Summary Humeral Avulsion of the Glenohumeral Ligament (HAGL) is an injury to the inferior glenohumeral ligament causing instability and/or pain and a missed cause of recurrent shoulder instability. Diagnosis requires suspicions of injury and can be noted as an inferior pouch irregularity on MRI. Non-operative first-line treatment for acute presentation includes sling immobilization and physical therapy while operative treatment is recommended for recurrent instability. Epidemiology Incidence 1.6% of patients with shoulder pain Demographics male > female (94% male) average age 25-30 Anatomic location anterior band most common (93%) medial (glenoid) versus lateral (humerus) failure IGHL at labral complex - 40% intrasubstance tear - 35 % humeral insertion - 25% Risk factors 10% of recurrent anterior shoulder dislocators have HAGL 27% of shoulder instability patients without bankart have HAGL 18% of failed anterior stabilization have HAGL Etiology Pathophysiology mechanism of injury hyperabduction and external rotation is the main mechanism diving, Football, Basketball, Volleyball, Surfing, skiing, MVC Associated conditions orthopedic conditions labral tears - 25% rotator Cuff tears - 23% Hill-Sachs Deformity - 17% bony Bankart Anatomy Static stabilizers glenohumeral ligaments glenoid labrum attachment of glenohumeral ligaments deepens glenoid cavity articular congruity and version negative intraarticular pressure Dynamic stabilizers rotator cuff muscles the primary biomechanical role of the rotator cuff is stabilizing the glenohumeral joint by compressing the humeral head against the glenoid rotator interval biceps long head periscapular muscles deltoid Capsuloligamentous Complex coracohumeral Ligament superior glenohumeral ligament (SGHL) middle glenohumeral ligament (MGHL) inferior glenohumeral ligament (IGHL) hammock-like Structure anterior band - between 2 and 4 o'clock posterior Band - between 7 and 9 o'clock axillary pouch 2 types of Insertion on Humerus collar like attachment close to articular margin V-shaped attachment close to cartilage rim with apex distal on metaphysis Blood Supply anastamosis of branches of humeral sided and scapular sided vessels lateral: Anterior humeral circumflex artery, Posterior humeral circumflex artery medial: Suprascapular artery, Circumflex scapular arteries watershed area anterolaterally: near humeral insertion anterior capsule 3 cm medial to intertubercular groove Nervous system axillary nerve close to HAGL lesion at 6'oclock position (2-7mm, overestimated on MRI by 2mm) Biomechanics most taught between 45 - 90 degrees abduction anterior band of IGHL - anterior and inferior restraint taught at 90 degrees abduction and external rotation posterior band of IGHL- posterior and inferior restraint taught at 90 degrees abduction and internal rotation Classification West Point Classification - by Bui-Mansfield West Point Classification Based on 3 Factors: Anterior or Posterior Involvement Presence or Absence of Bony Avulsion Presence of Associated Labral Pathology (Floating) Anterior 93% Anterior HAGL 55% Anterior Bony HAGL 17% Floating AIGHL 21% Posterior 6% Posterior HAGL 2% Posterior Bony HAGL 0% Floating PIGHL 4% Presentation History position of arm at injury direction of instability recurrent instability failed surgery to correct instability Symptoms severe persistent pain after instability event recurrent instability Physical exam provocative tests apprehension and relocation tests load and shift posterior stress and posterior jerk tests sulcus sign in neutral and external rotation Neurovascular check axillary nerve function Imaging Radiographs recommended views true AP radiographs in neutral and internal rotation scapular Y axillary lateral findings glenoid rim fractures, hypoplasia, fractures of humeral head optional views Garth View 45-degree oblique radiograph in anterior plane fleck of bone inferior to anatomic neck - avulsion of medial cortex arthrogram normally dye appears in axillary pouch, biceps sheath, subcoracoid recess HAGL - dye escapes inferiorly in crescent shape CT indications lower utility than MRI consider combination with arthrogram for contraindication to MRI views best seen on sagittal findings Oberlander described bony HAGL lesion posterior to MGHL MRI indications gold standard for diagnosis of HAGL recurrent instability or persistent pain after instability event MR Arthrogram if more than 7 - 10 days from injury views coronal oblique T2 weighted fat suppressed MRI sagittal oblique T2 weighted fat suppressed MRI findings: J Sign pathopneumonic for HAGL inferior pouch normally appears U - Shaped HAGL has appearance of J - Shaped inferior pouch dye may leak through tear inferiorly chronic lesions may be difficult to see due to scar of IGHL to capsule Differential Anterior Bankart Tear/ Anterior Inferior Labrum tear Posterior Bankart/ Posterior Inferior Labrum tear Treatment Nonoperative sling immobilization and physical therapy indications first-line treatment when no instability present outcomes 90% recurrence rate of instability with non-operative treatment Operative open HAGL repair indications young person with primary shoulder dislocation, high recurrence rate associated injuries failed non-operative management recurrent instability persistent pain or instability after missed HAGL with Bankart repair techniques open anterior repair indications anterior HAGL open posterior repair indications posterior HAGL prognosis low incidence of post-operative instability following open repair no reported difference between open and arthroscopic repair arthroscopic HAGL repair indications same as open repair techniques anterior arthroscopic repair Indications anterior HAGL less soft tissue dissection compared to open less damage to subscapularis compared to open posterior arthroscopic repair Indications posterior HAGL avoid splitting rotator cuff muscles prognosis no reported difference between open and arthroscopic repair Techniques Sling immobilization and physical therapy Technique 4 week sling immobilization shoulder strengthening following sling immobilization period Open Anterior Repair advantages visualization of neurovascular structures less technically difficult approach deltopectoral approach 3 subscapularis approaches subscapularis tendon released leaving a 1cm cuff subscapularis sparing technique described by Arciero and Mazzoca L-shaped incision lower one third subscapularis tendon subscapularis sparing technique by Bhatia lower border subscapularis identified by anterior humeral circumflex pectoralis major tendon retracted inferiorly retract subscapularis superiorly subscapularis is usually scarred inferiorly with a HAGL technique bone preparation Medial humeral neck is rasped to remove scar tissue at 6 to 8 o'clock instrumentation suture anchor placed in inferior humerus necks sutures pulled through anterior-inferior capsule complications specific to this treatment axillary nerve entrapment use caution, nerve is within 3mm of inferior capsule rehabilitation anterior HAGL Protocol 0 - 4 weeks Sling Passive forward flexion to 90 degrees, external rotation to 30 degrees with arm at the side 4 - 10 weeks Assisted active forward flexion to 140 degrees External rotation to 40 degrees with arm at side 10 - 12 weeks External rotation permitted with 45 degrees of abduction Open Posterior Repair approach Judet approach deltoid bluntly spread in line with fibers interval between infraspinatous and teres minor utilized technique bone work Roughen bone inferiorly on humeral neck to create bleeding surface instrumentation Place suture anchors in inferior humeral neck rehabilitation posterior HAGL Protocol 0 - 6 weeks Passive abduction to 45 degrees, forward flexion to 45 degrees, external rotation to 30 degrees Internal rotation limited to arm against belly 6 weeks - 12 weeks No internal rotation with the arm abducted more than 45 degrees complications Axillary nerve entrapment use caution, nerve is within 3mm of inferior capsule Anterior Arthroscopic Repair approach 3 portal approach anterior superior portal under biceps anterior inferior portal above or below subscapularis posterior portal accessory Portals Anterior-inferior / 5 o'clock portal 1 cm inferior to upper border subscapularis tendon placed in neutral position to protect musculocutaneous nerve 7 o'clock posterior-inferior portal - Davidson and Rivenburgh 2 - 3 cm inferior to posterior viewing portal Bhatia portal/ axillary pouch portal 3 cm inferior to lower border of posterolateral acromial angle 2 cm lateral to standard posterior portal technique bone work humeral neck roughened with arthroscopic burr suture anchors placed at IGHL insertion on humeral neck soft tissue suture passing device through 5 o'clock portal horizontal mattress suture through capsular tissue to neck instrumentation suture lasso, suture anchors with curved guide wait until all sutures are passed to tie knots complications axillary nerve damage arthrofibrosis Posterior Arthroscopic Repair approach may Switch viewing portal from posterior to anterior using 30 degree scope accessory inferior-lateral posterior portal technique bone work shaver and burr to posterior humeral neck instrumentation place 2 suture anchors into inferior humeral neck posteriorly curved guide with all-suture anchor is helpful soft tissue use suture passer to pass sutures through posterior IGHL repair IGHL to posterior humeral neck tension sutures with arm externally rotated repair IGHL 1st (before bankart) with combined injuries Complications Arthrofibrosis with Loss of External Rotation Treatment Physical Therapy for external rotation stretching Axillary Nerve Injury Axillary nerve is 10 mm inferior to the glenoid and 2.5 mm inferior to capsule Chondrolysis risk factors reported with thermal capsulorrhaphy overtightening anterior may be associated with accelerated posterior wear Pulmonary Embolism Incidence 0.6% with shoulder arthroscopy Recurrence of instability Very Rare Per systematic review: 0/25 operative, 9/10 nonoperative Odds ratio 0.05 recurrence with operative vs nonoperative treatment (p=.006) Prognosis Good with adequate recognition and treatment