Authors: Mathilde Abildgaard, David Karimi, Kristine Rask Andreasen, Dennis Karimi, Tazio Maleitzke, Per Hölmich, Adam Witten
Categories: Review Article, Shoulder fracture, Proximal humerus fracture, Displacement, Fracture dislocation, Surgical indication, Treatment outcome
Source: JSES Reviews, Reports, and Techniques
Authors: Mathilde Abildgaard, David Karimi, Kristine Rask Andreasen, Dennis Karimi, Tazio Maleitzke, Per Hölmich, Adam Witten
There are no evidence-based guidelines to support the management of isolated greater tuberosity fractures. While the choice between nonoperative and operative treatment is generally based on the degree of fracture displacement, the definition of an acceptable displacement continues to be debated. Consequently, the ideal management of these fractures can be a therapeutic challenge. The objective of this study was to create an overview of the literature investigating the treatment of isolated greater tuberosity fractures.
A scoping review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension guidelines for scoping reviews (PRISMA-ScR). Electronic databases MEDLINE, EMBASE, SPORTDiscus, and CINAHL were systematically searched from inception to September 29, 2024. Original studies investigating the treatment of isolated greater tuberosity fractures were eligible for inclusion. Screening of studies was independently performed by 3 reviewers. Data items were extracted using a standardized charting form. Risk of bias of the included studies was assessed by 2 independent reviewers using the Newcastle-Ottawa Quality Assessment Scale.
3.788 records were identified in the search, 296 were retrieved for full-text screening, of which 59 were included. No randomized controlled trials were identified. 88% of the included studies were retrospective and 98% had a moderate or high risk of bias. Most of the included studies investigated operative treatment of displaced fractures (defined as >5 mm) in patient populations with a mean age between 40 and 60 years. Few studies investigated nonoperative treatment and treatment in young (<40 years) or elderly (>60 years) patients. Detailed fracture characteristics were not consistently reported. Accordingly, the size of the fragment was reported in 8% of the included studies, fractures were subclassified into avulsion, split or depression type in 29% of the included studies, and the direction of fragment displacement was reported in 34% of the included studies.
The literature regarding the treatment of isolated greater tuberosity fractures is comprised of studies with a moderate to high risk of bias and a lack of randomized controlled trials. A 5 mm fracture displacement threshold is often used to guide treatment, though it has not been validated in clinical studies. High-quality studies are needed to establish evidence-based guidelines and improve clinical decision-making.
Isolated fractures of the greater tuberosity account for up to 14%-20% of all proximal humerus fractures,^5^^,^^57^ and are associated with both low-energy trauma in elderly patients and high-energy trauma in younger patients.^68^ The management of isolated greater tuberosity fractures involves numerous treatment options that can be classified as either nonoperative or operative. While nondisplaced fractures are often managed nonoperatively, displaced fractures are generally believed to require surgery to prevent nonunion and malunion, altered rotator cuff biomechanics, and subacromial impingement.^8^^,^^59^ While the choice between nonoperative and operative treatment is generally based on the degree of fracture displacement, the amount of acceptable displacement continues to be a subject of debate. In 1970, Neer published his classification system for proximal humerus fractures and suggested a fracture displacement >10 mm as the threshold for operative treatment.^44^ With the ongoing evolution of surgical techniques and a better understanding of the function and biomechanics of the rotator cuff, Neer's recommendation can be questioned. Furthermore, the treatment strategy for isolated greater tuberosity fractures likely depends on a variety of factors in addition to the degree of fracture displacement, including patient age and activity level, and fracture characteristics such as fragment size, morphology, and direction of displacement. Currently, there are no evidence-based guidelines to support clinical decision-making. Creating an overview of the literature may help guide treatment and research of isolated greater tuberosity fractures, particularly in relation to different degrees of displacement and age groups.
To create an overview of the literature investigating the treatment of isolated greater tuberosity fractures.
A scoping review approach was chosen to create an overview of the literature regarding the treatment of isolated greater tuberosity fractures. This scoping review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension guidelines for scoping reviews (PRISMA-ScR),^63^ and was registered with Open Science Framework.^25^
This scoping review included original studies investigating the clinical outcomes of isolated greater tuberosity fractures. The following study types were eligible for randomized controlled trials, prospective cohort studies, retrospective cohort studies, case-control studies and case series. Protocol articles, review articles, biomechanical studies, secondary analyses from previous studies and case series with fewer than 10 participants were excluded, as well as studies presented in languages other than English, Danish, German, Norwegian, or Swedish.
A search strategy was developed in consultation with a biomedical librarian. Using a combination of keywords and medical subject heading terms related to greater tuberosity fractures, the following electronic databases were systematically searched from inception to September 29, MEDLINE (via PubMed), EMBASE, SPORTDiscus, and CINAHL. The search strategy and terminology were adapted to the respective databases (Supplementary Appendix Table S1).
Identified records were compiled into Mendeley Reference Manager (V.2.122.0; Elsevier, Amsterdam, Netherlands) where duplicates were identified and removed by 1 reviewer. Three reviewers, screening in pairs, independently screened the records using the Covidence systematic review software (Veritas Health Innovation, Melbourne, Australia). Discrepancies among reviewers were resolved by dialog. Exclusion of studies was based on the following hierarchical language, study type, population, and secondary analysis. One reviewer conducted the data extraction from the included studies.
A data charting form was developed and tested in an iterative process before the final data extraction was performed. Data items were extracted using a standardized charting form and systematically charted within well-defined categories. Categorical data were presented as counts with percentages, and continuous data were presented as means with standard deviations or ranges.
The following data items were general study information (title, author(s), year of publication, study design, and sample size), and patient demographics (gender and age; <40 years, 40-60 years, >60 years). Both the number of patients included in the study and the number of patients available at the final follow-up were extracted.
Data items regarding fracture characteristics and treatment strategy were systematically charted within the following degree of fracture displacement (<3 mm, <5 mm, >5 mm, and >10 mm), fracture type (isolated or comminuted), type of treatment (nonoperative or operative treatment), and surgical approach (open, mini-open or arthroscopic). The specific surgical approach was extracted as literally as possible, as well as charted within the categories. Open treatment was defined as open reduction and internal fixation using a deltopectoral approach, and mini-open treatment was defined as the same using a deltoid-split approach. The reporting of other fracture characteristics such as fragment size, fracture morphology (avulsion, split, or depression fracture), direction of displacement, classification system, associated injuries such as rotator cuff tears, and treatment-related complications were extracted as well. Mean follow-up and mean patient-reported outcome measures (PROMs) at the final follow-up were extracted as continuous data. Studies with unclear reporting or missing data items within a given category were excluded from the corresponding analyses.
The methodological quality and risk of bias of the included studies were assessed using the Newcastle-Ottawa Quality Assessment Scale (NOS).^67^ NOS consists of 8 items in 3 (i) selection, (ii) comparability, and (iii) outcome, with a maximum score of 9 points. A higher score indicates a lower risk of bias. A score of 0-3 was considered to have a high risk of bias, a score of 4-6 was considered to have a moderate risk of bias, and a score of 7-9 was considered to have a low risk of bias.
When using the NOS scale authors are required to select an adequate follow-up period for outcome of interest, as well as an adequate percentage of loss to follow-up. A study was given 1 point in the outcome category's second item ‘Was follow-up long enough for outcomes to occur’ if follow-up was more than 1 year. Furthermore, a study was given 1 point in the outcome category's third item ‘Adequacy of follow-up of cohorts’ if loss to follow-up was less than 5%. If a study did not define a primary outcome measure and used several outcome measures, including PROMs, the outcome category (i) assessment of outcome was rated based on the use of PROMs. The quality assessment was conducted by 2 independent reviewers (orthopedic surgery residents) familiarized with the NOS according to the standard scoring system. Discrepancies among reviewers were resolved by dialog.
3.788 records were identified in the electronic databases, 296 were retrieved for full-text screening, and 59 were included in this study (Fig. 1). The reviewers had an agreement of 91% for the full-text screening. Disagreements among reviewers were resolved by dialog.Figure 1Flow chart of identification, screening, and inclusion process.
The included studies were published between 1991 and 2024. No randomized controlled trials were included (Table I). Fifty-two (88%) studies were retrospective cohort studies. Of the included studies, 54 (92%) investigated the treatment of isolated greater tuberosity fractures, while 5 (8%) studies investigated the treatment of proximal humerus fractures and included a subgroup analysis of isolated greater tuberosity fractures. Ten (17%) studies investigated isolated greater tuberosity fractures associated with shoulder dislocation, 3 (5%) studies investigated associated rotator cuff tears, and 3 (5%) studies investigated missed or occult isolated greater tuberosity fractures. The mean sample size of the studies ranged from 10 to 199 patients (mean 49 patients). The age of the participants ranged from 17 to 93 years, with a weighted mean age of 54 years (confidence intervals were not calculated, as standard deviations were not consistently reported across the included studies). Most of the studies reported a mean age between 40 and 60 years (77%).Table ICharacteristics of included studies.No. of studies (%) n = 59Study type Randomized controlled study0 (0) Prospective study7 (12) Retrospective study52 (88)Degree of fracture displacement <5 mm11 (19) >5 mm28 (47) Both <5 mm and >5 mm9 (15) Not reported11 (19)Type of treatment Operative41 (70) Nonoperative12 (20) Both operative and nonoperative6 (10)Surgical approach Open14 (24) Mini-open26 (44) Arthroscopic18 (30)Mean age in population <40 yr4 (7) 40-60 yr45 (77) >60 yr10 (16)
The fracture displacement was mapped using the same categories provided by the studies. Twenty-eight (47%) of the included studies investigated the clinical outcomes of displaced fractures, of which 21 (36%) studies used >5 mm as fracture displacement threshold, and 7 (12%) studies used >10 mm as fracture displacement threshold. Eleven (19%) studies investigated the clinical outcomes of nondisplaced or minimally displaced fractures, of which 6 (10%) studies used <5 mm as fracture displacement threshold, and 5 (8%) studies used <3 mm as fracture displacement threshold. Nine (15%) studies investigated the clinical outcomes of both displaced and nondisplaced or minimally displaced fractures. Eleven (19%) studies did not quantitatively report the degree of fracture displacement but instead used the terms “nondisplaced” or “displaced”.
Across all included studies, 3 different fracture classification systems were used. Fourteen (24%) studies used the Neer classification system,^44^ 12 (20%) used the Arbeitsgemeinschaft für Osteosynthesefragen classification system,^3^ and 11 (19%) used the Mutch classification for greater tuberosity fracture morphology.^43^ Twenty-six (44%) studies did not report using a fracture classification system. Specific fracture characteristics such as fracture morphology (avulsion, split, or depression fracture), fragment size, direction of displacement, and degree of fragment comminution were not consistently reported in the included studies. Accordingly, fractures were subclassified into avulsion, split or depression fractures in 17 (29%) studies, of which 3 studies included only avulsion type fractures, and 2 studies included only split type fractures. The size of the greater tuberosity fragment was reported in 5 (8%) studies, and the degree of fragment comminution was reported in 28 (47%) studies. Furthermore, the direction of fragment displacement was assessed in 20 (34%) studies.
Forty-one (70%) of the included studies investigated the clinical outcomes of operative treatment, while 12 (20%) studies investigated the clinical outcomes of nonoperative treatment. Six (10%) studies investigated and compared the clinical outcomes of both operative and nonoperative treatment. Taking both the degree of fracture displacement and treatment strategy into account, 32 (54%) studies investigated operative treatment of displaced fractures (>5 mm), while 6 (10%) studies investigated operative treatment of nondisplaced or minimally displaced fractures (<5 mm). Thirteen (22%) studies investigated nonoperative treatment of nondisplaced or minimally displaced fractures (<5 mm), and 7 (12%) studies investigated nonoperative treatment of displaced fractures (>5 mm).
Of the studies investigating operative treatment, 26 (44%) reported using a mini-open surgical approach, 18 (30%) reported using an arthroscopic surgical approach, and 14 (23%) reported using an open surgical approach. Thirteen (22%) studies included a population where different types of surgical approaches were used. Across all studies, several different surgical techniques were used. Suture anchor fixation (arthroscopic (25%) or mini-open (20%)) and open reduction with plate fixation (18%) were the most frequent (Fig. 2).Figure 2Treatment modalities between 1991 and 2024.
The mean follow-up ranged from 1 month to 6.3 years, with a weighted mean follow-up of 2.5 years. Treatment outcomes were evaluated with PROMs in all studies, and with radiographic follow-up in 53 (90%) studies. Across all studies, clinical outcomes were evaluated using 22 different PROMs, with 34 (58%) studies using ≥2 PROMs. The Constant-Murley score (CS)^14^ was used in 34 (58%) studies, the American Shoulder and Elbow Surgeons (ASES) score^55^ was used in 20 (34%) studies, and The University of California-Los Angeles shoulder scale^2^ was used in 13 (22%) studies. Shoulder range of motion was assessed at the final follow-up in 35 (59%) studies, and patient-reported shoulder pain was assessed using the Visual Analog Scale in 25 (42%) studies. Associated injuries such as rotator cuff tears were reported in 31 (53%) studies and treatment-related complications were reported in 52 (88%) studies. Accordingly, the occurrence of nonunions and malunions was reported in 5 studies investigating nonoperative treatment (8% of the included studies) and in 7 studies investigating operative treatment (12% of the included studies).
An overview of mean PROMs at the final follow-up is shown in Figure 3. Among the studies investigating operative treatment, patients reported a mean CS of 88 at the final follow-up. Among the studies investigating nonoperative treatment, patients with nondisplaced fractures reported a mean CS of 79 at the final follow-up, and patients with displaced fractures reported a mean CS of 73 at the final follow-up. Studies with unclear reporting or missing data items (n = 11, 19%) were excluded from the overview, as well as studies that used PROMs not comparable to CS or ASES (n = 10, 17%).Figure 3Mean scores of patient-reported outcome measures at the final follow-up. Rhomb: mean patient-reported outcome measures (PROMs), standard deviation, colored dashed line: mean patient-reported outcome measures within the 4 categories. CS, Constant Murley score; ASES, American Shoulder and Elbow Surgeons. Both scores range from 0 to 100, where 0 indicates the worst possible shoulder function and 100 indicates the best possible shoulder function. ★ Fracture displacement threshold defined as 3 mm. ★★ Fracture displacement threshold defined as 10 mm.^1^^,^^4^^,^^6^^,^^9^^,^^10^^,^^15^^,^^23^^,^26, 27, 28^,^30, 31, 32, 33, 34^,^^36^^,^^40^^,^^42^^,^48, 49, 50, 51^,^^53^^,^^54^^,^^60^^,^^61^^,^64, 65, 66^,^69, 70, 71, 72, 73
The majority of the included studies investigated the clinical outcomes of isolated greater tuberosity fractures in a patient population with a mean age between 40 and 60 years. Accordingly, 4 (7%) studies reported a mean age below 40 years, 45 (77%) reported a mean age between 40 and 60 years, and 10 (16%) reported a mean age above 60 years. Four (7%) studies investigated operative treatment in a patient population with a mean age below 40 years, and 7 (12%) studies investigated operative treatment in a patient population with a mean age above 60 years. One study investigated operative treatment exclusively in an elderly patient population by including only patients with age above 60 years.^10^ Only 1 study investigated nonoperative treatment in a patient population with a mean age below 40 years,^12^ and 3 (5%) studies investigated nonoperative treatment in a patient population with a mean age above 60 years.^19^^,^^24^^,^^58^
All of the included studies reported a mean age of the patient population, but only 1 study stratified the treatment strategy based on age, and used different fracture displacement thresholds for different age groups, with a lower threshold for younger patients (<65 years, >3 mm) than older patients (>65 years, >5 mm).^17^
The NOS was used to assess the risk of bias in the included studies. The total score of the included studies ranged from 3 to 7 points out of a maximum of 9 points. Fifteen (25%) studies had a high risk of bias, 43 (73%) studies had a moderate risk of bias, while only 1 (2%) study had a low risk of bias (Table II). It is worth noting that 58 studies (98%) did not include a control group that could serve as a reference for comparing outcomes following the investigated treatment ((ii) selection of the non-exposed cohort).Table IIQuality assessment according to the Newcastle-Ottawa scale (NOS).Author (yr)SelectionComparabilityOutcomeOverall qualityRepresentativeness of the exposed cohortSelection of the non-exposed cohortAscertainment of exposureOutcome of interest was not present at startComparability of cohorts on the basis of the design or analysisAssessment of outcomeFollow-up period∗Adequacy of follow-up†Rakowski (2022)^52^•••••••7/9Hebert-Davies (2015),^24^ Liao (2016),^36^ Lu (2013),^38^ Pan (2021),^46^ Platzer, (2005),^50^ Sun (2020),^61^ Tao (2024),^62^ Wang (2023),^65^ Yin (2012)^70^••••••6/9Foruria (2010),^19^ Makaram (2023)^39^••••••6/9Bahman (2021),^4^ Razaeian (2020),^54^ Wang (2012)^66^•••••5/9Kim (2023),^31^ Rouleau (2016)^56^•••••5/9Ganokroj (2022)^21^•••••5/9Dussing (2018)^17^••••4/9Zeng (2021)^72^••••4/9Furuhata (2022)^20^••••4/9Amroodi (2016),^1^ Bhatia (2006),^59^ Chen (2013),^9^ Cirigliano (2024),^13^ Choi (2018),^11^ Gillespie (2015),^22^ Gumina (2008),^23^ Hu (2018),^26^ Jang (2018),^27^ Ji (2010),^30^ Kokkalis (2018),^32^, Kong (2022),^33^ Li (2017),^35^ Lin (2020),^37^ Longo (2018),^37^ Rath (2013),^53^ Park (2013),^49^ Park (2015),^48^ Platzer (2008),^51^ Verdano (2014),^64^ Ryan (2022),^58^ Xue (2018),^69^ Yoon (2017)^17^••••4/9Catelas (2023),^45^ Cheng (2019),^10^ Dimakopoulos (2007),^15^^,^^16^ Dimakopoulos (2007),^16^ Chun (1994),^12^ Flatow (1991),^18^ Ji (2016),^29^ Lee (2021),^34^ Mattyasovszky (2011),^40^ Miquel (2021),^41^ Mouraria (2023),^42^ Zhang (2020)^73^•••3/9Jellad (2011),^28^ Bogdan (2017),^7^ Schöffl (2010)^60^•••3/9∗Adequate follow-up period for outcome of interest was defined as more than one year.†Adequate follow-up of patients was defined as loss to follow-up less than 5%.
This scoping review shows that the literature investigating the treatment of isolated greater tuberosity fractures is comprised of studies with a moderate to high risk of bias. Accordingly, most of the included studies were retrospective, and notably, no randomized controlled trials were included. This represents a significant methodological limitation of the literature. The scarcity of randomized studies may partly result from real-world constraints, including concerns raised by both patients and surgeons that random allocation of treatment could potentially increase the risk of complications or impact patient outcomes negatively. This concern could lead to reluctance in enrolling patients in randomized trials. It may also result from heterogeneity in fracture morphology, patient demographics, and treatment thresholds, which complicates the development of standardized inclusion criteria across patient populations. Whereas retrospective studies can be valuable in the development of clinical guidelines, their inherent susceptibility to bias limits the underlying evidentiary strength.
While there are no evidence-based guidelines to support the management of isolated greater tuberosity fractures, this review shows that the choice between nonoperative and operative treatment is generally based on the degree of fracture displacement. Accordingly, all the included studies stratified treatment based on fracture displacement, with the majority of studies using a 5 mm threshold. Despite this common practice, this review found no high-quality studies supporting the use of a 5 mm threshold for treatment stratification. Instead, the 5 mm threshold is based on findings from biomechanical studies^8^^,^^47^ and retrospective cohort studies, which carries an inherent risk of selection bias. Considering that the widely accepted 5 mm threshold does not seem to have any clinical validation beyond nonrandomized studies, the clinical applicability of the threshold should be questioned.
While the degree of fracture displacement could correlate with treatment outcomes following nonoperative and operative treatment, several patient-related factors and additional fracture characteristics may play a role as well. However, there was a considerable heterogeneity across the included studies in the reporting of such factors. Fragment size, fracture morphology (avulsion, split or depression fracture), and direction of fracture displacement were most often not reported or given consideration in the included studies. This, perhaps, represents an effort to standardize a simple approach to treatment by focusing primarily on fracture displacement as the determining factor. It could also represent a significant gap in the understanding of the complexity of isolated greater tuberosity fractures, as these factors not only influence the choice of treatment and fixation strategies, but also reflect the risk of various associated injuries, such as rotator cuff tears, glenoid fractures, and glenohumeral dislocations.^57^
In recent years, the direction of fracture displacement has become increasingly recognized in research as an important factor to consider in the treatment of isolated greater tuberosity fractures,^58^^,^^64^ still only 34% of the included studies reported the direction of fracture displacement. The recommendations regarding the 5 mm threshold made by Park et al in a mostly biomechanical study were partially based on the assumption that nonoperative treatment of displaced fractures could result in altered rotator cuff biomechanics and subacromial impingement due to superior displacement of the fragment.^47^ Thus, fractures displaced superiorly may have a greater impact on rotator cuff biomechanics and subacromial impingement compared to fractures with inferior displacement. Verdano et al found that nonoperative treatment of fractures with posterosuperior displacement led to significantly poorer clinical outcomes compared to fractures displaced in other directions,^64^ indicating that the direction of fracture displacement may be an important factor to consider.
Patient age and activity level are other important factors to consider. All the included studies reported a mean age of the patient population, with the majority of studies investigating the treatment of isolated greater tuberosity fractures in a patient population with a mean age between 40 and 60 years. However, only a few of the included studies reported the treatment outcomes of young and elderly patients or stratified treatment based on age. While the predominance of middle-aged patients reflects the epidemiology of the injury, the lack of evidence for younger and older patients limits the generalizability of the findings. The inconsistency in the reporting of factors such as direction of fracture displacement and patient age could have significant implications for the interpretation of the findings, as a ‘one-size-fits-all’ approach to treatment may lead to suboptimal treatment outcomes for individual patients.
Another interesting finding of this review was the scarcity of studies investigating nonoperative treatment. This represents a critical gap in the literature. Among the studies investigating nonoperative treatment, the reported clinical outcomes varied significantly both within and across studies (Fig. 3 and Supplementary Appendix Table S2). Some studies found no significant difference in clinical outcomes of patients treated nonoperatively regardless of the fracture displacement, questioning the current 5 mm threshold often used as indication for operative treatment.^54^^,^^58^ Other studies reported suboptimal clinical outcomes of patients treated nonoperatively, and highlighted the risk of secondary displacement, thus advocating for operative treatment.^51^ Owing to the number of studies investigating nonoperative treatment and the retrospective nature of the literature, the comparability of the findings is limited.
Furthermore, this review only identified 6 studies comparing nonoperative and operative treatment of isolated greater tuberosity fractures, and their results were contradictory. Platzer et al found that operative treatment of fractures with >5 mm displacement resulted in significantly better clinical outcomes compared to nonoperative treatment.^51^ However, the nonoperatively managed group included only 11 patients, of which 9 patients were available for the final follow-up, and the authors explicitly stated that the patients were managed nonoperatively due to comorbidities, advanced age, and lack of compliance, thus introducing a considerable risk of selection bias. Conversely, Mattyasovszky et al found no difference in clinical outcomes when comparing operative and nonoperative treatment in the “6-10 mm displacement” group.^40^ Owing to the scarcity of comparative studies and the contradictory nature of the findings, the evidence cannot be considered sufficient to support clinical guidelines. The variation in results from comparing nonoperative and operative treatment could possibly be attributed not only to the inconsistent use of displacement thresholds, but also to the diverse surgical approaches reported in the included studies. Accordingly, the surgical approaches and surgical techniques varied considerably across studies and time (Fig. 2), which further hinders the comparability of the findings.
When evidence is summarized across the included studies (Fig. 3), patients treated operatively generally reported higher PROMs at the final follow-up compared to patients treated nonoperatively. Among the studies investigating operative treatment, patients reported a mean CS of 88 at the final follow-up. Among the studies investigating nonoperative treatment, patients with nondisplaced fractures seemed to have better clinical outcomes (mean CS = 79) than those with displaced fractures (mean CS = 73). This indicates that operative treatment of isolated greater tuberosity fractures may result in better clinical outcomes than nonoperative treatment, and that the degree of fracture displacement could be associated with the treatment outcome. However, there are several important limitations to such an interpretation. First, due to the scarcity of studies comparing nonoperative and operative treatment, and the general methodological heterogeneity of the included studies, a meta-analysis was not performed. Second, it must be considered that a large variation in PROMs (large standard deviation) was observed among the included studies, and that there was a general large overlap of PROMs across the different treatment groups. Third, a large variation in surgical approaches and surgical techniques was seen across the included studies (Fig. 2). This further compromises the comparability of studies investigating operative treatment and limits the generalizability of the findings.
In summary, there is a lack of high-quality studies concerning the treatment of isolated greater tuberosity fractures. This represents a significant methodological limitation of the literature, which hinders the development of evidence-based guidelines to support clinical decision-making. While the 5 mm threshold provides a convenient guideline for the management of isolated greater tuberosity fractures, its clinical application should likely be contextualized within a broader multifactorial approach to treatment. The choice between nonoperative and operative treatment often seems to be based on the degree of fracture displacement, while other factors such as patient-related factors and fracture characteristics were often not reported or given consideration in the included studies. This highlights significant knowledge gaps in the management of isolated greater tuberosity fractures. There is a need for randomized controlled trials comparing nonoperative treatment to operative treatment in well-defined patient populations. Though no randomized studies were identified, the existing evidence remains valuable in guiding the methodological approach of future randomized controlled trials. Future studies should preferably apply a multifactorial approach to treatment, accounting for relevant patient-related factors and fracture characteristics, as these may affect treatment outcome. Additionally, future studies should aim to apply a systematic methodological approach to ensure reproducibility of the findings.
This scoping review provides a comprehensive overview of the literature investigating the treatment of isolated greater tuberosity fractures. The broad inclusion criteria were chosen to gain a broad perspective of the current literature with as little selection bias as possible. While this approach provides a more comprehensive overview of the literature, it also increases the heterogeneity of the included studies and reduces their comparability. Therefore, more detailed analyses of the included studies were not possible without the risk of considerable biases. Furthermore, due to the lack of comparative studies, pooled analyses of treatment outcomes were not possible. This should be considered a limitation. The systematic search methodology, the independent screening of articles, and the quality assessment of the included studies are strengths that improves the transparency and reproducibility of the present study.
The literature regarding the treatment of isolated greater tuberosity fractures is comprised of studies with a moderate to high risk of bias and a lack of randomized controlled trials. A 5 mm fracture displacement threshold is often used to guide treatment, though it has not been validated in clinical studies. High-quality studies are needed to establish evidence-based guidelines and improve clinical decision-making.
Funding: No funding was disclosed by the authors.
Conflicts of The authors, their immediate families, and any research foundation with which they are affiliated have not received any financial payments or other benefits from any commercial entity related to the subject of this article.