Humeral avulsion of the glenohumeral ligament.

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W74 AJR:193, July 2009
Letters
AJR 2009; 193:W74–W75 0361–803X/09/1931–W74 © American Roentgen Ray Society
Humeral Avulsion of the
Glenohumeral Ligament
We read with great interest the informative
article by Melvin et al. [1], which provides
revealing insights into the lesion known as
humeral avulsion of the glenohumeral liga-
ment (HAGL). HAGL has been associated
with anterior shoulder instability and often
requires surgical repair [2, 3]. In their article,
Melvin et al. show four consecutive cases of
false-positive diagnoses of HAGL on MRI,
and surgical correlation was obtained in each
case. We add our experience with the HAGL
lesions and present three cases in which a
HAGL lesion was initially seen at MRI and
subsequently resolved on follow-up imaging.
The first patient, a 61-year-old woman,
presented with shoulder pain after trauma.
Initial radiographs revealed no bone abnor-
mality; however, further evaluation with
MRI of the shoulder revealed a HAGL lesion
(Fig. 1A). The patient declined surgical in-
tervention and opted to receive conservative
management. Repeat imaging 5 months later
showed resolution of the patient’s HAGL le-
sion (Fig. 1B).
The second patient, a 42-year-old man,
was injured in a fall. MR arthrography was
performed and revealed avulsion of the hu-
meral attachment of the glenohumeral liga-
ment (Fig. 2A). Follow-up 3 months later
with standard shoulder MRI confirmed that
the HAGL lesion had resolved (Fig. 2B)
without surgical intervention. This coincided
with resolution of the patient’s symptoms.
The third patient, a 20-year-old college
football player, sustained a shoulder injury
on the playing field. Initial investigation with
shoulder MRI also revealed a HAGL lesion
(Fig. 3A), and follow-up imaging with MR
arthrography after 8 weeks of intense reha-
bilitation showed resolution of the HAGL le-
sion (Fig. 3B).
These cases raise the question of whether
the initial diagnosis of a HAGL lesion was
incorrect or whether the HAGL lesion has
the potential to heal and thus resolve by the
time of any planned arthroscopy or interval
follow-up. Although our series unfortunate-
ly suffers from the lack of surgical correla-
tion, we do not fully agree with the conclu-
sions of Melvin et al. [1] that the diagnosis
of HAGL is best reserved for arthroscopy.
In our experience, the diagnostic features
of most HAGL lesions on MRI are char-
acteristic, with no differential diagnosis
usually offered, particularly in the setting
A
A
Fig. 1—61-year-old woman who presented with
shoulder pain after trauma.
A, T2-weighted fat-saturated MRI image shows
humeral avulsion of the glenohumeral ligament
(HAGL) lesion (arrow).
B, T2-weighted fat-saturated image obtained 5
months later shows resolution of HAGL lesion
(arrow). Surgery had not been performed.
Fig. 2—42-year-old man injured in fall.
A, T1-weighted image obtained after intraarticular
injection of gadolinium shows disruption of glenoid
attachment of glenohumeral ligament (arrow).
B, T2-weighted fat-saturation image obtained 3
months later shows resolution of humeral avulsion of
the glenohumeral ligament lesion (arrow).
B
B

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AJR:193, July 2009 W75
Letters
A
Fig. 3—20-year-old football player.
A, T2-weighted MR image shows humeral avulsion of
the glenohumeral ligament (HAGL) lesion (arrow).
B, MR arthrogram obtained 8 weeks after initial injury
shows resolution of HAGL lesion (arrow) after intense
rehabilitation but no surgery.
B
of a typical clinical history of instability.
Such lesions are confirmed at arthroscopy
in most instances; however, the possibil-
ity of an error by the radiologist in inter-
preting the image or of the existence of a
different underlying pathologic process
involving the inferior glenohumeral liga-
ment complex remains a possibility. Even
more likely, however, is that because the
inferior glenohumeral ligament is a compo-
nent of the shoulder capsule and given that
the shoulder capsule is a vascular structure,
the HAGL lesion may heal spontaneously in
the interim (as do other capsular structures
throughout the body). This should be kept
in mind at the time of interpretation and in
discussions with clinicians.
Darra T. Murphy
George C. Koulouris
Angela G. Gopez
Eoin C. Kavanagh
Mater Misericordiae University Hospital
Dublin, Ireland
DOI:10.2214/AJR.08.2228
WEB—This is a Web exclusive article.
References
1. Melvin JS, Mackenzie JD, Nacke E, Sennett BJ,
Wells L. MRI of HAGL lesions: four arthroscopi-
cally confirmed cases of false-positive diagnosis.
AJR 2008; 191:730–734
2. Bui-Mansfield LT, Taylor DC, Uhorchak JM, Te-
nuta JJ. Humeral avulsions of the glenohumeral
ligament: imaging features and a review of the
literature. AJR 2002; 179:649–655
3. Chhabra A, Diduch DR, Anderson M. Ar-
throscopic repair of a posterior humeral avulsion
of the inferior glenohumeral ligament (HAGL) le-
sion. Arthroscopy 2004; 20[suppl 2]:73–76