Abstract
Purpose:
This analysis seeks to clarify the clinical efficacy of each treatment modality and inform evidence-based decision-making in the management of this common yet complex injury.
Methods:
A comprehensive systematic search was performed across major medical databases, including Medline (PubMed), Scopus, Web of Science, Embase, The Cochrane Library, ClinicalTrials.gov, and CINAHL Ultimate, to identify studies addressing the outcomes of treatment for primary medial epicondyle fractures.
Results:
A total of 65 studies published between 1982 and 2026 were included in the meta-analysis. The pooled incidence of fracture union rate following surgical treatment was 97% (95% confidence interval (CI): 95%–98%). Conservative immobilization resulted in a markedly lower union rate of 46% (95% CI: 20%–74%). The overall complication rate following surgical treatment was 21% (95% CI: 16%–27%), compared to 36% (95% CI: 13%–63%) for conservative immobilization.
Conclusion:
Among surgical options, screw fixation was associated with high union rate and the lowest complication profile, with statistically distinct pooled estimates supporting its reliability in achieving stable healing and early mobilization. We believe that the pooled estimates from our study will be valuable in guiding clinical decision-making and will help assess the risk of potential outcomes and complications in patients with medial epicondyle fractures.
Significance of Study:
This study provides high-quality pooled evidence comparing surgical and conservative management of medial epicondyle fractures, helping clinicians make more informed, evidence-based decisions by clarifying differences in union rates, functional outcomes, and complication risks.
Introduction
Fractures of the medial epicondyle are among the most frequent elbow injuries in the pediatric and adolescent population, accounting for 11%–20% of all elbow fractures.1,2 These injuries occur most frequently in active children aged 9–14 years, often resulting from valgus stress applied to the elbow during a fall on the outstretched arm or following avulsion by the common flexor–pronator mass. 3 Due to their proximity to key anatomical structures, including the medial collateral ligament complex and the ulnar nerve, these fractures carry important functional implications for elbow stability and neurovascular integrity. 4
The optimal management of medial epicondylar fractures remains controversial. While nonoperative treatment with immobilization has long been the standard of care for minimally displaced injuries,1,5 growing concern regarding nonunion, valgus instability, chronic pain, and ulnar neuropathy has led many authors to advocate for open reduction and internal fixation (ORIF). 3 ORIF, most commonly performed using screws or K-wires, enables anatomical reduction and early mobilization; however, it is associated with complications such as hardware irritation, infection, and postoperative stiffness. 1 Importantly, despite decades of experience, the indications for operative intervention remain inconsistently defined, with decision-making often guided by fracture displacement thresholds, elbow stability under valgus stress, and the presence of ulnar nerve symptoms rather than uniform criteria. 1
Given the heterogeneity of existing literature and the lack of consensus regarding the relative benefits and risks of operative versus conservative management, a quantitative synthesis of current evidence is warranted. The aim of this study was to systematically review and meta-analyze clinical outcomes of primary medial epicondylar fracture management, comparing surgical and nonoperative approaches with respect to fracture union, range of motion (ROM), functional recovery, and complication rates. This analysis seeks to clarify the clinical efficacy of each treatment modality and inform evidence-based decision-making in the management of this common yet complex injury.
Methods
The study protocol was registered on the International Prospective Register of Systematic Reviews (PROSPERO registration number CRD420251020265, titled “Management of the Medial Epicondylar Fractures – A Systematic Review with Meta-analysis”). 6
Search strategy
A comprehensive systematic search was performed across major medical databases, including Medline (PubMed), Scopus, Web of Science, Embase, The Cochrane Library, ClinicalTrials.gov, and CINAHL Ultimate, to identify studies addressing the outcomes of treatment for primary medial epicondyle fractures. The search was conducted in three stages: (1) Initially, all the aforementioned databases were searched twice using the following search terms: (medial*) AND (epicondy*) AND (fracture*). (2) To reduce potential selection bias and ensure that no relevant publications were omitted, additional searches limited to titles and abstracts were carried out in each database. (3) In the final stage, the reference lists of all previously identified papers were manually screened for further eligible studies. The search terms were adapted for each phase and database. The complete search strategy is presented in Supplemental Table 1. At this stage, no restrictions regarding publication date, language, article type, or text availability were applied. The systematic search ended in May 2026 and included studies published up to April 2026. All databases were systematically searched by two authors working independently to ensure accuracy and consistency (MiB and IJ). During the study, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. 7
Study selection
The inclusion criteria covered randomized controlled trials, retrospective and prospective cohort studies, and case series that reported extractable numerical data on clinical outcomes of treatment for primary medial epicondyle fractures. Exclusion criteria comprised case reports, case series including fewer than three participants, conference abstracts, review articles, letters to the editor, studies published in languages other than English, studies presenting incomplete, imprecise, or irrelevant data, and studies with critical risk-of-bias. Any discrepancies in study selection were resolved through discussion among the authors. The process of study inclusion is illustrated in Figure 1.
Flow diagram presenting process of collecting data included in this meta-analysis.
Data extraction
Data extraction from all eligible studies was independently performed by two authors (MiB and JaW). The qualitative variables collected included publication year, geographical region, details of the treatment approach, and other relevant characteristics of the study populations. Quantitative data were also extracted, with particular emphasis on sample size, patient age, fracture union rate, ROM, outcome measures assessed with standardized scales, and complication rates. Any inconsistencies identified by the two reviewers were addressed by contacting the original study authors when possible or resolved through discussion and consensus with the remaining co-authors.
Risk-of-bias assessment
Risk-of-bias assessment of the included studies was performed by two independent authors (MiB and PO) using the ROBINS-I V2 and RoB2 tools (Supplemental Table 2).8,9 Any discrepancies in assessment were resolved through discussion and consensus with the remaining co-authors. Most studies demonstrated a moderate overall risk-of-bias, primarily related to confounding factors, while other domains generally showed low risk. Only a few studies were rated as having a serious risk-of-bias. Two studies were secondarily excluded due to a critical risk-of-bias. In addition, potential publication bias within each analyzed category was examined using Funnel plots, Doi plots, and the LFK index. 10 Owing to journal space limitations, the full set of Forest, Funnel, and Doi plots generated for each analysis is available upon request from the corresponding author. The obtained risk-of-bias ratings were incorporated into the interpretation of individual study results.
Statistical analysis
To perform the meta-analyses, STATISTICA version 14.1 software (StatSoft Inc., Tulsa, OK, USA), MetaXL version 5.3 software (EpiGear International Pty Ltd., Wilston, QLD, Australia), and Comprehensive Meta-analysis version 4.0 software (Biostat Inc., Englewood, NJ, USA) were used. All analyses were conducted using a random-effects model. Heterogeneity across studies was assessed using both Cochran’s Q test and the I2 statistic. 11 A p-value of <0.05 and 95% confidence intervals (CI) were used to identify statistically significant differences between groups. When confidence intervals overlapped, the differences were considered statistically insignificant.
Results
Search results
A total of 65 studies published between 1982 and 2026 were included in the meta-analysis.1,3,5,12–73 The studies collectively analyzed over 2000 pediatric and adolescent patients treated for primary medial epicondyle fractures across 5 continents, with the highest activity observed in North America (USA) and Asia (China, South Korea). The mean age of the patients ranged from 7 to 15 years, and males predominated across nearly all cohorts. ORIF using K-wires or screws was the most frequently applied surgical technique, while immobilization represented the conservative approach. Detailed characteristics of the included studies are presented in Table 1.
Characteristics of the studies included in this meta-analysis.
R: range; ORIF: open reduction internal fixation.
Fracture union rate
The pooled fracture union rate following surgical treatment was 97% (95% CI: 95%–98%), confirming the high reliability of operative management in achieving bony healing (Figure 2). Among fixation methods, K-wire fixation and screw fixation demonstrated comparable union rates of 95% (95% CI: 87%–99% and 92%–98%, respectively), with no clinically meaningful difference between techniques. In contrast, conservative immobilization resulted in a markedly lower union rate of 46% (95% CI: 20%–74%). These results suggest that surgical fixation offers a clear clinical advantage in achieving solid bone healing, potentially reducing the risk of delayed union or nonunion in growing patients. Detailed results are presented in Table 2.
Forrest plot regarding the fracture complete union rate union rate after treatment for primary medial epicondyle fractures in the overall surgical group. The overall surgical group comprises all procedures involving open reduction and internal fixation, regardless of the specific technique applied. The authors classified both bony and fibrous unions into the union group, while nonunions and pseudoarthrosis were classified into the nonunion group.
Statistical results of the meta-analysis concerning the fracture union rate after treatment for primary medial epicondyle fractures. The overall surgical group comprises all procedures involving open reduction and internal fixation, regardless of the specific technique applied. The authors classified both bony and fibrous unions into the union group, while nonunions and pseudoarthrosis were classified into the nonunion group.
LCI: lower confidence interval; HCI: higher confidence interval; Q: Cochran’s Q.
Range of motion
Full elbow ROM was restored in 78% (95% CI: 72%–84%) of surgically treated patients, compared with 73% (95% CI: 65%–80%) in those managed conservatively. Screw fixation demonstrated slightly better, though not clinically significant, outcomes (79%, 95% CI: 70%–86%) compared with K-wire fixation (78%, 95% CI: 61%–91%). Mild elbow ROM limitation (<10°) occurred in 20% (95% CI: 13%–28%) of surgical patients overall, with clinically relevant stiffness (≥10° limitation) observed in only 11% (95% CI: 6%–17%). Regarding forearm pronation–supination, full rotation was recovered in 85% (95% CI: 66%–98%) of surgical cases and 95% (95% CI: 89%–99%) of conservatively treated ones. Overall, these findings confirm that surgical management provides a high probability of full functional recovery, particularly when stable fixation is achieved. Detailed results are presented in Table 3.
Statistical results of the meta-analysis on the ROM achieved after treatment for primary medial epicondyle fractures. The overall surgical group comprises all procedures involving open reduction and internal fixation, regardless of the specific technique applied. Several authors also evaluated the ROR; therefore, separate analyses were performed. The term “full” elbow ROM referred to a clinically assessed complete flexion–extension movement at the elbow joint, whereas “full” ROR referred to a complete pronation–supination movement of the forearm.
ROM: range of motion; ROR: range of rotation; LCI: lower confidence interval; HCI: higher confidence interval; Q: Cochran’s Q.
Outcome measures
The mean Mayo Elbow Performance Score (MEPS) after surgery was 94 points (95% CI: 92–96), indicating good-to-excellent functional recovery, while conservative treatment achieved slightly higher scores (99 points, 95% CI: 98–100). Pain intensity, measured with the visual analog scale (VAS), was minimal in the surgical group (0 points, 95% CI: 0–1), suggesting effective restoration of elbow function without residual pain. Patient-reported disability was very low, with pooled Disabilities of the Arm, Shoulder, and Hand (DASH) and QuickDASH scores of 2 and 2 points, respectively. Collectively, these results emphasize that both surgical and conservative approaches can yield good to excellent elbow function when appropriately indicated. Detailed results are presented in Table 4.
Statistical results of the meta-analysis regarding the outcome measures, assessed with standardized scales, achieved after treatment for primary medial epicondyle fractures. The overall surgical group comprises all procedures involving open reduction and internal fixation, regardless of the specific technique applied. The VAS, designed to assess pain intensity, ranges from 0 (no pain) to 10 (worst imaginable pain), with higher scores indicating greater pain severity. The MEPS, used to evaluate elbow function including pain, motion, stability, and daily activities, ranges from 0 to 100 points, with higher scores indicating better elbow performance. The DASH questionnaire, used to evaluate upper extremity function and symptoms in daily activities, ranges from 0 (no disability) to 100 (maximum disability). The QuickDASH questionnaire, a shortened version of the DASH assessing upper limb disability and symptoms, ranges from 0 (no disability) to 100 (most severe disability).
LCI: lower confidence interval; HCI: higher confidence interval; Q: Cochran’s Q; VAS: visual analog scale; MEPS: Mayo Elbow Performance Score; DASH: Disabilities of the Arm, Shoulder, and Hand; QuickDASH: Quick Disabilities of the Arm, Shoulder, and Hand.
Some authors did not explicitly refer to the Valgus test by name, however, they assessed the clinical stability of the elbow while maintaining the same conceptual approach.
Complications
The overall complication rate following surgical treatment was 21% (95% CI: 16%–27%), compared to 36% (95% CI: 13%–63%) for conservative immobilization. A clinically relevant postoperative complication was ulnar nerve irritation symptoms, occurring in 9% (95% CI: 6%–12%) of all surgical cases, with a higher incidence after K-wire fixation (12%, 95% CI: 1%–32%) than with screws (7%, 95% CI: 3%–11%). Infection was relatively uncommon (5%, 95% CI: 3%–7%), particularly with screw fixation (3%, 95% CI: 1%–4%). Perceptible hardware prominence was reported in 34% (95% CI: 22%–47%) of screw cases. Heterotopic ossification and implant failure were rare (≤3%). Additionally, a reduction in muscle power was reported in 15% (95% CI: 8%–22%) of conservatively treated patients, underscoring the potential functional limitations of nonoperative management. Detailed results are presented in Table 5.
Statistical results of the meta-analysis on complications following treatment for primary medial epicondyle fractures. The overall surgical group comprises all procedures involving open reduction and internal fixation, regardless of the specific technique applied. The total complication rate was calculated only from studies in which the authors reported the overall number of complications in relation to the total number of treated patients.
LCI: lower confidence interval; HCI: higher confidence interval; Q: Cochran’s Q.
Discussion
This systematic review and meta-analysis synthesizes four decades of literature on the management of medial epicondylar fractures in pediatric and adolescent patients. Drawing from 65 studies and more than 2000 cases, it provides an overview of union rates, functional recovery, and complication profiles across various management strategies. The results highlight consistently high healing and functional outcomes following both surgical fixation and conservative treatment, with certain trends suggesting potential advantages of stable fixation techniques. Recent imaging-based work also suggests that medial epicondyle injuries may be more heterogeneous than previously assumed. Lee et al. described partial avulsion patterns involving the proximal ulnar collateral ligament (UCL) footprint and cortical sleeve avulsions, which represented 15.9% of medial epicondyle fractures in their cohort. This finding is clinically relevant because treatment decisions based only on displacement of the main epicondylar fragment may overlook displacement of the attached stabilizing soft-tissue structures. 74
The overall union rate for surgical management was 97%, with both screw fixation and K-wire fixation achieving a pooled union rate of 95%. In contrast, conservative treatment yielded a substantially lower union rate of 46%, with nonoverlapping confidence intervals between the overall surgical and conservative groups confirming the statistical significance of this difference. These findings indicate that internal fixation, irrespective of the implant used, is more reliably associated with bone consolidation than conservative management. Based on the obtained results, conservative treatment is associated with a high likelihood of nonunion, whereas surgical management appears clearly more appropriate for achieving stable bone union. However, the clinical relevance of nonunion depends on symptoms and later treatment requirements. Lee et al. reported that delayed surgery after failed initial nonoperative care or delayed diagnosis was feasible, particularly within 3 months of injury, but longer delays often required more complex procedures, including soft-tissue releases, UCL reconstruction, or ulnar nerve procedures. 75
Functional recovery, as measured by full elbow ROM, was also high in surgically managed patients (78%), with K-wires and screws demonstrating similar profiles (78% and 79%, respectively). Conservative treatment yielded comparable results (73%). Although the pooled incidence of ROM limitations ≥10° was higher in the surgical group than in the conservative treatment group (11% versus 6%), this difference was not statistically significant. Pronation–supination recovery was excellent across both treatment strategies, reaching 85% in surgical cases and 95% in conservatively treated cases. These data suggest that, with both approaches, maintaining a full or only minimally limited elbow ROM is highly probable. It is important to remember that limitations in joint mobility are not solely the result of improper bone union but rather reflect dysfunction of the entire joint complex, including the surrounding soft tissues and the duration of immobilization. This supports the importance of stable fixation constructs that allow early motion when surgery is selected. Haward et al. described a modified screw fixation technique augmented with a transosseous tension-band suture, in their early series of 13 elbows, all fractures united, functional ROM was achieved in all patients, and no cases of nonunion, symptomatic malunion, wire breakage, or stiffness requiring contracture release were observed. 76
Standardized outcome scores, such as the MEPS, generally indicated good-to-excellent functional results across treatment modalities. The mean MEPS was 94 in surgical cohorts and 99 in conservative cohorts. Although conservative cases appeared to score higher, this likely reflects case selection bias, with stable, low-energy injuries more frequently managed nonoperatively. Nevertheless, these differences are minimal and may be regarded as clinically irrelevant. VAS pain scores were uniformly low, and QuickDASH values remained low in both groups, reaching two in both surgical and conservative cohorts. No significant differences were observed between surgical and conservative treatment in terms of elbow stability assessed by the valgus stress test, with stable elbows reported in 97% of surgically treated patients and 91% of conservatively treated patients.
Importantly, the recent SCIENCE trial by Perry et al. provides high-quality randomized evidence that should be interpreted alongside the pooled observational data of the present meta-analysis. 70 In this multicenter trial, surgical fixation did not produce a clinically meaningful improvement in upper limb function, pain, return to activity, or quality of life compared with nonsurgical care at 12 months. Surgery was also associated with more additional procedures and higher treatment costs. From the UK NHS and Personal Social Services perspective, surgical fixation cost on average £2435 more per patient and had a 0% probability of being cost-effective at commonly accepted willingness-to-pay thresholds. These findings suggest that the higher radiographic union rate after surgery should not be interpreted alone, but rather balanced against patient-reported outcomes, complications, and health-care costs.
Complication rates represent a key aspect in assessing the risk associated with each type of therapy. Conservative care carried the highest overall complication rate at 36%, followed by ORIF using K-wires at 30% and screw-based fixation at 20%. Notably, ulnar nerve symptoms were more frequent after K-wire fixation (12%) than after screw fixation (7%), while infections were substantially more frequent with K-wires (15%) compared with screws (3%). Moreover, perceptible hardware prominence was common with screws, reaching 34%. Conservative treatment was also associated with a relatively high rate of reported muscle power loss (15%), possibly reflecting prolonged immobilization. In addition to postoperative complications, intraoperative technical events should also be considered. Arif et al. reported guidewire breakage in 6.1% of children treated with cannulated screw fixation, most often during guidewire repositioning or over-drilling. 77 Although retained intraosseous fragments were not associated with short-term infection, migration, or fixation failure, breakage significantly increased tourniquet time.
The presence of statistically distinct pooled estimates, particularly for union and complication rate, supports a more confident interpretation than previously possible. Screw fixation was consistently associated with high union rates, low complication incidence, and excellent functional recovery, making it a strong option when surgical intervention is indicated. However, functional outcomes and ROM were favorable across all treatment groups, suggesting that both surgical and conservative strategies can achieve excellent results when appropriately matched to patient and injury characteristics.
While our pooled dataset could not stratify outcomes by displacement magnitude, elbow stability, or ulnar nerve symptoms, many surgeons consider these features, particularly displacement >5 mm, valgus laxity, and level of activity, as practical indications for surgery.22,30 The observed trends in union and complication profiles reinforce this rationale. Conversely, conservative treatment appears well-suited to low-energy, minimally displaced fractures in clinically stable elbows, as reflected in high MEPS and good motion recovery.24,57 These findings emphasize the importance of careful patient selection and individualized decision-making in optimizing outcomes. The authors suggest that refraining from surgical treatment should be approached with caution, as the risk of nonunion is considerable.
This meta-analysis is not without its limitations. The results of any review are, by nature, constrained by the quality of data available in the literature. Some analyses could not be performed due to insufficient data availability. Future studies should provide a more detailed description of the indications on which the decision for surgical intervention was based, as well as report outcomes stratified according to these indications. It should be noted that the results are to some extent influenced by differences in patient selection between conservative and surgical treatment groups. Patients with big fragment avulsion type fractures are typically indicated for surgery, whereas those with small, nondisplaced fragments are more likely to receive conservative management. Randomized controlled trials would undoubtedly provide results free from this bias; however, randomization in this context appears difficult to achieve. From an ethical standpoint, assigning a patient without surgical indications to an operative group—or, conversely, managing a patient conservatively despite clear indications for surgery—would be inappropriate. Nevertheless, a more detailed breakdown of data in retrospective studies would certainly be beneficial for future research and the development of more refined conclusions. We believe that the results of our meta-analysis, despite these limitations, will be valuable in guiding clinical decision-making and will help estimate the risk of potential outcomes and complications in patients with medial epicondyle fractures.
Conclusion
This meta-analysis demonstrates that both surgical and conservative treatment of medial epicondylar fractures in pediatric and adolescent patients can result in excellent functional outcomes when appropriately indicated. Among surgical options, screw fixation was associated with high union rate and the lowest complication profile, with statistically distinct pooled estimates supporting its reliability in achieving stable healing and early mobilization. While conservative treatment was associated with lower union rates and higher complication rates, functional scores and motion recovery remained favorable. Nevertheless, the authors suggest that refraining from surgical treatment should be approached with caution, as the risk of nonunion is considerable. These findings support a tailored approach to management, where the choice of intervention should reflect fracture characteristics, patient activity level, and clinical stability. We believe that the pooled estimates from our study will be valuable in guiding clinical decision-making and will help assess the risk of potential outcomes and complications in patients with medial epicondyle fractures.
Supplemental Material
sj-docx-2-cho-10.1177_18632521261461017 – Supplemental material for Clinical outcomes of management of primary medial epicondylar fractures: A systematic review with meta-analysis
Supplemental material, sj-docx-2-cho-10.1177_18632521261461017 for Clinical outcomes of management of primary medial epicondylar fractures: A systematic review with meta-analysis by Michał Bonczar, Patryk Ostrowski, Jakub Wilk, Ignacy Jastrzębski, Jerzy Walocha, Mateusz Koziej and Mariusz Bonczar in Journal of Children's Orthopaedics
Supplemental Material
sj-docx-3-cho-10.1177_18632521261461017 – Supplemental material for Clinical outcomes of management of primary medial epicondylar fractures: A systematic review with meta-analysis
Supplemental material, sj-docx-3-cho-10.1177_18632521261461017 for Clinical outcomes of management of primary medial epicondylar fractures: A systematic review with meta-analysis by Michał Bonczar, Patryk Ostrowski, Jakub Wilk, Ignacy Jastrzębski, Jerzy Walocha, Mateusz Koziej and Mariusz Bonczar in Journal of Children's Orthopaedics
Supplemental Material
sj-docx-4-cho-10.1177_18632521261461017 – Supplemental material for Clinical outcomes of management of primary medial epicondylar fractures: A systematic review with meta-analysis
Supplemental material, sj-docx-4-cho-10.1177_18632521261461017 for Clinical outcomes of management of primary medial epicondylar fractures: A systematic review with meta-analysis by Michał Bonczar, Patryk Ostrowski, Jakub Wilk, Ignacy Jastrzębski, Jerzy Walocha, Mateusz Koziej and Mariusz Bonczar in Journal of Children's Orthopaedics
Supplemental Material
sj-pdf-1-cho-10.1177_18632521261461017 – Supplemental material for Clinical outcomes of management of primary medial epicondylar fractures: A systematic review with meta-analysis
Supplemental material, sj-pdf-1-cho-10.1177_18632521261461017 for Clinical outcomes of management of primary medial epicondylar fractures: A systematic review with meta-analysis by Michał Bonczar, Patryk Ostrowski, Jakub Wilk, Ignacy Jastrzębski, Jerzy Walocha, Mateusz Koziej and Mariusz Bonczar in Journal of Children's Orthopaedics
Footnotes
Acknowledgements
None.
Author contributions
M.i.B. – Methodology, Registration, Search, Extraction, Statistical analysis, Writing, Literature, Figures, Tables; P.O. – Writing; J.a.W. – Extraction, Figures; J.I. – Methodology, Search; J.e.W. – Writing; M.K. – Statistical analysis, Writing; M.a.B. – Writing.
Consent for publication
Not applicable.
Declaration of conflicting interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The authors received no financial support for the research, authorship, and/or publication of this article.
Ethics approval and consent to participate
This study is a systematic review and meta-analysis based exclusively on previously published data. Therefore, it did not involve any direct interaction with human participants, nor the collection of identifiable personal data. In accordance with current research guidelines, ethical approval from an institutional review board or ethics committee was not required for this type of study. Systematic reviews and meta-analyses that utilize data from publicly available sources are generally exempt from ethical approval, as no new data are collected from human subjects. As no human participants were directly involved in this study, written informed consent was also not required.
Availability of data and materials
The data presented in this study are available on request from the corresponding author.
Supplemental material
Supplemental material for this article is available online.
References
Supplementary Material
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