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Hill-Sachs Off-track Lesions as Risk Factor for Recurrence of Instability After Arthroscopic Bankart Repair
Hill-Sachs Off-track Lesions as Risk Factor for Recurrence of Instability After Arthroscopic Bankart Repair Joel Locher, M.D., Frauke Wilken, M.D., Knut Beitzel, M.D., Stefan Buchmann, M.D., Umile Giuseppe Longo, M.D., M.Sc., Ph.D., Vincenzo Denaro, M.D., and Andreas B. Imhoff, M.D.
Purpose: To evaluate the effect of “off-track” Hill-Sachs lesions, according to the glenoid track concept, as a risk factor for recurrent instability and need for revision surgery after arthroscopic Bankart repair. Methods: We retrospectively reviewed 254 patients with anteroinferior glenohumeral instability who were managed with an arthroscopic stabilization procedure between 2006 and 2013. Preoperative magnetic resonance imaging and/or computed tomography scans were available for 100 of these patients to calculate the glenoid track and the presence of “on-track” or off-track Hill-Sachs lesions. Recurrence of instability was evaluated at a mean follow-up of 22.4 months. Results: Of 100 patients whose magnetic resonance imaging and/or computed tomography scans were available, 88 had an on-track Hill-Sachs lesion and 12 had an off-track Hill-Sachs lesion. Revision surgery for recurrent instability was performed in 5 patients (6%) with an on-track Hill-Sachs lesion and in 4 patients (33%) with an off-track Hill-Sachs lesion (odds ratio, 8.3; 95% confidence interval, 1.85-37.26; P ¼ .006). Conclusions: An off-track Hill-Sachs lesion is a significant and important risk factor for recurrence of instability and need for revision surgery after arthroscopic Bankart repair when compared with an on-track Hill-Sachs lesion. Level of Evidence: Level IV, prognostic case series.
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rthroscopic Bankart repair is recognized as a successful procedure to address glenohumeral instability.1-6 The outcome for anteroinferior instability after arthroscopic Bankart repair is comparable with open techniques, with instability recurrence rates of 3.4% to 19%.2,7-12 Potential risk factors for recurrence after arthroscopic Bankart repair include sex, young age at the time of first surgery, joint hyperlaxity, bilateral shoulder instability, number of dislocations, participation in collision sports, early return to contact sports, bone defects, technical errors, and anterior From the Department of Orthopaedic and Trauma Surgery, Campus Bio-Medico University (J.L., U.G.L., V.D.), Rome, Italy; and Department of Orthopaedic Sports Medicine, Klinikum rechts der Isar, Technische Universität München (J.L., F.W., K.B., S.B., A.B.I.), Munich, Germany. The authors report that they have no conflicts of interest in the authorship and publication of this article. Received August 11, 2015; accepted March 4, 2016. Address correspondence to Andreas B. Imhoff, M.D., Department of Orthopaedic Sports Medicine, Klinikum rechts der Isar, Technische Universität München, Ismaninger Street 22, 81675 Munich, Germany. E-mail: [email protected] Ó 2016 by the Arthroscopy Association of North America 0749-8063/15760/$36.00 http://dx.doi.org/10.1016/j.arthro.2016.03.005
labroligamentous periosteal sleeve avulsion (ALPSA) lesions.2,13-17 Osseous integrity is a critical component of bony stability. Proper imaging is important to guide clinical decision making.18 Recently, both radiographic and arthroscopic methods, using the concept of the glenoid track, have been developed to determine whether a Hill-Sachs lesion will engage the anterior glenoid rim.19,20 The glenoid track is described as the zone of contact between the glenoid and the superolateral portion of the humeral head, with the arm in abduction, external rotation, and horizontal extension.21 An engaging Hill-Sachs lesion is also called an “off-track” Hill-Sachs lesion; if the Hill-Sachs lesion does not engage, it is an “on-track” lesion. An intact glenoid track, without significant bone loss, guarantees bony stability of the shoulder.19,22 The aim of this study was to evaluate the role of offtrack and on-track Hill-Sachs lesions as a risk factor for recurrence of instability and need for revision surgery. We hypothesized that an off-track Hill-Sachs lesion would be a risk factor for recurrence of instability and need for revision surgery after arthroscopic Bankart repair.
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Methods We retrospectively reviewed clinical records of all patients managed at our center with an arthroscopic stabilization procedure between 2006 and 2013 because of anteroinferior glenohumeral instability. The exclusion criteria were glenoid bone loss greater than 25% or other unrelated sources of shoulder pain, including acromioclavicular joint arthritis, brachial plexus lesions, and glenohumeral arthritis. Patients with posterior or multidirectional instability were also excluded. Only patients with preoperative magnetic resonance imaging (MRI) and/or computed tomography (CT) scans were included. Recurrence of instability was evaluated at a mean follow-up of 22.4 months. Surgical Technique The surgical technique for arthroscopic stabilization with anchors has been described previously.17 The patient is placed in the beach-chair position under general anesthesia, and the type and direction of the instability are confirmed by clinical examination. Diagnostic arthroscopy is performed from a posterior portal. Next, the anterosuperior portal is placed anterior to the acromioclavicular joint, slightly medial to the long biceps tendon and close to the glenoid rim. The stability of the labrum and the biceps tendon anchor is assessed with a probe. For anteroinferior labral lesions, the anterior labrum is mobilized with an elevator. Decortication of the glenoid neck is performed until punctate bleeding occurs. Next, a deep anteroinferior portal is placed about 8 to 10 cm distal to the coracoid process and lateral to the axillary fold. Under arthroscopic visualization, a Wissinger rod is inserted through the lower third of the subscapularis and a long clear arthroscopy cannula is advanced. The first suture anchor is implanted at the 5:30eclock face position, at the bone-cartilage junction of the glenoid margin. The capsulolabral complex is pierced with a curved hollow suture passer (through the anteroinferior portal) from inferior toward the anchor so that the whole capsulolabral complex including the anteroinferior glenohumeral ligament is incorporated. A suture lasso is then passed through the hollow suture passer. The suture passer is removed, and the suture lasso together with a suture limb is retrieved out the anterosuperior portal. The suture limb is passed through the loop of the suture lasso, which is then retrieved out through the capsulolabral complex so that, finally, both suture limbs of the anchor come out the anteroinferior portal. The suture limb passing through the capsulolabral complex serves as a “post” over which the knot is tied. The labrum is fixed with an arthroscopic sliding knot. Two additional suture anchors are usually inserted at the 4:30eclock face position and 3-o’clock position in the same technique. Refixation of the capsulolabral complex, as well as the mobility, is confirmed by
passively moving the shoulder under arthroscopic visualization. One surgeon (A.B.I.) either performed or directed all surgical procedures. Postoperative Management The arm is immobilized in a sling for 24 hours. Use of the sling is continued at night for 4 weeks. Rehabilitation begins on postoperative day 1 under the direction of a trained physical therapist, focusing on rotator cuff strengthening and range of motion (45 of active abduction and flexion and 80 to 30 of active internal and external rotation in weeks 1 through 3; 90 of active abduction and flexion and 80 to 0 of active internal and external rotation in weeks 4 through 6; afterward, free range of motion is allowed). Free motion of the elbow and wrist is encouraged. The rehabilitation program lasts for approximately 6 months. If an accompanying SLAP lesion is present, no active biceps training is permitted for 6 weeks. Full overhead sporting activities are allowed after 6 months. On- or Off-track Hill-Sachs Lesion Evaluation The measurements were performed using a similar technique to calculate the glenoid track and the presence of on- or off-track Hill-Sachs lesions, using MRI scans, which was recently described by Gyftopoulos et al.20 Preoperative MRI and/or CT scans, available for 100 of the 254 patients who underwent an arthroscopic stabilization procedure at our center, were used to evaluate on- or off-track Hill-Sachs lesions. According to the description of Di Giacomo et al.,19 a Hill-Sachs lesion is off track, or engaging, if the Hill-Sachs interval is greater than the glenoid track width; otherwise, the Hill-Sachs lesion is on track, or non-engaging. The Hill-Sachs interval, as described by Di Giacomo et al.,19 is the distance from the rotator cuff attachments to the medial rim of the Hill-Sachs lesion, and it is equal to the width of the Hill-Sachs lesion plus the width of the intact bone bridge between the rotator cuff and the Hill-Sachs lesion. We used a transverse-plane view of the shoulder, in the slice with the largest extension of the Hill-Sachs lesion, and measured these 2 distances (Fig 1). The Hill-Sachs interval was then obtained using the formula of Di Giacomo et al.: Hill-Sachs interval ¼ Width of Hill-Sachs lesion þ Width of bone bridge. The glenoid track width, without a glenoid defect, is 83% of the glenoid width. If there is a bony defect of the glenoid (d), the distance d is subtracted from 83% of the glenoid width. Therefore, the glenoid track width in the face of glenoid bone loss (d) is equal to 0.83 D d, in which D is the inferior glenoid diameter. Initially, we placed a best-fit circle along the posterior and inferior margins of the glenoid. The diameter D was obtained by doubling the measurement of the posterior radius of the glenoid in a sagittal-plane view, whereas the value for bone loss (d) was obtained by subtracting
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Fig 1. T2-weighted magnetic resonance image using a transverse-plane view of the left shoulder in the slice with the largest extension of the Hill-Sachs lesion. The Hill-Sachs interval is measured as the width of the Hill-Sachs lesion plus the width of the intact bone bridge between the rotator cuff and the Hill-Sachs lesion.
the measurement of the anteroinferior radius of the glenoid to the posterior radius (Fig 2). At this point, if the Hill-Sachs interval was greater than the glenoid track width, the Hill-Sachs lesion was off track, or engaging. If the Hill-Sachs interval was less than the glenoid track width, the Hill-Sachs lesion was on track, or non-engaging.19 All measurements were made by the same operator (J.L.), who was blinded to the patient’s history.
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male patients and 6 (21%) were female patients. The mean height was 177 cm (range, 160 to 195 cm), and the mean weight was 77.7 kg (range, 51 to 95 kg). The mean body mass index (BMI) value was 24.7; 15 patients had a normal or healthy weight (BMI, 18.5 to 25), whereas 8 were overweight (BMI, 25 to 30). The mean age at the time of initial surgery was 22.5 years (range, 9 to 37 years), and the mean age at revision surgery was 27 years (range, 15 to 45 years). The left shoulder was involved in 17 patients (59%) and the right in the remaining 12 (41%). Of the 29 patients, 23 (79%) were involved in sports. General hyperlaxity was reported by 2 patients (7%). In addition, 3 patients (10%) had epilepsy. A Hill-Sachs lesion was reported in 17 patients (59%) and a bony glenoid lesion was reported in 12 patients (41%) undergoing revision surgery for anteroinferior shoulder instability after arthroscopic Bankart repair. Both a Hill-Sachs lesion and a bony glenoid lesion were reported in 8 patients (28%). The size of the bony glenoid defect was always under 25% of the glenoid surface. A SLAP type V lesion was observed in 1 patient (3%). The number of dislocations before initial surgery was reported for 8 patients (28%). These patients had a mean of 3.1 dislocations before initial surgery (range, 1 to 5). The number of dislocations before revision surgery was reported for 15 patients (52%). These patients had a mean of 2.1 dislocations before revision surgery (range, 1 to 10). A primary traumatic dislocation occurred in 7 of 29 patients (24%); in all cases trauma was adequate for dislocation. Traumatic dislocation before recurrence was reported in 10 patients
Statistics All statistical analyses (odds ratio, standard error, confidence interval, and test of significance) were performed using SPSS software for Windows (version 22; SPSS, Chicago, IL). The P value was calculated according to Sheskin.23 No power analysis or sample size calculation was performed because of the limited number of patients.
Results Our review identified a total of 254 patients who underwent an arthroscopic stabilization procedure for anteroinferior glenohumeral instability, but preoperative MRI and/or CT scans were available for only 100 of these patients. Of the 254 included patients, 29 (11.4%) underwent a surgical revision procedure for recurrence of anteroinferior shoulder instability after the arthroscopic Bankart repair (Fig 3). Patient Demographic Characteristics and Risk Factors for Recurrence The 29 patients with recurrence of shoulder instability were evaluated (Table 1). Of these, 23 (79%) were
Fig 2. T2-weighted magnetic resonance image using a sagittal-plane view of the left shoulder. The measurement of the posterior radius of the glenoid and the measurement of the anteroinferior radius of the glenoid are obtained using this view. These values are then used to assess the glenoid track width. (The terms “Mittelwert” and “Abweichung” are automatically generated and have no significance in this case.)
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Fig 3. Flow diagram. (CT, computed tomography; MRI, magnetic resonance imaging.)
(34%). One recurrence of dislocation (3%) followed an epileptic episode. Surgery for recurrence of instability was performed within 2 years after initial arthroscopic Bankart repair in 10 patients (34%). The mean time from initial to revision surgery was 45.4 months (range, 7 to 136 months). Treatment for recurrence of instability was chosen individually based on trauma mechanism (traumatic or atraumatic), pathology (e.g., soft-tissue lesion or bony erosion or bony Bankart lesion close to anchor insertion), and number of redislocations. Arthroscopic management was the treatment performed in 9 patients (31%); an open Latarjet procedure, 19 (66%); and open capsuloplasty, 1 (3%). The initial number of anchors used for the arthroscopic repair was reported for 7 patients (24%). The mean number of anchors was 2.9 (range, 2 to 4 anchors). During revision surgery, 5 of the 9 patients undergoing arthroscopic revision stabilization (56%) reported the number of anchors used. The mean number of anchors was 3.7 (range, 3 to 4 anchors). Glenoid Track Measurements Preoperative CT and/or MRI scans were available for 100 of the 254 recruited patients. Advanced radiographic images were not available for the remaining 154 patients. Of the 100 patients with CT and/or MRI scans, 88 (88%) had an on-track Hill-Sachs lesion whereas the remaining 12 (12%) had an off-track
lesion. Revision surgery was required for recurrence of instability in 5 of 88 patients (6%) with an on-track Hill-Sachs lesion, whereas 4 of 12 patients (33%) with an off-track Hill-Sachs lesion required revision. Therefore, off-track Hill-Sachs lesions were associated with a significantly higher risk of recurrence (odds ratio, 8.3; 95% confidence interval, 1.85-37.26; P ¼ .006) (Fig 4).
Table 1. Patient Demographic Data and Risk Factors for Recurrence Data Male/female, n 23/6 Mean height (range), cm 177 (160-195) Mean body mass index 24.7 Mean age at time of initial surgery (range), yr 22.5 (9-37) Mean age at revision surgery (range), yr 27 (15-45) Patients with general hyperlaxity, n 2 of 29 (7%) Patients involved in sports, n 23 of 29 (79%) Patients with epilepsy, n 3 of 29 (10%) Mean number of dislocations before initial surgery 3.1 (1-5) (range) Mean number of dislocations before revision 2.1 (1-10) surgery (range) Mean number of anchors used for arthroscopic 2.9 (2-4) repair (range) Patients with traumatic dislocation before 10 recurrence, n Mean time from initial to revision surgery (range), 45.4 (7-136) mo
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Fig 4. Risk factors for recurrence of instability after arthroscopic Bankart repair expressed as a percentage of patients who required revision surgery for recurrence. (Alpsa, anterior labroligamentous periosteal sleeve avulsion.)
Discussion The most important result of this study is that an off-track Hill-Sachs lesion is a significant and important risk factor for recurrence of instability and need for revision surgery after arthroscopic Bankart repair when compared with an on-track Hill-Sachs lesion. The purpose of Bankart repair is to repair the labrum and retension the anteroinferior glenohumeral ligament to restore glenohumeral stability.24 Arthroscopic Bankart repair has shown good results for glenohumeral anteroinferior instability treatment, reaching similar results to open techniques.25 Nevertheless, the recurrence rate of instability and need for revision surgery are variable, with rates ranging from 3.9%10 to 49%.26 In this study 11.4% of patients with an arthroscopic Bankart repair needed revision for recurrence of instability. Patients’ risk factors for recurrence of instability, in combination with technical mistakes, can lead to higher rates of the need for revision surgery.11 Evaluating these factors is important to improve decision making for the treatment of this pathology. In the literature, the risk factors for recurrence of instability and need for revision surgery after arthroscopic Bankart repair are various. A significant negative correlation between redislocation after surgery and age at surgery has been found: at age 20 years or younger, the recurrence rate is 25%; at 21 to 30 years, it is 20%; and at 31 to 40 years, it is 7.1%.27 Male sex is another significant risk factor, with recurrence rates of 2.8% for female patients and 10.1% for male patients.2 The risk for patients with more than 1 dislocation after primary arthroscopic management increases according to the number of dislocations before surgery (1 to 2 dislocations, 11.1%; 3 to 5 dislocations, 17.8%; 6 to 10 dislocations, 43.3%; 11 to 21 dislocations, 43.4%; and >21 dislocations, 55.5%).17 In addition, patients with
hyperlaxity or ALPSA lesions (compared with Bankart lesions) have shown higher rates of recurrence, with rates of 18.9% for patients with lax ligaments compared with 4.9% for patients with no laxity (P ¼ .003) and rates of 12.6% for patients with ALPSA lesions compared with 6.5% for patients with Bankart lesions (P < .05).2 The association of recurrence and the type of sport in which the patient participated before surgery is unclear because an overhead sport activity might even reduce the risk of recurrence after arthroscopic repair.16 The role of glenoid bony lesions as a risk factor for recurrence is still unclear because different authors have shown an increase in risk of up to 61% if 25% to 30% or more of the glenoid is involved, whereas a recent systematic review found that the presence of a glenoid fracture with detachment of a bony fragment did not significantly increase the risk of failure after arthroscopic Bankart repair.2 Hill-Sachs lesion volume, instead, has shown a correlation with the risk of recurrence, with higher rates of recurrence for larger lesions.11,28 We found that patients with an off-track Hill-Sachs lesion had a much higher recurrence rate of instability and need for revision surgery than patients with an on-track Hill-Sachs lesion: 6% in the on-track group versus 33% in the off-track group (odds ratio, 8.3; 95% confidence interval, 1.85-37.26; P ¼ .006). Nevertheless, 67% of patients with an off-track lesion, even if treated without remplissage, as suggested by the treatment paradigm proposed by Di Giacomo et al.,19 did not require revision surgery. Besides, some patients with an on-track lesion required revision surgery for recurrence of instability. In this study we used preoperative MRI and/or CT scans to assess on- or off-track Hill-Sachs lesions. According to our experience and as recently suggested
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by Gyftopoulos et al.20 for MRI scans, we believe that these techniques can be used to accurately assess on- or off-track Hill-Sachs lesions. However, further evidence on the validity of these techniques to evaluate bipolar bone loss according to the glenoid track concept is warranted. Limitations Limitations of this study include the lack of availability of MRI and/or CT scans for all 254 patients and the retrospective nature of the study. There might also be a number of patients lost because we only evaluated our revisions. Strengths of the study are that a fully trained orthopaedic surgeon with a special interest in shoulder pathology performed all the measurements, all the surgical procedures were performed according to an identical procedure, and all surgeons were part of one team. In this study 11.4% of patients needed revision surgery for recurrence of instability. This rate may underestimate the problem because patients could have opted for treatment in other centers or may have chosen not to undergo further treatment for instability. In addition, more than half of the patients who needed a revision operation had already been treated surgically in other centers.
Conclusions An off-track Hill-Sachs lesion is a significant and important risk factor for recurrence of instability and need for revision surgery after arthroscopic Bankart repair when compared with an on-track Hill-Sachs lesion.
References 1. Longo UG, Loppini M, Berton A, Martinelli N, Maffulli N, Denaro V. Shoulder injuries in soccer players. Clin Cases Miner Bone Metab 2012;9:138-141. 2. Randelli P, Ragone V, Carminati S, Cabitza P. Risk factors for recurrence after Bankart repair a systematic review. Knee Surg Sports Traumatol Arthrosc 2012;20:2129-2138. 3. Longo UG, Rizzello G, Locher J, et al. Bone loss in patients with posterior gleno-humeral instability: A systematic review. Knee Surg Sports Traumatol Arthrosc 2016;24: 612-617. 4. Longo UG, Loppini M, Rizzello G, Ciuffreda M, Maffulli N, Denaro V. Management of primary acute anterior shoulder dislocation: Systematic review and quantitative synthesis of the literature. Arthroscopy 2014;30:506-522. 5. Bartl C, Salzmann GM, Seppel G, et al. Subscapularis function and structural integrity after arthroscopic repair of isolated subscapularis tears. Am J Sports Med 2011;39: 1255-1262. 6. Buchmann S, Brucker PU, Beitzel K, et al. Long-term effects on subscapularis integrity and function following arthroscopic shoulder stabilization with a low anteroinferior (5:30 o’clock) portal. Knee Surg Sports Traumatol Arthrosc 2015;24:422-429.
7. Kim S-H, Ha K-I, Kim S-H. Bankart repair in traumatic anterior shoulder instability. Arthroscopy 2002;18:755-763. 8. Thal R. Arthroscopic Bankart repair using knotless suture anchors. Arthroscopy 2007;23:566-567. 9. Sugaya H, Moriishi J, Kanisawa I, Tsuchiya A. Arthroscopic osseous Bankart repair for chronic recurrent traumatic anterior glenohumeral instability. J Bone Joint Surg Am 2005;87:1752-1760. 10. Hobby J, Griffin D, Dunbar M, Boileau P. Is arthroscopic surgery for stabilisation of chronic shoulder instability as effective as open surgery? A systematic review and metaanalysis of 62 studies including 3044 arthroscopic operations. J Bone Joint Surg Br 2007;89:1188-1196. 11. Voos JE, Livermore RW, Feeley BT, et al. Prospective evaluation of arthroscopic Bankart repairs for anterior instability. Am J Sports Med 2010;38:302-307. 12. Plath JE, Feucht MJ, Bangoj R, et al. Arthroscopic suture anchor fixation of bony Bankart lesions: Clinical outcome, magnetic resonance imaging results, and return to sports. Arthroscopy 2015;31:1472-1481. 13. 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;16:677-694. 14. Porcellini G, Campi F, Pegreffi F, Castagna A, Paladini P. Predisposing factors for recurrent shoulder dislocation after arthroscopic treatment. J Bone Joint Surg Am 2009;91: 2537-2542. 15. Flinkkilä T, Hyvönen P, Ohtonen P, Leppilahti J. Arthroscopic Bankart repair: Results and risk factors of recurrence of instability. Knee Surg Sports Traumatol Arthrosc 2010;18:1752-1758. 16. van der Linde JA, van Kampen DA, Terwee CB, Dijksman LM, Kleinjan G, Willems WJ. Long-term results after arthroscopic shoulder stabilization using suture anchors an 8- to 10-year follow-up. Am J Sports Med 2011;39:2396-2403. 17. Imhoff AB, Ansah P, Tischer T, et al. Arthroscopic repair of anterior-inferior glenohumeral instability using a portal at the 5:30-o’clock position: Analysis of the effects of age, fixation method, and concomitant shoulder injury on surgical outcomes. Am J Sports Med 2010;38:1795-1803. 18. Plath JE, Aboalata M, Seppel G, et al. Prevalence of and risk factors for dislocation arthropathy: Radiological longterm outcome of arthroscopic Bankart repair in 100 shoulders at an average 13-year follow-up. Am J Sports Med 2015;43:1084-1090. 19. Di Giacomo G, Itoi E, Burkhart SS. Evolving concept of bipolar bone loss and the Hill-Sachs lesion: From “engaging/non-engaging” lesion to “on-track/off-track” lesion. Arthroscopy 2014;30:90-98. 20. Gyftopoulos S, Beltran LS, Bookman J, Rokito A. MRI evaluation of bipolar bone loss using the on-track offtrack method: A feasibility study. AJR Am J Roentgenol 2015;205:848-852. 21. Yamamoto N, Itoi E, Abe H, et al. Contact between the glenoid and the humeral head in abduction, external rotation, and horizontal extension: A new concept of glenoid track. J Shoulder Elbow Surg 2007;16:649-656.
HILL-SACHS OFF-TRACK LESIONS 22. Itoi E, Yamamoto N, Kurokawa D, Sano H. Bone loss in anterior instability. Curr Rev Musculoskelet Med 2013;6: 88-94. 23. Sheskin DJ. Handbook of parametric and nonparametric statistical procedures. Boca Raton, FL: CRC Press, 2003. 24. Tischer T, Vogt S, Imhoff A. Arthroscopic stabilization of the shoulder with suture anchors with special reference to the deep anterior-inferior portal (5.30 o’clock). Oper Orthop Traumatol 2007;19:133-154 [in German]. 25. Petrera M, Patella V, Patella S, Theodoropoulos J. A metaanalysis of open versus arthroscopic Bankart repair using suture anchors. Knee Surg Sports Traumatol Arthrosc 2010;18:1742-1747.
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26. Pope EJ, Ward JP, Rokito AS. Anterior shoulder instabilitydA history of arthroscopic treatment. Bull NYU Hosp Jt Dis 2011;69:44-49. 27. Kandziora F, Jäger A, Bischof F, Herresthal J, Starker M, Mittlmeier T. Arthroscopic labrum refixation for posttraumatic anterior shoulder instability: Suture anchor versus transglenoid fixation technique. Arthroscopy 2000;16:359-366. 28. Longo UG, Loppini M, Rizzello G, et al. Remplissage, humeral osteochondral grafts, Weber osteotomy, and shoulder arthroplasty for the management of humeral bone defects in shoulder instability: Systematic review and quantitative synthesis of the literature. Arthroscopy 2014;30:1650-1666.
Purpose: To evaluate the effect of “off-track” Hill-Sachs lesions, according to the glenoid track concept, as a risk factor for recurrent instability and need for revision surgery after arthroscopic Bankart repair. Methods: We retrospectively reviewed 254 patients with anteroinferior glenohumeral instability who were managed with an arthroscopic stabilization procedure between 2006 and 2013. Preoperative magnetic resonance imaging and/or computed tomography scans were available for 100 of these patients to calculate the glenoid track and the presence of “on-track” or off-track Hill-Sachs lesions. Recurrence of instability was evaluated at a mean follow-up of 22.4 months. Results: Of 100 patients whose magnetic resonance imaging and/or computed tomography scans were available, 88 had an on-track Hill-Sachs lesion and 12 had an off-track Hill-Sachs lesion. Revision surgery for recurrent instability was performed in 5 patients (6%) with an on-track Hill-Sachs lesion and in 4 patients (33%) with an off-track Hill-Sachs lesion (odds ratio, 8.3; 95% confidence interval, 1.85-37.26; P ¼ .006). Conclusions: An off-track Hill-Sachs lesion is a significant and important risk factor for recurrence of instability and need for revision surgery after arthroscopic Bankart repair when compared with an on-track Hill-Sachs lesion. Level of Evidence: Level IV, prognostic case series.
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rthroscopic Bankart repair is recognized as a successful procedure to address glenohumeral instability.1-6 The outcome for anteroinferior instability after arthroscopic Bankart repair is comparable with open techniques, with instability recurrence rates of 3.4% to 19%.2,7-12 Potential risk factors for recurrence after arthroscopic Bankart repair include sex, young age at the time of first surgery, joint hyperlaxity, bilateral shoulder instability, number of dislocations, participation in collision sports, early return to contact sports, bone defects, technical errors, and anterior From the Department of Orthopaedic and Trauma Surgery, Campus Bio-Medico University (J.L., U.G.L., V.D.), Rome, Italy; and Department of Orthopaedic Sports Medicine, Klinikum rechts der Isar, Technische Universität München (J.L., F.W., K.B., S.B., A.B.I.), Munich, Germany. The authors report that they have no conflicts of interest in the authorship and publication of this article. Received August 11, 2015; accepted March 4, 2016. Address correspondence to Andreas B. Imhoff, M.D., Department of Orthopaedic Sports Medicine, Klinikum rechts der Isar, Technische Universität München, Ismaninger Street 22, 81675 Munich, Germany. E-mail: [email protected] Ó 2016 by the Arthroscopy Association of North America 0749-8063/15760/$36.00 http://dx.doi.org/10.1016/j.arthro.2016.03.005
labroligamentous periosteal sleeve avulsion (ALPSA) lesions.2,13-17 Osseous integrity is a critical component of bony stability. Proper imaging is important to guide clinical decision making.18 Recently, both radiographic and arthroscopic methods, using the concept of the glenoid track, have been developed to determine whether a Hill-Sachs lesion will engage the anterior glenoid rim.19,20 The glenoid track is described as the zone of contact between the glenoid and the superolateral portion of the humeral head, with the arm in abduction, external rotation, and horizontal extension.21 An engaging Hill-Sachs lesion is also called an “off-track” Hill-Sachs lesion; if the Hill-Sachs lesion does not engage, it is an “on-track” lesion. An intact glenoid track, without significant bone loss, guarantees bony stability of the shoulder.19,22 The aim of this study was to evaluate the role of offtrack and on-track Hill-Sachs lesions as a risk factor for recurrence of instability and need for revision surgery. We hypothesized that an off-track Hill-Sachs lesion would be a risk factor for recurrence of instability and need for revision surgery after arthroscopic Bankart repair.
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Methods We retrospectively reviewed clinical records of all patients managed at our center with an arthroscopic stabilization procedure between 2006 and 2013 because of anteroinferior glenohumeral instability. The exclusion criteria were glenoid bone loss greater than 25% or other unrelated sources of shoulder pain, including acromioclavicular joint arthritis, brachial plexus lesions, and glenohumeral arthritis. Patients with posterior or multidirectional instability were also excluded. Only patients with preoperative magnetic resonance imaging (MRI) and/or computed tomography (CT) scans were included. Recurrence of instability was evaluated at a mean follow-up of 22.4 months. Surgical Technique The surgical technique for arthroscopic stabilization with anchors has been described previously.17 The patient is placed in the beach-chair position under general anesthesia, and the type and direction of the instability are confirmed by clinical examination. Diagnostic arthroscopy is performed from a posterior portal. Next, the anterosuperior portal is placed anterior to the acromioclavicular joint, slightly medial to the long biceps tendon and close to the glenoid rim. The stability of the labrum and the biceps tendon anchor is assessed with a probe. For anteroinferior labral lesions, the anterior labrum is mobilized with an elevator. Decortication of the glenoid neck is performed until punctate bleeding occurs. Next, a deep anteroinferior portal is placed about 8 to 10 cm distal to the coracoid process and lateral to the axillary fold. Under arthroscopic visualization, a Wissinger rod is inserted through the lower third of the subscapularis and a long clear arthroscopy cannula is advanced. The first suture anchor is implanted at the 5:30eclock face position, at the bone-cartilage junction of the glenoid margin. The capsulolabral complex is pierced with a curved hollow suture passer (through the anteroinferior portal) from inferior toward the anchor so that the whole capsulolabral complex including the anteroinferior glenohumeral ligament is incorporated. A suture lasso is then passed through the hollow suture passer. The suture passer is removed, and the suture lasso together with a suture limb is retrieved out the anterosuperior portal. The suture limb is passed through the loop of the suture lasso, which is then retrieved out through the capsulolabral complex so that, finally, both suture limbs of the anchor come out the anteroinferior portal. The suture limb passing through the capsulolabral complex serves as a “post” over which the knot is tied. The labrum is fixed with an arthroscopic sliding knot. Two additional suture anchors are usually inserted at the 4:30eclock face position and 3-o’clock position in the same technique. Refixation of the capsulolabral complex, as well as the mobility, is confirmed by
passively moving the shoulder under arthroscopic visualization. One surgeon (A.B.I.) either performed or directed all surgical procedures. Postoperative Management The arm is immobilized in a sling for 24 hours. Use of the sling is continued at night for 4 weeks. Rehabilitation begins on postoperative day 1 under the direction of a trained physical therapist, focusing on rotator cuff strengthening and range of motion (45 of active abduction and flexion and 80 to 30 of active internal and external rotation in weeks 1 through 3; 90 of active abduction and flexion and 80 to 0 of active internal and external rotation in weeks 4 through 6; afterward, free range of motion is allowed). Free motion of the elbow and wrist is encouraged. The rehabilitation program lasts for approximately 6 months. If an accompanying SLAP lesion is present, no active biceps training is permitted for 6 weeks. Full overhead sporting activities are allowed after 6 months. On- or Off-track Hill-Sachs Lesion Evaluation The measurements were performed using a similar technique to calculate the glenoid track and the presence of on- or off-track Hill-Sachs lesions, using MRI scans, which was recently described by Gyftopoulos et al.20 Preoperative MRI and/or CT scans, available for 100 of the 254 patients who underwent an arthroscopic stabilization procedure at our center, were used to evaluate on- or off-track Hill-Sachs lesions. According to the description of Di Giacomo et al.,19 a Hill-Sachs lesion is off track, or engaging, if the Hill-Sachs interval is greater than the glenoid track width; otherwise, the Hill-Sachs lesion is on track, or non-engaging. The Hill-Sachs interval, as described by Di Giacomo et al.,19 is the distance from the rotator cuff attachments to the medial rim of the Hill-Sachs lesion, and it is equal to the width of the Hill-Sachs lesion plus the width of the intact bone bridge between the rotator cuff and the Hill-Sachs lesion. We used a transverse-plane view of the shoulder, in the slice with the largest extension of the Hill-Sachs lesion, and measured these 2 distances (Fig 1). The Hill-Sachs interval was then obtained using the formula of Di Giacomo et al.: Hill-Sachs interval ¼ Width of Hill-Sachs lesion þ Width of bone bridge. The glenoid track width, without a glenoid defect, is 83% of the glenoid width. If there is a bony defect of the glenoid (d), the distance d is subtracted from 83% of the glenoid width. Therefore, the glenoid track width in the face of glenoid bone loss (d) is equal to 0.83 D d, in which D is the inferior glenoid diameter. Initially, we placed a best-fit circle along the posterior and inferior margins of the glenoid. The diameter D was obtained by doubling the measurement of the posterior radius of the glenoid in a sagittal-plane view, whereas the value for bone loss (d) was obtained by subtracting
HILL-SACHS OFF-TRACK LESIONS
Fig 1. T2-weighted magnetic resonance image using a transverse-plane view of the left shoulder in the slice with the largest extension of the Hill-Sachs lesion. The Hill-Sachs interval is measured as the width of the Hill-Sachs lesion plus the width of the intact bone bridge between the rotator cuff and the Hill-Sachs lesion.
the measurement of the anteroinferior radius of the glenoid to the posterior radius (Fig 2). At this point, if the Hill-Sachs interval was greater than the glenoid track width, the Hill-Sachs lesion was off track, or engaging. If the Hill-Sachs interval was less than the glenoid track width, the Hill-Sachs lesion was on track, or non-engaging.19 All measurements were made by the same operator (J.L.), who was blinded to the patient’s history.
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male patients and 6 (21%) were female patients. The mean height was 177 cm (range, 160 to 195 cm), and the mean weight was 77.7 kg (range, 51 to 95 kg). The mean body mass index (BMI) value was 24.7; 15 patients had a normal or healthy weight (BMI, 18.5 to 25), whereas 8 were overweight (BMI, 25 to 30). The mean age at the time of initial surgery was 22.5 years (range, 9 to 37 years), and the mean age at revision surgery was 27 years (range, 15 to 45 years). The left shoulder was involved in 17 patients (59%) and the right in the remaining 12 (41%). Of the 29 patients, 23 (79%) were involved in sports. General hyperlaxity was reported by 2 patients (7%). In addition, 3 patients (10%) had epilepsy. A Hill-Sachs lesion was reported in 17 patients (59%) and a bony glenoid lesion was reported in 12 patients (41%) undergoing revision surgery for anteroinferior shoulder instability after arthroscopic Bankart repair. Both a Hill-Sachs lesion and a bony glenoid lesion were reported in 8 patients (28%). The size of the bony glenoid defect was always under 25% of the glenoid surface. A SLAP type V lesion was observed in 1 patient (3%). The number of dislocations before initial surgery was reported for 8 patients (28%). These patients had a mean of 3.1 dislocations before initial surgery (range, 1 to 5). The number of dislocations before revision surgery was reported for 15 patients (52%). These patients had a mean of 2.1 dislocations before revision surgery (range, 1 to 10). A primary traumatic dislocation occurred in 7 of 29 patients (24%); in all cases trauma was adequate for dislocation. Traumatic dislocation before recurrence was reported in 10 patients
Statistics All statistical analyses (odds ratio, standard error, confidence interval, and test of significance) were performed using SPSS software for Windows (version 22; SPSS, Chicago, IL). The P value was calculated according to Sheskin.23 No power analysis or sample size calculation was performed because of the limited number of patients.
Results Our review identified a total of 254 patients who underwent an arthroscopic stabilization procedure for anteroinferior glenohumeral instability, but preoperative MRI and/or CT scans were available for only 100 of these patients. Of the 254 included patients, 29 (11.4%) underwent a surgical revision procedure for recurrence of anteroinferior shoulder instability after the arthroscopic Bankart repair (Fig 3). Patient Demographic Characteristics and Risk Factors for Recurrence The 29 patients with recurrence of shoulder instability were evaluated (Table 1). Of these, 23 (79%) were
Fig 2. T2-weighted magnetic resonance image using a sagittal-plane view of the left shoulder. The measurement of the posterior radius of the glenoid and the measurement of the anteroinferior radius of the glenoid are obtained using this view. These values are then used to assess the glenoid track width. (The terms “Mittelwert” and “Abweichung” are automatically generated and have no significance in this case.)
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Fig 3. Flow diagram. (CT, computed tomography; MRI, magnetic resonance imaging.)
(34%). One recurrence of dislocation (3%) followed an epileptic episode. Surgery for recurrence of instability was performed within 2 years after initial arthroscopic Bankart repair in 10 patients (34%). The mean time from initial to revision surgery was 45.4 months (range, 7 to 136 months). Treatment for recurrence of instability was chosen individually based on trauma mechanism (traumatic or atraumatic), pathology (e.g., soft-tissue lesion or bony erosion or bony Bankart lesion close to anchor insertion), and number of redislocations. Arthroscopic management was the treatment performed in 9 patients (31%); an open Latarjet procedure, 19 (66%); and open capsuloplasty, 1 (3%). The initial number of anchors used for the arthroscopic repair was reported for 7 patients (24%). The mean number of anchors was 2.9 (range, 2 to 4 anchors). During revision surgery, 5 of the 9 patients undergoing arthroscopic revision stabilization (56%) reported the number of anchors used. The mean number of anchors was 3.7 (range, 3 to 4 anchors). Glenoid Track Measurements Preoperative CT and/or MRI scans were available for 100 of the 254 recruited patients. Advanced radiographic images were not available for the remaining 154 patients. Of the 100 patients with CT and/or MRI scans, 88 (88%) had an on-track Hill-Sachs lesion whereas the remaining 12 (12%) had an off-track
lesion. Revision surgery was required for recurrence of instability in 5 of 88 patients (6%) with an on-track Hill-Sachs lesion, whereas 4 of 12 patients (33%) with an off-track Hill-Sachs lesion required revision. Therefore, off-track Hill-Sachs lesions were associated with a significantly higher risk of recurrence (odds ratio, 8.3; 95% confidence interval, 1.85-37.26; P ¼ .006) (Fig 4).
Table 1. Patient Demographic Data and Risk Factors for Recurrence Data Male/female, n 23/6 Mean height (range), cm 177 (160-195) Mean body mass index 24.7 Mean age at time of initial surgery (range), yr 22.5 (9-37) Mean age at revision surgery (range), yr 27 (15-45) Patients with general hyperlaxity, n 2 of 29 (7%) Patients involved in sports, n 23 of 29 (79%) Patients with epilepsy, n 3 of 29 (10%) Mean number of dislocations before initial surgery 3.1 (1-5) (range) Mean number of dislocations before revision 2.1 (1-10) surgery (range) Mean number of anchors used for arthroscopic 2.9 (2-4) repair (range) Patients with traumatic dislocation before 10 recurrence, n Mean time from initial to revision surgery (range), 45.4 (7-136) mo
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Fig 4. Risk factors for recurrence of instability after arthroscopic Bankart repair expressed as a percentage of patients who required revision surgery for recurrence. (Alpsa, anterior labroligamentous periosteal sleeve avulsion.)
Discussion The most important result of this study is that an off-track Hill-Sachs lesion is a significant and important risk factor for recurrence of instability and need for revision surgery after arthroscopic Bankart repair when compared with an on-track Hill-Sachs lesion. The purpose of Bankart repair is to repair the labrum and retension the anteroinferior glenohumeral ligament to restore glenohumeral stability.24 Arthroscopic Bankart repair has shown good results for glenohumeral anteroinferior instability treatment, reaching similar results to open techniques.25 Nevertheless, the recurrence rate of instability and need for revision surgery are variable, with rates ranging from 3.9%10 to 49%.26 In this study 11.4% of patients with an arthroscopic Bankart repair needed revision for recurrence of instability. Patients’ risk factors for recurrence of instability, in combination with technical mistakes, can lead to higher rates of the need for revision surgery.11 Evaluating these factors is important to improve decision making for the treatment of this pathology. In the literature, the risk factors for recurrence of instability and need for revision surgery after arthroscopic Bankart repair are various. A significant negative correlation between redislocation after surgery and age at surgery has been found: at age 20 years or younger, the recurrence rate is 25%; at 21 to 30 years, it is 20%; and at 31 to 40 years, it is 7.1%.27 Male sex is another significant risk factor, with recurrence rates of 2.8% for female patients and 10.1% for male patients.2 The risk for patients with more than 1 dislocation after primary arthroscopic management increases according to the number of dislocations before surgery (1 to 2 dislocations, 11.1%; 3 to 5 dislocations, 17.8%; 6 to 10 dislocations, 43.3%; 11 to 21 dislocations, 43.4%; and >21 dislocations, 55.5%).17 In addition, patients with
hyperlaxity or ALPSA lesions (compared with Bankart lesions) have shown higher rates of recurrence, with rates of 18.9% for patients with lax ligaments compared with 4.9% for patients with no laxity (P ¼ .003) and rates of 12.6% for patients with ALPSA lesions compared with 6.5% for patients with Bankart lesions (P < .05).2 The association of recurrence and the type of sport in which the patient participated before surgery is unclear because an overhead sport activity might even reduce the risk of recurrence after arthroscopic repair.16 The role of glenoid bony lesions as a risk factor for recurrence is still unclear because different authors have shown an increase in risk of up to 61% if 25% to 30% or more of the glenoid is involved, whereas a recent systematic review found that the presence of a glenoid fracture with detachment of a bony fragment did not significantly increase the risk of failure after arthroscopic Bankart repair.2 Hill-Sachs lesion volume, instead, has shown a correlation with the risk of recurrence, with higher rates of recurrence for larger lesions.11,28 We found that patients with an off-track Hill-Sachs lesion had a much higher recurrence rate of instability and need for revision surgery than patients with an on-track Hill-Sachs lesion: 6% in the on-track group versus 33% in the off-track group (odds ratio, 8.3; 95% confidence interval, 1.85-37.26; P ¼ .006). Nevertheless, 67% of patients with an off-track lesion, even if treated without remplissage, as suggested by the treatment paradigm proposed by Di Giacomo et al.,19 did not require revision surgery. Besides, some patients with an on-track lesion required revision surgery for recurrence of instability. In this study we used preoperative MRI and/or CT scans to assess on- or off-track Hill-Sachs lesions. According to our experience and as recently suggested
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by Gyftopoulos et al.20 for MRI scans, we believe that these techniques can be used to accurately assess on- or off-track Hill-Sachs lesions. However, further evidence on the validity of these techniques to evaluate bipolar bone loss according to the glenoid track concept is warranted. Limitations Limitations of this study include the lack of availability of MRI and/or CT scans for all 254 patients and the retrospective nature of the study. There might also be a number of patients lost because we only evaluated our revisions. Strengths of the study are that a fully trained orthopaedic surgeon with a special interest in shoulder pathology performed all the measurements, all the surgical procedures were performed according to an identical procedure, and all surgeons were part of one team. In this study 11.4% of patients needed revision surgery for recurrence of instability. This rate may underestimate the problem because patients could have opted for treatment in other centers or may have chosen not to undergo further treatment for instability. In addition, more than half of the patients who needed a revision operation had already been treated surgically in other centers.
Conclusions An off-track Hill-Sachs lesion is a significant and important risk factor for recurrence of instability and need for revision surgery after arthroscopic Bankart repair when compared with an on-track Hill-Sachs lesion.
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26. Pope EJ, Ward JP, Rokito AS. Anterior shoulder instabilitydA history of arthroscopic treatment. Bull NYU Hosp Jt Dis 2011;69:44-49. 27. Kandziora F, Jäger A, Bischof F, Herresthal J, Starker M, Mittlmeier T. Arthroscopic labrum refixation for posttraumatic anterior shoulder instability: Suture anchor versus transglenoid fixation technique. Arthroscopy 2000;16:359-366. 28. Longo UG, Loppini M, Rizzello G, et al. Remplissage, humeral osteochondral grafts, Weber osteotomy, and shoulder arthroplasty for the management of humeral bone defects in shoulder instability: Systematic review and quantitative synthesis of the literature. Arthroscopy 2014;30:1650-1666.