Humeral Avulsion of the Glenohumeral Ligaments

Humeral Avulsion of the Glenohumeral Ligaments, abbreviatedHAGL, are a rare subtype of Glenoid Labrum Tears where the Avulsion Fracture is of the Glenohumeral Capsular Ligaments attachment on the Humerus rather than the Glenoid Labrum . There are several HAGL variations, each with distinct features (SOURCE-1+3):

  • Anterior HAGL- accounts for the majority (~55%) of HAGL Lesions and occurs when the Anterior Portion of the Inferior Glenohumeral Ligament is avulsed from the anatomical Neck of Humerus , leading to Anterior Glenohumeral Instability

  • Anterior Body HAGL (BHAGL)- a more severe form of the Anterior HAGL where a bony fragment of the Humerus is avulsed along with the Anterior portion of the Inferior Glenohumeral Ligament . Accounts for roughly 17% of HAGL Lesions

  • Floating Anterior IGHL- a complex injury that involves two seperate Avulsion Fractures that leave the Inferior Glenohumeral Ligament freely floating in the joint, leading to notable instability. Accounts for roughly 21% of HAGL Lesions:

  • Posterior HAGL- less common (~2%) posterior variation of the anterior HAGL where the Posterior portion of the Inferior Glenohumeral Ligament is avulsed from the posteroinferior aspect of the Humeral Neck

  • Posterior BHAGL- posterior equivalent of BHAGL where there is an Avulsion Fracture of the Posterior portion of the Inferior Glenohumeral Ligament which removes a fragment of Bone from the Humerus . This HAGL classification is very rare

  • Floating Posterior IGHL- a severe injury where the Posterior portion of the Inferior Glenohumeral Ligament avulses from both the Humerus and the Posteroinferior Labrum, leaving the ligament freely-floating within the joint. Accounts for roughly 4% of HAGL Lesions


Pathomechanics

HAGL Lesions are most often the result of high-energy trauma that causes Glenohumeral Joint Subluxation or Dislocation , with a smaller proportion attributed to the accumulation of micro-trauma from repetitive overhead movements (SOURCE-1+2+4). The precise nature of the tear is likely also afforded to the ligaments themselves. For example, the Posterior Band of the Inferior Glenohumeral Ligament is the weakest part of the capsuloligamentous complex, leaving it vulnerable to injury at its Humeral attachment (SOURCE-4). The primary mechanism for an Anterior HAGL Lesion is hyperabduction and GH Joint - External Rotation , whereas a Posterior HAGL is associated with Posterior Glenohumeral Dislocation (SOURCE-2+3+4).

While the location of the tear often corresponds to the direction of the trauma (e.g., a posterior HAGL is associated with posterior dislocation), the same cannot be said for the direction of instability. A significant number of patients (~50%) with a Posterior HAGL lesion also have a concurrent anterior capsular injury, a phenomenon that supports the "circle concept" of glenohumeral instability (SOURCE-3).

Prevalence

HAGL Lesions are reported to account for ~1.6% of patients experiencing Pain in The Shoulder Girdle (SOURCE-3). The overwhelming majoirty (~94%) of those with HAGL Lesions are males with an average age of 25-30 which is likely attributed to a higher participation in high-energy/ risk physical activities (SOURCE-3). HAGL Lesions are estimated to be present in 7.5-9.3% of primary Glenohumeral Dislocations and are also commonly seen in those over the age of 35 following an initial Dislocation (SOURCE-2).


Pathology

HAGL Lesions are complex injuries that rarely occur in isolation. The following pathologies are commonly associated with them, often serving as predisposing factors or occurring concomitantly:

Recurrent Glenohumeral Instability - HAGL Lesions are a under-recognised cause of recurrent instability to the extent that their misdiagnosis is believed to account for a notable portion of failed surgeries. 18% of anterior stabilisation surgeries for instability where found to have a HAGL lesion (SOURCE-3). Approximately 27% of those with instability in absence of a Bankart Lesion are reported to have a HAGL Lesion (SOURCE-3).

Glenohumeral Dislocation - or Subluxation represents the main avenue by which HAGL Lesions are formed with an estimated prevalence of 7.5-9.3% in primary Dislocations and 10% in recurrent anterior dislocations (SOURCE-2+3)

Neuropathy - concomitant nerve injury occurs in as many as 55% of HAGL Lesions, with the Axillary Nerve most often implicated as its course nears the 6 o’clock position on the Glenoid Labrum (SOURCE-2). Traumatic lesions that affect the inferior capsule, such as HAGL or GAGL lesions, are therefore more likely to implicate the Axillary Nerve (SOURCE-4)

Other Glenoid Labrum Tears - occur concomitantly with 25% of HAGL Lesions (SOURCE-3):

Rotator Cuff Tear - occur concomitantly with 23% of HAGL Lesions, the Subscapularis being the most frequently implicated (SOURCE-1+3)

Hill-Sachs Lesion - occur concomitantly with 17% of HAGL Lesions (SOURCE-1+3)


Assessment

HAGL Lesions are often difficult to diagnose which is thought to contribute to its low rates of reporting (SOURCE-1). Many methods of evaluation for HAGL Lesions lack specificity and sensitivity (SOURCE-1):

Observation

A HAGL Lesion if often associated with nonspecific (SOURCE-1):

  • Pain

  • Weakness

  • Dysfunction

These lesions should be suspected where there is recurrent Anterior Glenohumeral Instability in absence of a Bankart Lesion (SOURCE-1). Any signs of local Muscle atrophy may implicate the Brachial Plexus or other Peripheral Nerves (SOURCE-2).

Range of Motion

Range of Motion assessment may be a relevant diagnostic tool and post-surgical metric for those with HAGL Lesions. With Anterior HAGL lesions, compromise of the Anterior Band of the Inferior Glenohumeral Ligament would lead to excessive GH Joint - External Rotation and GH Joint - Abduction range. The size of the lesion, however, appears to determine the extent of laxity. On cadavers smaller lesions did not appear to exacerbate range of motion, while larger HAGL lesions increased both range of motion and translation of the Head of Humerus , particularly in the anteroinferior, posterior and inferior directions (SOURCE-1). Assessment findings should always be compared to the asymptomatic side (SOURCE-2).

Orthopaedic Tests

Despite a lack of specificity or sensitivity, the following Shoulder - Special Tests can be used to evaluate for HAGL Lesions (SOURCE-2+3):

Neurological

With its course close to the 6 o’clock position on the Glenoid Labrum and frequent concomitant pathology, the Axillary Nerve should be evaluated for its integrity (SOURCE-2+3). Assessment includes sensory any motor tests (SOURCE-4)

Imaging

The following imaging modalities may be relevant in the evaluation of HAGL Lesions and common concomitant injury:

Magnetic Resonance Imaging (MRI)- with or without intra-articular contrast, the modality of choice for HAGL and PHAGL lesions (SOURCE-1+2). T-2 fat-suppressed images with aCoronal or Sagittal Oblique Viewtypically reveals a U-shaped Inferior Glenohumeral Ligament complex due to fluid distension in the axillary pouch which synovial fluid fills and expands the space (SOURCE-1+2). When this tissue is compromised and fluid sequestered, the axillary pouch more closely resembles a J-shape and the effusion of joint fluid (or intra-articular contrast dye) may be indicative of a HAGL lesion (SOURCE-1+2). A MR Arthrogram may be indicated if performed >7-10 days following injury as joint effusion will have likely diminished (SOURCE-3).

Radiography (X-Rays)- often the first line of assessment which may reveal osseous injury including Fracture s/ Avulsion Fractures of the Glenoid Rim or Head of Humerus , with the following views recommended (SOURCE-2+3):

  • True AP View - in both neutral and GH Joint - Internal Rotation

  • Scapular Y View

  • Axillary Lateral View

  • Garth View - may reveal a Bone fragment inferior to the anatomical neck

  • Arthrogram - dye that is normally contained in theAxillary pouch,Biceps SheathandSubcoracoid Recessleaks inferiorly into a crescent-shape


Treatment

Where no Glenohumeral Instability is present, conservative management of HAGL Lesions should be the first-line of treatment (SOURCE-3). The limited consensus appears The Shoulder Girdle should be immobilised in either neutral or slight GH Joint - Internal Rotation for the initial 4 weeks following injury, after which a Strength program may be commenced (SOURCE-2+3). Unfortunately, the vast majority (~90%) of HAGL Lesions managed non-operatively develop recurrent instability while those handled surgically do not share the same outcome (SOURCE-3).

Stretching

There is a paucity of literature regarding Stretching techniques for the treatment of HAGL lesions or following surgical repair. Irrespective of the procedure, there appears a consensus that shoulder motion should be restricted postoperatively for roughly a 4 week period with near full Range of Motion possible beyond the 12 week mark (SOURCE-2+3). This provides an approximate guide as to when rudimentary stretches may be commenced and how aggressively they should be progressed. Following most surgeries related to HAGL lesions, particular caution should be given to GH Joint - External Rotation and GH Joint - Internal Rotation to ensure tissues of focus are not further compromised. The following lists stretches that may be relevant in the treatment of HAGL lesions (SOURCE-2+3):Intial Phase - roughly the first 6 weeks following surgery, with the shoulder immobilised in a sling for the first 4 and only a select amount of shoulder motion permitted in this time

Mid-Phase - roughly weeks 6 to 12 following surgery, Range of Motion and the patients contribution to movement are cautiously progressed

Late Phase - beyond the 12 week mark the majoirty of shoulder motion should either be actively full or near full and more advanced streching techniques may be undertaken. As tolerated by the patient, this may include compound stretches performed with the intention of increasing Range of Motion and introducing forms of resistance to translate newly found Flexibility into functional Mobility . A return to sport should be anticipated by ~4 months (SOURCE-2):

Strengthening

Whether it be through conservative management or following surgery, Strength training forms an integral part of HAGL Lesion rehabilitation. With either intervention strategy, the time frames roughly align.

Initial Phase (<4 weeks) - exercises permitted within the first 4 weeks aim to alleviate Pain and Inflammation and begin to restore pain-free Range of Motion (SOURCE-2). Provocative movements should be avoided:

Mid-Phase (~4-10 weeks) - Range of Motion exercises should be commenced, in particular those that emphasise GH Joint - External Rotation (SOURCE-2). From ~6 weeks following injury or surgery resistance may be progressed (SOURCE-2):

Late Phase - exercise progression is continued with the aims of a full recovery (including return to sport) within 4 months (SOURCE-2). Exercise selection should consider increasing loads, range of motion and incorporating functional patterns, in particularly those that closely reflect the patients demands:

Surgery

While HAGL lesions can be managed conservatively, similar to other labral tears, they are associated with high rates of Glenohumeral Instability recurrence (SOURCE-1). Therefore, surgery may be indicated for individuals with persistent Pain or instability following conservative management. Likewise, surgical intervention is often recommended for young athletes and manual labourers who place high physical demands on The Shoulder Girdle (SOURCE-1).HAGL lesions are typically managed arthroscopically or through an open repair to re-anchor the torn ligament to its bony attachment on the Humeral Neck with sutures (SOURCE-2):

  • Arthroscopic Repair- this technique is less invasive, using small incisions guided by a camera. This approach causes less damage to surrounding tissues but requires more technical proficiency from the surgeon

  • Open Repair- this is a highly invasive procedure. It uses a large incision (a standard deltopectoral approach) to gain access to the joint by dissecting through and detaching the Subscapularis muscle

  • Mini-Open Technique- a less invasive variation of the open approach has also been described, which preserves the superior 50% of the Subscapularis Tendon

Undiagnosed cases of HAGL are believed to be a notable reason for failed anterior stabilisation surgeries. 18% of anterior stabilisation surgeries for Glenohumeral Instability where found to have a HAGL lesion (SOURCE-3).


References

  1. Longo, U. G., Rizzello, G., Ciuffreda, M., Locher, J., Berton, A., Salvatore, G., & Denaro, V. (2016). Humeral Avulsion of the Glenohumeral Ligaments: A Systematic Review. Arthroscopy : the journal of arthroscopic & related surgery : official publication of the Arthroscopy Association of North America and the International Arthroscopy Association, 32(9), 1868–1876. https://doi.org/10.1016/j.arthro.2016.03.009

  2. Grimm, N. L., Jimenez, A. E., & Arciero, R. A. (2020). Management of humeral avulsion of the glenohumeral ligament (HAGL) lesion. Operative Techniques in Orthopaedics, 30(3), Article 100820. https://doi.org/10.1016/j.oto.2020.100820

  3. Massey, P., & McClary, K. (2025, May 10). Humeral avulsion glenohumeral ligament (HAGL). Orthobullets. https://www.orthobullets.com/shoulder-and-elbow/322184/humeral-avulsion-glenohumeral-ligament-hagl?section=bullets

  4. Vedova, F. D., Ibáñez, M., Alvarez, V., Lépore, S., Sulzle, V. O., Galan, H., & Slullitel, D. (2015). Posterior humeral avulsion of the glenohumeral ligament (PHAGL) in anterior shoulder instability. Orthopaedic Journal of Sports Medicine, 2(4 Suppl), 2325967114S00249. https://doi.org/10.1177/2325967114S00249

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