Effects of proximal smooth pegs on surgical outcomes of plate fixation for proximal humeral fractures

Effects of proximal smooth pegs on surgical outcomes of plate fixation for proximal humeral fractures | 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 Effects of proximal smooth pegs on surgical outcomes of plate fixation for proximal humeral fractures Ryogo Furuhata, Atsushi Tanji, Satoshi Oki, Noboru Matsumura This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9071472/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 7 You are reading this latest preprint version Abstract Background Plate fixation yields satisfactory functional outcomes in proximal humeral fractures; nonetheless, a relatively high complication rate has been reported. Smooth pegs were introduced to reduce proximal screw cut-out. However, no direct comparison has been performed between proximal pegs and screws within the same plate system. This study aimed to compare the surgical outcomes of osteosynthesis with ALPS plates featuring proximal pegs and screws. Methods Fifty-four patients who had undergone plate fixation for proximal humeral fractures were retrospectively identified. All operations were performed by the same surgeon using a deltopectoral approach. Whereas ALPS plates fixed exclusively with proximal pegs were used prior to January 2024 (peg group, 26 patients), those with exclusive proximal screw fixation were used after February 2024 (screw group, 28 patients). As an outcome measure, we assessed postoperative shoulder functional scores and compared the two groups regarding the respective rates of complication. Results At 1 year postoperatively, no significant between-group differences were observed in the adjusted Constant and American Shoulder and Elbow Surgeons scores. Nonetheless, the incidence of loss of greater tuberosity reduction was significantly higher in the peg group than in the screw group (23.1% vs. 3.6%, P = 0.047). Conversely, three patients required revision surgery because of symptomatic proximal implant penetration or varus progression in the screw group, whereas no patients required reoperation in the peg group. Conclusions The use of proximal pegs rather than screws did not significantly affect postoperative functional outcomes, although reoperation was not required in the peg group. Nevertheless, proximal threaded screws are recommended for three-part fractures to reduce the risk of secondary displacement of the greater tuberosity. Trial registration: Not applicable. proximal humeral fracture plate fixation outcome peg screw Figures Figure 1 Introduction Locking plate-mediated osteosynthesis is a widely used surgical technique for the treatment of proximal humeral fractures. Nonetheless, a relatively high postoperative complication rate has been reported [ 1 , 2 ], among which, intra-articular penetration of the proximal screws is a commonly occurring outcome complication and the primary factor contributing to the need for remedial surgery [ 3 ]. To reduce the risk of such complications, the ALPS Proximal Humerus Plating System (Zimmer Biomet, Warsaw, IN, USA) has introduced blunt-tip pegs instead of conventional screws to fix the proximal fragment (Fig. 1 a). Recent comparative clinical studies of fixation using pegs and threaded screws have provided a clearer understanding of the surgical outcomes of plate fixation using proximal pegs for proximal humeral fractures [ 4 – 7 ]. However, in these studies, although the ALPS plate was used in the peg group, either the PHILOS plate [ 4 – 6 ] or the MODE plate [ 7 ] was utilized in the screw group, potentially introducing bias, owing to inter-group differences regarding plate design. To date, no direct comparison of proximal screws and pegs has been conducted within the same plate system; therefore, the isolated effect of proximal pegs on surgical outcomes remains largely unknown. This study aimed to compare the surgical outcomes of ALPS plate fixation using proximal pegs and proximal screws. Photograph of a proximal peg (left panel) and screw (right panel) (a). Postoperative radiographs of the patients who underwent plate fixation using ALPS plates fixed exclusively with proximal pegs (b) or screws (c). Methods Patient selection The study protocol was approved by the independent ethics committee of the hospital. This retrospective study was conducted at two hospitals from 2023 to 2025. During this period, an orthopedic surgeon with more than 10 years of experience in shoulder surgery performed osteosynthesis using the ALPS plate in all cases of Neer type two- or three-part proximal humeral fractures, with the exception of those patients with a high risk of postoperative humeral head necrosis (posteromedial metaphyseal head extension, disruption of the medial hinge) [ 8 ]. For fixation of the proximal fragment, in all cases pegs were used exclusively until January 2024, whereas from February 2024 to date, screws have been used in all cases. Here, adult patients with at least one year of postoperative follow-up were included. Patients with pathological fractures, multiple injuries, or isolated fractures of the lesser or greater tuberosity were excluded. Patients in the peg group partially overlapped with those included in a previous study [ 7 ]. Patients who had undergone surgery up until January 2024 and those who underwent surgery during February 2024 or thereafter were allocated to the peg and screw groups, respectively. Surgical procedure All patients underwent surgery under general anesthesia in the beach chair position. Using the deltopectoral approach, the fracture fragments were reduced using No. 2 FiberWire (Arthrex, Naples, FL, USA) attached to the supraspinatus and infraspinatus tendons. Reduction was performed until an anatomical or acceptable reduction status, as reported by Schnetzke et al. [ 9 ], was achieved under intraoperative fluoroscopy (OEC Elite; GE Healthcare, Chicago, IL, USA). In all cases, plate fixation was subsequently performed using a high ALPS plate. As many pegs and screws as possible (7–9 pegs/screws) were inserted into the proximal humeral fragments, whereas three screws were inserted into the distal humeral fragments. Finally, the FiberWire attached to the rotator cuff tendons was secured to the plate holes. Apart from these steps, there were no supplementary fixation procedures, such as bony allograft augmentation or insertion of additional calcar screws. Postoperative radiographs are shown in Fig. 1 b and 1 c. For the patients in both groups, passive range-of-motion training was initiated on postoperative day 3, with subsequent active range-of-motion training commencing at 4 weeks, followed by rotator cuff exercises at 8 weeks. Heavy labor was permitted at 3 months postoperatively and outpatient rehabilitation was performed after 5 months. Outcome measures As perioperative outcomes, we evaluated operative time, blood loss, and immediate reduction status [ 9 ] Furthermore, postoperative shoulder function was assessed at 1 year using the Constant score [ 10 ] and American Shoulder and Elbow Surgeons (ASES) Score [ 11 ]. Constant scores were adjusted for age and sex [ 12 ]. Range of motion was similarly assessed at 1 year postoperatively, measured by the operating surgeon or an assigned occupational therapist using a goniometer. In addition, postoperative complications (peg/screw penetration, avascular necrosis, varus progression, loss of greater tuberosity reduction, and revision surgery) were recorded within 1 year postoperatively. Complications were evaluated by a single assessor using historical clinical notes and plain radiographs, with the proximal peg/screw cut-out being evaluated in two directions on radiographs. A loss of reduction was defined as varus progression exceeding 10° at the head-shaft angle [ 13 ], whereas a loss of greater tuberosity reduction was defined as the apex of the greater tuberosity being less than 5 mm inferior to the apex of the humeral head on the anteroposterior radiograph in neutral rotation [ 14 ]. The efficacies of fixation performed for patients in the peg and screw groups were assessed based on the adjusted Constant scores, which served as the primary outcome. Statistical analysis All statistical analyses were conducted using SPSS software (version 27.0; IBM Corp., Armonk, NY, USA). The Shapiro–Wilk test was used to evaluate the normality of continuous variables. Student’s t -test was applied to compare mean values with a normal distribution (age and body mass index), whereas the Mann–Whitney U-test was used to compare non-normally distributed median values (days from injury to surgery, operative time, blood loss, adjusted Constant score, ASES score, and range of motion). Fisher’s exact test was used to compare proportions of categorical variables (sex, side of injury, smoking status, fracture type, presence of local osteoporosis, reduction status, and postoperative complications). The threshold for significance was set at P = 0.05. The minimum clinically important difference in the Constant score for patients with proximal humeral fractures was 11.6 [ 15 ]. Power analysis, assuming 0.80 power, a significance level of 0.05, and a standard deviation of 13.6 for the Constant score among patients who underwent ALPS plate fixation [ 6 ], indicated that 23 patients per group would be required to detect a clinically significant difference between groups with respect to postoperative Constant scores. Results Fifty-four patients (peg group, 26; screw group, 28) who met the inclusion and exclusion criteria were identified. No significant differences were observed between the two groups regarding age, sex, side of injury, BMI, smoking history, time from injury to surgery (days), local osteoporosis, or fracture type (Table 1 ). Table 1 Patient demographics Age (years) * Peg (n = 26) Screw (n = 28) P-value 67.6 ± 15.7 72.2 ± 11.1 0.23 Sex, Male/Female † 7/19 7/21 > 0.99 Side of injury, Right/Left † 11/15 9/19 0.57 Body mass index * 23.0 ± 4.5 23.6 ± 5.1 0.69 Smoking history † 5 5 > 0.99 Day from injury to surgery (days) * 5 (4–7) 7 (4–9) 0.13 Local osteoporosis † 12 17 0.41 Neer two-/three-part † 17/9 18/10 > 0.99 Medial comminution † 7 11 0.40 Varus displaced fracture † 15 18 0.78 * Continuous values with a normal distribution are presented as the mean ± standard deviation. Continuous values without a normal distribution are presented as the median (interquartile range). † Values are presented as the number of patients. No significant differences in surgical time, blood loss, or reduction status immediately after surgery were observed between the two groups (Table 2 ). Table 2 Comparison of operative factors Operative time * (minutes) Peg (n = 26) Screw (n = 28) P-value 95 [84–103] 82 [80–97] 0.16 Blood loss * (g) 100 [70–134] 100 [69–119] 0.70 Reduction status † 0.26 Anatomical 19 16 Acceptable 7 12 * Values are presented as the median [95% confidence interval]. † Values are presented as the number of patients. For shoulder functional scores, no significant differences in the mean adjusted Constant score, ASES score, or range of shoulder motion were observed between the two groups (Table 3 ). Table 3 Comparison of clinical outcome scores and range of shoulder motion Adjusted Constant score Peg (n = 26) Screw (n = 28) P-value 90 [81–97] 89 [81–92] 0.79 ASES score 86 [72–90] 82 [75–92] 0.99 Range of shoulder motion Anterior elevation (º) 150 [90–160] 142 [110–155] 0.83 External rotation at sides (º) 40 [40–50] 40 [30–45] 0.89 Values are presented as the median [95% confidence interval]. ASES = American Shoulder and Elbow Surgeons. Among postoperative complications, loss of greater tuberosity reduction was significantly more frequent in the peg group than in the screw group (23.1% vs. 3.6%, P = 0.047). Conversely, three patients in the screw group underwent revision surgery because of symptomatic proximal implant penetration and varus progression, whereas no patients in the peg group underwent revision surgery (Table 4 ). Table 4 Comparison of postoperative complication rates Nonunion Peg (n = 26) Screw (n = 28) P-value 0 (0%) 0 (0%) > 0.99 Screw/peg penetration 2 (7.7%) 3 (10.7%) > 0.99 Avascular necrosis 0 (0%) 0 (0%) > 0.99 Varus progression 3 (11.5%) 6 (21.4%) 0.47 Greater tuberosity reduction loss 6 (23.1%) 1 (3.6%) 0.047* Revision surgery 0 (0%) 3 (10.7%) 0.24 Values are presented as the number of patients (percentage). * P < 0.05 Discussion In this study, we compared the surgical outcomes of ALPS plate fixation using proximal pegs and screws for proximal humeral fracture. Three important clinical observations were made. Firstly, our findings indicate that the use of proximal pegs had no significant influence regarding postoperative shoulder functional outcome scores or the incidence of postoperative proximal implant penetration and varus progression. These results concur with those of previous clinical studies reporting no significant differences in postoperative outcomes between the peg and screw groups [ 4 – 7 ]. Previous biomechanical studies [ 16 , 17 ] have revealed no significant differences between the biomechanical properties of proximal pegs and proximal screws used for plate fixation in a two-part proximal humeral fracture model, which may explain the absence of differences in the incidence of proximal humeral head fixation failure in this study. Collectively, these findings indicate that proximal pegs could serve as an effective alternative to screws for two-part proximal humeral fractures. Secondly, in this study, we found that the use of proximal pegs was associated with a significantly higher frequency of greater tuberosity reduction loss than that achieved using proximal screws. This finding is consistent with previous findings, which indicate a tendency toward greater postoperative tuberosity displacement in the peg group than in the screw group [ 4 , 7 ]. These previous studies suggested that the ALPS plate design, with less coverage of the greater tuberosity, may lead to a higher incidence of greater tuberosity reduction loss [ 4 , 7 ]. Nonetheless, because the same plate system was used here, the difference in fixation between pegs and screws significantly influenced the occurrence of this complication. Smooth pegs are designed to enhance subchondral support, offering the advantage of closer placement to the subchondral surface without thread penetration into the glenohumeral joint, whereas conventional threaded locking screws enable direct fixation of bone fragments [ 18 ]. Nevertheless, previous biomechanical studies comparing proximal pegs and screws for proximal humeral fractures included only two-part fractures, rather than three-part fractures involving the greater tuberosity fragment [ 16 , 17 , 19 ], leaving the underlying cause of this finding unclear. In distal radius fracture models, threaded screws demonstrated greater biomechanical properties than smooth pegs for fixation of small dorsal lunate fragments [ 20 ] or comminuted fragments [ 18 ], raising the possibility that threaded screws may offer advantages for fixing small comminuted bone fragments. This may have contributed to the difference in postoperative greater tuberosity displacement between the two groups. Reduction loss of the greater tuberosity is associated with poor functional outcomes [ 7 , 14 , 21 , 22 ]; therefore, the use of threaded screws is desirable for three-part fractures involving the greater tuberosity. Thirdly, we found that none of patients in the peg group required revision surgery on account of symptomatic implant perforation or varus progression. Although smooth pegs were developed to reduce the risk of peg penetration, the present research and previous clinical studies have demonstrated no significant differences in the incidence of screw and peg penetration [ 4 – 7 ]. Nonetheless, because patients in the peg group with postoperative peg penetration exhibited no symptoms requiring surgery, peg use may reduce intra-articular damage, even if penetration occurs [ 23 ]. This study has two major strengths. First, it is the first comparative study to use the same plate system, including proximal pegs and screws, thereby reducing bias arising from differences in plate design. Second, all patients included in this study underwent surgery performed by the same surgeon using the same approach, technique, and postoperative rehabilitation protocols, thereby minimizing the influence of surgical technique and rehabilitation variability on surgical outcomes. Nevertheless, this study had some limitations. First, this was a retrospective cohort study; therefore, bias from unobserved differences may have influenced the outcomes. Second, surgical outcomes were evaluated at 1 year postoperatively, and long-term outcomes were not assessed. Third, the sample size was sufficient to compare functional outcome scores; nonetheless, a power analysis assuming a 42% rate of radiological complications [ 24 ] shows that 52 patients per group was required to detect a 25% difference in the postoperative complication rate. Thus, statistical analysis of the postoperative complication rate may have been influenced by unmeasured factors. Conclusions This study offers novel insights into the influence of distinct proximal implants on the surgical outcomes of plate fixation for proximal humeral fractures. The use of a proximal peg rather than a screw did not significantly affect postoperative functional outcomes, although no reoperation was required in the peg group. Nevertheless, proximal threaded screws are recommended for three-part fractures to reduce the risk of greater tuberosity loss. Abbreviations ASES American Shoulder and Elbow Surgeons BMI body mass index Declarations Ethical approval and consent to participate: This study was approved by the Independent Ethics Committee of the Ashikaga Red Cross Hospital (No. 2022-27). This retrospective study was conducted in accordance with the principles of the Declaration of Helsinki. Opt-out consent is based on implicit consent, in which willingness to participate is tacit or presumed and can be withdrawn through active objection. Consent for publication: Not applicable Competing Interests: The authors declare that they have no competing interests. Funding: The authors certify that they or their institutions received no support (e.g., grants, funding, payment, or other benefits), and had no commitment or agreement to provide such benefits, in connection with the research or preparation of this manuscript. No funding was received for the study design; data collection, analysis, and interpretation; or manuscript writing. Author Contribution RF: Conceptualization, Data curation, Writing-original draftAT: Data curation, Project administrationSO: Data curation, Writing-review & editingNM: Project administration, Writing-review & editing Acknowledgments: Not applicable. Data Availability Data supporting the findings of this study are available from the corresponding author upon reasonable request. References Sproul RC, Iyengar JJ, Devcic Z, Feeley BT. A systematic review of locking plate fixation of proximal humerus fractures. Injury. 2011;42(4):408–13. 10.1016/j.injury.2010.11.058 . Panagiotopoulou VC, Varga P, Richards RG, Gueorguiev B, Giannoudis PV. Late screw-related complications in locking plating of proximal humerus fractures: a systematic review. Injury. 2019;50(12):2176–95. 10.1016/j.injury.2019.11.002 . Thanasas C, Kontakis G, Angoules A, Limb D, Giannoudis P. Treatment of proximal humerus fractures with locking plates: a systematic review. 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Effect of osteoporosis on proximal humerus fractures. Geriatr Orthop Surg Rehabil. 2020;11:2151459320985399. 10.1177/2151459320985399 . Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 10 May, 2026 Reviewers agreed at journal 30 Apr, 2026 Reviewers invited by journal 20 Mar, 2026 Editor invited by journal 10 Mar, 2026 Editor assigned by journal 09 Mar, 2026 Submission checks completed at journal 09 Mar, 2026 First submitted to journal 09 Mar, 2026 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. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9071472","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":610156936,"identity":"2133f2bf-7066-479c-a6e8-3df8dbf08635","order_by":0,"name":"Ryogo Furuhata","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABCUlEQVRIiWNgGAWjYNACngQGBgnGBmYGBhsgj7HxAGEtMnAtaSAtDURosQFpYWAAajkM5uPVYj4j+fCLDzlpcubSzc2fC2rO261tPwy0pcYmGqeTbqSlWc44k2NsOedgm/SMY7eTt51JBGo5lpbbgEOLhESOmTFvT0XihhuJbcw8bLeTzQ4AtTA2HCag5V9FPVBL82eef+eSzc4/JKjF+DEPT06CwY3EBmnetgN2ZjcI2cLzLI1xBk+a4YY7QL/w9iUnmN0A2pKAzy/syYc/fOBJlje43f74M883O3uz8+kPH3yoscGphUEggU0CmZ8IVpmASzkI8B9g/oDMt8eneBSMglEwCkYmAABzbmWmOHNtMgAAAABJRU5ErkJggg==","orcid":"","institution":"Ashikaga Red Cross Hospital","correspondingAuthor":true,"prefix":"","firstName":"Ryogo","middleName":"","lastName":"Furuhata","suffix":""},{"id":610156937,"identity":"6e96c15f-d781-4267-ae44-2d674f4ef48a","order_by":1,"name":"Atsushi Tanji","email":"","orcid":"","institution":"Ashikaga Red Cross Hospital","correspondingAuthor":false,"prefix":"","firstName":"Atsushi","middleName":"","lastName":"Tanji","suffix":""},{"id":610156938,"identity":"e7180eee-ae7b-4aac-815b-9369a69afb72","order_by":2,"name":"Satoshi Oki","email":"","orcid":"","institution":"Keio University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Satoshi","middleName":"","lastName":"Oki","suffix":""},{"id":610156939,"identity":"56dc7ebb-a77b-4267-9c25-73e52940f19d","order_by":3,"name":"Noboru Matsumura","email":"","orcid":"","institution":"Keio University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Noboru","middleName":"","lastName":"Matsumura","suffix":""}],"badges":[],"createdAt":"2026-03-09 10:08:35","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9071472/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9071472/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":105409866,"identity":"a4f99ecf-1b2b-4ed1-9aa4-652c6ed327d6","added_by":"auto","created_at":"2026-03-25 17:11:02","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":602100,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ePhotograph and clinical images of fixationusing ALPS plates with pegs and screws.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePhotograph of a proximal peg (left panel) and screw (right panel) (a).Postoperative radiographs of the patients who underwent plate fixation using ALPS plates fixed exclusively with proximal pegs (b) or screws (c).\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-9071472/v1/7c7fc7e9bc1fb3befb65d25b.png"},{"id":105409886,"identity":"45799cfc-a712-4ae6-a7b3-e12da88fbbc6","added_by":"auto","created_at":"2026-03-25 17:11:07","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1502477,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9071472/v1/82707b39-cb77-44fb-bf1b-1ada4281c8a2.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Effects of proximal smooth pegs on surgical outcomes of plate fixation for proximal humeral fractures","fulltext":[{"header":"Introduction","content":"\u003cp\u003eLocking plate-mediated osteosynthesis is a widely used surgical technique for the treatment of proximal humeral fractures. Nonetheless, a relatively high postoperative complication rate has been reported [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], among which, intra-articular penetration of the proximal screws is a commonly occurring outcome complication and the primary factor contributing to the need for remedial surgery [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. To reduce the risk of such complications, the ALPS Proximal Humerus Plating System (Zimmer Biomet, Warsaw, IN, USA) has introduced blunt-tip pegs instead of conventional screws to fix the proximal fragment (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e1\u003c/span\u003ea). Recent comparative clinical studies of fixation using pegs and threaded screws have provided a clearer understanding of the surgical outcomes of plate fixation using proximal pegs for proximal humeral fractures [\u003cspan additionalcitationids=\"CR5 CR6\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. However, in these studies, although the ALPS plate was used in the peg group, either the PHILOS plate [\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e] or the MODE plate [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e] was utilized in the screw group, potentially introducing bias, owing to inter-group differences regarding plate design. To date, no direct comparison of proximal screws and pegs has been conducted within the same plate system; therefore, the isolated effect of proximal pegs on surgical outcomes remains largely unknown.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThis study aimed to compare the surgical outcomes of ALPS plate fixation using proximal pegs and proximal screws.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003ePhotograph of a proximal peg (left panel) and screw (right panel) (a). Postoperative radiographs of the patients who underwent plate fixation using ALPS plates fixed exclusively with proximal pegs (b) or screws (c).\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePatient selection\u003c/h2\u003e \u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003e The study protocol was approved by the independent ethics committee of the hospital.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eThis retrospective study was conducted at two hospitals from 2023 to 2025. During this period, an orthopedic surgeon with more than 10 years of experience in shoulder surgery performed osteosynthesis using the ALPS plate in all cases of Neer type two- or three-part proximal humeral fractures, with the exception of those patients with a high risk of postoperative humeral head necrosis (posteromedial metaphyseal head extension, disruption of the medial hinge) [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. For fixation of the proximal fragment, in all cases pegs were used exclusively until January 2024, whereas from February 2024 to date, screws have been used in all cases.\u003c/p\u003e \u003cp\u003eHere, adult patients with at least one year of postoperative follow-up were included. Patients with pathological fractures, multiple injuries, or isolated fractures of the lesser or greater tuberosity were excluded. Patients in the peg group partially overlapped with those included in a previous study [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e \u003cp\u003ePatients who had undergone surgery up until January 2024 and those who underwent surgery during February 2024 or thereafter were allocated to the peg and screw groups, respectively.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eSurgical procedure\u003c/h3\u003e\n\u003cp\u003eAll patients underwent surgery under general anesthesia in the beach chair position. Using the deltopectoral approach, the fracture fragments were reduced using No. 2 FiberWire (Arthrex, Naples, FL, USA) attached to the supraspinatus and infraspinatus tendons. Reduction was performed until an anatomical or acceptable reduction status, as reported by Schnetzke et al. [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e], was achieved under intraoperative fluoroscopy (OEC Elite; GE Healthcare, Chicago, IL, USA). In all cases, plate fixation was subsequently performed using a high ALPS plate. As many pegs and screws as possible (7\u0026ndash;9 pegs/screws) were inserted into the proximal humeral fragments, whereas three screws were inserted into the distal humeral fragments. Finally, the FiberWire attached to the rotator cuff tendons was secured to the plate holes. Apart from these steps, there were no supplementary fixation procedures, such as bony allograft augmentation or insertion of additional calcar screws. Postoperative radiographs are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e1\u003c/span\u003eb and \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e1\u003c/span\u003ec. For the patients in both groups, passive range-of-motion training was initiated on postoperative day 3, with subsequent active range-of-motion training commencing at 4 weeks, followed by rotator cuff exercises at 8 weeks. Heavy labor was permitted at 3 months postoperatively and outpatient rehabilitation was performed after 5 months.\u003c/p\u003e\n\u003ch3\u003eOutcome measures\u003c/h3\u003e\n\u003cp\u003eAs perioperative outcomes, we evaluated operative time, blood loss, and immediate reduction status [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e] Furthermore, postoperative shoulder function was assessed at 1 year using the Constant score [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e] and American Shoulder and Elbow Surgeons (ASES) Score [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Constant scores were adjusted for age and sex [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Range of motion was similarly assessed at 1 year postoperatively, measured by the operating surgeon or an assigned occupational therapist using a goniometer. In addition, postoperative complications (peg/screw penetration, avascular necrosis, varus progression, loss of greater tuberosity reduction, and revision surgery) were recorded within 1 year postoperatively. Complications were evaluated by a single assessor using historical clinical notes and plain radiographs, with the proximal peg/screw cut-out being evaluated in two directions on radiographs. A loss of reduction was defined as varus progression exceeding 10\u0026deg; at the head-shaft angle [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e], whereas a loss of greater tuberosity reduction was defined as the apex of the greater tuberosity being less than 5 mm inferior to the apex of the humeral head on the anteroposterior radiograph in neutral rotation [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe efficacies of fixation performed for patients in the peg and screw groups were assessed based on the adjusted Constant scores, which served as the primary outcome.\u003c/p\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eAll statistical analyses were conducted using SPSS software (version 27.0; IBM Corp., Armonk, NY, USA). The Shapiro\u0026ndash;Wilk test was used to evaluate the normality of continuous variables. Student\u0026rsquo;s \u003cem\u003et\u003c/em\u003e-test was applied to compare mean values with a normal distribution (age and body mass index), whereas the Mann\u0026ndash;Whitney U-test was used to compare non-normally distributed median values (days from injury to surgery, operative time, blood loss, adjusted Constant score, ASES score, and range of motion). Fisher\u0026rsquo;s exact test was used to compare proportions of categorical variables (sex, side of injury, smoking status, fracture type, presence of local osteoporosis, reduction status, and postoperative complications). The threshold for significance was set at P\u0026thinsp;=\u0026thinsp;0.05.\u003c/p\u003e \u003cp\u003eThe minimum clinically important difference in the Constant score for patients with proximal humeral fractures was 11.6 [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Power analysis, assuming 0.80 power, a significance level of 0.05, and a standard deviation of 13.6 for the Constant score among patients who underwent ALPS plate fixation [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e], indicated that 23 patients per group would be required to detect a clinically significant difference between groups with respect to postoperative Constant scores.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eFifty-four patients (peg group, 26; screw group, 28) who met the inclusion and exclusion criteria were identified. No significant differences were observed between the two groups regarding age, sex, side of injury, BMI, smoking history, time from injury to surgery (days), local osteoporosis, or fracture type (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\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\u003ePatient demographics\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=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" 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\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eAge (years) *\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePeg (n\u0026thinsp;=\u0026thinsp;26)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eScrew (n\u0026thinsp;=\u0026thinsp;28)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e67.6\u0026thinsp;\u0026plusmn;\u0026thinsp;15.7\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e72.2\u0026thinsp;\u0026plusmn;\u0026thinsp;11.1\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.23\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex, Male/Female \u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7/19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7/21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;0.99\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSide of injury, Right/Left \u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11/15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9/19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.57\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBody mass index *\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23.0\u0026thinsp;\u0026plusmn;\u0026thinsp;4.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23.6\u0026thinsp;\u0026plusmn;\u0026thinsp;5.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.69\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSmoking history \u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;0.99\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDay from injury to surgery (days) *\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (4\u0026ndash;7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7 (4\u0026ndash;9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.13\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLocal osteoporosis \u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.41\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNeer two-/three-part \u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e17/9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18/10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;0.99\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMedial comminution \u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.40\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVarus displaced fracture \u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.78\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* Continuous values with a normal distribution are presented as the mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation. Continuous values without a normal distribution are presented as the median (interquartile range). \u0026dagger; Values are presented as the number of patients.\u003c/p\u003e \u003cp\u003eNo significant differences in surgical time, blood loss, or reduction status immediately after surgery were observed between the two groups (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\u003eComparison of operative factors\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=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" 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\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eOperative time * (minutes)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePeg (n\u0026thinsp;=\u0026thinsp;26)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eScrew (n\u0026thinsp;=\u0026thinsp;28)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e95 [84\u0026ndash;103]\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e82 [80\u0026ndash;97]\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.16\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood loss * (g)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e100 [70\u0026ndash;134]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100 [69\u0026ndash;119]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.70\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eReduction status \u0026dagger;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.26\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnatomical\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAcceptable\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e* Values are presented as the median [95% confidence interval]. \u0026dagger; Values are presented as the number of patients.\u003c/p\u003e \u003cp\u003eFor shoulder functional scores, no significant differences in the mean adjusted Constant score, ASES score, or range of shoulder motion were observed between the two groups (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of clinical outcome scores and range of shoulder motion\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=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" 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\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eAdjusted Constant score\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePeg (n\u0026thinsp;=\u0026thinsp;26)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eScrew (n\u0026thinsp;=\u0026thinsp;28)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e90 [81\u0026ndash;97]\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e89 [81\u0026ndash;92]\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.79\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eASES score\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e86 [72\u0026ndash;90]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e82 [75\u0026ndash;92]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.99\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRange of shoulder motion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior elevation (\u0026ordm;)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e150 [90\u0026ndash;160]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e142 [110\u0026ndash;155]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.83\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eExternal rotation at sides (\u0026ordm;)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e40 [40\u0026ndash;50]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e40 [30\u0026ndash;45]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.89\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\u003eValues are presented as the median [95% confidence interval]. ASES\u0026thinsp;=\u0026thinsp;American Shoulder and Elbow Surgeons.\u003c/p\u003e \u003cp\u003eAmong postoperative complications, loss of greater tuberosity reduction was significantly more frequent in the peg group than in the screw group (23.1% vs. 3.6%, P\u0026thinsp;=\u0026thinsp;0.047). Conversely, three patients in the screw group underwent revision surgery because of symptomatic proximal implant penetration and varus progression, whereas no patients in the peg group underwent revision surgery (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of postoperative complication rates\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=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" 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\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eNonunion\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePeg (n\u0026thinsp;=\u0026thinsp;26)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eScrew (n\u0026thinsp;=\u0026thinsp;28)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;0.99\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eScrew/peg penetration\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 (7.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (10.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;0.99\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAvascular necrosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;0.99\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVarus progression\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (11.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6 (21.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.47\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGreater tuberosity reduction loss\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6 (23.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (3.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.047*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRevision surgery\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (10.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.24\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\u003eValues are presented as the number of patients (percentage). * P\u0026thinsp;\u0026lt;\u0026thinsp;0.05\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this study, we compared the surgical outcomes of ALPS plate fixation using proximal pegs and screws for proximal humeral fracture. Three important clinical observations were made.\u003c/p\u003e \u003cp\u003eFirstly, our findings indicate that the use of proximal pegs had no significant influence regarding postoperative shoulder functional outcome scores or the incidence of postoperative proximal implant penetration and varus progression. These results concur with those of previous clinical studies reporting no significant differences in postoperative outcomes between the peg and screw groups [\u003cspan additionalcitationids=\"CR5 CR6\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Previous biomechanical studies [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e] have revealed no significant differences between the biomechanical properties of proximal pegs and proximal screws used for plate fixation in a two-part proximal humeral fracture model, which may explain the absence of differences in the incidence of proximal humeral head fixation failure in this study. Collectively, these findings indicate that proximal pegs could serve as an effective alternative to screws for two-part proximal humeral fractures.\u003c/p\u003e \u003cp\u003eSecondly, in this study, we found that the use of proximal pegs was associated with a significantly higher frequency of greater tuberosity reduction loss than that achieved using proximal screws. This finding is consistent with previous findings, which indicate a tendency toward greater postoperative tuberosity displacement in the peg group than in the screw group [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. These previous studies suggested that the ALPS plate design, with less coverage of the greater tuberosity, may lead to a higher incidence of greater tuberosity reduction loss [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Nonetheless, because the same plate system was used here, the difference in fixation between pegs and screws significantly influenced the occurrence of this complication. Smooth pegs are designed to enhance subchondral support, offering the advantage of closer placement to the subchondral surface without thread penetration into the glenohumeral joint, whereas conventional threaded locking screws enable direct fixation of bone fragments [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Nevertheless, previous biomechanical studies comparing proximal pegs and screws for proximal humeral fractures included only two-part fractures, rather than three-part fractures involving the greater tuberosity fragment [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e], leaving the underlying cause of this finding unclear. In distal radius fracture models, threaded screws demonstrated greater biomechanical properties than smooth pegs for fixation of small dorsal lunate fragments [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] or comminuted fragments [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e], raising the possibility that threaded screws may offer advantages for fixing small comminuted bone fragments. This may have contributed to the difference in postoperative greater tuberosity displacement between the two groups. Reduction loss of the greater tuberosity is associated with poor functional outcomes [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]; therefore, the use of threaded screws is desirable for three-part fractures involving the greater tuberosity.\u003c/p\u003e \u003cp\u003eThirdly, we found that none of patients in the peg group required revision surgery on account of symptomatic implant perforation or varus progression. Although smooth pegs were developed to reduce the risk of peg penetration, the present research and previous clinical studies have demonstrated no significant differences in the incidence of screw and peg penetration [\u003cspan additionalcitationids=\"CR5 CR6\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Nonetheless, because patients in the peg group with postoperative peg penetration exhibited no symptoms requiring surgery, peg use may reduce intra-articular damage, even if penetration occurs [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThis study has two major strengths. First, it is the first comparative study to use the same plate system, including proximal pegs and screws, thereby reducing bias arising from differences in plate design. Second, all patients included in this study underwent surgery performed by the same surgeon using the same approach, technique, and postoperative rehabilitation protocols, thereby minimizing the influence of surgical technique and rehabilitation variability on surgical outcomes.\u003c/p\u003e \u003cp\u003eNevertheless, this study had some limitations. First, this was a retrospective cohort study; therefore, bias from unobserved differences may have influenced the outcomes. Second, surgical outcomes were evaluated at 1 year postoperatively, and long-term outcomes were not assessed. Third, the sample size was sufficient to compare functional outcome scores; nonetheless, a power analysis assuming a 42% rate of radiological complications [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e] shows that 52 patients per group was required to detect a 25% difference in the postoperative complication rate. Thus, statistical analysis of the postoperative complication rate may have been influenced by unmeasured factors.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThis study offers novel insights into the influence of distinct proximal implants on the surgical outcomes of plate fixation for proximal humeral fractures. The use of a proximal peg rather than a screw did not significantly affect postoperative functional outcomes, although no reoperation was required in the peg group. Nevertheless, proximal threaded screws are recommended for three-part fractures to reduce the risk of greater tuberosity loss.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eASES\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eAmerican Shoulder and Elbow Surgeons\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eBMI\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ebody mass index\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003cstrong\u003eEthical approval and consent to participate:\u003c/strong\u003e \u003cp\u003eThis study was approved by the Independent Ethics Committee of the Ashikaga Red Cross Hospital (No. 2022-27). This retrospective study was conducted in accordance with the principles of the Declaration of Helsinki. Opt-out consent is based on implicit consent, in which willingness to participate is tacit or presumed and can be withdrawn through active objection.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eConsent for publication:\u003c/strong\u003e \u003cp\u003eNot applicable\u003c/p\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eCompeting Interests:\u003c/h2\u003e \u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding:\u003c/h2\u003e \u003cp\u003eThe authors certify that they or their institutions received no support (e.g., grants, funding, payment, or other benefits), and had no commitment or agreement to provide such benefits, in connection with the research or preparation of this manuscript. No funding was received for the study design; data collection, analysis, and interpretation; or manuscript writing.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eRF: Conceptualization, Data curation, Writing-original draftAT: Data curation, Project administrationSO: Data curation, Writing-review \u0026amp; editingNM: Project administration, Writing-review \u0026amp; editing\u003c/p\u003e\u003ch2\u003eAcknowledgments:\u003c/h2\u003e \u003cp\u003eNot applicable.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eData supporting the findings of this study are available from the corresponding author upon reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eSproul RC, Iyengar JJ, Devcic Z, Feeley BT. A systematic review of locking plate fixation of proximal humerus fractures. 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Geriatr Orthop Surg Rehabil. 2020;11:2151459320985399. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1177/2151459320985399\u003c/span\u003e\u003cspan address=\"10.1177/2151459320985399\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-musculoskeletal-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmsd","sideBox":"Learn more about [BMC Musculoskeletal Disorders](http://bmcmusculoskeletdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://author-welcome.nature.com/12891","title":"BMC Musculoskeletal Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"proximal humeral fracture, plate fixation, outcome, peg, screw","lastPublishedDoi":"10.21203/rs.3.rs-9071472/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9071472/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003ePlate fixation yields satisfactory functional outcomes in proximal humeral fractures; nonetheless, a relatively high complication rate has been reported. Smooth pegs were introduced to reduce proximal screw cut-out. However, no direct comparison has been performed between proximal pegs and screws within the same plate system. This study aimed to compare the surgical outcomes of osteosynthesis with ALPS plates featuring proximal pegs and screws.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eFifty-four patients who had undergone plate fixation for proximal humeral fractures were retrospectively identified. All operations were performed by the same surgeon using a deltopectoral approach. Whereas ALPS plates fixed exclusively with proximal pegs were used prior to January 2024 (peg group, 26 patients), those with exclusive proximal screw fixation were used after February 2024 (screw group, 28 patients). As an outcome measure, we assessed postoperative shoulder functional scores and compared the two groups regarding the respective rates of complication.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eAt 1 year postoperatively, no significant between-group differences were observed in the adjusted Constant and American Shoulder and Elbow Surgeons scores. Nonetheless, the incidence of loss of greater tuberosity reduction was significantly higher in the peg group than in the screw group (23.1% vs. 3.6%, P\u0026thinsp;=\u0026thinsp;0.047). Conversely, three patients required revision surgery because of symptomatic proximal implant penetration or varus progression in the screw group, whereas no patients required reoperation in the peg group.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eThe use of proximal pegs rather than screws did not significantly affect postoperative functional outcomes, although reoperation was not required in the peg group. Nevertheless, proximal threaded screws are recommended for three-part fractures to reduce the risk of secondary displacement of the greater tuberosity.\u003c/p\u003e\u003ch2\u003eTrial registration:\u003c/h2\u003e \u003cp\u003eNot applicable.\u003c/p\u003e","manuscriptTitle":"Effects of proximal smooth pegs on surgical outcomes of plate fixation for proximal humeral fractures","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-25 17:10:00","doi":"10.21203/rs.3.rs-9071472/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"230272973067499372449015208119598873308","date":"2026-05-10T13:43:13+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"311071648616692163595895287705274165011","date":"2026-04-30T14:26:20+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-20T12:35:36+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-03-10T10:57:57+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-10T03:34:25+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-10T03:33:41+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Musculoskeletal Disorders","date":"2026-03-09T10:00:01+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-musculoskeletal-disorders","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmsd","sideBox":"Learn more about [BMC Musculoskeletal Disorders](http://bmcmusculoskeletdisord.biomedcentral.com/)","snPcode":"","submissionUrl":"https://author-welcome.nature.com/12891","title":"BMC Musculoskeletal Disorders","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"0ceeb45a-92a1-4d0c-9ec7-4f2d821e1f02","owner":[],"postedDate":"March 25th, 2026","published":true,"recentEditorialEvents":[{"type":"reviewerAgreed","content":"230272973067499372449015208119598873308","date":"2026-05-10T13:43:13+00:00","index":71,"fulltext":""},{"type":"reviewerAgreed","content":"311071648616692163595895287705274165011","date":"2026-04-30T14:26:20+00:00","index":55,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-03-25T17:10:00+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-25 17:10:00","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9071472","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9071472","identity":"rs-9071472","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}