Traumatic posterior glenohumeral dislocation: classification, pathoanatomy, diagnosis, and treatment

Arthroscopic treatment of posterior shoulder instability: a systematic review

PURPOSE

We performed a systematic review of the literature to determine the early and midterm outcomes of arthroscopic stabilization for posterior shoulder instability.

METHODS

We searched PubMed, Embase, and the Cochrane Database of Systematic Reviews for related articles published in the English language. The 2 authors selected studies for inclusion or exclusion. The inclusion criteria included a minimum of 1 year of follow-up, with at least 20 patients in the study population.

RESULTS

We included 6 studies, with a total of 387 patients (396 shoulders). All studies were retrospective, Level IV studies, except for 1 prospective study (Level II). In 81.06% of cases, patients reported a significant traumatic episode. The mean follow-up period was 44.4 months, and the mean recurrence rate was 5.37%. Most of the patients were able to return to sport (mean, 92.5%).

CONCLUSIONS

The early and midterm results of arthroscopic stabilization of the shoulder for posterior instability are promising. Most of the patients were satisfied with the results of surgery and were able to return to sport. Larger studies and more prospective randomized trials are needed to confirm these findings.

LEVEL OF EVIDENCE

Level IV, systematic review of 1 Level II study and 5 Level IV studies.

A case of posterior shoulder dislocation with ipsilateral humeral shaft fracture

Posterior shoulder dislocations are rare and represent 2–5% of all traumatic shoulder dislocation. A combination of this injury with ipsilateral humeral shaft fracture is extremely rare event. We here report a case of posterior shoulder dislocation with ipsilateral fracture shaft of humerus following road traffic accident. Through this report, we highlight the rarity of the condition and review the available literature on the subject. We also emphasize the importance of complete physical and radiological examination when dealing with such cases to ensure early detection and its subsequent treatment.

Misses and errors in upper extremity trauma radiographs

OBJECTIVE

The article reviews a select group of traumatic upper extremity injuries that can be easily misinterpreted on radiographs.

CONCLUSION

The awareness of these specific injuries and an understanding of their underlying pathophysiology and the role that radiographs can play in their evaluation will give the reader the best opportunity to make the important imaging findings and guide appropriate treatment.

[Surgical treatment of posterior shoulder dislocation: importance of arthroscopy]

OBJECTIVE

Posterior dislocations of the shoulder represent a rare injury with frequently occurring soft tissue and/or bony concomitant lesions such as the reverse Hill-Sachs lesion and the dorsal labrum tear. For the combination of these injuries, no evidence-based therapeutic recommendations exist.

AIM OF STUDY

Reflecting on two clinical cases and the current literature data, options for the treatment of combined osseous and soft tissue injuries due to posterior dislocation of the shoulder are presented.

METHODS

We report two cases of fresh traumatic first-time posterior dislocations that were each explored arthroscopically and subsequently operated using an open technique. In the first case, we performed refixation of the labrum, followed by open osteosynthesis with bone substitution. Treatment of the second case included diagnostic arthroscopy and - after a frustrating attempt to elevate the defect in an arthroscopically assisted retrograde technique - open reconstruction of the humeral head with an allograft.

RESULTS

In both cases good clinical outcomes with Constant scores of 79 and 86 points at the 16- and 12-month follow-ups, respectively, were achieved. Radiologically complete integration of the used materials was found.

CONCLUSION

These cases show that for the operative treatment of fresh, traumatic posterior shoulder dislocation, it is useful to explore the joint arthroscopically to identify concomitant injuries of the labrum and if necessary treat them. The bony pathology of the humeral head can subsequently be addressed in an open technique, whereby the appropriate treatment should be chosen based on the size of the defect.

Traumatic shoulder injuries: a force mechanism analysis-glenohumeral dislocation and instability

OBJECTIVE

Acute traumatic glenohumeral dislocation is one of the most commonly encountered shoulder injuries and can produce a complex combination of associated bony and soft-tissue injuries, the full extent of which is often initially underappreciated. The objectives of this article are to illustrate the relevant anatomy of the shoulder and provide a more intuitive understanding of the complex biomechanics of traumatic glenohumeral instability through the use of 3D modeling and animation to improve the radiologist's awareness of some of the most common injury patterns, and potentially improve the detection of associated injuries. Emphasis is placed on the most critical injuries to determine the ultimate treatment modality, and imaging recommendations are provided.

CONCLUSION

Understanding the force mechanisms responsible for traumatic glenohumeral dislocation can potentially improve detection of associated secondary injuries, which can guide more effective injury classification and ultimately direct more appropriate and timely intervention.

Revision posterior shoulder stabilization

BACKGROUND

Revision arthroscopic posterior glenohumeral stabilization requires a thorough understanding of the static and dynamic stabilizers of the glenohumeral joint. The evaluation of these patients is complex but critical given the variety of possible underlying lesions.

METHOD

We reviewed the literature surrounding recurrent and revision posterior instability biomechanics, etiology, evaluation, treatment, and outcomes. We also reviewed our own database of posterior instability cases and isolated revision procedures to review our own outcomes and to highlight overall concepts.

DISCUSSION/CONCLUSION

Although other authors have argued that performing a revision procedure indicates for an open procedure and osseous augmentation, our experience has been that revision posterior stabilization arthroscopic soft-tissue repair alone may be indicated in selected patients. After identification of posterior glenoid bone loss/effective retroversion and mechanical failure of prior repairs, the majority of the patients with recurrence of posterior instability likely have either recurrent or persistent labral pathology or patulous capsules with occult multi-directional instability primarily manifesting in the posterior direction. These patients are best served with capsular shift, reefing, and plication, often requiring 180-270° repair and 4 or greater suture anchors. Because of significant heterogeneity in the clinical outcomes reported to date further research will be necessary to define the clinical outcomes in revision posterior stabilization.

Arthroscopic treatment of a reverse hill-sachs lesion

Acute traumatic posterior shoulder instability is a rare injury. Such injuries can result in significant bone defects of the anterior humeral head that require surgical intervention. In the past, small to medium defects have been treated by a soft-tissue or bone transfer into the lesion. We present an arthroscopic technique for addressing these lesions in which the middle glenohumeral ligament is sutured into the defect, thereby making it an extra-articular defect and preventing it from engaging the posterior glenoid.

Incidence of associated injury in posterior shoulder dislocation: systematic review of the literature

OBJECTIVE

Posterior shoulder dislocations are rare and often missed. Classically associated with seizures, very little is known about the incidence and type of associated injuries. Unfortunately, the majority of the literature consists of incidental reports or small case series. Our goal was to increase the strength of available data by performing a systematic review.

DATA SOURCES

We searched EMBASE and PubMed for the terms "posterior shoulder dislocation." Our inclusion criteria were articles in either English or French with the words "posterior" and "dislocation" in the abstract or title. All reports of chronic cases or instability as well as those without patient information were excluded. Data regarding demographics, etiology, investigations, associated injuries, treatments, and outcomes were extracted. All data were analyzed by using SPSS 18.0 (IBM, Chicago, IL).

RESULTS

A total of 766 articles were found of which 108 were retained for analysis. A total of 475 patients (543 shoulders) were compiled. Seizures were reported in 34% of cases. A majority of dislocations (65%) had associated injuries. Fracture was most common followed by reverse Hill-Sachs and cuff tears. In the absence of fracture or reverse Hill-Sachs injury, the risk of cuff tear increased nearly fivefold (odds ratio, 4.6; P = 0.016).

CONCLUSION

Our results suggest the amount of associated injuries related to posterior shoulder dislocation is far greater than thought. We propose an investigation algorithm for acute posterior shoulder dislocations.

Risk management and avoiding legal pitfalls in the emergency treatment of high-risk orthopedic injuries

Avoiding legal pitfalls of orthopedic injuries in the emergency department (ED) requires an understanding of certain high-risk injuries, their presentation, evaluation, and disposition. Various pitfalls pertaining to both upper and lower extremity injuries are discussed in detail, with recommendations regarding the history, physical examination, and radiographic techniques that minimize the risk inherent in these injuries. When approaching these injuries in the ED, a high level of suspicion coupled with appropriate evaluation and management will allow the practitioner to avoid mismanagement of these potential pitfall cases.