The modified axillary view of the shoulder, a painless alternative

A pictorial presentation and the clinical use of the modified trauma axial (MTA) shoulder x-ray view

Anteroposterior (AP) and lateral shoulder projections are routinely performed as part of a post-reduction shoulder x-ray series in the emergency department (ED). Research has shown that these projections alone are insufficient to demonstrate post-dislocation injuries, particularly Hill-Sachs and Bankart lesions. These concomitant pathologies are best demonstrated on axial shoulder projections but are difficult to obtain in trauma patients with limited range of motion. The diagnostic quality and the pathology demonstrated by different projections is crucial so that doctors and other ED staff can triage patients appropriately, radiologists can report on the presence or absence of post-dislocation shoulder injuries, and the orthopaedic team can plan for follow-up or treatment. Different modified axial views were reported to improve the post-dislocation pathology sensitivity in the shoulder series. However, all of these shoulder axial views require patient movement. The modified trauma axial (MTA) is an alternative projection that is suitable for trauma patients that does not depend on patient movement. This paper presents several cases where the MTA shoulder projection had clinical importance when used as part of the post-reduction shoulder series in the ED or radiology department.

The Clinical Utility of Additional Axillary and Velpeau Radiographs in the Evaluation of Suspected Shoulder Trauma

OBJECTIVES

To investigate the clinical utility of additional axillary or Velpeau views in evaluating potential shoulder trauma after a standard radiograph series of anteroposterior, Grashey, and/or trans-scapular views.

DESIGN

Retrospective study.

SETTING

Level I academic medical center.

PATIENTS

All patients in a 10-year span who received an initial shoulder radiograph series followed by additional axillary/Velpeau views within 24 hours.

MAIN OUTCOME MEASUREMENTS

The clinical utility of the additional axillary/Velpeau views, including the final diagnosis and treatment plan, as ascertained through examination of radiology reports, progress notes, and radiograph images.

RESULTS

A total of 271 cases were reviewed, with 35 patients being excluded from the final cohort because they received post-treatment radiographs to confirm a successful therapeutic outcome. The additional axillary/Velpeau views did not affect clinical decision making in 230 (97.5%) of the remaining 236 cases. All 6 patients whose care benefitted from the additional views carried the diagnosis of shoulder instability, accounting for 40% of this diagnostic group. The additional views confirmed an equivocal finding in 5 of these 6 cases and changed the diagnosis (demonstrating a posterior dislocation that was not evident on initial radiographs) and treatment plan (leading to a closed glenohumeral reduction procedure) in the other case.

CONCLUSIONS

Additional axillary/Velpeau views of suspected shoulder trauma rarely led to a change in the final treatment plan, except in patients in which a definitive diagnosis of stability or instability could not be made based on initial radiographs. A cost/benefit analysis is required to weigh the cost of additional radiographs with the benefit of capturing infrequent yet serious dislocations (usually posterior).

LEVEL OF EVIDENCE

Diagnostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Predictive value of valgus head-shaft angle in identifying Neer 4-part proximal humerus fractures. A radiographic and CT-scan analysis of 120 cases

Background and aim of the work:

Understanding the fracture morphology and its relation to the expected outcome and risk of complications is fundamental for proximal humerus fractures (PHFs) management. Most Neer 3- and 4-part fractures may deserve surgical treatment. Unfortunately, plain x-rays may not be able to differentiate between a 3- or 4-part fractures unless an axillary or analogue projection is carried out. Aim of the present study is to evaluate whether a high valgus head-shaft angle degree is predictive of a Neer 4-part rather than a 3-part fracture.

Methods:

The study included 120 3-(75 cases) and 4-(45 cases) part PHFs (valgus displaced in 98 cases), M:F ratio = 1:2.6, mean age 65.7 years, classified on CT scan images. The humeral head shaft angle was calculated on AP x-rays and statistically correlated with 3 and 4-part fractures to identify values predictive of 4-part fracture.

Results:

Valgus head/shaft angle was significantly higher in 4-part fractures, especially in the valgus displaced group (p < 0.001). A cutoff value of 168.5° was identified as predictive of a 4-part fracture with a sensibility of 74% and specificity of 78%. Increasing by 1 degree the humeral head-shaft angle, the chance to have a 4-part fracture increases of 3% in the whole population and of 11% in the valgus sub-group.

Conclusion:

The severity of PHF can be predicted analysing valgus head shaft angle on AP x-rays with a sensibility of 74% and specificity of 78% in identifying a 4-part fracture with a cutoff value of 168.5°.

Missed posterior shoulder fracture dislocations: a new protocol from a London major trauma centre

Background

A high incidence of missed posterior shoulder dislocations is widely recognised in the literature. Concern was raised by the upper limb multidisciplinary team at a London major trauma centre that these missed injuries were causing serious consequences due to the need for surgical intervention and poor functional outcome.

Objective

To identify factors contributing to missed diagnosis and propose solutions.

Methods

A local quality improvement report was performed investigating time from admission to diagnosis of simple posterior dislocations and fracture dislocations over a 5-year period. Factors contributing to a delayed diagnosis were analysed.

Results

The findings supported current evidence: a posterior shoulder dislocation was more often missed if there was concurrent fracture of the proximal humerus. Anteroposterior and scapular Y view radiographs were not always diagnostic for dislocation. Axial views were more reliable in assessment of the congruency of the joint and were associated with early diagnosis and appropriate treatment of the injury.

Discussion

As a result of these findings a new protocol was produced by the orthopaedic and radiology departments and distributed to our emergency department practitioners and radiography team. The protocol included routine axial or modified trauma axial view radiographs for all patients attending the emergency department with a shoulder injury, low clinical suspicion for dislocation and a low threshold for CT scan. Reaudit and ongoing data collection have shown significant increase in axial view radiographs and improved diagnosis.

The Axillary View Typically Does Not Contribute to Decision Making in Care for Proximal Humeral Fractures

BACKGROUND

Convention dictates that an axillary view be obtained when evaluating proximal humerus fractures (PHF). However, the axillary view is frequently omitted because of pain and technical considerations. Furthermore, its diagnostic utility is unclear in this setting.

QUESTIONS/PURPOSES

The purpose of this study was to (1) determine the rate of obtaining an adequate axillary X-ray and complete shoulder series at a level I trauma center, (2) understand the cost of ordering and attempting an axillary radiograph, and (3) determine if axillary radiographs influence the management of PHF.

PATIENTS AND METHODS

PHF treated between 2009 and 2011 that were ordered for an AP, scapular Y, and axillary view was identified. The types of radiographs actually obtained were recorded. The cost of obtaining three views and a single view of the shoulder with X-ray was determined. Lastly, three surgeons reviewed 42 PHF, both with and without an axillary view (AV), and treatment recommendations were compared.

RESULTS

30% of PHF in this series had an adequate axillary view, and 14% received a complete trauma series. No factors could be identified that were associated with successfully obtaining an axillary view. Reviewers demonstrated substantial intraobserver reliability (κ = 0.759-0.808) regarding treatment recommendations for PHF with and without the axillary view. The addition of the AV had minimal influence on treatment recommendations.

CONCLUSION

Considering that the axillary view for PHF is painful, labor-intensive, costly, and does not appear to provide additional diagnostic value, orthopedic surgeons can consider foregoing the use of the axillary view when evaluating and treating PHF, particularly if other advanced imaging is utilized.

Indications for computed tomography (CT-) diagnostics in proximal humeral fractures: a comparative study of plain radiography and computed tomography

BACKGROUND

Precise indications for computed tomography (CT) in proximal humeral fractures are not established. The purpose of this study was a comparison of conventional radiographic views with different CT reconstructions with 2 D and 3 D imaging to establish indications for additional CT diagnostics depending on the fractured parts.

METHODS

In a prospective diagnostic study in two level 1 trauma centers, 44 patients with proximal humeral fractures were diagnosed with conventional X-rays (22 AP + axillary views, 22 AP + scapular Y-views) and CT (multi-planar reconstruction (MPR) and maximum intensity projection (MIP)) with 2 D and 3 D imaging. 3 observers assessed the technical image quality, the assessment of the relevant anatomical structures (2-sample-t-test) and the percentage of the osseous overlap of the proximal humerus (Welch-test) using a scoring system. The quality of the different diagnostic methods was assessed according to the number of fractured parts (Bonferroni-Holm adjustment).

RESULTS

There was significantly more overlap of the fractured region on the scapular Y-views (mean 71.5%, range 45-90%) than on axillary views (mean 56.2%, range 10.5-100%). CT-diagnostics allowed a significantly better assessment of the relevant structures than conventional diagnostics (p < 0.05) independently of the fracture severity (two-, three-, and four-part fractures).

CONCLUSION

Conventional X-rays with AP view and a high-quality axillary view are useful for primary diagnostics of the fracture and often but not always show a clear presentation of the relevant bony structures such as both tuberosities, the glenoid and humeral head. CT with thin slices technology and additional 3 D imaging provides always a clear presentation of the fractured region. Clinically, a CT should be performed--independently of the number of fractured parts--when the proximal humerus and the shoulder joint are not presented with sufficient X-ray-quality to establish a treatment plan.