Case Report

Bedside ultrasound for verification of shoulder reduction

Abstract

Shoulder dislocations are a common complaint in the emergency department. The management of these injuries is well described and often involves procedural sedation. Unfortunately, patients often recover from this sedation before radiographs can verify Successful reduction. We describe 2 patients with glenohumeral dislocations and subsequent reduction immediately verified by bedside ultrasound before the patients’ recovery from procedural sedation. Our experience suggests that ultrasound may reduce the need for repeated sedation, expedite care, and reduce costs.

The Glenohumeral joint is the most commonly dislocated major joint [1]. Typical management involves radiographic imaging followed by reduction. If procedural sedation is used during reduction, the patient often recovers before radiographic confirmation is obtained, necessitating reseda- tion if the reduction was unsuccessful. In this case report, we describe the use of bedside ultrasound to confirm reduction prior to recovery from procedural sedation.

An 83-year-old man presented to our emergency depart- ment (ED) approximately 2 hours after falling on his outstretched arm. On physical examination, his shoulders

were asymmetric with the left appearing “squared off.” His shoulder was tender, and he resisted abduction and rotation.

Radiographs showed the humeral head displaced anterior to the glenoid and inferior to the coracoid process, thus, confirming anterior subcoracoid glenohum- eral Joint dislocation.

The patient underwent procedural sedation using a 100-mg bolus of propofol in a monitored ED bed, and his shoulder was reduced using the traction-counter-traction technique with no complications. A SonoSite MicroMAXX ultrasound machine (SonoSite, Inc, Bothell, Wash) was at the patient’s bedside, and the 60-MHz curved probe (C60) was placed transversely on the patient’s back inferior to the lateral portion of his scapular spine (see Fig. 1A). The transducer was oriented so the head of the humerus was identified adjacent to the posterior glenoid (cf Fig. 1B [dislocated] to Fig. 1C [reduced]).

At this point the patient was taken for a repeat anteroposterior radiograph that verified successful reduction, and the patient was discharged with range of motion exercises, pain control, and follow-up with a local Orthopedic surgeon.

A 50-year-old man was brought in by ambulance after being struck by a car while riding his bike. The patient’s primary complaint was severe shoulder pain and limited range of motion. Radiographs revealed a posterior disloca- tion with the humoral head posterior to the glenoid and inferior to the acromion. The patient was given fentanyl

Fig. 1 A, Transverse posterior illustration of probe position and underlying anatomy. B, Anterior dislocation with humoral head displaced anterior and inferior to glenoid (A). C, Postreduction image with humoral head (B) level with the glenoid.

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100 ug and propofol 100 mg, and his shoulder was reduced using traction and anterior manipulation of the humerus. The C60 bedside ultrasound probe was placed transversely just inferior to his scapular spine to show the humoral head in the glenoid fossa. Postreduction radiographs also verified successful reduction, and the patient was discharged with orthopedic follow-up.

Many shoulder reduction techniques have been described, but methods of confirming reduction have remained limited to plain film techniques [2]. We report the first use of bedside ultrasound to verify glenohumeral joint reduction in the ED. Shoulder reduction is often performed using procedural sedation with short-acting agents to maximize pain control and Muscle relaxation. One important constraint imposed by these medications is that their effect wanes quickly, often before postreduction radiographs can be performed. Espe- cially in patients with a difficult examination, this means that a failed reduction will require repeat procedural sedation and its associated risks. One study evaluating procedural sedation in patients with Anterior shoulder dislocations found that between 2.1% and 7.9% required repeat sedation after failed Reduction attempts [3]. By using ultrasound to check for reduction, physicians could perform multiple

attempts if needed without resedating the patient.

Despite the growing accessibility of bedside ultrasound, its use has not been previously described for verifying shoulder reduction [4]. A Medline search in November 2007 for articles published between 1950 and current using search terms shoulder reduction, shoulder dislocation and ultrasonography, shoulder dislocation and diagnostic imaging revealed no reported cases using bedside ultra- sound for this purpose.

In our experience, the posterior transverse approach with a 60-MHz probe described above in this case study is a quick and reliable way to examine the shoulder for

dislocation and successful reduction. This skill can be quickly learned and applied. It is painless for the patient and carries no risk of radiation. Images illustrating video loops and still images captured from the 2 cases described can be found at http://web.mmc.org/EmergencyMedicine/Ultrasound. Although ultrasound is understood to be a low-risk imaging modality, studies evaluating its sensitivity and specificity for verification of shoulder reduction after dislocation should be completed before recommendation of this technique. Similar studies to look at bedside ultrasound of other commonly dislocated joints may also prove useful.

Michael J. Halberg MD Timothy W. Sweeney MD William B. Owens MD

Department of Emergency Medicine

Maine Medical Center Portland, ME 04102, USA

E-mail address: [email protected] doi:10.1016/j.ajem.2008.05.023

References

1. Uehara D, Rudzinski J. Injuries to the shoulder complex and humerus. In: Tintinalli JE, editor. Emergency medicine. A comprehensive study guide. New York, NY: Mcgraw-Hill; 2004. p. 1697.
2. Riebel GD, McCabe JB. Anterior shoulder dislocation: a review of reduction techniques. Am J Emerg Med 1991;9(2):180-8.
3. Taylor DM, O’Brien D, Ritchie D, et al. Propofol versus midazolam/ fentanyl for reduction of anterior shoulder dislocation. Acad Emerg Med 2005;12:13-9.
4. Kendall J, Hoffenberg S, Smith S. History of emergency and critical care ultrasound; the evolution of a new imaging paradigm. Crit Care Med 2007;35(5):126-30.