A 19-year-old male presented to the orthopaedic surgeon with complaints of recurrent left shoulder pain. The patient practices combat sports and associates the complaints with a recent fall during training. A shoulder magnetic resonance imaging (MRI) was conducted, followed by MRI arthrography (MRA) due to inconsistent findings.
MRI revealed oedematous changes in the inferior glenohumeral joint capsule, with increased signal intensity on the fat-saturated proton-density (PDFS) sequence, suggestive of an inferior glenohumeral ligament (IGHL) lesion (Figures 1a, 1b, and 1c). Additionally, there was an increased signal intensity in the superior labrum, which may indicate a labral lesion. However, this finding was considered non-specific due to the absence of intra-articular fluid or contrast (Figure 1a).
Subsequent MRA revealed an intrasubstance full-thickness rupture of the anterior band of the IGHL with contrast extravasation (Figures 2a and 2b). This finding was not documented on the previous conventional MRI, which only indicated capsular oedema. Additionally, the axillary pouch changed from its normal U-shape to a J-shape on fat-saturated T2-weighted sequences (Figures 3a and 3b), indicating IGHL laxity and loss of its stabilising function. MRA also identified a superior labrum from anterior to posterior (SLAP) lesion (Figures 2c, 2d, and 3c), which was not clearly visible on MRI due to lack of fluid joint distention.
Background
Humeral avulsion of glenohumeral ligament (HAGL) injuries are an uncommon cause of shoulder instability characterised by disruption of IGHL, predominantly documented in young athlete male patients [1,2].
Clinical Perspective
The IGHL complex comprises an anterior and posterior band with an interposed axillary pouch. Its primary function is to restrain anterior and posterior translation of the humeral head [1,2]. HAGL lesions can be categorised according to the involvement of the anterior or posterior band and the presence or absence of bony avulsion [2]. Anterior band involvement is more common, with a reported frequency of 93% [2]. The IGHL lesion may occur at three anatomical sites: glenoid insertion (40%), intrasubstance (35%), and humeral neck insertion (25%) [1,2]. In our case, the patient had an anterior full-thickness intrasubstance HAGL lesion of the IGHL, without bony avulsion.
Imaging Perspective
Typical MRI features of HAGL injuries include an increased signal intensity and thickening of the IGHL and inferior capsule, contrast extravasation or joint effusion along the humeral neck, and a distinctive J-shaped axillary pouch (“J” sign) due to the avulsion of the IGHL [1,2,4]. Additionally, many HAGL cases are associated with humeral head osteochondral lesions, labral injuries, and rotator cuff lesions, with the subscapularis tendon being the most commonly affected structure [1,2,4].
Although arthroscopy remains the method of choice for assessing shoulder instability, MRI is essential to guide both arthroscopic and preoperative evaluation of shoulder instability. These injuries are often challenging to diagnose and, without a high index of clinical suspicion, can be easily overlooked [2,3].
In our case, conventional MRI detected oedematous changes suggestive of IGHL injury, but the capsuloligamentous tear was only confirmed after distension of the joint capsule with contrast material. These findings align with the literature, indicating that MRA could increase sensitivity in detecting labroligamentous injuries of the glenohumeral joint, including HAGL injuries, when compared to conventional MRI alone [3,5]. Additionally, fat-saturated T1-weighted abduction external rotation MRI sequence (ABER) can help in detecting anterior and posterior labral tears, especially when routine MRI axial images do not clearly identify a lesion [5].
Outcome
The patient underwent arthroscopy and surgery, which confirmed an IGHL tear that was repaired. The SLAP lesion and an anteroinferior Bankart lesion were also identified and repaired with tenotomy of the long head of the biceps tendon and labrum fixation.
Take Home Message
In conclusion, this case emphasises the valuable contribution of MR arthrography imaging to diagnostic approaches in assessing shoulder instability.
All patient data have been completely anonymised throughout the entire manuscript and related files.
Humeral avulsion of glenohumeral ligament (HALG injury) with superior labrum from anterior to posterior (SLAP) lesion
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Based on the provided MRI and MRA images of the shoulder joint, the following characteristic changes are observed:
Considering the patient’s young age, involvement in contact sports, recent history of trauma, and imaging findings suggesting involvement of the IGHL, the following diagnoses or differentials are considered:
Considering the patient’s clinical symptoms (recurrent shoulder pain, history of trauma), the imaging features (IGHL avulsion on the humeral side, a distinct “J” sign), and subsequent arthroscopic findings indicating soft tissue tear, the most likely final diagnosis is: Humeral Avulsion of the Glenohumeral Ligament (HAGL) combined with SLAP lesion and Bankart injury.
After surgery or conservative treatment, phased rehabilitation exercises for the shoulder joint should be implemented, following a gradual progression based on the FITT-VP principle:
If the patient has fragile bones, cartilage defects, or other systemic conditions, extra caution should be taken to avoid high-impact movements. Regular follow-up is advised, including imaging if necessary.
Disclaimer: This report is solely based on the provided images and clinical information for reference and does not replace in-person diagnosis or professional medical advice. Please consult an orthopedic specialist or other relevant healthcare professionals for specific treatment plans.
Humeral avulsion of glenohumeral ligament (HALG injury) with superior labrum from anterior to posterior (SLAP) lesion
