|
|
TEACHING IMAGES |
|
Year : 2019 | Volume
: 7
| Issue : 1 | Page : 129-130 |
|
Spinoglenoid ganglion cyst mimicking rotator cuff tear
Reddy Ravikanth, Kanagasabai Kamalasekar
Department of Radiology, Holy Family Hospital, Thodupuzha, Kerala, India
Date of Web Publication | 12-Jun-2019 |
Correspondence Address: Dr. Reddy Ravikanth Department of Radiology, Holy Family Hospital, Thodupuzha - 685 605, Kerala India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/amhs.amhs_4_19
Spinoglenoid notch ganglion cyst is a rare lesion located to the dorsum of glenohumeral joint, leading to entrapment of the suprascapular nerve causing infraspinatus atrophy. Other described features include weakness with external rotation and posterior shoulder tenderness. Here, we report a case of 34-year-old gentleman with vague shoulder pain exacerbated by overhead activities. MRI in patients with non-specific shoulder pain now makes earlier detection possible of lesions which may mimic rotator cuff tears.
Keywords: Ganglion cyst, spinoglenoid notch, suprascapular nerve entrapment
How to cite this article: Ravikanth R, Kamalasekar K. Spinoglenoid ganglion cyst mimicking rotator cuff tear. Arch Med Health Sci 2019;7:129-30 |
Description | |  |
A 34-year-old gentleman presented with vague shoulder pain of several months to the orthopedics department which was exacerbated by overhead activities. Muscle weakness in abduction and external rotation and chronic pain in the dorsal region of the shoulder were the clinical symptoms. On physical examination, the patient demonstrated full shoulder range of motion with no painful movements. We suspected rotator cuff tear or tendonitis and hence treated the patient with physiotherapy and analgesics, but he showed no improvement. Magnetic resonance imaging (MRI) of the shoulder revealed spinoglenoid notch ganglion cyst and high-signal intensity in the infraspinatus muscle on fluid-sensitive sequences [Figure 1] and [Figure 2]. Subsequent shoulder arthroscopy revealed no labral pathology. Owing to the large cyst size, open decompression was done. Postoperatively, the patient showed resolution of symptoms over 2 months. | Figure 1: Spinoglenoid notch ganglion. Coronal oblique proton-density fat saturation magnetic resonance image demonstrating abnormal signal intensity involving the infraspinatus muscle
Click here to view |
 | Figure 2: Spinoglenoid notch ganglion. Axial proton-density fat saturation magnetic resonance image demonstrating a multiloculated cyst extending through the spinoglenoid notch
Click here to view |
Questions | |  |
Q1: Spinoglenoid ganglion cyst causes atrophy of which muscle?
Q2: What is the age group commonly affected?
Q3: How is muscle denervation identified on MRI?
Q4: What are the available treatment options?
Answers | |  |
A1: Spinoglenoid notch ganglion cyst is a rare lesion located to the dorsum of glenohumeral joint leading to entrapment of the suprascapular nerve, thus causing isolated atrophy of infraspinatus muscle.
A2: The ganglion cyst affects dominant arm shoulders of young men.
A3: On MRI, diffuse hyperintense-signal intensity in the affected muscle with or without muscle atrophy is the result of muscle denervation. Signal intensity returns to normal with recovery of motor function of the muscle involved.
A4: Percutaneous aspiration of the ganglion cyst by means of ultrasonography (USG) or computed tomography (CT), arthroscopic decompression of the ganglion, and open excision of the cyst are the available surgical options.
Discussion | |  |
Spinoglenoid notch ganglion cyst is a rare lesion located to the dorsum of glenohumeral joint, leading to entrapment of the suprascapular nerve. In 1981, Ganshorn first reported suprascapular nerve entrapment at the level of the spinoglenoid notch with associated infraspinatus muscular atrophy.[1] Suprascapular nerve entrapment presents with posterior shoulder pain and usually affects physically active men in young- to middle-aged group.[2] Incidentally detected paralabral cysts on MRI do not result in compression neuropathies. Denervation changes with atrophy of both supraspinatus and infraspinatus muscles are the results of ganglia extending into the suprascapular notch, while isolated atrophy of the infraspinatus muscle is the result of spinoglenoid notch ganglion cysts.[3] Large cysts (mean diameter of 3.1 cm) located adjacent to the posterior or inferior labrum lead to compression neuropathy.[4] On MRI, muscle denervation shows hyperintense-signal changes in affected muscle with or without muscle atrophy. Signal intensity returns to normal with recovery of motor function. Percutaneous aspiration of the ganglion cyst by means of USG or CT, arthroscopic decompression of the ganglion, and open excision of the cyst are the available surgical options.
Take home message
In our case, the spinoglenoid ganglion straddled the base of the spine of the scapula, extending into infraspinatus fossa causing infraspinatus atrophy. The nerve to infraspinatus was either compressed against the spine or stretched over the posterior aspect of the ganglion. The differential diagnosis in the case of shoulder pain includes rotator cuff tears and quadrilateral space syndrome.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References | |  |
1. | Martinoli C, Bianchi S, Pugliese F, Bacigalupo L, Gauglio C, Valle M, et al. Sonography of entrapment neuropathies in the upper limb (wrist excluded). J Clin Ultrasound 2004;32:438-50. |
2. | Piatt BE, Hawkins RJ, Fritz RC, Ho CP, Wolf E, Schickendantz M, et al. Clinical evaluation and treatment of spinoglenoid notch ganglion cysts. J Shoulder Elbow Surg 2002;11:600-4. |
3. | Carroll KW, Helms CA, Otte MT, Moellken SM, Fritz R. Enlarged spinoglenoid notch veins causing suprascapular nerve compression. Skeletal Radiol 2003;32:72-7. |
4. | Davidge CM, Walker R, Brett K, Boorman RS. Spontaneous resolution of a spinoglenoid notch cyst and associated suprascapular nerve palsy: A case report. J Shoulder Elbow Surg 2007;16:e4-7. |
[Figure 1], [Figure 2]
|