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Shoulder Arthroplasty for Acute Proximal Humerus Fracture

Overview

Arthroplasty for acute proximal humeral fractures offers satisfactory long-term pain relief, though overall shoulder motion remains less predictable [1]. While elderly patients requiring admission are frail with elevated mortality risks [4], those undergoing acute reverse total shoulder arthroplasty (rTSA) demonstrate superior 5-year functional outcomes compared to hemiarthroplasty [6] and better results than initial nonoperative management, which carries higher complication rates [5]. Available literature suggests rTSA for complex fractures yields more favorable clinical outcomes than hemiarthroplasty [26], with anatomic tuberosity healing further improving objective and subjective results in the elderly [2].

However, enthusiasm for rTSA in patients 65 years and older must be moderated by increased in-hospital risks for major adverse events and surgical complications [21]. RTSA performed for acute 3- and 4-part fractures yields overall worse clinical outcomes and active range of motion compared to RTSA performed for elective indications [66]. No clear benefits were observed in treating patients 65 years or older with four-part fractures using either hemiarthroplasty or nonoperative treatment [67], though a new intramedullary support nail and plate system has shown advantages for 3- or 4-part fractures in older patients at 1-year follow-up [3]. The largest long-term follow-up of acute proximal humeral fractures treated with hemiarthroplasty remains a key reference point [9], and most studies indicate that only 1 or 2 lost patients would alter conclusions for dichotomous outcomes [16].

Anatomy & Pathophysiology

Osseous and Articular Mechanics

Systematic repair of the tuberosities around the implant improves shoulder rotational ability, provided their consolidation is anatomic [8]. While greater tuberosity healing does not appear to impact reverse shoulder arthroplasty biomechanics during abduction or forward flexion, it significantly affects biomechanics during external rotation [28]. Varus and antecurvatum proximal humerus deformities as small as 15 degrees are associated with statistically significant alterations in glenohumeral joint mechanics [40]. During hemiarthroplasty for four-part proximal humeral fractures, glenohumeral joint forces are significantly displaced superiorly with minimal and moderate amounts of glenohumeral abduction [30]. The control volume represents an important anatomic and functional area of the proximal humerus [44].

Neurovascular and Surgical Approach

Vertical abduction has the greatest effect on axillary nerve position during the split lateral deltoid approach, whereas horizontal glenohumeral forward flexion and humeral rotation have little effect [43].

Radiographic Assessment and Functional Metrics

Variability in the glenopolar angle is revealed with increased AP rotational offset of the shoulder radiograph, demonstrating inaccuracies even at institutions with established protocols [38]. Objective strength measurement is recommended at the insertion of the deltoid muscle in a 90° abduction position within the scapula plane [35]. Range of motion and strength thresholds can identify subjects with normal shoulder function [29]. Dominance of the affected shoulder has no influence on functional and quality of life outcomes compared with the nondominant shoulder [37].

Classification

Neer: The Neer classification system covers 98% of all proximal humeral fractures and is appropriate for clinical practice [58]. However, classifications based on CT scans and plain radiographs using this system are not very reliable or reproducible due to difficulty in determining which segments are fractured [60].

HGLS: The HGLS classification is a reliable method of describing fractures of the proximal humerus compared with the Neer and AO systems [56].

Standardized CT Protocol: A new classification system with emphasis on the qualitative aspects of proximal humeral fractures showed high reliability when based on a standardized imaging protocol including computed tomography scans [49].

Other Considerations: Consensus when managing proximal humerus fractures is limited to specific scenarios, whereas lack of consensus still exists in others [11].

Clinical Presentation

Proximal humeral fractures follow characteristic patterns [7], with the majority of cases in elderly patients managed nonoperatively [10, 23]. However, patients presenting with traumatic shoulder injuries and normal radiographs may harbor occult greater tuberosity fractures, identifiable via the highly sensitive and specific anterior bruise sign (ABS) [22]. While most pediatric patients experience favorable results with infrequent complications [50], elderly patients sustaining these fractures face a significantly higher risk of mortality up to one year post-injury compared with the general population [25]. Mortality rates for fragility fractures are universally high regardless of specific risk factors [15], and elderly patients requiring admission are often frail with a greater-than-average mortality risk for their age [4].

Clinical evaluation must account for the fact that nonoperative treatment yields considerable variation in shoulder-specific and general health outcomes at one year, with a substantial proportion of patients reporting poor perceived functional outcomes [13]. Conversely, patients undergoing initial nonoperative management demonstrate worse functional outcomes and higher complication rates than those receiving acute reverse total shoulder arthroplasty [5]. Consensus on management remains limited to specific scenarios, while significant heterogeneity exists in the terminology and definitions used to describe complications following non-surgical care [11, 12].

Acute Injury vs. Surgical Considerations

In elderly patients, the application of intramedullary support nail and plate systems to 3- or 4-part fractures confirms an advantage at 1-year follow-up [3]. For patients undergoing arthroplasty, satisfactory long-term pain relief is achievable, though overall shoulder motion results remain less predictable [1]. Anatomic tuberosity healing in elderly patients undergoing reverse shoulder arthroplasty significantly improves both objective and subjective outcomes [2]. Factors associated with poor results after internal fixation of three-part and four-part fracture-dislocations include being a woman, the presence of a four-part fracture dislocation, and the absence of metaphyseal head extension [57]. Prevention of local complications, particularly those leading to severe varus deviation, appears essential to improve shoulder function [55].

Comorbidities and Readmissions

Patient medical comorbidities must be considered before and during postoperative care, as the majority of unplanned hospital readmissions are associated with medical diagnoses rather than surgical complications [19]. While reverse shoulder arthroplasty serves as a powerful tool for managing fracture sequelae when joint-preserving options are suboptimal, success requires careful management of the tuberosities and an understanding of associated pearls and pitfalls [54]. A wide range of outcome measures are utilized in proximal humeral fracture studies, yet there is limited evidence regarding their psychometric properties within this specific population [59].

Investigations

Plain radiography: Fractures of the proximal humerus follow characteristic patterns [7], though elderly patients requiring admission are frail and subject to a greater-than-average risk of mortality for their age [4]. A majority of patients with proximal humeral fractures undergo non-operative treatment [10]. The anterior bruise sign (ABS) is a highly sensitive and specific clinical aid to identify patients with an occult greater tuberosity fracture in those presenting with a traumatic shoulder injury and normal radiographs [22]. Convolutional neural networks (CNNs) proficiently rule out proximal humerus fractures on plain radiographs [76]. However, missed posterior dislocation of the shoulder after intramedullary fixation is an extremely rare injury that can be missed due to inadequate initial and postoperative x-ray images and incorrect interpretation [79].

CT: There is relevant variability in displacement measurements between shoulder radiographs and CT scans in the coronal plane [73]. Nearly 30% of cases suggesting surgical treatment on radiographs are reclassified for conservative treatment based on CT findings [73]. The inherent nature of medial comminution of proximal humeral fracture may lead to inferior radiographic outcomes [71].

MRI: Patients with persistent post-traumatic shoulder pain and limitation of function warrant MRI investigation to identify occult greater tuberosity fractures [72]. Undisplaced greater tuberosity fractures can be managed non-operatively with good results [72].

Other Considerations: Despite a delayed diagnosis of more than one year, osteotomy and realignment of a displaced lesser tuberosity fracture can be successful and enhance overall shoulder function [17]. The routine use of 3D-printed models may not be beneficial for classifying proximal humeral fracture patterns beyond the information gained from currently available imaging modalities [74]. The use of 3D-printed models as the sole determinant for recommending surgical intervention should be avoided at this time [74]. Consensus when managing proximal humerus fractures is limited to specific scenarios, whereas lack of consensus still exists in others [11].

Treatment

Non-Operative

A majority of patients with proximal humeral fractures undergo non-operative treatment, which demonstrates successful outcomes and union rates greater than 90% [10, 51]. Most proximal humeral fractures in elderly patients can be treated nonoperatively with good functional outcomes [23]. Short and long periods of immobilization yield similar results for nonoperatively treated proximal humeral fractures, independent of the fracture pattern [20]. However, nonoperative treatment produces considerable variation in shoulder-specific and general health outcomes at 1 year, with a substantial proportion of patients having poor perceived functional outcomes [13]. Significant heterogeneity exists in the terminology and definitions used to describe complications following non-surgical management of proximal humeral fractures [12]. Nonsurgical management of proximal humerus fractures decreased during the study period [46].

Operative

Indications: Patients who undergo initial nonoperative management have worse functional outcomes and higher complication rates than those who undergo acute reverse total shoulder arthroplasty (rTSA) for proximal humeral fractures [5]. Treatment with reverse shoulder arthroplasty provides superior functional outcomes compared with conservative treatment for patients presenting with an acute proximal humeral fracture [47]. There is no significant difference in clinical outcomes at 2 years between surgery and non-operative treatment in patients 60 years of age or older with displaced 2-part fractures of the proximal humerus [48]. Nonsurgical treatment should have a more prominent role in the treatment of proximal humeral fractures compared to locking plate fixation [52]. Elderly patients requiring admission after sustaining a proximal humeral fracture are frail and subject to a greater-than-average risk of mortality for their age [4].

Surgical Approach / Technique: Shoulder rotational ability is improved by systematically repairing the tuberosities around the implant in complex shoulder fractures treated by reverse shoulder arthroplasty, provided their consolidation is anatomic [8]. In elderly patients undergoing reverse shoulder arthroplasty for acute proximal humeral fractures, anatomic tuberosity healing improves objective and subjective outcomes [2]. Percutaneous treatment of selected proximal humeral fractures results in predictable union and good clinical results with a low rate of complications [62]. Shoulder function was restored to preinjury levels for most patients after open reduction and internal fixation of unilateral displaced 3- or 4-part fractures, and osteoporosis may not be regarded as a contraindication for this treatment [53]. Clinical results at 1-year follow-up confirm the advantage of applying a new intramedullary support nail and plate system to 3- or 4-part proximal humeral fractures in older patients [3].

Implant Selection: Patients with acute proximal humeral fractures who undergo reverse shoulder arthroplasty appear to achieve superior 5-year functional outcomes compared with patients who undergo hemiarthroplasty [6]. Available literature suggests that reverse shoulder arthroplasty performed to address complex proximal humeral fractures might result in more favorable clinical outcomes than hemiarthroplasty performed for the same indication [26]. Patients undergoing shoulder hemiarthroplasty for acute proximal humeral fractures may achieve satisfactory long-term pain relief, though overall shoulder motion results are less predictable [1]. Primary shoulder hemiarthroplasty for proximal humeral fracture is associated with satisfactory prosthetic survival at an average of 6.3 years [14]. With narrow indications, use of a specific fracture stem and adequate tuberosity management, successful radiographic and functional results are presented after a mean follow-up of 4.8 years after hemiarthroplasty for primary nonreconstructable humeral head fractures [65].

Other Considerations: Patients undergoing shoulder hemiarthroplasty for acute proximal humeral fractures may achieve satisfactory long-term pain relief, though overall shoulder motion results are less predictable [1]. In elderly patients undergoing reverse shoulder arthroplasty for acute proximal humeral fractures, anatomic tuberosity healing improves objective and subjective outcomes [2].

Complications

Infection (PJI): Specific incidence rates for periprosthetic joint infection are not detailed in the provided evidence base. However, in-hospital complications are more likely to occur after reverse shoulder arthroplasty than after locked plating for proximal humeral fractures [21]. The majority of unplanned hospital readmissions following surgical treatment of proximal humerus fractures are associated with medical diagnoses rather than surgical site issues [19].

Aseptic loosening: Primary shoulder hemiarthroplasty for proximal humeral fracture is associated with satisfactory prosthetic survival at an average of 6.3 years [14].

Instability: Patients undergoing arthroplasty for acute proximal humerus fractures may achieve satisfactory long-term pain relief, but overall shoulder motion results are less predictable [1]. In elderly patients undergoing reverse shoulder arthroplasty for acute proximal humeral fractures, anatomic tuberosity healing improves objective and subjective outcomes [2].

Periprosthetic fracture: Specific incidence rates for periprosthetic fracture are not detailed in the provided evidence base.

Thromboembolism: Specific incidence rates for thromboembolism are not detailed in the provided evidence base.

Patellar / Extensor-mechanism: This category is not applicable to shoulder arthroplasty.

Stiffness / Arthrofibrosis: Patients undergoing arthroplasty for acute proximal humerus fractures may achieve satisfactory long-term pain relief, but overall shoulder motion results are less predictable [1].

Nerve palsy: Specific incidence rates for nerve palsy are not detailed in the provided evidence base.

Wound complications: Specific incidence rates for wound complications are not detailed in the provided evidence base.

Polyethylene wear: Specific incidence rates for polyethylene wear are not detailed in the provided evidence base.

Other Considerations: Elderly patients requiring admission after sustaining a proximal humeral fracture are frail and subject to a greater-than-average risk of mortality for their age [4]. Mortality at 1 year for fragility proximal humerus fractures is universally high regardless of risk factors [15]. Patients sustaining a proximal humeral fracture have a significantly higher risk of mortality up to one year after the injury compared with the general population [25]. Patients with acute proximal humeral fractures who undergo reverse shoulder arthroplasty (RSA) achieve superior 5-year functional outcomes compared with patients who undergo hemiarthroplasty [6]. Patients undergoing initial nonoperative management for proximal humeral fractures have worse functional outcomes and higher complication rates than those undergoing acute reverse total shoulder arthroplasty (rTSA) [5]. Surgery for complex proximal humeral fractures leads to overall good long-term outcomes but is associated with high overall complication and reoperation rates [24]. Short-term complication rates for both fixation and arthroplasty have decreased compared with recent historic norms [27].

Recovery

Light activity (weeks): Evidence does not specify a precise week range for light activity, driving, or desk work. However, short and long periods of immobilization yield similar results for nonoperatively treated fractures, independent of the fracture pattern [20]. For operative cases, timing of surgery did not affect Oxford Shoulder Score at any stage of follow-up, irrespective of age or fracture type [80].

Full activity (months): The evidence does not define a specific month range for full activity or return to manual work. Clinical results at 1-year follow-up confirm the advantage of applying a new intramedullary support nail and plate system to 3- or 4-part proximal humeral fractures in older patients [3]. Patients with acute proximal humeral fractures who undergo reverse shoulder arthroplasty appear to achieve superior 5-year functional outcomes compared with patients who undergo hemiarthroplasty [6]. Long-term treatment with reverse shoulder arthroplasty for displaced 3- or 4-part proximal humerus fractures provides better functional outcomes compared to nonoperative treatment, a difference attributed to the deterioration of functional outcomes of the nonoperative treatment over time [63].

Complete recovery / outcome plateau (months): Patients undergoing arthroplasty for acute proximal humeral fractures may achieve satisfactory long-term pain relief, though overall shoulder motion results are less predictable [1]. Primary shoulder hemiarthroplasty for proximal humeral fracture is associated with satisfactory prosthetic survival at an average of 6.3 years [14]. In elderly patients undergoing reverse shoulder arthroplasty for acute proximal humeral fractures, anatomic tuberosity healing improves objective and subjective outcomes [2]. Despite a delayed diagnosis of more than one year, osteotomy and realignment of a displaced fracture of the lesser tuberosity was successful and enhanced overall shoulder function in two adolescent patients [17].

Rehabilitation protocol: The evidence does not detail specific phasing, weight-bearing limits, or sling removal timing. Nonoperative treatment of proximal humeral fractures produces considerable variation in shoulder-specific and general health outcomes at 1 year, and a substantial proportion of patients have poor perceived functional outcomes [13]. Patients who undergo initial nonoperative management have worse functional outcomes and higher complication rates than those who undergo acute reverse total shoulder arthroplasty for proximal humeral fractures [5].

Functional milestones: Validated outcome trajectories indicate that elderly patients requiring admission after sustaining a proximal humeral fracture are frail and subject to a greater-than-average risk of mortality for their age [4]. Mortality at 1 year for fragility proximal humerus fractures is universally high regardless of risk factors [15]. In most studies of proximal humeral fractures, only 1 or 2 patients experiencing an alternative outcome or lost to follow-up would change the conclusions for the dichotomous outcome studied [16]. Surgery for complex proximal humeral fractures leads to overall good long-term outcomes with high overall complication and reoperation rates [24]. Fractures of the proximal humerus follow characteristic patterns [7]. This is the largest long-term follow-up study of acute proximal humeral fractures treated with hemiarthroplasty [9]. The increasing utilization of reverse total shoulder arthroplasty and decreasing short-term complication rates for fixation and arthroplasty alike represent a substantial change compared with recent historic norms in the management of proximal humerus fractures [27].

Other Considerations: No specific recovery-relevant content regarding predictors of return-to-work failure or early ROM selection caveats is present in the provided evidence base beyond the general outcome and mortality data cited above.

Key Evidence

  • [L3] Patients undergoing arthroplasty as treatment of an acute fracture of the proximal humerus may achieve satisfactory long-term pain relief; however, the result for overall shoulder motion is less predictable. (10.1016/j.jse.2007.06.025)
  • [L3] In elderly patients who have undergone a reverse shoulder arthroplasty for acute proximal humeral fractures, anatomic tuberosity healing improves objective and subjective outcomes. (10.1016/j.jse.2018.05.030)
  • [L3] Clinical results at 1-year follow-up confirmed the advantage of applying it to 3- or 4-part proximal humeral fractures in older patients. (10.1186/s12891-022-05998-z)
  • [L3] Elderly patients who require admission after sustaining a proximal humeral fracture are frail and subject to a greater-than-average risk of mortality for their age. (10.1016/j.jse.2019.05.030)
  • [L3] Patients who undergo initial periods of nonoperative management have worse functional outcomes and higher complication rates than those who undergo acute rTSA for proximal humeral fractures. (10.1016/j.jse.2021.06.020)
  • [L3] Patients with acute proximal humeral fractures who undergo RSA appear to achieve superior 5-year functional outcomes compared with patients who undergo hemiarthroplasty. (10.1016/j.jse.2012.03.006)
  • [L4] Fractures of the proximal humerus follow characteristic patterns. (10.1016/j.jse.2017.05.014)
  • [L3] Shoulder rotational ability is improved by systematically repairing the tuberosities around the implant, provided their consolidation is anatomic. (10.1016/j.jse.2012.03.011)
  • [L3] This is the largest long-term follow-up study of acute proximal humeral fractures treated with hemiarthroplasty. (10.1302/0301-620x.103b6.bjj-2020-1753.r1)
  • [L3] A majority of patients with proximal humeral fractures underwent non-operative treatment. (10.1186/s12891-019-2812-9)
  • [L5] Consensus when managing proximal humerus fractures is limited to specific scenarios, whereas lack of consensus still exists in others. (10.1016/j.jse.2024.12.005)
  • [L1] This systematic review highlights significant heterogeneity in the terminology and definitions used to describe complications following non-surgical management of proximal humeral fractures, calling for standardized definitions to improve evidence synthesis. (10.1186/s12891-019-2459-6)
  • [L1] Nonoperative treatment of proximal humeral fractures produces considerable variation in shoulder-specific and general health outcomes at 1 year, and a substantial proportion of patients have poor perceived functional outcomes. (10.2106/jbjs.20.02018)
  • [L2] Primary shoulder hemiarthroplasty for proximal humeral fracture is associated with satisfactory prosthetic survival at an average of 6.3 years. (10.2106/jbjs.l.01115)
  • [L3] Mortality at 1 year for fragility proximal humerus fractures is universally high regardless of risk factors. (10.1016/j.jse.2022.03.006)
  • [L2] In most studies of proximal humeral fractures, only 1 or 2 patients experiencing an alternative outcome or lost to follow-up would change the conclusions for the dichotomous outcome studied. (10.1016/j.jse.2022.01.141)
  • [L4] Despite a delayed diagnosis of more than one year, osteotomy and realignment of the displaced fracture of the lesser tuberosity was successful and enhanced the overall function of the shoulder in these two patients. (10.2106/00004623-199509000-00020)
  • [L3] As the majority of unplanned hospital readmissions were associated with medical diagnoses, it is important to consider patient medical comorbidities before surgical treatment of proximal humerus fractures and during the postoperative care phase. (10.1007/s11999-014-3613-y)
  • [L2] Short and long periods of immobilization yield similar results for nonoperatively treated proximal humeral fractures, independent of the fracture pattern. (10.2106/jbjs.20.02137)
  • [L3] The increased in-hospital risk for major adverse events and surgical complications may moderate the enthusiasm associated with RTSA for proximal humeral fractures in patients 65 years and older. (10.1097/corr.0000000000001776)
  • [L2] In patients presenting with a traumatic shoulder injury with normal radiographs, the anterior bruise sign (ABS) is a highly sensitive and specific clinical aid to identify patients with an occult greater tuberosity fracture. (10.1016/j.jse.2023.07.044)
  • [L5] Most proximal humeral fractures in elderly patients can be treated nonoperatively with good functional outcomes. (10.2106/jbjs.l.01293)
  • [L5] Surgery for complex proximal humeral fractures leads to overall good long-term outcomes with high overall complication and reoperation rates. (10.2106/jbjs.19.01109)
  • [L3] Compared with the general population, patients sustaining a proximal humeral fracture have a significantly higher risk of mortality up to one year after the injury. (10.1302/0301-620x.102b11.bjj-2020-0627.r1)
  • [L1] The available literature suggests that reverse shoulder arthroplasty performed to address complex proximal humeral fractures might result in more favorable clinical outcomes than hemiarthroplasty performed for the same indication. (10.1016/j.jse.2015.08.030)
  • [L3] The increasing utilization of RTSA and decreasing short-term complication rates for fixation and arthroplasty alike represent a substantial change compared even with recent historic norms in the management of proximal humerus fractures. (10.1097/corr.0000000000002391)
  • [L5] Greater tuberosity healing does not seem to impact reverse shoulder arthroplasty biomechanics during abduction or forward flexion; however, it does affect biomechanics during external rotation. (10.1016/j.jse.2019.07.022)
  • [L3] Range of motion and strength thresholds can identify subjects with normal shoulder function. (10.1016/j.jse.2010.06.005)
  • [L5] With minimal and moderate amounts of glenohumeral abduction, glenohumeral joint forces are significantly displaced superiorly. (10.1016/j.jse.2007.06.017)
  • [L3] The authors recommend performing the measurement at the insertion of the deltoid muscle in a 90° abduction position in the scapula plane. (10.1186/s12891-019-2795-6)
  • [L3] Dominance of the affected shoulder has no influence and should not be used to make treatment decisions. (10.1016/j.jse.2014.10.006)
  • [L4] The study demonstrates variability in the glenopolar angle with increased AP rotational offset of the shoulder radiograph, revealing inaccuracies even at an institution with an established protocol. (10.1302/0301-620x.95b8.30631)
  • [L5] Varus and antecurvatum proximal humerus deformities as small as 15 degrees were associated with statistically significant alterations in glenohumeral joint mechanics. (10.5435/jaaos-d-20-00555)
  • [L5] Vertical abduction has the greatest effect on axillary nerve position, while horizontal glenohumeral forward flexion and humeral rotation have little effect. (10.1016/j.jse.2008.12.001)
  • [L5] The control volume is an important anatomic and functional area of the proximal humerus. (10.1016/j.jse.2017.12.004)
  • [L4] Nonsurgical management of proximal humerus fractures decreased during the study period. (10.1016/j.jhsa.2020.03.022)
  • [L1] Treatment with reverse shoulder arthroplasty provides superior functional outcomes compared with conservative treatment for patients presenting with an acute proximal humeral fracture. (10.1016/j.jse.2024.02.023)
  • [L1] This trial found no significant difference in clinical outcomes at 2 years between surgery and non-operative treatment in patients 60 years of age or older with displaced 2-part fractures of the proximal humerus. (10.1371/journal.pmed.1002855)
  • [L3] The new classification system with emphasis on the qualitative aspects of proximal humeral fractures showed high reliability when based on a standardized imaging protocol including computed tomography scans. (10.1016/j.jse.2015.08.006)
  • [L5] Most pediatric patients with proximal humerus fractures have favorable results, and complications are infrequent. (10.5435/jaaos-d-14-00033)
  • [L5] Treatment for proximal humerus fractures remains controversial, with nonsurgical management demonstrating successful outcomes and union rates greater than 90%. (10.5435/jaaos-d-24-01073)
  • [L3] Nonsurgical treatment should have a more prominent role in the treatment of proximal humeral fractures. (10.1016/j.jse.2011.01.025)
  • [L1] Shoulder function was restored to preinjury levels for most patients, and osteoporosis may not be regarded as a contraindication for this treatment. (10.1016/j.jse.2022.07.008)
  • [L5] Reverse shoulder arthroplasty is a powerful tool for managing proximal humerus fracture sequelae when joint-preserving options are not optimal, provided there is careful management of the tuberosities and understanding of associated pearls and pitfalls. (10.5435/jaaos-d-23-00740)
  • [L2] Prevention of local complications, in particular those leading to severe varus deviation, appears essential to improve shoulder function after a proximal humeral fracture. (10.1016/j.jse.2011.06.009)
  • [L3] The HGLS classification is a reliable method of describing fractures of the proximal humerus compared with the Neer and AO systems. (10.1016/j.jse.2012.09.018)
  • [L5] Surgical treatment of proximal humerus fractures remains far from straightforward, with unpredictable outcomes where factors associated with poor results include being a woman, four-part fracture dislocation, and absence of metaphyseal head extension. (10.1097/corr.0000000000002242)
  • [L4] The revised Neer classification covers 98% of all proximal humeral fractures and is appropriate for clinical practice. (10.1016/j.jse.2009.01.018)
  • [L1] The review identified a wide range of outcome measures used in proximal humeral fracture studies, but found limited evidence regarding their psychometric properties in this specific population. (10.1016/j.jse.2010.10.028)
  • [L4] Classifications of proximal humeral fractures using the Neer system based on CT scans and plain radiographs are not very reliable or reproducible due to difficulty in determining which segments are fractured. (10.2106/00004623-199609000-00012)
  • [L4] Percutaneous treatment of selected proximal humeral fractures results in predictable union and good clinical results with a low rate of complications. (10.1016/j.jse.2006.09.006)
  • [L1] Long-term treatment with RSA for displaced 3- or 4-part proximal humerus fractures provides better functional outcomes compared to nonoperative treatment, a difference attributed to the deterioration of functional outcomes of the nonoperative treatment over time. (10.1016/j.jse.2024.09.032)
  • [L4] With narrow indications, use of a specific fracture stem and adequate tuberosity management, successful radiographic and functional results are presented after a mean follow-up of 4.8 years after hemiarthroplasty for primary nonreconstructable humeral head fractures. (10.1016/j.jse.2023.02.118)
  • [L1] RTSA performed for acute 3- and 4-part proximal humeral fractures yields overall worse clinical outcomes and active ROM compared with RTSA performed for elective indications. (10.1016/j.jse.2021.07.014)
  • [L1] We observed no clear benefits in treating patients 65 years or older with four-part fractures of the proximal humerus with either hemiarthroplasty or nonoperative treatment. (10.1007/s11999-012-2531-0)
  • [L3] This implies that the inherent nature of medial comminution of proximal humeral fracture may lead to inferior radiographic outcomes. (10.1186/s13018-022-03337-5)
  • [L4] Undisplaced greater tuberosity fractures can be managed non-operatively with good results, but patients with persistent post-traumatic shoulder pain and limitation of function warrant MRI investigation to identify occult fractures. (10.1186/s12891-018-2225-1)
  • [L3] There is relevant variability in displacement measurements between shoulder radiographs and CT scans in the coronal plane, with nearly 30% of cases suggesting surgical treatment on radiographs being reclassified for conservative treatment based on CT findings. (10.1016/j.jse.2016.05.016)
  • [L5] The routine use of 3D-printed models may not be beneficial for classifying proximal humeral fracture patterns beyond the information gained from currently available imaging modalities, and their use as the sole determinant for recommending surgical intervention should be avoided at this time. (10.1097/corr.0000000000002017)
  • [L3] CNNs proficiently rule out proximal humerus fractures on plain radiographs. (10.1302/0301-620x.106b11.bjj-2024-0264.r1)
  • [L4] Missed posterior dislocation of the shoulder after intramedullary fixation of proximal humeral fractures is an extremely rare injury that can be missed due to inadequate initial and postoperative x-ray images and incorrect interpretation. (10.1016/j.jse.2008.10.020)
  • [L1] Timing of surgery did not affect Oxford Shoulder Score at any stage of follow-up, irrespective of age or fracture type. (10.1302/0301-620x.102b1.bjj-2020-0546.r1)

See Also

References

[1] Shoulder hemiarthroplasty for acute fractures of the proximal humerus: A minimum five-year follow-up. Journal of Shoulder and Elbow Surgery. 2008. DOI: 10.1016/j.jse.2007.06.025

[2] How the greater tuberosity affects clinical outcomes after reverse shoulder arthroplasty for proximal humeral fractures. Journal of Shoulder and Elbow Surgery. 2018. DOI: 10.1016/j.jse.2018.05.030

[3] Technique and clinical results of a new intramedullary support nail and plate system for fixation of 3- or 4- part proximal humeral fractures in older adults. BMC Musculoskeletal Disorders. 2022. DOI: 10.1186/s12891-022-05998-z

[4] Mortality after inpatient stay for proximal humeral fractures. Journal of Shoulder and Elbow Surgery. 2020. DOI: 10.1016/j.jse.2019.05.030

[5] Minimum 2-year outcomes of reverse total shoulder arthroplasty for fracture: how does acute arthroplasty compare with salvage?. Journal of Shoulder and Elbow Surgery. 2022. DOI: 10.1016/j.jse.2021.06.020

[6] Functional outcomes of reverse shoulder arthroplasty compared with hemiarthroplasty for acute proximal humeral fractures. Journal of Shoulder and Elbow Surgery. 2013. DOI: 10.1016/j.jse.2012.03.006

[7] Fracture line morphology of complex proximal humeral fractures. Journal of Shoulder and Elbow Surgery. 2017. DOI: 10.1016/j.jse.2017.05.014

[8] Improvement in shoulder rotation in complex shoulder fractures treated by reverse shoulder arthroplasty. Journal of Shoulder and Elbow Surgery. 2013. DOI: 10.1016/j.jse.2012.03.011

[9] Ten-year follow-up of stemmed hemiarthroplasty for acute proximal humeral fractures. The Bone & Joint Journal. 2021. DOI: 10.1302/0301-620x.103b6.bjj-2020-1753.r1

[10] Readmissions, revisions, and mortality after treatment for proximal humeral fractures in three large states. BMC Musculoskeletal Disorders. 2019. DOI: 10.1186/s12891-019-2812-9

[11] Consensus statement on the treatment of proximal humerus fractures: a Delphi approach by the Neer Circle of the American Shoulder and Elbow Surgeons. Journal of Shoulder and Elbow Surgery. 2025. DOI: 10.1016/j.jse.2024.12.005

[12] Complications after non-surgical management of proximal humeral fractures: a systematic review of terms and definitions. BMC Musculoskeletal Disorders. 2019. DOI: 10.1186/s12891-019-2459-6

[13] Functional Outcome After Nonoperative Treatment of a Proximal Humeral Fracture in Adults. Journal of Bone and Joint Surgery. 2021. DOI: 10.2106/jbjs.20.02018

[14] Comparison of Hemiarthroplasty and Reverse Arthroplasty for Treatment of Proximal Humeral Fractures. Journal of Bone and Joint Surgery. 2013. DOI: 10.2106/jbjs.l.01115

[15] Morbidity and mortality of fragility proximal humerus fractures: a retrospective cohort study of patients presenting to a level one trauma center. Journal of Shoulder and Elbow Surgery. 2022. DOI: 10.1016/j.jse.2022.03.006

[16] Fragility of randomized controlled trials on treatment of proximal humeral fracture. Journal of Shoulder and Elbow Surgery. 2022. DOI: 10.1016/j.jse.2022.01.141

[17] Isolated avulsion fracture of the lesser tuberosity of the humerus in adolescents. A report of two cases.. The Journal of Bone & Joint Surgery. 1995. DOI: 10.2106/00004623-199509000-00020

[19] Hospital Readmissions After Surgical Treatment of Proximal Humerus Fractures: Is Arthroplasty Safer Than Open Reduction Internal Fixation?. Clinical Orthopaedics & Related Research. 2014. DOI: 10.1007/s11999-014-3613-y

[20] One Versus 3-Week Immobilization Period for Nonoperatively Treated Proximal Humeral Fractures. Journal of Bone and Joint Surgery. 2021. DOI: 10.2106/jbjs.20.02137

[21] In-hospital Complications Are More Likely to Occur After Reverse Shoulder Arthroplasty Than After Locked Plating for Proximal Humeral Fractures. Clinical Orthopaedics & Related Research. 2021. DOI: 10.1097/corr.0000000000001776

[22] A new clinical sign to detect radiologically occult greater tuberosity fractures. Journal of Shoulder and Elbow Surgery. 2024. DOI: 10.1016/j.jse.2023.07.044

[23] Proximal Humeral Fracture Treatment in Adults. Journal of Bone and Joint Surgery. 2014. DOI: 10.2106/jbjs.l.01293

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[25] Mortality after a proximal humeral fracture. The Bone & Joint Journal. 2020. DOI: 10.1302/0301-620x.102b11.bjj-2020-0627.r1

[26] Hemiarthroplasty versus reverse shoulder arthroplasty for treatment of proximal humeral fractures: a meta-analysis. Journal of Shoulder and Elbow Surgery. 2016. DOI: 10.1016/j.jse.2015.08.030

[27] Short-term Complications for Proximal Humerus Fracture Surgery Have Decreased: An Analysis of the National Surgical Quality Improvement Program Database. Clinical Orthopaedics & Related Research. 2022. DOI: 10.1097/corr.0000000000002391

[28] The role of greater tuberosity healing in reverse shoulder arthroplasty: a finite element analysis. Journal of Shoulder and Elbow Surgery. 2020. DOI: 10.1016/j.jse.2019.07.022

[29] Does objective shoulder impairment explain patient-reported functional outcome? A study of proximal humerus fractures. Journal of Shoulder and Elbow Surgery. 2011. DOI: 10.1016/j.jse.2010.06.005

[30] Neer Award 2006: Biomechanical assessment of inferior tuberosity placement during hemiarthroplasty for four-part proximal humeral fractures. Journal of Shoulder and Elbow Surgery. 2008. DOI: 10.1016/j.jse.2007.06.017

[35] Evaluation of the Constant score: which is the method to assess the objective strength?. BMC Musculoskeletal Disorders. 2019. DOI: 10.1186/s12891-019-2795-6

[37] Does fracture of the dominant shoulder have any effect on functional and quality of life outcome compared with the nondominant shoulder?. Journal of Shoulder and Elbow Surgery. 2015. DOI: 10.1016/j.jse.2014.10.006

[38] The assessment of scapular radiographs. The Bone & Joint Journal. 2013. DOI: 10.1302/0301-620x.95b8.30631

[40] Altered Glenohumeral Biomechanics in Proximal Humeral Fracture Malunion. Journal of the American Academy of Orthopaedic Surgeons. 2020. DOI: 10.5435/jaaos-d-20-00555

[43] Effects of shoulder position on axillary nerve positions during the split lateral deltoid approach. Journal of Shoulder and Elbow Surgery. 2009. DOI: 10.1016/j.jse.2008.12.001

[44] A morphovolumetric study of head malposition in proximal humeral fractures based on 3-dimensional computed tomography scans: the control volume theory. Journal of Shoulder and Elbow Surgery. 2018. DOI: 10.1016/j.jse.2017.12.004

[46] Cost-Minimization Analysis and Treatment Trends of Surgical and Nonsurgical Treatment of Proximal Humerus Fractures. The Journal of Hand Surgery. 2020. DOI: 10.1016/j.jhsa.2020.03.022

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[49] Classification of proximal humeral fractures based on a pathomorphologic analysis. Journal of Shoulder and Elbow Surgery. 2016. DOI: 10.1016/j.jse.2015.08.006

[50] Evaluation and Management of Pediatric Proximal Humerus Fractures. Journal of the American Academy of Orthopaedic Surgeons. 2015. DOI: 10.5435/jaaos-d-14-00033

[51] Contemporary Management of Proximal Humeral Fractures. Journal of the American Academy of Orthopaedic Surgeons. 2025. DOI: 10.5435/jaaos-d-24-01073

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[53] Osteoporosis does not affect bone mineral density change in the proximal humerus or the functional outcome after open reduction and internal fixation of unilateral displaced 3- or 4-part fractures at 12-month follow-up. Journal of Shoulder and Elbow Surgery. 2023. DOI: 10.1016/j.jse.2022.07.008

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[55] Path analysis of factors for functional outcome at one year in 463 proximal humeral fractures. Journal of Shoulder and Elbow Surgery. 2011. DOI: 10.1016/j.jse.2011.06.009

[56] A comprehensive classification of proximal humeral fractures: HGLS system. Journal of Shoulder and Elbow Surgery. 2013. DOI: 10.1016/j.jse.2012.09.018

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[65] Is there still a place for anatomic hemiarthroplasty in patients with high functional demands in primary, nonreconstructable proximal humeral fractures? A clinical and radiographic assessment. Journal of Shoulder and Elbow Surgery. 2023. DOI: 10.1016/j.jse.2023.02.118

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