- Email: [email protected]
Glenoid Avulsion of the Glenohumeral Ligaments as a Cause of Recurrent Anterior Shoulder Instability
Case Report With Video Illustration
Glenoid Avulsion of the Glenohumeral Ligaments as a Cause of Recurrent Anterior Shoulder Instability Eugene M. Wolf, M.D., and Patrick N. Siparsky, M.D.
Abstract: Although the Bankart lesion is accepted as the primary pathology responsible for recurrent shoulder instability, recognition of other soft-tissue lesions has improved the surgical treatment for this common problem. Whereas humeral avulsion of the glenohumeral ligaments has been acknowledged as a cause of anterior shoulder instability, we have not found any reported cases of glenoid avulsion of the glenohumeral ligaments. We describe 3 cases of recurrent anterior shoulder instability due to glenoid avulsion of the glenohumeral ligaments. The avulsed ligaments were repaired to the labrum and glenoid, restoring the glenohumeral ligament–labral complex.
R
ecurrent anterior shoulder instability is a common problem after traumatic shoulder dislocation. From subluxations to recurrent dislocations, shoulder instability can cause significant disability in patients of all ages. The Bankart lesion is well recognized as the most commonly associated pathology in traumatic shoulder instability, but other injuries involving the glenohumeral ligaments have been more recently identified. In 1995 humeral avulsion of the glenohumeral ligaments (HAGL) was found to be the primary pathology in 6 of 64 shoulders (9.3%) with anterior shoulder instability.1 Subsequently, several authors have identified other pathologies responsible for shoulder instability. Posterior humeral avulsion of the glenohumeral ligaments, or “reverse” HAGL (RHAGL), was iden-
From the Sportsmed Orthopaedic Group (E.M.W.), San Francisco, California; and San Francisco Orthopaedic Residency Program, St. Mary’s Hospital (P.N.S.), San Francisco, California, U.S.A. Address correspondence and reprint requests to Patrick N. Siparsky, M.D., San Francisco Orthopaedic Residency Program, St Mary’s Hospital, 450 Stanyan St, San Francisco, CA 94117, U.S.A. E-mail: [email protected] © 2010 by the Arthroscopy Association of North America 0749-8063/10309/$36.00 doi:10.1016/j.arthro.2010.06.005 Note: To access the video accompanying this report, visit the September issue of Arthroscopy at www.arthroscopyjournal.org.
tified by Chhabra et al.2 as a cause for posterior instability, whereas Hill et al.3 reported similar instability in an athlete with a RHAGL lesion and posterior Bankart. Oberlander et al.4 described bony avulsion of the glenohumeral ligaments from the humerus (BHAGL), characterized by a bony fragment avulsing from the humerus with the glenohumeral ligaments. Field et al.5 and Warner et al.6 have described the combination of a Bankart with a HAGL as the “floating lesion.” The purpose of this article is to present 3 cases of a newly recognized pathology responsible for anterior shoulder instability: glenoid avulsion of the glenohumeral ligaments (GAGL) (Table 1). Since the initial identification of the GAGL lesion, we have performed 29 instability procedures and found 2 additional GAGL lesions. Typically, the most common pathology on the glenoid side after traumatic dislocation is avulsion of the glenohumeral ligament–labral complex (Bankart lesion). In these 3 cases the anterior glenohumeral ligaments were torn from the labrum. The first and second cases involved detachment of the glenohumeral ligaments from a frayed but intact labrum. The third case had a GAGL lesion with a detached labrum, leaving a “floating labrum.” This differs from the “floating lesion” previously described as a HAGL lesion with a Bankart lesion.5,6 In this case the glenohumeral ligaments were detached from the labrum, which itself was detached from the glenoid.
Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 26, No 9 (September), 2010: pp 1263-1267
1263
1264
E. M. WOLF AND P. N. SIPARSKY TABLE 1.
Patient Information
Case No.
Age (yr)
Sex
Side
Mechanism
Duration
Prior Surgery
1 2 3
50 31 27
F M M
R R R
Basketball Skiing Snowboarding
3 wk 2 wk 8 yr
Scope x 2 None None
CASE 1 An active and healthy 50-year-old woman sustained her first right shoulder dislocation while playing basketball. The dislocation was reduced in the emergency department. She was immobilized for 1 week and then had 3 weeks of normal shoulder activity before dislocating again with the arm in abduction and external rotation. She required another physician-assisted reduction. The patient was seen by another surgeon who recommended an arthroscopic stabilization. At the time of that surgery, it was noted that the labrum was completely intact; however, the patient was thought to have a HAGL lesion. Because the patient did not consent to undergo an open procedure, the surgeon referred her to our office for possible arthroscopic repair. The patient was examined under anesthesia in the lateral decubitus position. The scapula was stabilized and the arm placed in abduction– external rotation. A compressive force was then applied to the glenoid through axial compression of the humerus. Translational forces were applied in the anterior, inferior, and posterior planes. The shoulder was found to have purely anterior instability. After initial arthroscopic evaluation of the shoulder joint from the posterior portal, anterior-superior and anterior-inferior portals were created. The arthroscope
was switched to the anterior-superior portal and the probe placed in the anterior-inferior portal. Arthroscopic evaluation of the humeral attachments of the glenohumeral ligaments did not show a HAGL lesion. However, further inspection of the joint from the anterior-superior portal showed detachment of the glenohumeral ligaments from an intact labrum (Fig 1). The patient also had a superficial Hill-Sachs lesion. To address the GAGL lesion, the margins of the glenohumeral ligaments and labrum were freshened with a shaver, and the ligaments were repaired to the intact labrum with multiple No. 1 PDS sutures (Ethicon, Somerville, NJ) (Video 1, available at www.arthroscopyjournal .org). Capsular redundancy was eliminated, and the glenohumeral ligament–labral complex was restored (Fig 2). CASE 2 A 31-year-old healthy man had a history of multiple subluxations. He subsequently sustained a traumatic right shoulder dislocation during a fall while skiing. He described a fall with the arm extended and externally rotated. The shoulder was reduced at the resort, and the patient was seen at our office less than 2 weeks after injury. Radiographs were initially ordered and showed a small Hill-Sachs lesion. Subsequently, a magnetic resonance imaging study showed labral stripping, but there was no Bankart lesion found (Fig 3). Treatment options were discussed, and the patient elected to undergo an arthroscopic stabilization. Surgery took place 1 month 6 days after dislocation. The patient was positioned and examined under anesthesia as described previously and had anterior instability only. We were able to visualize the avul-
FIGURE 1. GAGL lesion in case 1: Initial evaluation of GAGL lesion from anterior-superior portal of right shoulder with patient in lateral decubitus position. (A) Humeral head (H), glenoid (G), and labrum (L) with avulsed inferior glenohumeral ligament (GHL). (B) Artistic rendition of GAGL lesion.
GAGL AND ANTERIOR SHOULDER INSTABILITY
1265
FIGURE 2. Direct repair to labrum in case 1: Anterior-superior portal view of right shoulder with patient in lateral decubitus position. (A) Suture passer through inferior glenohumeral ligament (GHL) heading toward labrum (L). (B) Initial suture closing GAGL defect between labrum and GHL. (C) GAGL lesion repaired with multiple sutures.
sion of the glenohumeral ligaments from the glenoid labrum. A probe was used to carefully inspect the labrum and its attachment to the glenoid. The labrum was frayed but attached (Fig 4A). The avulsed glenohumeral ligaments were repaired to the intact anterior labrum by use of 4 No. 1 PDS sutures placed through the anterior-inferior portal (Figs 4B and 4C).
CASE 3 A 27-year-old healthy man had an 8-year history of anterior instability and multiple dislocations requiring physician-assisted relocation. The original traumatic injury to the right shoulder occurred while snowboarding. The patient was noted to have a large Hill-Sachs lesion on radiography. He was scheduled for arthroscopic surgical stabilization. This patient was examined in a similar fashion as described previously for case 1. The examination under anesthesia showed anterior instability. Arthroscopy showed that the glenohumeral ligaments were avulsed and healed medially on the glenoid (Fig 5A). The anterior labrum was detached from the glenoid from the 2- to 6-o’clock position but was not displaced medially with the ligaments (Fig 5B). A large Hill-Sachs lesion was present. Elevation of the tissue from the scapular neck showed it to be ligamentous tissue only, showing that this was not an anterior labral periosteal sleeve avulsion. After mobilization, the glenohumeral ligaments were sutured to the labrum and restored to the glenoid rim with 3 suture anchors (Fig 5C). DISCUSSION
FIGURE 3. Magnetic resonance imaging in case 2 with GAGL lesion: Axial section of right shoulder. The arrow points to abnormality at the anterior labrum suggestive of glenohumeral ligament injury. The musculoskeletal radiologist read the image as showing a Bankart variant with capsular injury and stripping.
The glenohumeral ligament–labral complex has been shown to play a significant role in shoulder stability. The spectrum of pathology sustained with traumatic shoulder dislocation has expanded beyond the Bankart lesion to include the HAGL and other glenohumeral ligament injuries. Historically, the Bankart lesion has dominated most discussions concerning shoulder instability because greater than 70% of traumatic anterior dislocations show this anterior-inferior labral defect.1,6-8 This includes bony
1266
E. M. WOLF AND P. N. SIPARSKY
FIGURE 4. GAGL lesion in case 2: Anterior-superior portal view of right shoulder with patient in lateral decubitus position. (A) The labrum (L) and inferior glenohumeral ligament (GHL) are outlined. The GAGL defect is between them. (B) Initial PDS suture placed through GHL and labrum. (C) Re-tensioned GHL (arrow) with multi-suture repair. Capsular redundancy has been eliminated.
Bankart lesions and resulting bone loss that have been held responsible for failures with arthroscopic shoulder stabilization.9,10 Recent identification of glenohumeral ligament injuries responsible for shoulder instability requires our careful attention. The glenohumeral ligaments play a significant role in shoulder stability throughout motion. The inferior glenohumeral ligament is crucial for restricting anterior and inferior shoulder displacement as the arm abducts and externally rotates. Bigliani et al.,11 in a biomechanical study, defined failure sites of the inferior glenohumeral ligament: the glenoid insertion (40%), the ligament substance (35%), and the humeral insertion (24%). Despite the results of this study and prior reports of capsular avulsions,12,13 glenohumeral ligament injuries remained underappreciated. The current literature regarding glenohumeral liga-
ment injury after traumatic shoulder dislocation continues to grow, now including the HAGL, BHAGL, and RHAGL lesions.1-8,14-26 It is critical for the arthroscopic surgeon to be aware of these lesions and treat them appropriately to avoid recurrent instability. Bokor et al.7 retrospectively identified 130 shoulders out of 529 in a 7-year series of anterior shoulder instability in which there was no Bankart lesion. Of these shoulders, 35 were found to have a HAGL lesion. This suggests that 26.9% of patients in this series presenting without a Bankart lesion had a HAGL lesion. The authors note that 7.5% of all of their patients with anterior glenohumeral instability had a HAGL lesion. This is comparable to several more recent investigations suggesting between 1.5% and 4% of patients with anterior instability present with a HAGL lesion.18-21 As knowledge of the complex pathology of gle-
FIGURE 5. Torn glenohumeral ligaments and floating labrum in case 3: Anterior-superior portal view of right shoulder with patient in lateral decubitus position. (A) Inferior glenohumeral ligament (GHL) scarred medially to glenoid (G) at scapular neck. (B) Floating labrum with detachment of labrum (L) from glenoid (G) and GHL. (C) Multi-suture repair of floating labrum incorporating glenohumeral ligament repair.
GAGL AND ANTERIOR SHOULDER INSTABILITY nohumeral ligament lesions increases, arthroscopy has allowed for better characterization and repair techniques to evolve. Whereas the original HAGL repair used only a 30° arthroscope and sutures, several authors now recommend the use of suture anchors22-24 and a 70° arthroscope.22,23 Multiple investigations now discuss arthroscopic repair techniques for RHAGL lesions.3,15,25,26 Care must be taken by the arthroscopist to evaluate all possible lesions that may be associated with the RHAGL. Reports of infraspinatus rupture15 and posterior Bankart3,26 have been described in association with the RHAGL lesion. In this report the GAGL lesion was noted in 3 patients sustaining traumatic shoulder dislocation. Of the 30 patients we treated surgically with shoulder instability in 1 year, 3 were noted to have the GAGL lesion. The GAGL lesion, like the HAGL lesion, is usually found in the setting of a frayed but still attached labrum. This pathology is best visualized with a 30° arthroscope in the anterior-superior portal and repaired with instrumentation in the anterior-inferior portal. We continue to expand our knowledge of the pathology of shoulder instability and to search for ways to improve the results of surgical repairs. Although the Bankart lesion is the most commonly found pathology in recurrent dislocations, recognition and treatment of glenohumeral ligament lesions such as the GAGL should improve our surgical outcomes. REFERENCES 1. Wolf EM, Cheng JC, Dickson K. Humeral avulsion of glenohumeral ligaments as a cause of anterior shoulder instability. Arthroscopy 1995;11:600-607. 2. Chhabra A, Diduch DR, Anderson M. Arthroscopic repair of a posterior humeral avulsion of the inferior glenohumeral ligament (HAGL) lesion. Arthroscopy 2004;20:73-76 (Suppl 2). 3. Hill JD, Lovejoy JF, Jr, Kelly RA. Combined posterior Bankart lesion and posterior humeral avulsion of the glenohumeral ligaments associated with recurrent posterior shoulder instability. Arthroscopy 2007;23:327.e1-327.e3. Available online at www .arthroscopyjournal.org. 4. Oberlander MA, Morgan BE, Visotsky JL. The BHAGL lesion: A new variant of anterior shoulder instability. Arthroscopy 1996;12:627-633. 5. Field LD, Bokor DJ, Savoie FH III. Humeral and glenoid detachment of the anterior inferior glenohumeral ligament: A cause of anterior shoulder instability. J Shoulder Elbow Surg 1997;6:6-10. 6. Warner JJ, Beim GM. Combined Bankart and HAGL lesion associated with anterior shoulder instability. Arthroscopy 1997;13:749-752. 7. Bokor DJ, Conboy VB, Olson C. Anterior instability of the glenohumeral joint with humeral avulsion of the glenohumeral ligament. A review of 41 cases. J Bone Joint Surg Br 1999; 81:93-96.
1267
8. Bui-Mansfield LT, Banks KP, Taylor DC. Humeral avulsion of the glenohumeral ligaments: The HAGL lesion. Am J Sports Med 2007;35:1960-1966. 9. Burkhart SS, De Beer JF. Traumatic glenohumeral bone defects and their relationship to failure of arthroscopic Bankart repairs: Significance of the inverted-pear glenoid and the humeral engaging Hill-Sachs lesion. Arthroscopy 2000;16:677694. 10. Lo IK, Parten PM, Burkhart SS. The inverted pear glenoid: An indicator of significant glenoid bone loss. Arthroscopy 2004; 20:169-174. 11. Bigliani LU, Pollock RG, Soslowsky LJ, Flatow EL, Pawluk RJ, Mow VC. Tensile properties of the inferior glenohumeral ligament. J Orthop Res 1992;10:187-197. 12. Bach BR, Warren RF, Fronek J. Disruption of the lateral capsule of the shoulder. A cause of recurrent dislocation. J Bone Joint Surg Br 1988;70:274-276. 13. Nicola T. Anterior dislocation of the shoulder: The role of the articular capsule. J Bone Joint Surg Br 1942;25:614-616. 14. Bokor DJ, Fritsch BA. Posterior shoulder instability secondary to reverse humeral avulsion of the glenohumeral ligament. J Shoulder Elbow Surg in press, available online 26 April, 2010. doi:10.1016/j.jse.2010.01.026 15. Brown T, Barton RS, Savoie FH III. Reverse humeral avulsion glenohumeral ligament and infraspinatus rupture with arthroscopic repair: A case report. Am J Sports Med 2007;35: 2135-2139. 16. Castagna A, Snyder SJ, Conti M, Borroni M, Massazza G, Garofalo R. Posterior humeral avulsion of the glenohumeral ligament: A clinical review of 9 cases. Arthroscopy 2007;23: 809-815. 17. Abrams JS, Savoie FH III, Tauro JC, Bradley JP. Recent advances in the evaluation and treatment of shoulder instability: Anterior, posterior, and multidirectional. Arthroscopy 2002;18:1-13. 18. Yiannakopoulos CK, Mataragas E, Antonogiannakis E. A comparison of the spectrum of intra-articular lesions in acute and chronic anterior shoulder instability. Arthroscopy 2007; 23:985-990. 19. DeBerardino TM, Arciero RA, Taylor DC, Uhorchak JM. Prospective evaluation of arthroscopic stabilization of acute, initial anterior shoulder dislocations in young athletes. Two- to five-year follow-up. Am J Sports Med 2001;29:586-592. 20. Rhee YG, Cho NS. Anterior shoulder instability with humeral avulsion of the glenohumeral ligament lesion. J Shoulder Elbow Surg 2007;16:188-192. 21. Mizuno N, Yoneda M, Hayashida K, Nakagawa S, Mae T, Izawa K. Recurrent anterior shoulder dislocation caused by a midsubstance complete capsular tear. J Bone Joint Surg Am 2005;87:2717-2723. 22. Richards DP, Burkhart SS. Arthroscopic humeral avulsion of the glenohumeral ligaments (HAGL) repair. Arthroscopy 2004;20:134-141 (Suppl 2). 23. Kon Y, Shiozaki H, Sugaya H. Arthroscopic repair of a humeral avulsion of the glenohumeral ligament lesion. Arthroscopy 2005;21:632.e1-632.e6. Available online at www.arthroscopyjournal.org. 24. Spang JT, Karas SG. The HAGL lesion: An arthroscopic technique for repair of humeral avulsion of the glenohumeral ligaments. Arthroscopy 2005;21:498-502. 25. Safran O, Defranco MJ, Hatem S, Iannotti JP. Posterior humeral avulsion of the glenohumeral ligament as a cause of posterior shoulder instability. A case report. J Bone Joint Surg Am 2004;86:2732-2736. 26. Pokabla C, Hobgood ER, Field LD. Identification and management of “floating” posterior inferior glenohumeral ligament lesions. J Shoulder Elbow Surg 2010;19:314-317.
Glenoid Avulsion of the Glenohumeral Ligaments as a Cause of Recurrent Anterior Shoulder Instability Eugene M. Wolf, M.D., and Patrick N. Siparsky, M.D.
Abstract: Although the Bankart lesion is accepted as the primary pathology responsible for recurrent shoulder instability, recognition of other soft-tissue lesions has improved the surgical treatment for this common problem. Whereas humeral avulsion of the glenohumeral ligaments has been acknowledged as a cause of anterior shoulder instability, we have not found any reported cases of glenoid avulsion of the glenohumeral ligaments. We describe 3 cases of recurrent anterior shoulder instability due to glenoid avulsion of the glenohumeral ligaments. The avulsed ligaments were repaired to the labrum and glenoid, restoring the glenohumeral ligament–labral complex.
R
ecurrent anterior shoulder instability is a common problem after traumatic shoulder dislocation. From subluxations to recurrent dislocations, shoulder instability can cause significant disability in patients of all ages. The Bankart lesion is well recognized as the most commonly associated pathology in traumatic shoulder instability, but other injuries involving the glenohumeral ligaments have been more recently identified. In 1995 humeral avulsion of the glenohumeral ligaments (HAGL) was found to be the primary pathology in 6 of 64 shoulders (9.3%) with anterior shoulder instability.1 Subsequently, several authors have identified other pathologies responsible for shoulder instability. Posterior humeral avulsion of the glenohumeral ligaments, or “reverse” HAGL (RHAGL), was iden-
From the Sportsmed Orthopaedic Group (E.M.W.), San Francisco, California; and San Francisco Orthopaedic Residency Program, St. Mary’s Hospital (P.N.S.), San Francisco, California, U.S.A. Address correspondence and reprint requests to Patrick N. Siparsky, M.D., San Francisco Orthopaedic Residency Program, St Mary’s Hospital, 450 Stanyan St, San Francisco, CA 94117, U.S.A. E-mail: [email protected] © 2010 by the Arthroscopy Association of North America 0749-8063/10309/$36.00 doi:10.1016/j.arthro.2010.06.005 Note: To access the video accompanying this report, visit the September issue of Arthroscopy at www.arthroscopyjournal.org.
tified by Chhabra et al.2 as a cause for posterior instability, whereas Hill et al.3 reported similar instability in an athlete with a RHAGL lesion and posterior Bankart. Oberlander et al.4 described bony avulsion of the glenohumeral ligaments from the humerus (BHAGL), characterized by a bony fragment avulsing from the humerus with the glenohumeral ligaments. Field et al.5 and Warner et al.6 have described the combination of a Bankart with a HAGL as the “floating lesion.” The purpose of this article is to present 3 cases of a newly recognized pathology responsible for anterior shoulder instability: glenoid avulsion of the glenohumeral ligaments (GAGL) (Table 1). Since the initial identification of the GAGL lesion, we have performed 29 instability procedures and found 2 additional GAGL lesions. Typically, the most common pathology on the glenoid side after traumatic dislocation is avulsion of the glenohumeral ligament–labral complex (Bankart lesion). In these 3 cases the anterior glenohumeral ligaments were torn from the labrum. The first and second cases involved detachment of the glenohumeral ligaments from a frayed but intact labrum. The third case had a GAGL lesion with a detached labrum, leaving a “floating labrum.” This differs from the “floating lesion” previously described as a HAGL lesion with a Bankart lesion.5,6 In this case the glenohumeral ligaments were detached from the labrum, which itself was detached from the glenoid.
Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 26, No 9 (September), 2010: pp 1263-1267
1263
1264
E. M. WOLF AND P. N. SIPARSKY TABLE 1.
Patient Information
Case No.
Age (yr)
Sex
Side
Mechanism
Duration
Prior Surgery
1 2 3
50 31 27
F M M
R R R
Basketball Skiing Snowboarding
3 wk 2 wk 8 yr
Scope x 2 None None
CASE 1 An active and healthy 50-year-old woman sustained her first right shoulder dislocation while playing basketball. The dislocation was reduced in the emergency department. She was immobilized for 1 week and then had 3 weeks of normal shoulder activity before dislocating again with the arm in abduction and external rotation. She required another physician-assisted reduction. The patient was seen by another surgeon who recommended an arthroscopic stabilization. At the time of that surgery, it was noted that the labrum was completely intact; however, the patient was thought to have a HAGL lesion. Because the patient did not consent to undergo an open procedure, the surgeon referred her to our office for possible arthroscopic repair. The patient was examined under anesthesia in the lateral decubitus position. The scapula was stabilized and the arm placed in abduction– external rotation. A compressive force was then applied to the glenoid through axial compression of the humerus. Translational forces were applied in the anterior, inferior, and posterior planes. The shoulder was found to have purely anterior instability. After initial arthroscopic evaluation of the shoulder joint from the posterior portal, anterior-superior and anterior-inferior portals were created. The arthroscope
was switched to the anterior-superior portal and the probe placed in the anterior-inferior portal. Arthroscopic evaluation of the humeral attachments of the glenohumeral ligaments did not show a HAGL lesion. However, further inspection of the joint from the anterior-superior portal showed detachment of the glenohumeral ligaments from an intact labrum (Fig 1). The patient also had a superficial Hill-Sachs lesion. To address the GAGL lesion, the margins of the glenohumeral ligaments and labrum were freshened with a shaver, and the ligaments were repaired to the intact labrum with multiple No. 1 PDS sutures (Ethicon, Somerville, NJ) (Video 1, available at www.arthroscopyjournal .org). Capsular redundancy was eliminated, and the glenohumeral ligament–labral complex was restored (Fig 2). CASE 2 A 31-year-old healthy man had a history of multiple subluxations. He subsequently sustained a traumatic right shoulder dislocation during a fall while skiing. He described a fall with the arm extended and externally rotated. The shoulder was reduced at the resort, and the patient was seen at our office less than 2 weeks after injury. Radiographs were initially ordered and showed a small Hill-Sachs lesion. Subsequently, a magnetic resonance imaging study showed labral stripping, but there was no Bankart lesion found (Fig 3). Treatment options were discussed, and the patient elected to undergo an arthroscopic stabilization. Surgery took place 1 month 6 days after dislocation. The patient was positioned and examined under anesthesia as described previously and had anterior instability only. We were able to visualize the avul-
FIGURE 1. GAGL lesion in case 1: Initial evaluation of GAGL lesion from anterior-superior portal of right shoulder with patient in lateral decubitus position. (A) Humeral head (H), glenoid (G), and labrum (L) with avulsed inferior glenohumeral ligament (GHL). (B) Artistic rendition of GAGL lesion.
GAGL AND ANTERIOR SHOULDER INSTABILITY
1265
FIGURE 2. Direct repair to labrum in case 1: Anterior-superior portal view of right shoulder with patient in lateral decubitus position. (A) Suture passer through inferior glenohumeral ligament (GHL) heading toward labrum (L). (B) Initial suture closing GAGL defect between labrum and GHL. (C) GAGL lesion repaired with multiple sutures.
sion of the glenohumeral ligaments from the glenoid labrum. A probe was used to carefully inspect the labrum and its attachment to the glenoid. The labrum was frayed but attached (Fig 4A). The avulsed glenohumeral ligaments were repaired to the intact anterior labrum by use of 4 No. 1 PDS sutures placed through the anterior-inferior portal (Figs 4B and 4C).
CASE 3 A 27-year-old healthy man had an 8-year history of anterior instability and multiple dislocations requiring physician-assisted relocation. The original traumatic injury to the right shoulder occurred while snowboarding. The patient was noted to have a large Hill-Sachs lesion on radiography. He was scheduled for arthroscopic surgical stabilization. This patient was examined in a similar fashion as described previously for case 1. The examination under anesthesia showed anterior instability. Arthroscopy showed that the glenohumeral ligaments were avulsed and healed medially on the glenoid (Fig 5A). The anterior labrum was detached from the glenoid from the 2- to 6-o’clock position but was not displaced medially with the ligaments (Fig 5B). A large Hill-Sachs lesion was present. Elevation of the tissue from the scapular neck showed it to be ligamentous tissue only, showing that this was not an anterior labral periosteal sleeve avulsion. After mobilization, the glenohumeral ligaments were sutured to the labrum and restored to the glenoid rim with 3 suture anchors (Fig 5C). DISCUSSION
FIGURE 3. Magnetic resonance imaging in case 2 with GAGL lesion: Axial section of right shoulder. The arrow points to abnormality at the anterior labrum suggestive of glenohumeral ligament injury. The musculoskeletal radiologist read the image as showing a Bankart variant with capsular injury and stripping.
The glenohumeral ligament–labral complex has been shown to play a significant role in shoulder stability. The spectrum of pathology sustained with traumatic shoulder dislocation has expanded beyond the Bankart lesion to include the HAGL and other glenohumeral ligament injuries. Historically, the Bankart lesion has dominated most discussions concerning shoulder instability because greater than 70% of traumatic anterior dislocations show this anterior-inferior labral defect.1,6-8 This includes bony
1266
E. M. WOLF AND P. N. SIPARSKY
FIGURE 4. GAGL lesion in case 2: Anterior-superior portal view of right shoulder with patient in lateral decubitus position. (A) The labrum (L) and inferior glenohumeral ligament (GHL) are outlined. The GAGL defect is between them. (B) Initial PDS suture placed through GHL and labrum. (C) Re-tensioned GHL (arrow) with multi-suture repair. Capsular redundancy has been eliminated.
Bankart lesions and resulting bone loss that have been held responsible for failures with arthroscopic shoulder stabilization.9,10 Recent identification of glenohumeral ligament injuries responsible for shoulder instability requires our careful attention. The glenohumeral ligaments play a significant role in shoulder stability throughout motion. The inferior glenohumeral ligament is crucial for restricting anterior and inferior shoulder displacement as the arm abducts and externally rotates. Bigliani et al.,11 in a biomechanical study, defined failure sites of the inferior glenohumeral ligament: the glenoid insertion (40%), the ligament substance (35%), and the humeral insertion (24%). Despite the results of this study and prior reports of capsular avulsions,12,13 glenohumeral ligament injuries remained underappreciated. The current literature regarding glenohumeral liga-
ment injury after traumatic shoulder dislocation continues to grow, now including the HAGL, BHAGL, and RHAGL lesions.1-8,14-26 It is critical for the arthroscopic surgeon to be aware of these lesions and treat them appropriately to avoid recurrent instability. Bokor et al.7 retrospectively identified 130 shoulders out of 529 in a 7-year series of anterior shoulder instability in which there was no Bankart lesion. Of these shoulders, 35 were found to have a HAGL lesion. This suggests that 26.9% of patients in this series presenting without a Bankart lesion had a HAGL lesion. The authors note that 7.5% of all of their patients with anterior glenohumeral instability had a HAGL lesion. This is comparable to several more recent investigations suggesting between 1.5% and 4% of patients with anterior instability present with a HAGL lesion.18-21 As knowledge of the complex pathology of gle-
FIGURE 5. Torn glenohumeral ligaments and floating labrum in case 3: Anterior-superior portal view of right shoulder with patient in lateral decubitus position. (A) Inferior glenohumeral ligament (GHL) scarred medially to glenoid (G) at scapular neck. (B) Floating labrum with detachment of labrum (L) from glenoid (G) and GHL. (C) Multi-suture repair of floating labrum incorporating glenohumeral ligament repair.
GAGL AND ANTERIOR SHOULDER INSTABILITY nohumeral ligament lesions increases, arthroscopy has allowed for better characterization and repair techniques to evolve. Whereas the original HAGL repair used only a 30° arthroscope and sutures, several authors now recommend the use of suture anchors22-24 and a 70° arthroscope.22,23 Multiple investigations now discuss arthroscopic repair techniques for RHAGL lesions.3,15,25,26 Care must be taken by the arthroscopist to evaluate all possible lesions that may be associated with the RHAGL. Reports of infraspinatus rupture15 and posterior Bankart3,26 have been described in association with the RHAGL lesion. In this report the GAGL lesion was noted in 3 patients sustaining traumatic shoulder dislocation. Of the 30 patients we treated surgically with shoulder instability in 1 year, 3 were noted to have the GAGL lesion. The GAGL lesion, like the HAGL lesion, is usually found in the setting of a frayed but still attached labrum. This pathology is best visualized with a 30° arthroscope in the anterior-superior portal and repaired with instrumentation in the anterior-inferior portal. We continue to expand our knowledge of the pathology of shoulder instability and to search for ways to improve the results of surgical repairs. Although the Bankart lesion is the most commonly found pathology in recurrent dislocations, recognition and treatment of glenohumeral ligament lesions such as the GAGL should improve our surgical outcomes. REFERENCES 1. Wolf EM, Cheng JC, Dickson K. Humeral avulsion of glenohumeral ligaments as a cause of anterior shoulder instability. Arthroscopy 1995;11:600-607. 2. Chhabra A, Diduch DR, Anderson M. Arthroscopic repair of a posterior humeral avulsion of the inferior glenohumeral ligament (HAGL) lesion. Arthroscopy 2004;20:73-76 (Suppl 2). 3. Hill JD, Lovejoy JF, Jr, Kelly RA. Combined posterior Bankart lesion and posterior humeral avulsion of the glenohumeral ligaments associated with recurrent posterior shoulder instability. Arthroscopy 2007;23:327.e1-327.e3. Available online at www .arthroscopyjournal.org. 4. Oberlander MA, Morgan BE, Visotsky JL. The BHAGL lesion: A new variant of anterior shoulder instability. Arthroscopy 1996;12:627-633. 5. Field LD, Bokor DJ, Savoie FH III. Humeral and glenoid detachment of the anterior inferior glenohumeral ligament: A cause of anterior shoulder instability. J Shoulder Elbow Surg 1997;6:6-10. 6. Warner JJ, Beim GM. Combined Bankart and HAGL lesion associated with anterior shoulder instability. Arthroscopy 1997;13:749-752. 7. Bokor DJ, Conboy VB, Olson C. Anterior instability of the glenohumeral joint with humeral avulsion of the glenohumeral ligament. A review of 41 cases. J Bone Joint Surg Br 1999; 81:93-96.
1267
8. Bui-Mansfield LT, Banks KP, Taylor DC. Humeral avulsion of the glenohumeral ligaments: The HAGL lesion. Am J Sports Med 2007;35:1960-1966. 9. Burkhart SS, De Beer JF. Traumatic glenohumeral bone defects and their relationship to failure of arthroscopic Bankart repairs: Significance of the inverted-pear glenoid and the humeral engaging Hill-Sachs lesion. Arthroscopy 2000;16:677694. 10. Lo IK, Parten PM, Burkhart SS. The inverted pear glenoid: An indicator of significant glenoid bone loss. Arthroscopy 2004; 20:169-174. 11. Bigliani LU, Pollock RG, Soslowsky LJ, Flatow EL, Pawluk RJ, Mow VC. Tensile properties of the inferior glenohumeral ligament. J Orthop Res 1992;10:187-197. 12. Bach BR, Warren RF, Fronek J. Disruption of the lateral capsule of the shoulder. A cause of recurrent dislocation. J Bone Joint Surg Br 1988;70:274-276. 13. Nicola T. Anterior dislocation of the shoulder: The role of the articular capsule. J Bone Joint Surg Br 1942;25:614-616. 14. Bokor DJ, Fritsch BA. Posterior shoulder instability secondary to reverse humeral avulsion of the glenohumeral ligament. J Shoulder Elbow Surg in press, available online 26 April, 2010. doi:10.1016/j.jse.2010.01.026 15. Brown T, Barton RS, Savoie FH III. Reverse humeral avulsion glenohumeral ligament and infraspinatus rupture with arthroscopic repair: A case report. Am J Sports Med 2007;35: 2135-2139. 16. Castagna A, Snyder SJ, Conti M, Borroni M, Massazza G, Garofalo R. Posterior humeral avulsion of the glenohumeral ligament: A clinical review of 9 cases. Arthroscopy 2007;23: 809-815. 17. Abrams JS, Savoie FH III, Tauro JC, Bradley JP. Recent advances in the evaluation and treatment of shoulder instability: Anterior, posterior, and multidirectional. Arthroscopy 2002;18:1-13. 18. Yiannakopoulos CK, Mataragas E, Antonogiannakis E. A comparison of the spectrum of intra-articular lesions in acute and chronic anterior shoulder instability. Arthroscopy 2007; 23:985-990. 19. DeBerardino TM, Arciero RA, Taylor DC, Uhorchak JM. Prospective evaluation of arthroscopic stabilization of acute, initial anterior shoulder dislocations in young athletes. Two- to five-year follow-up. Am J Sports Med 2001;29:586-592. 20. Rhee YG, Cho NS. Anterior shoulder instability with humeral avulsion of the glenohumeral ligament lesion. J Shoulder Elbow Surg 2007;16:188-192. 21. Mizuno N, Yoneda M, Hayashida K, Nakagawa S, Mae T, Izawa K. Recurrent anterior shoulder dislocation caused by a midsubstance complete capsular tear. J Bone Joint Surg Am 2005;87:2717-2723. 22. Richards DP, Burkhart SS. Arthroscopic humeral avulsion of the glenohumeral ligaments (HAGL) repair. Arthroscopy 2004;20:134-141 (Suppl 2). 23. Kon Y, Shiozaki H, Sugaya H. Arthroscopic repair of a humeral avulsion of the glenohumeral ligament lesion. Arthroscopy 2005;21:632.e1-632.e6. Available online at www.arthroscopyjournal.org. 24. Spang JT, Karas SG. The HAGL lesion: An arthroscopic technique for repair of humeral avulsion of the glenohumeral ligaments. Arthroscopy 2005;21:498-502. 25. Safran O, Defranco MJ, Hatem S, Iannotti JP. Posterior humeral avulsion of the glenohumeral ligament as a cause of posterior shoulder instability. A case report. J Bone Joint Surg Am 2004;86:2732-2736. 26. Pokabla C, Hobgood ER, Field LD. Identification and management of “floating” posterior inferior glenohumeral ligament lesions. J Shoulder Elbow Surg 2010;19:314-317.