Quadrilateral Space Syndrome: Difference between revisions
No edit summary |
No edit summary |
||
| Line 7: | Line 7: | ||
== Clinically Relevant Anatomy<br> == | == Clinically Relevant Anatomy<br> == | ||
[[File:Quad space.jpg|thumb|400x400px|Anatomy of the Quadrilateral Space ]] | [[File:Quad space.jpg|thumb|400x400px|Anatomy of the Quadrilateral Space ]] | ||
Quadrilateral space syndrome (QSS) refers to a rare condition in which neural and vascular structures are entrapped in the quadrilateral space. This space is created by the lateral head of the triceps, teres minor, teres major, and medial border of the humerus. Through this space passes the axillary nerve and the posterior circumflex humeral artery. Fibrous bands in this space are commonly though to be the cause of compression | Quadrilateral space syndrome (QSS) refers to a rare condition in which neural and vascular structures are entrapped in the quadrilateral space. This space is created by the lateral head of the triceps, teres minor, teres major, and medial border of the humerus. Through this space passes the axillary nerve and the posterior circumflex humeral artery. Fibrous bands in this space are commonly though to be the cause of compression. One study showed that 14 of 16 cadavers had fibrous bands present, usually between the long head of the triceps and the teres major.<ref>McClelland D, Paxinos A. The anatomy of the quadrilateral space with reference to quadrilateral space syndrome [Internet]. Journal of Shoulder and Elbow Surgery. Mosby; 2007 [cited 2021Nov16]. Available from: <nowiki>https://www.sciencedirect.com/science/article/abs/pii/S1058274607005009</nowiki></ref> | ||
<br> | <br> | ||
== Mechanism of Injury / Pathological Process<br> == | == Mechanism of Injury / Pathological Process<br> == | ||
The exact mechanism and cause of the injury is still unclear at this time. However, it is often associated with overhead athletes such as pitchers, swimmers, or volleyball players causing repetitive trauma in the position of abduction and external rotation. Because of this, the dominant shoulder is most often affected, and the syndrome is reported to be most common in active people age 20-40.<ref name=":0" /> Others have hypothesized that anatomic variations such as a smaller quadrilateral space (QS), or even a glenoid cyst or paralabral cyst from a labrum injury could cause impingement of the QS. <ref>Hoskins WT. Case report quadrilateral space syndrome: A case study and ... [Internet]. British Journal of Sports Medicine . 2005 [cited 2021Nov17]. Available from: <nowiki>https://bjsm.bmj.com/content/bjsports/39/2/e9.full.pdf</nowiki></ref><br> | |||
== Clinical Presentation == | == Clinical Presentation == | ||
Patients generally present with an insidious onset of diffuse shoulder pain, posterior shoulder pain, weakness, and sensation loss in the distribution of the axillary nerve. Weakness is most notable in abduction and external rotation. It's possible to have atrophy in the external rotators or more noticeably in the deltoid if the case in chronic. Patients are almost always point tender at the QS itself. <ref name=":0" /><br> | |||
== Diagnostic Procedures == | == Diagnostic Procedures == | ||
Selective atrophy of the teres minor muscle can be identified by MRI, which is a positive indicator of the syndrome.<ref>Linker CS, Roy EA, Eliahou R, Linda DD, Gaskin CM, Rutten MJCM, et al. Quadrilateral space syndrome: Findings at Mr Imaging. [Internet]. Radiology. 1993 [cited 2021Nov16]. Available from: <nowiki>https://pubs.rsna.org/doi/abs/10.1148/radiology.188.3.8351331</nowiki></ref> However, MRI studies have shows that teres minor atrophy is a common finding in rotator cuff pathology, prior surgical intervention, and traction injuries with glenohumeral instability. <ref>Lindsay F. Quadrilateral space syndrome: a review. Journal of Shoulder and Elbow Surgery [Internet]. 2018 [cited 2021Nov16]; Available from: <nowiki>http://bonefix.co.nz/portals/160/images/Flynn%20Quadrangular%20space%20syndrome.pdf</nowiki></ref> | Selective atrophy of the teres minor muscle can be identified by MRI, which is a positive indicator of the syndrome.<ref>Linker CS, Roy EA, Eliahou R, Linda DD, Gaskin CM, Rutten MJCM, et al. Quadrilateral space syndrome: Findings at Mr Imaging. [Internet]. Radiology. 1993 [cited 2021Nov16]. Available from: <nowiki>https://pubs.rsna.org/doi/abs/10.1148/radiology.188.3.8351331</nowiki></ref> However, MRI studies have shows that teres minor atrophy is a common finding in rotator cuff pathology, prior surgical intervention, and traction injuries with glenohumeral instability. It's also been suggested that a lidocaine block in the area of the QS and axillary nerve can be a positive diagnostic criteria if the pain is abolished. <ref name=":0">Lindsay F. Quadrilateral space syndrome: a review. Journal of Shoulder and Elbow Surgery [Internet]. 2018 [cited 2021Nov16]; Available from: <nowiki>http://bonefix.co.nz/portals/160/images/Flynn%20Quadrangular%20space%20syndrome.pdf</nowiki></ref> | ||
== Outcome Measures == | == Outcome Measures == | ||
There is currently no specific outcome measure for QSS that is supported by evidence. Any shoulder outcome measure that takes into account functional use and overhead activities should be able to measure progress with QSS effectively. | |||
== Management / Interventions<br> == | == Management / Interventions<br> == | ||
| Line 34: | Line 33: | ||
== Differential Diagnosis<br> == | == Differential Diagnosis<br> == | ||
* Thoracic Outlet Syndrome | * [[Thoracic Outlet Syndrome (TOS)|Thoracic Outlet Syndrome]] | ||
* Cervical Radiculopathy | * [[Cervical Radiculopathy]] | ||
* Rotator Cuff Pathology | * Rotator Cuff Pathology | ||
* Internal/Posterior Shoulder Impingement | * Internal/Posterior Shoulder Impingement | ||
Revision as of 01:30, 18 November 2021
Clinically Relevant Anatomy
[edit | edit source]
Quadrilateral space syndrome (QSS) refers to a rare condition in which neural and vascular structures are entrapped in the quadrilateral space. This space is created by the lateral head of the triceps, teres minor, teres major, and medial border of the humerus. Through this space passes the axillary nerve and the posterior circumflex humeral artery. Fibrous bands in this space are commonly though to be the cause of compression. One study showed that 14 of 16 cadavers had fibrous bands present, usually between the long head of the triceps and the teres major.[1]
Mechanism of Injury / Pathological Process
[edit | edit source]
The exact mechanism and cause of the injury is still unclear at this time. However, it is often associated with overhead athletes such as pitchers, swimmers, or volleyball players causing repetitive trauma in the position of abduction and external rotation. Because of this, the dominant shoulder is most often affected, and the syndrome is reported to be most common in active people age 20-40.[2] Others have hypothesized that anatomic variations such as a smaller quadrilateral space (QS), or even a glenoid cyst or paralabral cyst from a labrum injury could cause impingement of the QS. [3]
Clinical Presentation[edit | edit source]
Patients generally present with an insidious onset of diffuse shoulder pain, posterior shoulder pain, weakness, and sensation loss in the distribution of the axillary nerve. Weakness is most notable in abduction and external rotation. It's possible to have atrophy in the external rotators or more noticeably in the deltoid if the case in chronic. Patients are almost always point tender at the QS itself. [2]
Diagnostic Procedures[edit | edit source]
Selective atrophy of the teres minor muscle can be identified by MRI, which is a positive indicator of the syndrome.[4] However, MRI studies have shows that teres minor atrophy is a common finding in rotator cuff pathology, prior surgical intervention, and traction injuries with glenohumeral instability. It's also been suggested that a lidocaine block in the area of the QS and axillary nerve can be a positive diagnostic criteria if the pain is abolished. [2]
Outcome Measures[edit | edit source]
There is currently no specific outcome measure for QSS that is supported by evidence. Any shoulder outcome measure that takes into account functional use and overhead activities should be able to measure progress with QSS effectively.
Management / Interventions
[edit | edit source]
add text here relating to management approaches to the condition
Differential Diagnosis
[edit | edit source]
- Thoracic Outlet Syndrome
- Cervical Radiculopathy
- Rotator Cuff Pathology
- Internal/Posterior Shoulder Impingement
- Glenohumeral Instability
- Suprascapular Nerve Injury
- Brachial Plexus Injury
Resources
[edit | edit source]
add appropriate resources here
References[edit | edit source]
- ↑ McClelland D, Paxinos A. The anatomy of the quadrilateral space with reference to quadrilateral space syndrome [Internet]. Journal of Shoulder and Elbow Surgery. Mosby; 2007 [cited 2021Nov16]. Available from: https://www.sciencedirect.com/science/article/abs/pii/S1058274607005009
- ↑ 2.0 2.1 2.2 Lindsay F. Quadrilateral space syndrome: a review. Journal of Shoulder and Elbow Surgery [Internet]. 2018 [cited 2021Nov16]; Available from: http://bonefix.co.nz/portals/160/images/Flynn%20Quadrangular%20space%20syndrome.pdf
- ↑ Hoskins WT. Case report quadrilateral space syndrome: A case study and ... [Internet]. British Journal of Sports Medicine . 2005 [cited 2021Nov17]. Available from: https://bjsm.bmj.com/content/bjsports/39/2/e9.full.pdf
- ↑ Linker CS, Roy EA, Eliahou R, Linda DD, Gaskin CM, Rutten MJCM, et al. Quadrilateral space syndrome: Findings at Mr Imaging. [Internet]. Radiology. 1993 [cited 2021Nov16]. Available from: https://pubs.rsna.org/doi/abs/10.1148/radiology.188.3.8351331
