Article, Radiology

Point-of-care ultrasonography for the management of shoulder dislocation in ED

a b s t r a c t

Objective: Point-of-care ultrasonography (POCUS) is an easily available and Noninvasive tool without radiation exposure.that is also gaining a broad range of use in emergency departments. The aim of this study is to evaluate the value of POCUS in the diagnosis of Shoulder dislocation by comparing with Plain radiography.

Methods: This prospective observational study with a convenience sampling was conducted in emergency de- partments of 2 hospitals. Patients older than 15 years with possible shoulder dislocation during the physical ex- amination composed the study population. All the study patients underwent POCUS evaluation to detect a shoulder dislocation or fracture before radiography, and the POCUS procedure was also achieved after the reduc- tion attempt.

Results: A total of 103 patients were enrolled in the study. The mean age of study subjects was 33.9 +- 15 years, and 80.6% (n = 83) of them were male. The sensitivity and specificity of POCUS in identifying dislocation were 100% (95% confidence interval [CI], 96%-100%) and 100% (95% CI, 48%-100%), respectively. POCUS also confirmed reduction in 93 of 94 patients with a specificity of 100% (95% CI, 96%-100%). POCUS has a sensitivity of 100% (95% CI, 63%-100%) for excluding a shoulder fracture but a specificity of 84.2% (95% CI, 75%-91%).

Conclusion: Point-of-care ultrasonography is an effective tool to either rule in or rule out shoulder dislocation in the emergency setting. Furthermore, it is a robust sensitive tool for excluding fractures but with false- positive results.

(C) 2016

  1. Introduction

The shoulder (Glenohumeral joint) is a dynamic articulation that possesses a wide range of motion, which may also lead the joint leaning to dislocations. Therefore, nearly half of the dislocations of large joints consist of Shoulder dislocations [1]. Most dislocations of shoulder are to anterior region (95%), secondly to posterior (2%-5%), and rarely to

? Contributorship: collected data: Can Akyol, Faruk Gungor, Angelika Janitzky Akyol, Mustafa Kesapli, Ramazan Guven, Umut Cengiz, Halil Ibrahim Toksul; served as scientific advisor: Eken C; statistical study: Eken C; writing the article: Eken C.

?? Funding: This research received no specific funding.

??? Competing interests: There are no competing interests

* Corresponding author at: Emergency Medicine, Akdeniz University Hospital, Depart- ment of Emergency Medicine, Antalya, Turkey.

E-mail addresses: [email protected] (C. Akyol), [email protected] (F. Gungor), [email protected] (A.J. Akyol), [email protected] (M. Kesapli), [email protected] (R. Guven), [email protected] (U. Cengiz),

[email protected] (H.I. Toksul), [email protected], [email protected] (C. Eken).

inferior part of the shoulder. Plain radiography has been the most com- mon tool for diagnosing shoulder dislocation and to evaluate the suc- cess of reduction. However, case reports and studies reported that point-of-care ultrasonography might be an accurate tool in di- agnosing shoulder dislocation as well as plain radiography [2-4].

POCUS is an easily available and noninvasive tool without radiation exposure. Meanwhile, Ultrasonographic evaluation of shoulder is easy to learn because of the existence of strict anatomical landmarks such as tuberculum majus and minus, humeral head, coracoid process, scap- ula, and glenoid.

The aim of this study is to evaluate the value of POCUS in the diagno- sis of shoulder dislocation by comparing with plain radiography.

  1. Material and methods
    1. Study design

This prospective observational study with a convenience sample was conducted between January 2015 and August 2015. The study was conducted in the emergency departments (EDs) of 2 hospitals,

http://dx.doi.org/10.1016/j.ajem.2016.02.006

0735-6757/(C) 2016

one of which is an academic department. The annual census of the 2 hospitals is 400,000. The local ethical committee approved the study, and written inform consent was obtained from all the study patients. The clinicaltrial.gov ID is NCT02469818.

Selection of participants

Patients older than 15 years with a possible shoulder dislocation during the physical examination composed the study population. Pa- tients were enrolled in the study during the shifts that the attending physicians trained for the study were working. All the study patients underwent POCUS evaluation to detect shoulder dislocation or fracture before radiograph, and the defined POCUS procedure was also achieved after the reduction attempt.

Patients younger than 15 years old, with multiple trauma or unstable vital signs, who denied to give inform consent, who were diagnosed to have any fracture before the POCUS, and with open fracture or disloca- tion were excluded from the study.

Patients who were diagnosed to have any kind of fracture after the initial POCUS were referred for orthopedic consultation, and patients in whom the reduction was not accomplished were excluded from the postreduction POCUS evaluation process.

  1. Methods of measurement
    1. Ultrasonography devices

Two kinds of ultrasonography (USG) devices were used for the study: a standard USG device (ESAOTE/Firenze/ITALIA) and a portable USG device (Mindray M5, China). A 7.5-MHz linear transducer was used for all evaluations. The academic ED has both devices, and the other one has only the ESAOTE device. Mindray is a portable USG used particularly for patients who needed sedation.

Table 1

Evaluation steps of shoulder dislocation by POCUS

Step 1. View the humeral shaft by placing the transducer to the midsuperior part of the humerus at the posterolateral region (Fig. 1A and B).

Step 2: Slowly slide the transducer to the upward to view the humeral head (Fig. 2A and B)

Step 3: Slide the transducer to the posterior part of the shoulder to view the glenohumeral joint and posterior glenoid labrum (Fig. 3A and B). The transducer should be slided toward the right and left if the view could not be achieved.

Humeral head is posteriorly located when compared with glenoid in normal shoulder and has a slightly upper view compared with glenoid (Figs. 3B and 5A).

Step 4: Evaluate the humeral head, tuberositas major and minor, and intertubercular groove by sliding the transducer to the anterior at the screening area of humerus and glenoid (Fig. 4A and B).

Humeral neck and tuberculum majus and minus were scanned from the anterior and pos- terior locations where the glenoid rim and shoulder head are best viewed.

*LT: lesser tuberculum, **GT: greater tuberculum.

POCUS training

A total of 8 attending physician were trained for shoulder POCUS by a USG trainer. The POCUS screeners had a median experience time of

7.5 years (min-max, 2-15 years). The POCUS training was composed of 2 parts: a 30-minute lecture and a 2-hour practicing part. The training included the shoulder anatomy; diagnosing the shoulder dislocation and also its position; and detecting a fracture in tuberculum majus- minus, humeral head, and neck and glenoid rim. The POCUS screeners rated the patient as possessing the pathology or not. However, if they are not sure on the diagnosis, it was rated as a suspected pathology.

Patient and probe position

The patient was in a sitting position, and the physician remained beside the shoulder to be examined. Both the US transducer and screen marker were adjusted to be at the left side. At this stage, upper part of the screen rep- resents the posterior and the lower part of the screen represents the anterior.

Figs. 1-4. Steps of performing a POCUS on shoulder; also defined in detail in Table 1.

Image of Fig. 5

Fig. 5. Anterior (B) and posterior (C) glenohumeral dislocation and a postreduction view of the same patient with anterior dislocation (A). *PGL: posterior glenoid labrum.

Figs. 1-4 show the steps of performing a POCUS on the shoulder, de-

fined in detail in Table 1.

Fig. 5B displays an anterior glenohumeral dislocation (GHD) diag- nosed by viewing the humeral head at the lower side of glenoid. If ex- tremely located to posterior, a diagnosis of posterior GHD was achieved by comparing the opposite shoulder (Fig. 5C). If the shoulder was not dislocated, the patient should be able to internally and external- ly rotate the shoulder while adducted, and the rotational articulation between the humeral head and glenoid fossa will be seen clearly on the USG screen. Fig. 5-1 also displays postreduction view the same pa- tient with anterior GHD.

Fig. 6 displays the POCUS views of normal humeral head and various types of fractures in shoulder.

Outcome measures

The primary outcome of the study was to determine the diagnostic accuracy of POCUS for diagnosing shoulder dislocations. The secondary outcomes were the ability of POCUS to verify the shoulder reduction and also diagnose the fractures.

Statistical analysis

The study data were analyzed in MedCalc and SPSS software. The numeric variables are presented as mean +- standard deviation and me- dian (minimum-maximum), and frequent data as rates. The diagnostic utility of USG is expressed by sensitivity and specificity. The 95% confi- dence interval (CI) was also used to express the certainty limits.

  1. Results

A total of 103 patients presumed to have shoulder dislocation were enrolled in the study. Baseline features, reduction techniques, and de- tails of sedation analgesia are displayed in Table 2. The mean age of study subjects was 33.9 +- 15 years, and 80.6% (n = 83) of them were

male. The most common mechanisms of the shoulder dislocation were falls (35%, n = 36) and arm motion (31.1%, n = 32).

POCUS diagnosed 98 patients with dislocation and 5 patients as nor- mal, which were also confirmed by radiograph. The sensitivity and spec- ificity of POCUS in identifying dislocation were 100% (95% CI, 96%-100%) and 100% (95% CI, 48%-100%), respectively. However, POCUS provided a diagnosis of 80 patients as not having a fracture, 5 patients with a frac- ture, and 15 patients with a suspected fracture. Although there were no false-positive or -negative patients in the 85, only 3 of the 15 suspected patients had a fracture which was confirmed by radiograph. So, POCUS has a sensitivity of 100% (95% CI, 63%-100%) for excluding a shoulder fracture but a specificity of 84.2% (95% CI, 75%-91%) (Table 2). POCUS also confirmed reduction in 93 of 94 patients with a specificity of 100% (95% CI, 96%-100%). Table 3 displays the success of POCUS in diag- nosing the dislocations and fractures. Three patients were admitted to the orthopedics ward and 1 patient to chest surgery, and those also did not have a postreduction view.

  1. Discussion

This study showed that POCUS might be an effective tool in diagnos- ing shoulder dislocation. Plain radiographies have been the standard di- agnostic tool at the management of patients presumed to have a shoulder dislocation. Pre- and postreduction radiographies are the pro- cedures commonly used for many years. However, there are also ap- proaches supporting the use of a postreduction imaging alone which is based on the remarks that the physical examination and history might be adequate for an experienced physician to diagnose a shoulder dislocation. Shuster et al [5] reported that prereduction imaging does not alter the management but also leads to delays in treatment. Shuster et al [6] also showed that physicians are able to diagnose 82.5% of these patients accurately if they obey the guidelines and exclude prereduction imaging in 88.9% of patients. Furthermore, another study indicates that the prereduction diagnosing may have minimal utility in the second and

Image of Fig. 6

Fig. 6. POCUS view of a normal humeral head and various types of fractures in shoulder. A normal humeral head, Hill-Sachs deformity, fracture of tuberculum majus, and a Bankart fracture are displayed in alphabetical order.

Table 2

Demographic features, procedural sedation, and reduction maneuvers used in study patients

Variable n (%)

Age (y), mean +- SD 33.9 +- 15

Sex (male) 83 (80.6)

Mechanism

Sleeping

8 (7.8)

Arm motion

32 (31.1)

Fall down

60 (58.3)

Vehicle accident

1 (1)

Motorcycle accident

5 (4.9)

Seizure

2 (1.9)

Swimming

11 (10.7)

Other sports

8 (7.8)

Frequency of dislocation

1

65 (63.1)

2

20 (19.4)

3

9 (8.7)

4

5 (4.9)

5

4 (3.9)

Drugs for PSA

No PSA

42 (40.8)

Propofol

48 (46.6)

Midazolam + fentanyl

3 (2.8)

Ketamine

Reduction maneuver

1 (1)

External rotation

83 (80.6)

Scapular manipulation

8 (7.8)

Other

3 (2.9)

Fracture and dislocation No pathology

5 (4.9)

Dislocation without fracture 90 (87.4)

Dislocation with fracture 8 (7.8)

Types of fracturesa

Tuberculum majus 2 (25)

Humeral neck 2 (25)

Hill-Sacks deformity 4 (50)

Bankart fracture 1a

Abbreviation: PSA: procedural sedation analgesia.

a One patient had both Hill-Sacks deformity and Bankart fracture.

third decades because of the rare incidence (1%) of shoulder disloca- tions [7].

The study by Kahn and Mehta [8] showed that postreduction radio- graphs might be more beneficial.

Neither patients nor physicians realize the existence of shoulder re-

duction, and in some cases, traumas secondary to relocation that differ according to the Reduction method may be a concern. So, postreduction radiographs are being used routinely for these concerns. Scapula Y ra- diographs are sometimes used in the presence of doubt in diagnosis and treatment, leading to much more radiation exposure.

POCUS has been used more commonly for either fractures or dislocations in the last years [9]. Nonexistence of radiograph and practical use at bedside also allow POCUS to be an easily repeatable tool and also a common diagnostic tool particularly in simple fractures and dislocations [10].

Furthermore, there are studies reporting the POCUS to be as valuable at least as radiographs and to accelerate the treatment process and di- minish the errors. Blakeley et al [11] claimed that POCUS can show the

dislocation and relocations and also pick out the anterior-posterior confusion based on 5 cases. Although they did not purport to replace radiograph by POCUS completely, this may be reasonable for patients having reduction under sedation. This is remarkable point because postreduction radiograph should not be postponed for an awake patient because of the possible requirements for additional attempts [3,11].

Posterior GHDs are more challenging compared with anterior, and the misdiagnosis rate is 50% initially [12]. Shoulder contusion, rotator cuff injuries, and accompanying fractures are challenges for the diagnosis [13].

The light bulb sign in anterior-posterior radiographs is seen rarely [14]. Although computerized tomography provides precise diagnosis, more radiographs and wasting time are the challenges. Some case re- ports and the study by Abbasi et al showed that the diagnosis and treat- ment of posterior shoulder dislocation can be performed by POCUS [2-4]. Yuen et al [3] showed that the POCUS for anterior shoulder eval- uation could also be performed for posterior. Yuen et al reported 2 cases of acute posterior shoulder dislocation confirmed by bedside USG scan. They concluded that bedside USG for diagnosis of posterior shoulder dislocation was accurate, noninvasive, repeatable, convenient, and without ionizing radiation.

Similarly, Halberg et al [4] presented 2 cases of anterior and posteri- or shoulder dislocations for which the success of the reduction process was confirmed correctly with USG.

Abbasi et al [2], the biggest study so far, reported that POCUS is 100%

sensitive and specific for shoulder dislocation and may provide a more rapid management compared with radiography. The present study also showed that POCUS is 100% sensitive and specific for prereduction diag- nosis and also 100% specific for postreduction. These findings are re- markable for the management of these patients particularly in crowded EDs. In addition, avoiding the radiation exposure is also pleasing.

  1. Limitations

There are several limitations to this study. The study consists of a convenience sample of patients that were only recruited to the study during the shifts of POCUS screeners. There were only 5 patients with no shoulder dislocation. But this is an inevitable result that most of the patients who presented with a suspicious shoulder dislocation have generally been verified ultimately during the daily practice. Another limitation to the present study is the 2 different types of US models used for the study. There were only 8 screeners for the study, and they had an extensive prior experience. However, there is a wide range of physicians using POCUS with various levels of experience, leading to a more heterogeneous group of POCUS providers than the present study. There were also 4 patients excluded from the postreduction anal- ysis because they were admitted to the hospital.

  1. Conclusion

Point-of-care USG is an effective tool to either rule in or rule out shoulder dislocation in the emergency setting. Furthermore, it is a ro- bust sensitive tool for excluding fractures but with false-positive results.

Table 3

Performance of POCUS in diagnosing a shoulder dislocation and confirmation of reduction

USG finding Shoulder dislocation detection Shoulder reduction confirmation

Radiograph results

Radiograph results

Positive

Negative

Total

Positive (reduction succeeded)

Negative (reduction failed)

Total

Positive

98

0

98

93

1

94

Negative

0

5

5

0

0

0

Total

98

5

103

93

1

94

References

  1. Zacchilli MA, Owens BD. Epidemiology of shoulder dislocations presenting to emer- gency departments In the United States. J Bone Joint Surg Am 2010;92:542-9. http:// dx.doi.org/10.2106/JBJS.I.00450.
  2. Abbasi S, Molaie H, Hafezimoghadam P, Zare MA, Abbasi M, Rezai M, et al. Diagnostic accuracy of ultrasonographic examination in the management of shoulder disloca- tion in the emergency department. Ann Emerg Med 2013;62:170-5. http://dx.doi. org/10.1016/j.annemergmed.2013.01.022.
  3. Yuen CK, Chung TS, Mok KL, Kan PG, Wong YT. Dynamic ultrasonographic sign for posterior shoulder dislocation. Emerg Radiol 2011;18:47-51. http://dx.doi.org/10. 1007/s10140-010-0906-7.
  4. Halberg MJ, Sweeney TW, Owens WB. Bedside ultrasound for verification of shoul- der reduction. Am J Emerg Med 2009;27:134.e5-6. http://dx.doi.org/10.1016/j. ajem.2008.05.023.
  5. Shuster M, Abu-Laban RB, Boyd J. Prereduction radiographs in clinically evident an- terior shoulder dislocation. Am J Emerg Med 1999;17:653-8.
  6. Shuster M, Abu-Laban RB, Boyd J, Gauthier C, Shepherd L, Turner C. Prospective eval- uation of a guideline for the selective elimination of pre-reduction radiographs in clinically obvious Anterior shoulder dislocation. CJEM 2002;4:257-62.
  7. Orloski J, Eskin B, Allegra PC, Allegra JR. Do all patients with shoulder dislocations need prereduction x-rays? Am J Emerg Med 2011;29:609-12. http://dx.doi.org/ 10.1016/j.ajem.2010.01.005.
  8. Kahn JH, Mehta SD. The role of post-reduction radiographs after shoulder dislocation. J Emerg Med 2007;33:169-73. http://dx.doi.org/10.1016/j.jemermed.2007.01.003.
  9. Saul T, Ng L, Lewiss RE. Point-of-care ultrasound in the diagnosis of upper extremity fracture-dislocation. A pictorial essay. Med Ultrason 2013;15:230-6.
  10. Joshi N, Lira A, Mehta N, Paladino L, Sinert R. Diagnostic accuracy of history, physical examination, and bedside ultrasound for diagnosis of extremity fractures in the emergency department: a systematic review. Acad Emerg Med 2013;20:1-15.
  11. Blakeley CJ, Spencer O, Newman-Saunders T, Hashemi K. A novel use of portable ul- trasound in the management of shoulder dislocation. Emerg Med J 2009;26:662-3. http://dx.doi.org/10.1136/emj.2008.069666.
  12. Kowalsky MS, Levine WN. Traumatic posterior glenohumeral dislocation: classifica- tion, pathoanatomy, diagnosis, and treatment. Orthop Clin North Am 2008;39: 519-33. http://dx.doi.org/10.1016/j.ocl.2008.05.008 [viii].
  13. Robinson CM, Aderinto J. Posterior shoulder dislocations and fracture-dislocations. J Bone Joint Surg Am 2005;87:639-50. http://dx.doi.org/10.2106/JBJS.D.02371.
  14. Mouzopoulos G. The “Mouzopoulos” sign: a radiographic sign of posterior shoulder dislo- cation. Emerg Radiol 2010;17:317-20. http://dx.doi.org/10.1007/s10140-010-0862-2.

Leave a Reply

Your email address will not be published. Required fields are marked *