and one humeral component exhibited signs of loosening. However, these radiological findings did not correlate with functional impairment or patient dissatisfaction. This study has several limitations that must be considered when interpreting the results. The small sample size of 27 shoulders limits the statistical power and generalizability of the findings. Larger cohorts are necessary to validate these outcomes in a broader population. The radiological evaluation was conducted in 15 of 25 shoulders (60%) due to the follow-up methodology. This limitation may have affected the ability to comprehensively assess radiological changes. Furthermore, the retrospective design of the study introduces a potential for selection bias and incomplete data collection, which could influence the robustness of the conclusions. Finally, the lack of a control group comparing stemless anatomical shoulder prostheses to stemmed prostheses or other stemless models limits the ability to draw direct comparisons and assess the relative advantages or disadvantages of the two approaches. To the best of our knowledge, long-term results from comparative studies on stemless and stemmed shoulder prostheses are not available. However, both short-term comparisons and a meta-analysis by Liu et al. (2020) found no significant differences in postoperative CMS or complication rates [9, 10, 34]. These limitations highlight the need for future prospective studies with larger patient populations and controlled comparative designs. Our study demonstrates that stemless anatomical shoulder arthroplasty is an effective option for the treatment of end-stage degenerative shoulder conditions. The results indicate significant improvements in clinical function and pain reduction, with most implants remaining stable over time. Conclusion The clinical and radiological outcomes of the investigated stemless shoulder arthroplasty system remain satisfactory even in the long-term follow-up. High patient satisfaction along with significant improvements in clinical function and pain reduction was observed. The results are comparable to those of other stemless shoulder arthroplasty designs, but due to the exceptionally long follow-up period, they are nearly unique. However, the observed revisions and radiological changes warrant further investigation to optimize biomechanical properties and clinical outcomes of these implants. Declarations Ethics approval and consent to participate: The study received approval from the university's ethics board (Board-application number: S-305/2007). The study was conducted in accordance with the Helsinki Declaration of 1975, as revised in 2013. Informed consent was obtained from all participating patients. Consent for publication: All authors have read and agreed to the published version of the manuscript. Availability of data and materials: The dataset used and/or analyzed during the current study is available from the corresponding author upon reasonable request. Competing interests: M.B. is a paid consultant for Stryker (Memphis, TN, USA). A.K.N. has received lecture fees by DePuy Synthes (Warsaw, IN, USA). The other authors declare no conflict of interest. Funding: No funding or support was received. Authors' contributions: Conceptualization: M.B., K.K. and F.B.; Formal analysis: F.B. and K.K.; Data curation: F.B, K.K. and M.B.; Project administration: F.B., K.K. and A.K.N., Writing—original draft preparation: K.K. and F.B.; Writing—review and editing: K.K., F.B., R.T., M.H., A.K.N. and M.B.. Clinical trial/ registry number: Not applicable. Acknowledgements: Not applicable. References Dolci, A., et al., Complications and Intraoperative Fractures in Reverse Shoulder Arthroplasty: A Systematic Review. Geriatr Orthop Surg Rehabil, 2021. 12 : p. 21514593211059865. 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J Shoulder Elbow Surg, 2017. 26 (9): p. 1609-1615. Magosch, P., S. Lichtenberg, and P. Habermeyer, Survival of stemless humeral head replacement in anatomic shoulder arthroplasty: a prospective study. J Shoulder Elbow Surg, 2021. 30 (7): p. e343-e355. Martens, N., et al., Long-term survival and failure analysis of anatomical stemmed and stemless shoulder arthroplasties. Bone Joint J, 2021. 103-B (7): p. 1292-1300. Aibinder, W.R., et al., Stress shielding following stemless anatomic total shoulder arthroplasty. Shoulder Elbow, 2023. 15 (1): p. 54-60. Magone, K.M., et al., Short-term radiographic analysis of a stemless humeral component for anatomic total shoulder arthroplasty. JSES Int, 2023. 7 (2): p. 285-289. Maier, M.W., et al., Are there differences between stemless and conventional stemmed shoulder prostheses in the treatment of glenohumeral osteoarthritis? BMC Musculoskelet Disord, 2015. 16 : p. 275. Additional Declarations Competing interest reported. M.B. is a paid consultant for Stryker (Memphis, TN, USA). A.K.N. has received lecture fees by DePuy Synthes (Warsaw, IN, USA). The other authors declare no conflict of interest. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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18:53:07","currentVersionCode":1,"declarations":{"humanSubjects":false,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-6388304/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6388304/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":82354053,"identity":"f933456e-f6ab-4408-b791-2168c0fa5570","added_by":"auto","created_at":"2025-05-09 11:09:17","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":72811,"visible":true,"origin":"","legend":"\u003cp\u003eFlowchart of patient recruitment\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6388304/v1/c68b74be08416687662c5d49.png"},{"id":82356181,"identity":"fcd07e59-661e-42ed-9352-a154af8475ed","added_by":"auto","created_at":"2025-05-09 11:17:17","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":46331,"visible":true,"origin":"","legend":"\u003cp\u003eConstant-Murley score (left) and CMS adjusted for age and sex (right), both pre- and postoperative\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6388304/v1/297cbc87e50ca7da88197a9c.jpg"},{"id":82356184,"identity":"da004251-c358-47ba-a51c-714af36c3c77","added_by":"auto","created_at":"2025-05-09 11:17:17","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":304913,"visible":true,"origin":"","legend":"\u003cp\u003ePre- and postoperative radiograph of a left shoulder.\u003c/p\u003e","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6388304/v1/66e06f71fcf0bde7f84ef186.jpeg"},{"id":84809012,"identity":"faf48623-f2d9-494a-9e2f-6cb4bf145b05","added_by":"auto","created_at":"2025-06-17 14:38:55","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":856048,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6388304/v1/de905592-c4cd-49a3-b051-858bd8e49532.pdf"}],"financialInterests":"Competing interest reported. M.B. is a paid consultant for Stryker (Memphis, TN, USA). A.K.N. has received lecture fees by DePuy Synthes (Warsaw, IN, USA). The other authors declare no conflict of interest.","formattedTitle":"Long-term results of anatomic stemless shoulder prosthesis in patients with primary osteoarthritis","fulltext":[{"header":"Introduction","content":"\u003cp\u003eIn shoulder arthroplasty, shaft-anchored prostheses have long represented the gold standard for treating degenerative and post-traumatic joint diseases. However, concerns regarding humeral bone loss, stress shielding, and the potential complications associated with stemmed implants such as intraoperative humeral fractures that occur at a rate of around 1.5% [1–4] have led to the development of bone-preserving, stemless shoulder prostheses [5, 6]. These could show good and similar functional outcomes, complication and revision rates compared to conventional stemmed arthroplasty [2, 7]. Some data even suggest a positive influence on the postoperative range of motion following stemless implantation compared to conventional stemmed prostheses [8]. In addition, estimated blood loss and the mean operative time are significantly lower with a stemless system [9, 10].\u003c/p\u003e \u003cp\u003eInstability, rotator cuff and glenoid failure are the most common causes of revision surgery [11]. In up to 50% the glenoid component shows radiographic signs of loosening [11–13]. Humeral components are therefore rather not the reason for revision, but might cause problems in revision surgery, particularly in cases involving long cemented components [14].\u003c/p\u003e \u003cp\u003eStemmed and stemless shoulder arthroplasty do have the same indications, but their specific contraindications for stemless prostheses, such as poor metaphyseal bone stock, proximal humeral fractures, large metaphyseal cysts, pseudarthrosis or osteoporosis [15, 16]. Age itself is no contraindication for stemless shoulder arthroplasty surgery [17–19].\u003c/p\u003e \u003cp\u003eThe Total Evolutive Shoulder System (T.E.S.S.- Biomet/Zimmer, Warsaw, USA) is designed to restore the shoulder joint anatomy by using a stemless humeral component that integrates to the metaphyseal bone [20]. The aim of this study was to report on long-term results of this stemless shoulder prosthesis in patients with primary osteoarthritis at a single orthopedic center. Mid-term results of this patient cohort have been published previously [21].\u003c/p\u003e "},{"header":"Methods","content":"\u003cp\u003eA total of 480 shoulder arthroplasties were performed at our institution between 2009 and 2011, of which 72 were treated with the anatomical T.E.S.S.. The inclusion criteria for this study were: (a) primary osteoarthritis of the shoulder, (b) an intact rotator cuff, and (c) a minimum follow-up of 9.5 years. Forty-two cases met these criteria. Seven died before the follow-up, with their deaths not being directly related to the surgery performed. Six patients were lost to follow-up and five declined a participation in the study. Eleven patients were lost to follow-up. Thus, 24 patients with 27 shoulders could be recruited for final follow-up (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). 15 shoulders were examined in the outpatient clinic, while 12 were evaluated using a certified questionnaire [22].\u003c/p\u003e\u003cp\u003eBoth clinical and radiological assessments were conducted. The study received approval from the university's ethics board (Board-application number: S-305/2007). The clinical evaluation included the Constant-Murley score (also adjusted for age and sex), range of motion in flexion, abduction, and external rotation, as well as patient satisfaction. At the final follow-up, patients were asked to rate their satisfaction with the shoulder replacement surgery as \"very satisfied,\" \"satisfied,\" \"undecided,\" or \"disappointed.\"\u003c/p\u003e\u003cp\u003eThe surgical technique was performed following the well described approach of Kadum et. al. [23]. After a deltopectoral approach, the rotator interval is divided, the subscapularis muscle is detached, and the capsule is released along the humeral neck to facilitate adequate glenoid exposure, accompanied by osteophyte removal and anterior dislocation of the humeral head for preparation. Glenoid resurfacing, involved guidewire placement, controlled drilling, component fixation, and final stabilization, followed by subscapularis tensioning, closure, and postoperative immobilization.\u003c/p\u003e\u003cp\u003e \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eRadiographic evaluation\u003c/span\u003e: A true anteroposterior (AP) view and an axillary view of the affected shoulder were obtained preoperatively. Additionally, an MRI or CT scan was conducted to assess the integrity of the rotator cuff. At final follow-up examination, true AP and axillary view were taken (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). For radiographic evaluation, 15 shoulders were included postoperatively, as part of the cohort was followed up by phone and questionnaires, as previously described.\u003c/p\u003e\u003cp\u003eRadiographs were analyzed for signs of loosening, specifically looking for radiolucent lines around the cemented glenoid component, by two surgeons specialized in shoulder arthroplasty. The analysis followed the classification system by Molé et al. [24]. Both the AP and axillary views were assessed for radiolucent lines, and points were assigned based on their presence. The points from both views were then summed. A total of up to six points indicated no risk of loosening, 7 to 12 points suggested a risk of glenoid loosening, and a total of more than 12 points indicated a loose glenoid component. The detailed protocol has been previously described [12]. Additionally, the anatomical restoration of the proximal glenohumeral joint was assessed by measuring of the lateral offset. The glenoid morphology of the shoulders included in the study was assessed based on the Walch classification [25].\u003c/p\u003e\u003cp\u003e \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eStatistical evaluation\u003c/span\u003e: For continuous variables, the Wilcoxon test was used for significance testing after assessing for normal distribution. Dichotomous variables, such as gender or handedness, were analyzed using the Chi-squared test. All data were analyzed using IBM SPSS Statistics (IBM Corp. Released 2023. IBM SPSS Statistics for Macintosh, Version 29.0.2.0 IBM Corp., Armonk, NY, USA) with a significance level of p \u0026lt; 0.05.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003ePatient collective\u003c/span\u003e: A total of 24 patients (27 shoulders) were included in the study. The mean age at the time of surgery was 62 years (range 47\u0026ndash;75 years). At a mean follow-up of 142\u0026thinsp;\u0026plusmn;\u0026thinsp;12.2 months (116\u0026ndash;158 months) postoperatively, the patients had a mean age of 75 years (\u0026plusmn;\u0026thinsp;8.3 years, range 60\u0026ndash;93 years). The cohort consisted of 10 female and 14 male patients, with 12 left and 15 right shoulders affected. In 14 cases, the dominant side was affected, and in 13 cases, the non-dominant side. Four shoulders had undergone previous surgery prior to the arthroplasty intervention. In three cases, a conversion from a CUP prosthesis to a total shoulder arthroplasty (TSA) was performed, while in one case, a hemiarthroplasty was converted to a TSA.\u003c/p\u003e \u003cp\u003eA total of 21 total shoulder arthroplasties and six hemiarthroplasties were implanted and followed up. A total of eight type A1 glenoids, five type A2 glenoids, three type B1 glenoids, seven type B2 glenoids, and four type C glenoids were treated surgically. All shoulders treated with a hemiarthroplasty had a type A glenoid.\u003c/p\u003e \u003cp\u003eAt the time of follow-up, 23 of the 27 implanted prostheses remained in situ. During the first year after surgery, two shoulders required revision due to loosening and infection. They were reimplanted using the T.E.S.S. system. In the other two revision cases, conversion to a conventional, shaft-anchored reverse shoulder arthroplasty (RSA) was performed after nine and thirteen years, respectively. In one of those cases, a glenoid erosion occurred following hemiarthroplasty. In the other case, the cause revision remains unknown.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDescriptive statistics\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eValue\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge at preoperative assessment in years, mean (SD; range)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e62 (8.1; 48\u0026ndash;80)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGender, female/male\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10 (37%) / 17 (63%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrimary osteoarthritis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23 (85%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eConversion from Hemi- to Total shoulder arthroplasty\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4 (15%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eClinical follow-up in months, mean (SD; range)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e142 (12.2; 116\u0026ndash;158)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eClinical results/ Constant-Murley score\u003c/span\u003e: Clinical outcome according to the CMS from a preoperative mean of 23.1% (9.4; 6\u0026ndash;40) to a postoperative mean of 58.8 (18.6; 17\u0026ndash;86) (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, left). Similarly, the gender-adjusted CMS (relative CMS) showed a significant improvement from 27.5% (11.5; 6.6\u0026ndash;49.9) to 72.3% (23; 19.4\u0026ndash;105.1) (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, right).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eSignificant improvements were also observed in the subdomains. At the time of follow-up, patients reported less pain and fewer limitations in daily activities. Additionally, range of motion and strength had significantly improved (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eConstant-Murley score subdomains\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePreoperative\u003c/p\u003e \u003cp\u003eMean (SD, range)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePostoperative/ Follow-up\u003c/p\u003e \u003cp\u003eMean (SD, range)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ep\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePain (max. 15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2.6 (2.5; 0\u0026ndash;5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e12 (4.1; 0\u0026ndash;15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eActivities of daily living (max. 20)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6.3 (3.3; 2\u0026ndash;11)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e15.5 (4.1; 4\u0026ndash;20)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMovement (max. 40)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e13.3 (7.3; 4\u0026ndash;36)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e25.5 (7.3; 4\u0026ndash;36)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStrength (max. 25)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.8 (1.6; 0\u0026ndash;5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e7.5 (4.9; 1\u0026ndash;18)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eRadiographic evaluation\u003c/span\u003e: Radiographic analysis included 15 out of 25 shoulders (60%) postoperatively. The evaluation of the X-rays was conducted by two experienced shoulder surgeons. According to Mol\u0026eacute;'s evaluation criteria, four shoulders were identified as being at risk for loosening. Additionally, one humeral component showed signs of loosening. No revisions were required in any case. Four shoulders exhibited periarticular ossifications. Three shoulders showed significant cranialization and two signs of stress shielding. The lateral offset preoperatively was 26.8 mm (3.3; 23.6\u0026ndash;34.1) and postoperatively 25.3 mm (2.4; 20\u0026ndash;37.4).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003ePatient satisfaction\u003c/span\u003e: The entire patient cohort (including dropouts) was surveyed regarding their subjective satisfaction with the shoulder prosthesis surgery. The majority of patients reported being \"very satisfied\" or \"satisfied\". Four patients were \"undecided\" or \" disappointed.\" Overall, 85% were \"very satisfied\" or \"satisfied\" with the outcome. Reasons for being \" disappointed\" included limited shoulder function and sleep disturbances on the side of the operated shoulder.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis is one of the very few long-term studies evaluating patients, with a mean follow-up of 142 months that underwent stemless anatomical total shoulder arthroplasty surgery. The objective of this study was to examine the long-term clinical outcomes, radiographic parameters and implant survivorship of the anatomical T.E.S.S. prosthesis.\u003c/p\u003e \u003cp\u003eSeveral studies on the stemless prosthesis described in this study (T.E.S.S.) have already reported good mid-term outcomes and an improvement in the CMS from 30 up to nearly 80 after three to four years. [21, 26]. Results of this study are comparable to the only study reporting long-term outcomes of the anatomical T.E.S.S. prosthesis [27]. 30 shoulders with a mean follow-up of 94 months showed an improvement of the CMS from 15 to 68. A survival rate was not specifically reported. But, no other long-term data on this prosthesis were available at the time of this study. When comparing the results with other stemless shoulder prostheses, similar outcomes are observed in terms of improvement in the CMS with postoperative values ranging between 70 and 80 and long-term survival rates [28, 29]. However, in the case of the study by Hawi et al., it should be noted that a large number of hemiarthroplasties were implanted, which limits comparability and reduces the significance with regard to the present study.\u003c/p\u003e \u003cp\u003eMagosch et al. showed an estimated 13-year survivorship rate of 90.1% (Eclipse stemless shoulder prosthesis; Arthrex, Munich, Germany), Martens et al. 91.5% after 118 months (Total Evolutive Shoulder System T.E.S.S.; Biomet, USA) [30, 31]. This argument is contradicted by a survival analysis from the Australian Orthopaedic Association's National Joint Replacement Registry published in 2024, which included 3,156 implanted stemless shoulder prostheses and reported a revision rate of only 4.4% [7]. However, the mean follow-up period in this Australian registry-study was only 3.1 years (\u0026plusmn;\u0026thinsp;2.3). When looking at three years as a reference, the revision rate in the present study decreases to 7.4%. Of the 27 implanted prostheses, 23 remained in situ at the time of follow-up. Two prostheses required revision within the first postoperative year due to loosening and infection, emphasizing the importance of rigorous postoperative management. Two additional prostheses underwent conversion to reverse shoulder arthroplasty (RSA) after nine and thirteen years, respectively, due to prosthetic failure. The observed revision rate of 14.8% at the end of follow-up and the 10-year revision rate of 11.1%, respectively is slightly higher than the range reported in the mentioned studies on mid and long-term outcomes of anatomical shoulder arthroplasties. This highlights the importance of careful patient selection and precise implantation to optimize outcomes.\u003c/p\u003e \u003cp\u003eRadiolucent lines in the region of the cemented glenoid component are a well-known long-term radiological finding of stemless shoulder prosthesis, that frequently occur in a substantial number of cases [27]. Aibinder et al. also observed in their study of 152 shoulders that stress shielding occurred in a significant number of cases, with a prevalence of 41% after a follow-up of just two years [32]. In contrast, other studies have reported a lower percentage with only 7% of cases being affected by stress shielding [33]. In that context, it is important not to confuse the different radiological appearances of stress shielding and radiolucent lines. Stress shielding reduces bone loading, causing bone resorption, while radiolucent lines indicate insufficient osseointegration or micromovement, signaling implant instability. In the present study, radiological evaluation revealed good stability and implant integration postoperatively. According to Mol\u0026eacute;'s criteria, four shoulders were classified as at risk of loosening, and one humeral component exhibited signs of loosening. However, these radiological findings did not correlate with functional impairment or patient dissatisfaction.\u003c/p\u003e \u003cp\u003eThis study has several limitations that must be considered when interpreting the results. The small sample size of 27 shoulders limits the statistical power and generalizability of the findings. Larger cohorts are necessary to validate these outcomes in a broader population. The radiological evaluation was conducted in 15 of 25 shoulders (60%) due to the follow-up methodology. This limitation may have affected the ability to comprehensively assess radiological changes. Furthermore, the retrospective design of the study introduces a potential for selection bias and incomplete data collection, which could influence the robustness of the conclusions. Finally, the lack of a control group comparing stemless anatomical shoulder prostheses to stemmed prostheses or other stemless models limits the ability to draw direct comparisons and assess the relative advantages or disadvantages of the two approaches. To the best of our knowledge, long-term results from comparative studies on stemless and stemmed shoulder prostheses are not available. However, both short-term comparisons and a meta-analysis by Liu et al. (2020) found no significant differences in postoperative CMS or complication rates [9, 10, 34]. These limitations highlight the need for future prospective studies with larger patient populations and controlled comparative designs.\u003c/p\u003e \u003cp\u003eOur study demonstrates that stemless anatomical shoulder arthroplasty is an effective option for the treatment of end-stage degenerative shoulder conditions. The results indicate significant improvements in clinical function and pain reduction, with most implants remaining stable over time.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThe clinical and radiological outcomes of the investigated stemless shoulder arthroplasty system remain satisfactory even in the long-term follow-up. High patient satisfaction along with significant improvements in clinical function and pain reduction was observed. The results are comparable to those of other stemless shoulder arthroplasty designs, but due to the exceptionally long follow-up period, they are nearly unique. However, the observed revisions and radiological changes warrant further investigation to optimize biomechanical properties and clinical outcomes of these implants.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cu\u003eEthics approval and consent to participate:\u003c/u\u003e The study received approval from the university\u0026apos;s ethics board (Board-application number: S-305/2007). The study was conducted in accordance with the Helsinki Declaration of 1975, as revised in 2013. Informed consent was obtained from all participating patients.\u003c/p\u003e\n\u003cp\u003e\u003cu\u003eConsent for publication:\u003c/u\u003e All authors have read and agreed to the published version of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cu\u003eAvailability of data and materials:\u003c/u\u003e The dataset used and/or analyzed during the current study is available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cu\u003eCompeting interests:\u003c/u\u003e M.B. is a paid consultant for Stryker (Memphis, TN, USA). A.K.N. has received lecture fees by DePuy Synthes (Warsaw, IN, USA). The other authors declare no conflict of interest.\u003c/p\u003e\n\u003cp\u003e\u003cu\u003eFunding:\u003c/u\u003e No funding or support was received.\u003c/p\u003e\n\u003cp\u003e\u003cu\u003eAuthors\u0026apos; contributions:\u003c/u\u003e Conceptualization: M.B., K.K. and F.B.; Formal analysis: F.B. and K.K.; Data curation: F.B, K.K. and M.B.; Project administration: F.B., K.K. and A.K.N., Writing\u0026mdash;original draft preparation: K.K. and F.B.; Writing\u0026mdash;review and editing: K.K., F.B., R.T., M.H., A.K.N. and M.B..\u003c/p\u003e\n\u003cp\u003e\u003cu\u003eClinical trial/ registry number:\u003c/u\u003e Not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cu\u003eAcknowledgements:\u003c/u\u003e Not applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eDolci, A., et al., \u003cem\u003eComplications and Intraoperative Fractures in Reverse Shoulder Arthroplasty: A Systematic Review.\u003c/em\u003e Geriatr Orthop Surg Rehabil, 2021. \u003cstrong\u003e12\u003c/strong\u003e: p. 21514593211059865.\u003c/li\u003e\n\u003cli\u003eWixted, C.M., et al., \u003cem\u003eIntraoperative fractures in shoulder arthroplasty: risk factors and outcomes.\u003c/em\u003e JSES Int, 2021. \u003cstrong\u003e5\u003c/strong\u003e(6): p. 1021-1026.\u003c/li\u003e\n\u003cli\u003eAthwal, G.S., et al., \u003cem\u003ePeriprosthetic humeral fractures during shoulder arthroplasty.\u003c/em\u003e J Bone Joint Surg Am, 2009. \u003cstrong\u003e91\u003c/strong\u003e(3): p. 594-603.\u003c/li\u003e\n\u003cli\u003eGarcia-Fernandez, C., et al., \u003cem\u003ePeriprosthetic humeral fractures associated with reverse total shoulder arthroplasty: incidence and management.\u003c/em\u003e Int Orthop, 2015. \u003cstrong\u003e39\u003c/strong\u003e(10): p. 1965-9.\u003c/li\u003e\n\u003cli\u003eChurchill, R.S., \u003cem\u003eStemless shoulder arthroplasty: current status.\u003c/em\u003e J Shoulder Elbow Surg, 2014. \u003cstrong\u003e23\u003c/strong\u003e(9): p. 1409-14.\u003c/li\u003e\n\u003cli\u003eHatta, T., et al., \u003cem\u003eEvolution of Stemless Reverse Shoulder Arthroplasty: Current Indications, Outcomes, and Future Prospects.\u003c/em\u003e J Clin Med, 2024. \u003cstrong\u003e13\u003c/strong\u003e(13).\u003c/li\u003e\n\u003cli\u003eAldinger, P.R., et al., \u003cem\u003eComplications in shoulder arthroplasty: an analysis of 485 cases.\u003c/em\u003e Int Orthop, 2010. \u003cstrong\u003e34\u003c/strong\u003e(4): p. 517-24.\u003c/li\u003e\n\u003cli\u003eShin, Y.S., W.S. 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A Systematic Review of the Literature.\u003c/em\u003e Orthop J Sports Med, 2020. \u003cstrong\u003e8\u003c/strong\u003e(9): p. 2325967120950307.\u003c/li\u003e\n\u003cli\u003eHolschen, M., et al., \u003cem\u003eIs reverse total shoulder arthroplasty a feasible treatment option for failed shoulder arthroplasty? A retrospective study of 44 cases with special regards to stemless and stemmed primary implants.\u003c/em\u003e Musculoskelet Surg, 2017. \u003cstrong\u003e101\u003c/strong\u003e(2): p. 173-180.\u003c/li\u003e\n\u003cli\u003eNourissat, G., et al., \u003cem\u003eStemless Shoulder Arthroplasty.\u003c/em\u003e Instr Course Lect, 2022. \u003cstrong\u003e71\u003c/strong\u003e: p. 377-384.\u003c/li\u003e\n\u003cli\u003eSmith, T., et al., \u003cem\u003eShort-term results of a new anatomic stemless shoulder arthroplasty - A prospective multicentre study.\u003c/em\u003e Orthop Rev (Pavia), 2022. \u003cstrong\u003e14\u003c/strong\u003e(4): p. 37042.\u003c/li\u003e\n\u003cli\u003eBaumgarten, K.M., \u003cem\u003eIs stemless total shoulder arthroplasty indicated in elderly patients?\u003c/em\u003e J Shoulder Elbow Surg, 2023. \u003cstrong\u003e32\u003c/strong\u003e(2): p. 260-268.\u003c/li\u003e\n\u003cli\u003eMonteiro, H.L., et al., \u003cem\u003eInfluence of age-related bone density changes on primary stability in stemless shoulder arthroplasty: a multi-implant finite element study.\u003c/em\u003e J Shoulder Elbow Surg, 2024.\u003c/li\u003e\n\u003cli\u003eGoldberg, S.S., et al., \u003cem\u003eAnatomic total shoulder arthroplasty using a stem-free ellipsoid humeral implant in patients of all ages.\u003c/em\u003e J Shoulder Elbow Surg, 2021. \u003cstrong\u003e30\u003c/strong\u003e(9): p. e572-e582.\u003c/li\u003e\n\u003cli\u003eGeurts, G.F., et al., \u003cem\u003ePlacement of the stemless humeral component in the Total Evolutive Shoulder System (TESS).\u003c/em\u003e Tech Hand Up Extrem Surg, 2010. \u003cstrong\u003e14\u003c/strong\u003e(4): p. 214-7.\u003c/li\u003e\n\u003cli\u003eBulhoff, M., et al., \u003cem\u003eMid-term results with an anatomic stemless shoulder prosthesis in patients with primary osteoarthritis.\u003c/em\u003e Acta Orthop Traumatol Turc, 2019. \u003cstrong\u003e53\u003c/strong\u003e(3): p. 170-174.\u003c/li\u003e\n\u003cli\u003eBoehm, D., et al., \u003cem\u003e[Development of a questionnaire based on the Constant-Murley-Score for self-evaluation of shoulder function by patients].\u003c/em\u003e Unfallchirurg, 2004. \u003cstrong\u003e107\u003c/strong\u003e(5): p. 397-402.\u003c/li\u003e\n\u003cli\u003eKadum, B., et al., \u003cem\u003eResults of the Total Evolutive Shoulder System (TESS): a single-centre study of 56 consecutive patients.\u003c/em\u003e Arch Orthop Trauma Surg, 2011. \u003cstrong\u003e131\u003c/strong\u003e(12): p. 1623-9.\u003c/li\u003e\n\u003cli\u003eMol\u0026eacute;, D., Roche, O., Riand, N., L\u0026eacute;vigne, C., Walch, G., \u003cem\u003eCemented Glenoid Component: Results in Osteoarthritis and Rheumatoid Arthritis.\u003c/em\u003e Walch, G., Boileau, P. (eds) Shoulder Arthroplasty. , 1999: p. 163- 171.\u003c/li\u003e\n\u003cli\u003eWalch, G., et al., \u003cem\u003eMorphologic study of the glenoid in primary glenohumeral osteoarthritis.\u003c/em\u003e J Arthroplasty, 1999. \u003cstrong\u003e14\u003c/strong\u003e(6): p. 756-60.\u003c/li\u003e\n\u003cli\u003eHuguet, D., et al., \u003cem\u003eResults of a new stemless shoulder prosthesis: radiologic proof of maintained fixation and stability after a minimum of three years\u0026apos; follow-up.\u003c/em\u003e J Shoulder Elbow Surg, 2010. \u003cstrong\u003e19\u003c/strong\u003e(6): p. 847-52.\u003c/li\u003e\n\u003cli\u003eBeck, S., et al., \u003cem\u003eLong-Term Radiographic Changes in Stemless Press-Fit Total Shoulder Arthroplasty.\u003c/em\u003e Z Orthop Unfall, 2021. \u003cstrong\u003e159\u003c/strong\u003e(3): p. 274-280.\u003c/li\u003e\n\u003cli\u003eHabermeyer, P., et al., \u003cem\u003eMidterm results of stemless shoulder arthroplasty: a prospective study.\u003c/em\u003e J Shoulder Elbow Surg, 2015. \u003cstrong\u003e24\u003c/strong\u003e(9): p. 1463-72.\u003c/li\u003e\n\u003cli\u003eHawi, N., et al., \u003cem\u003eNine-year outcome after anatomic stemless shoulder prosthesis: clinical and radiologic results.\u003c/em\u003e J Shoulder Elbow Surg, 2017. \u003cstrong\u003e26\u003c/strong\u003e(9): p. 1609-1615.\u003c/li\u003e\n\u003cli\u003eMagosch, P., S. Lichtenberg, and P. Habermeyer, \u003cem\u003eSurvival of stemless humeral head replacement in anatomic shoulder arthroplasty: a prospective study.\u003c/em\u003e J Shoulder Elbow Surg, 2021. \u003cstrong\u003e30\u003c/strong\u003e(7): p. e343-e355.\u003c/li\u003e\n\u003cli\u003eMartens, N., et al., \u003cem\u003eLong-term survival and failure analysis of anatomical stemmed and stemless shoulder arthroplasties.\u003c/em\u003e Bone Joint J, 2021. \u003cstrong\u003e103-B\u003c/strong\u003e(7): p. 1292-1300.\u003c/li\u003e\n\u003cli\u003eAibinder, W.R., et al., \u003cem\u003eStress shielding following stemless anatomic total shoulder arthroplasty.\u003c/em\u003e Shoulder Elbow, 2023. \u003cstrong\u003e15\u003c/strong\u003e(1): p. 54-60.\u003c/li\u003e\n\u003cli\u003eMagone, K.M., et al., \u003cem\u003eShort-term radiographic analysis of a stemless humeral component for anatomic total shoulder arthroplasty.\u003c/em\u003e JSES Int, 2023. \u003cstrong\u003e7\u003c/strong\u003e(2): p. 285-289.\u003c/li\u003e\n\u003cli\u003eMaier, M.W., et al., \u003cem\u003eAre there differences between stemless and conventional stemmed shoulder prostheses in the treatment of glenohumeral osteoarthritis?\u003c/em\u003e BMC Musculoskelet Disord, 2015. \u003cstrong\u003e16\u003c/strong\u003e: p. 275.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-6388304/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6388304/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eIntroduction\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn shoulder arthroplasty shaft-anchored prostheses have long represented the gold standard. The trend has shifted towards bone-preserving, stemless anchoring methods. While promising short- and mid-term clinical results exist, there is still insufficient long-term data available. The aim of this study was to report on the long-term results in patients with primary osteoarthritis treated with a stemless shoulder prosthesis (Total Evolutive Shoulder System, Zimmer/Biomet, Warsaw, USA).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis retrospective single-center study was conducted on 27 shoulders in 24 patients, with a mean age of 75 ± 8.3 (60–93) years. Evaluated outcome included the Constant-Murley score, active range of motion, patient satisfaction, revision rate and radiological findings. The mean follow-up period was 142 ± 12.2 (116–158) months. Twenty-one shoulders were treated with total shoulder arthroplasty, six with hemiarthroplasty.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eConstant-Murley score improved from pre- (23.1 ± 9.4 [27.5% ± 11.5 age-adjusted]) to postoperative values (58.8 ± 18.6 [72.3% ± 23 age-adjusted]) (p \u0026lt; 0.001). Range of Motion improved significantly in flexion from 89.5° to 137.2° (p \u0026lt; 0.001), in abduction from 70.9° to 117.2° (p \u0026lt; 0.001), and in external rotation from 10° to 36.8° (p = 0.019). Overall, 85% of patients were very satisfied or satisfied with the shoulder replacement. Two shoulder prostheses were revised and converted to alternative treatment. Two additional patients underwent revision due to loosening and infection but were treated with the same shoulder arthroplasty system. The ten-year survival rate was 89%, and 85% after 12 years. 30% of the implants showed a risk of loosening (according to Molé). Glenoid loosening was not observed in any case. Loosening of the humeral component occurred in one case.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe clinical, functional, and radiological outcomes of the investigated stemless shoulder arthroplasty system remain satisfactory even in long-term follow-up. High patient satisfaction was observed. The data, which are unique in terms of the length of follow-up, are comparable to those of other stemless shoulder arthroplasty designs.\u003c/p\u003e","manuscriptTitle":"Long-term results of anatomic stemless shoulder prosthesis in patients with primary osteoarthritis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-09 11:09:13","doi":"10.21203/rs.3.rs-6388304/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"0bb51d3f-ec4c-4b8b-a756-5af658524246","owner":[],"postedDate":"May 9th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-06-17T14:38:45+00:00","versionOfRecord":[],"versionCreatedAt":"2025-05-09 11:09:13","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6388304","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6388304","identity":"rs-6388304","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}