
==== Front
JSES Int
JSES Int
JSES International
2666-6383
Elsevier

S2666-6383(24)00156-7
10.1016/j.jseint.2024.06.008
Shoulder
Shoulder Trauma
Single anterior shoulder dislocation patients demonstrate higher rates of posterior labral repair and biceps procedures than multiple dislocators at the time of arthroscopic stabilization surgery
Wilde Brandon BS
Clinker Christopher BS
Da Silva Adrik BS
McNamara Natalya MD
Simister Samuel MD, MBA
Chalmers Peter N. MD
Ernat Justin MD, MHA Ernat.research@hsc.utah.edu
∗
Department of Orthopaedic Surgery, University of Utah, Salt Lake City, UT, USA
∗ Corresponding author: Justin Ernat, MD, MHA, Department of Orthopaedic Surgery, University of Utah, 590 Wakara Way, Salt Lake City, UT, USA. Ernat.research@hsc.utah.edu
03 7 2024
9 2024
03 7 2024
8 5 978983
© 2024 The Authors
2024
https://creativecommons.org/licenses/by-nc-nd/4.0/ This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Hypothesis

The purpose of this study is to identify and compare demographic, clinical, historical, and intraoperative variables in patients who have received arthroscopic treatment for single vs. multiple anterior shoulder dislocations.

Methods

This is a retrospective chart review of patients who underwent arthroscopic labral repair of the shoulder by six surgeons at a single institution between 2012 and 2020. Patients with a documented anterior shoulder dislocation were included. Patients with pain-only, subluxation-only, multidirectional or posterior instability, and prior shoulder surgeries of any kind were excluded. Studied variables included age, sex, laterality, body mass index, contact/collision sports, Charlson comorbidity index, tobacco use, number of dislocations (1, >1), labral tear size, time from first dislocation to surgery, anchor number, and concomitant procedures. Study groups were compared using student’s t-tests and Mann-Whitney U test for continuous variables and chi-square or Fisher’s exact tests for discrete variables with a significance of 0.05.

Results

Six hundred thirty-three patients were identified, and 351 (85 single dislocators [SDs], 266 multiple dislocators [MDs]) met inclusion criteria (mean age: 27 years; range: 14-71 years). There were no demographic differences between the study groups. SD received surgery significantly sooner at 17 ± 44 months after injury, while MD received surgery 53 ± 74 months postinitial dislocation. SDs (30/85, 35%) were significantly more likely than MDs (56/266, 21%) to receive concomitant posterior labrum repair. MDs (46/266, 17%) were significantly more likely than SDs (5/85, 6%) to receive a remplissage. SDs (11/85, 13%) were significantly more likely than MDs (11/266, 4%) to receive a concomitant biceps tenotomy/tenodesis. There were no other significant differences in injury or surgery characteristics.

Conclusion

MDs will have more time between their initial dislocation and arthroscopic labral repair and are more likely to receive a remplissage procedure, yet they are less likely than SDs to receive a concomitant posterior labral repair or biceps tenodesis/tenotomy despite no differences in age, sex, and activity level. Whether the greater extent of labrum injury in SD is due to a more severe initial injury vs. earlier recognition and intervention requires further study.

Keywords

Shoulder dislocation
Anterior shoulder instability
Arthroscopic labral repair
Labrum
Labral tear
Remplissage
==== Body
pmcShoulder dislocations account for approximately 50% of all joint dislocations, making them the most commonly dislocated joint in the body.9,15,26,31,54 The estimated lifetime incidence rate of shoulder dislocation is nearly 24 per 100,000 person-years in the United States.64 Of these, anterior dislocations are more common than posterior dislocations.1,19,32,40,43,50,52,57,64 The risk factors for recurrence and failure of operative intervention have been extensively studied in anterior shoulder instability cohorts. These have included young age, male sex, contact athletes, and the presence of humeral or glenoid bone loss, among others.5,22,32,43,44,50,54,64 In lieu of this, the optimal approach for a patient with anterior shoulder instability remains debatable due to several factors. These include potentially unsatisfactory outcomes of conservative treatment, high rates of recurrence despite surgical repair, and a lack of appropriate dissemination and implementation of evidence-based medicine regarding first-time anterior dislocations.1,3,12,21,36,37,42,45,51 The optimal approach is further complicated in that, until more recently, much of the evidence on outcomes has historically failed to delineate between those who have sustained a single anterior shoulder dislocation compared to those who have experienced multiple dislocations.

Traditionally, initial management of anterior shoulder dislocations proceeded with a trial of nonoperative treatment followed by surgical repair if the nonoperative protocol failed.62 More recently, there has been an increasing amount of literature suggesting that surgical intervention following a first-time anterior dislocation is favored in several patient populations.1,4,8,11,16,40,41 These findings are contrasted against other studies suggesting comparable outcomes between anterior dislocation patients treated conservatively and those treated surgically.61,63 Furthermore, much of the controversy surrounding optimal management for first-time anterior dislocations arises from uncertainty regarding long-term outcomes and risk of recurrence even after surgical repair. For example, several studies support initial Bankart repair surgery over conservative management to address high rates of residual instability following first-time anterior shoulder dislocations.35 However, long-term outcomes following Bankart repair vary significantly. Long-term outcomes following Bankart repair in a meta-analysis by Hurley et al reported a recurrence rate of instability of 9.7% compared to a rate of 67.4% following conservative treatment.35 Other studies conducted by Chahal et al,14 Eren et al,24 Porcellini et al,51 and Alkhatib et al3 have shown comparable rates of recurrence. These are contrasted to long-term outcomes observed in a systematic review by Murphy et al. This review showed redislocation following Bankart repair recurred at a rate of 16.0%—although these results were not restricted to Bankart repairs only.49 Additionally, 59.4% of patients showed evidence of arthropathy following surgical repair. The results of these studies continue the debate as to whether operative management is the best strategy for first-time anterior shoulder dislocations.

The major concern about conservative treatment of anterior shoulder dislocations is the relatively high rates of recurrent instability and potential negative implications of such on glenohumeral bone quality. However, labral repair of multiple dislocators is also not without its complications.1,11,33,34,55 The failure rates of arthroscopic stabilization of recurrent traumatic anterior instability of the shoulder range between 4% and 21%.17,30,47,51,58

Given these concerns and controversies presented above, recent studies have attempted to compare and contrast the risk factors, surgical approaches, and outcomes of single anterior shoulder dislocations and multiple dislocations separately. However, robust data with direct comparisons of the two groups regarding demographics, instability history, and surgery characteristics are lacking.7,27,38,48 Therefore, the purpose of this study is to identify and compare demographic, clinical, and perioperative variables in patients receiving arthroscopic treatment for single vs. multiple anterior shoulder dislocations. We hypothesize that patients with single dislocations will have received intervention in a timelier fashion from their injury, and those with multiple dislocations will be more likely to have concomitant pathology/procedures (in addition to the anterior labral tear) at the time of anterior labral repair.

Methods

This single-center study was approved by the institutional review board. A retrospective chart review was performed for consecutive patients who underwent arthroscopic labral repair surgery by six surgeons for anterior shoulder instability between 2012 and 2020. The electronic medical records were reviewed for demographic data, injury data, instability history, activity level, and comorbidities. Operative reports were reviewed to confirm tear size, implant usage, and concomitant procedures. Only patients with a history of anterior dislocation that received an arthroscopic surgical repair were included. Exclusion criteria were patients without a true dislocation event (ie, subluxation or pain-only on presentation), a primary diagnosis of multidirectional instability or posterior instability, and prior shoulder surgeries of any kind. Demographics and operative variables included age, sex, laterality, body mass index, participation in contact/collision sports, Charlson comorbidity index, tobacco use, number of full dislocations (1, >1), time from first dislocation to surgery, number of anchors used for repair, and concomitant procedures performed.

Statistical analysis

All analyses were conducted in Excel 16 (Microsoft, Redmond, WA, USA) and SPSS 29 (IBM Corp., Armonk, NY, USA). Data were analyzed for normality using the Kolmogorov-Smirnov test, and parametric and nonparametric tests were used as appropriate depending upon data normality. Categorical data were compared between groups using chi-square tests and Fisher’s exact tests depending on cell populations. Continuous data were compared between groups using Student’s t-tests and Mann-Whitney U tests as appropriate depending on data normality. After the exclusion of multidirectional instability patients and revision surgeries, we compared patients with a singular anterior dislocation event to those with multiple anterior dislocation events. Two-tailed tests were performed in all cases, and P values of < .05 were considered significant.

Results

Six hundred thirty-three (633) patients were identified as having received an arthroscopic labral repair. Of the patients, 351/633 (55.5%) met inclusion criteria including single dislocators (SDs) (85/351, 24.2%) and multiple dislocators (MDs) (266/351, 75.8%). There were no statistically significant differences in the demographics variables between the two groups including age at surgery, sex, laterality, involvement with contact/collision sports, body mass index, Charlson comorbidity index, and tobacco use (Table 1). In the SD group, the time from dislocation to surgery was 17 ± 44 months compared to the MD group, where the time from first dislocation to surgery was 53 ± 74 months (P < .001).Table I Demographics and instability histories comparing those with a single dislocation to those with multiple dislocations, excluding multidirectional instability and posterior instability and only including those with a full dislocation.

Type	Variable	First-time dislocators	Recurrent dislocators	P value	
Demographics	Age at surgery (yr)	28 ± 11	26 ± 10	.588	
Male	80% (68/85)	75% (199/266)	.329	
Right side	56% (42/75)	57% (138/243)	.904	
Contact/collision athlete	37% (31/85)	48% (128/266)	.060	
Body mass index (BMI)	26 ± 5	26 ± 6	.475	
Charlson comorbidity index (CCI)	0 ± 0	0 ± 1	.391	
Tobacco use	12% (10/85)	17% (44/266)	.288	
Instability history	Time from first dislocation to surgery (mo)	17 ± 44	53 ± 74	<.001	
Categorical variables are shown as % (N), and continuous variables are shown as mean ± standard deviation. Significant differences are bolded.

Thirty-five percent (30/85) of the patients in the SD group had a concomitant posterior labral repair in addition to their anterior repair, compared to 21% (56/266) of the MD group (P < .008). The SD group was also more likely to receive a concomitant biceps procedure (tenodesis or tenotomy) (11/85, 13%) than the MD group (11/266, 4%) (P < .004). Seventeen percent (46/266) of the MD patients received a remplissage procedure, whereas 6% (5/85) of the SD patients received a remplissage procedure (P < .009). Other concomitant procedures including superior labral repair, 360-degree labral repair, number of anchors, capsular plication, humeral avulsion of the glenohumeral ligament repair, subacromial decompression, rotator cuff repair, and distal clavicle excision were not statistically significant between the two groups (Table 2).Table II Surgical characteristics comparing those with a single dislocation to those with multiple dislocations, excluding multidirectional instability and posterior instability and only including those with a full dislocation.

Type	Single dislocators	Multiple dislocators	P value	
Surgical characteristics				
 Posterior repair	35% (30/85)	21% (56/266)	.008	
 Superior repair	7% (6/85)	10% (27/266)	.395	
 360° repair	1% (1/85)	3% (8/266)	.352	
 Number of anchors	4 ± 1	4 ± 1	.067	
 Capsular plication	37% (31/85)	44% (117/266)	.222	
 HAGL repair	5% (4/85)	2% (4/266)	.101	
 Remplissage	6% (5/85)	17% (46/266)	.009	
 Subacromial decompression	4% (3/85)	1% (3/266)	.137	
 Rotator cuff repair	5% (4/85)	3% (7/266)	.339	
 Distal clavicle excision	1% (1/85)	0% (1/266)	.393	
 Biceps tenodesis/tenotomy	13% (11/85)	4% (11/266)	.004	
HAGL, humeral avulsion of the glenohumeral ligament.

Categorical variables are shown as % (N), and continuous variables are shown as mean ± standard deviation. Significant differences are bolded.

Discussion

In this review of 351 patients, we identified and compared the demographics, instability histories, and surgical characteristics of arthroscopic stabilization surgery after a history of single or multiple anterior shoulder dislocations. The most critical findings of this study were that patients with multiple anterior shoulder dislocations will have more time between their first dislocation and arthroscopic labral repair and more often receive a remplissage, yet multiple dislocators are less likely to have concomitant procedures such as posterior labral repair or biceps tenodesis/tenotomy. Thus, our hypothesis was only partially confirmed as it pertains to surgical timing, and the postulation that multiple dislocators would have more concomitant pathology was rejected.

In this series, the time between the initial anterior shoulder dislocation and surgery is nearly three times as long for those who suffered multiple dislocations compared to those with only a single dislocation (approximately 4.5 years vs. 1.5 years, respectively). Other studies have reported remarkably variable time intervals between the initial dislocation and surgical intervention among diverse patient cohorts. For example, a prospective study by Habermeyer et al reported mean preoperative histories for patients with a single dislocation at 0.8 months, 1-3 dislocations at 29.1 months, 4-6 dislocations at 48.9 months, and >6 dislocations at 79.3 months.29 Kim et al reported shorter intervals of 14.2 days and 25.3 months for single dislocation and recurrent (>1) dislocation groups, respectively.38 Lastly, a systematic review comparing surgical outcomes after primary vs. recurrent anterior shoulder instability of level I and level II studies by Barlow et al showed time intervals from first dislocation to surgery as short as 5 days for a single dislocation and as long as 6.4 years for recurrent (>1) dislocation.7 Our finding in the context of the vast range of times to surgery reported in other studies could correlate with the controversy that remains about optimal management for single and recurrent anterior shoulder dislocations, which begins with the decision to proceed with operative or nonoperative treatment. Electing between operative and nonoperative management for first-time anterior shoulder dislocation largely consists of deliberating the lower risk of another dislocation against the cost and the longer initial recovery associated with surgery.18,36,60 However, how to go about weighing the risk of another dislocation often convolutes the shared decision-making process between a patient and surgeon, as the specific risk varies widely from 10% to 90%.59

Further compounding the debate surrounding optimal management follows a recent study by the Hutyra et al group, who found that patients with first-time dislocations often receive insufficient information to decide about their management. Namely, a large number of patients—50% out of 1755—with a first-time anterior shoulder dislocation fail to follow up with appropriate specialized care providers or receive evidence-based care recommendations. Critical findings from that study worth noting include physician estimates of the risk of redislocation within a 2-year window aligned with medical evidence 59% of the time. Moreover, only 29% of patients obtained information for first-time anterior shoulder dislocation that aligns with high-level medical evidence. We speculate that the lack of shared evidence-based medicine and follow-up with a healthcare provider could further explain the differences in time to surgery for single and recurrent shoulder dislocations. Further research is needed in that regard.

Interestingly, in our study, 13% of patients with single dislocations also had a biceps procedure, as compared to 4% of >1 dislocations. We speculate that this could be for one or several reasons. First, one possible explanation is that single dislocation patients were selected for surgery because dislocation occurred secondary to a higher energy mechanism, and this possibly resulted in a greater degree of labral pathology and resultant need for concomitant procedures, including posterior labral repairs and biceps tenodesis/tenotomy. This, in turn, could prompt a surgeon to be more likely to recommend surgery after a single dislocation—an inherent selection bias of this study. Other dislocation literature may have more insight into this finding. For example, Eichinger et al found in a cadaveric study that anterior-inferior dislocation direction requires less energy for a dislocation and less risk for associated pathology than a direct anterior dislocation.23 Another related consideration, while highly speculative and especially vulnerable to selection bias, is the difference in the prevalence of superior labrum anterior-to-posterior (SLAP) lesions between single dislocations and the recurrent dislocation group. Biceps tenodesis is a viable option for SLAP tears in many cases, with some arguing that it has better or comparable outcomes than SLAP lesion repair.10,20 A higher prevalence of SLAP lesions in the single dislocations group would likely explain the higher rate of biceps procedures. A 2023 study by Eren et al found that the prevalence of SLAP lesions was higher in a primary instability group compared to a recurrent instability group—43.9% and 28.6%, respectively. They postulated that early intervention with surgery in patients with primary instability may lead to early detection of a SLAP lesion.25 Recurrent instability may also be more associated with III and IV SLAP lesions that usually do not require a biceps procedure. A 2010 study by Kim et al found that patients with recurrent dislocations were more likely to have type III and IV SLAP lesions compared to primary dislocators.38

Our study also found that 35% of those with a single dislocation also had a posterior labrum repair, whereas 21% of those with >1 dislocation had an accompanying posterior labrum repair. Our findings are opposed to a level II prognostic study by Gutierrez et al, who showed that 36% (16/45) of patients with single anterior dislocations had a posterior labral tear compared to 47% (24/51) of patients with recurrent (>1) dislocations.28 Moreover, Baker et al saw posterior labral pathology in 24% (11/45) of patients with first-time anterior shoulder dislocations.6 Given that primary instability is associated with change in the glenohumeral joint, subsequent dislocations are often possible after lower energy mechanisms than a primary dislocation.53 These findings are in line with our previous discussion/speculation that patients with single dislocations could correlate with a more significant amount of energy/mechanism during their dislocation event compared to patients with recurrent dislocations. Specifically, a more significant amount of energy/mechanism could explain why patients with a single dislocation had a higher likelihood of posterior labral tear and subsequent repair compared to patients with >1 dislocation in our study cohort. Although, admittedly, these are also potentially limited by selection bias.

While patients with a single dislocation had higher rates of both biceps procedures and posterior labral repairs, patients with recurrent dislocations had higher rates of remplissage procedures than did the single dislocation group. These results follow that there is higher prevalence of clinically significant Hill-Sachs lesions in recurrent dislocations compared to single dislocations.13,39,56 There have been several proposed surgical approaches to treat a Hill-Sachs bone defect following anterior shoulder dislocation and remplissage procedure is among the most common.13 There is also a considerable amount of research suggesting remplissage and Bankart repair are superior to Bankart repair alone in patients with anterior shoulder dislocations with accompanying Hill-Sachs lesions.2,13,35,46 Specifically, a meta-analysis by Camus et al in 2018 showed that combined Bankart repair and remplissage decreased rates of recurrent instability (defined as redislocation only) by 4-fold compared to isolated Bankart repair in patients with anterior shoulder dislocation.13

This study has several limitations. This is a retrospective case study. The sample size is limited, although 351 consecutive patients is one of the largest single-institutional studies to date. This dataset reflects the practices of the six surgeons and may not be generalizable to other settings. Additionally, the surgeon selection bias is inherent to the concomitant procedures reported and the decision-making involved regarding such procedures. There is also a selection bias as to who went into arthroscopic surgery as compared to nonoperative treatment or an open procedure. We did not stratify patients based on mechanism of primary dislocation event, thus obscuring correlations of time intervals to surgery and concomitant procedures performed. Furthermore, we did not record and compare differences in pathology type (ie, anterior labrum periosteal sleeve avulsion lesions, Hill-Sachs lesions, etc.) or pathology characteristics (eg, labrum tear size) identified before surgery between the single dislocation group and the multiple dislocation group. There is also no data explaining the time interval between initial dislocation and surgery, such as delayed presentation of symptoms, an initial trial of conservative management/therapy, and time between the initial evaluation with the orthopedic surgeon and ultimate surgery. Moreover, we categorized patients into 1 or >1 dislocations and did not further categorize number of dislocations into >2, >3, etc. Lastly, within this study, we did not delineate the specific types of contact sports the patients were engaged in, which assumes similar mechanisms of stress that are not generalizable to all contact athletes. Future studies are planned in that regard.

Conclusion

Multiple anterior dislocation patients who received arthroscopic anterior labral repair had more time between their initial dislocation and repair and were more likely to receive a remplissage procedure, yet were less likely than single anterior dislocators to receive a concomitant posterior labral repair or biceps tenodesis/tenotomy despite no differences in age, sex, and activity level. Whether the greater extent of labrum injury in single dislocators is due to a more severe initial injury vs. earlier recognition and intervention requires further study.

Disclaimers:

Funding: No funding was disclosed by the authors.

Conflicts of interest: Justin Ernat is a paid consultant for Depuy Mitek Sports Medicine, is an editorial board member for Arthroscopy, and is a committee member for the Arthroscopy Association of North America and the American Orthopaedic Society for Sports Medicine. Peter Chalmers is a paid consultant for Exactech, Depuy, and DJO, serves on the editorial board for the Journal of Shoulder and Elbow Surgery, receives intellectual property royalties from Depuy and Responsive, and has equity in TitinKM. The other authors, their immediate families, and any research foundations with which they are affiliated have not received any financial payments or other benefits from any commercial entity related to the subject of this article.

This study was performed under (1) the University of Utah Institutional Review Board as approved protocol #00169833. Each author certifies that his or her institution approved the human protocol for this investigation, that all investigations were conducted in conformity with ethical principles of research, and that informed consent for participation in the study was not required by the authors’ institutional review board.

The work for this manuscript was performed at the University of Utah.
==== Refs
References

1 Adam M. Attia A.K. Alhammoud A. Aldahamsheh O. Al Ateeq Al Dosari M. Ahmed G. Arthroscopic Bankart repair for the acute anterior shoulder dislocation: systematic review and meta-analysis Int Orthop 42 2018 2413 2422 10.1007/s00264-018-4046-0 29982868
2 Alkaduhimi H. Verweij L.P.E. Willigenburg N.W. Van Deurzen D.F.P. Van Den Bekerom M.P.J. Remplissage with Bankart repair in anterior shoulder instability: a systematic review of the clinical and cadaveric literature Arthrosc J Arthrosc Relat Surg 35 2019 1257 1266 10.1016/j.arthro.2018.10.117
3 Alkhatib N. Abdullah A.S.A. AlNouri M. Ahmad Alzobi O.Z. Alkaramany E. Ishibashi Y. Short- and long-term outcomes in Bankart repair vs. conservative treatment for first-time anterior shoulder dislocation: a systematic review and meta-analysis of randomized controlled trials J Shoulder Elbow Surg 31 2022 1751 1762 10.1016/j.jse.2022.02.032 35398165
4 Arciero R.A. Wheeler J.H. Ryan J.B. McBride J.T. Arthroscopic Bankart repair versus nonoperative treatment for acute, initial anterior shoulder dislocations Am J Sports Med 22 1994 589 594 7810780
5 Arner J.W. Peebles L.A. Bradley J.P. Provencher M.T. Anterior shoulder instability management: indications, techniques, and outcomes Arthrosc J Arthrosc Relat Surg 36 2020 2791 2793 10.1016/j.arthro.2020.09.024
6 Baker C.L. Uribe J.W. Whitman C. Arthroscopic evaluation of acute initial anterior shoulder dislocations Am J Sports Med 18 1990 25 28 2301687
7 Barlow J.D. Grosel T. Higgins J. Everhart J.S. Magnussen R.A. Surgical treatment outcomes after primary vs recurrent anterior shoulder instability J Clin Orthop Trauma 10 2019 222 230 10.1016/j.jcot.2018.10.012 30828182
8 Belk J.W. Wharton B.R. Houck D.A. Bravman J.T. Kraeutler M.J. Mayer B. Shoulder stabilization versus immobilization for first-time anterior shoulder dislocation: a systematic review and meta-analysis of level 1 randomized controlled trials Am J Sports Med 51 2023 1634 1643 10.1177/03635465211065403 35148222
9 Bernard C.D. Leland D.P. Keyt L.K. LaPrade M.D. Krych A.J. Dahm D.L. Although surgical techniques differ, similar outcomes can be obtained when operating after single versus multiple anterior shoulder dislocations Arthrosc Sports Med Rehabil 3 2021 e163 e170 10.1016/j.asmr.2020.09.006 33615260
10 Boileau P. Parratte S. Chuinard C. Roussanne Y. Shia D. Bicknell R. Arthroscopic treatment of isolated type II SLAP lesions: biceps tenodesis as an alternative to reinsertion Am J Sports Med 37 2009 929 936 10.1177/0363546508330127 19229046
11 Bottoni C.R. Wilckens J.H. DeBerardino T.M. D’Alleyrand J.-C.G. Rooney R.C. Harpstrite J.K. A prospective, randomized evaluation of arthroscopic stabilization versus nonoperative treatment in patients with acute, traumatic, first-time shoulder dislocations Am J Sports Med 30 2002 576 580 10.1177/03635465020300041801 12130413
12 Burkhart S.S. De Beer J.F. Traumatic glenohumeral bone defects and their relationship to failure of arthroscopic Bankart repairs Arthrosc J Arthrosc Relat Surg 16 2000 677 694
13 Camus D. Domos P. Berard E. Toulemonde J. Mansat P. Bonnevialle N. Isolated arthroscopic Bankart repair vs. Bankart repair with “remplissage” for anterior shoulder instability with engaging Hill-Sachs lesion: a meta-analysis J Orthop Traumatol Surg Res 104 2018 803 809 10.1016/j.otsr.2018.05.011
14 Chahal J. Marks P.H. MacDonald P.B. Shah P.S. Theodoropoulos J. Ravi B. Anatomic Bankart repair compared with nonoperative treatment and/or arthroscopic lavage for first-time traumatic shoulder dislocation Arthrosc J Arthrosc Relat Surg 28 2012 565 575 10.1016/j.arthro.2011.11.012
15 Chan A.G. Kilcoyne K.G. Chan S. Dickens J.F. Waterman B.R. Evaluation of the Instability Severity Index score in predicting failure following arthroscopic Bankart surgery in an active military population J Shoulder Elbow Surg 28 2019 e156 e163 10.1016/j.jse.2018.11.048 30685274
16 Chapus V. Rochcongar G. Pineau V. Salle De Chou É. Hulet C. Ten-year follow-up of acute arthroscopic Bankart repair for initial anterior shoulder dislocation in young patients J Orthop Traumatol Surg Res 101 2015 889 893 10.1016/j.otsr.2015.09.029
17 Cole B.J. Lʼinsalata J. Irrgang J. Warner J.J.P. Comparison of arthroscopic and open anterior shoulder stabilization: a two to six-year follow-up study J Bone Joint Surg Am 82 2000 1108 1114 10954100
18 Crall T.S. Bishop J.A. Guttman D. Kocher M. Bozic K. Lubowitz J.H. Cost-Effectiveness analysis of primary arthroscopic stabilization versus nonoperative treatment for first-time anterior glenohumeral dislocations Arthrosc J Arthrosc Relat Surg 28 2012 1755 1765 10.1016/j.arthro.2012.05.885
19 DeFroda S.F. Donnelly J.C. Mulcahey M.K. Perez L. Owens B.D. Shoulder instability in women compared with men: epidemiology, pathophysiology, and special considerations JBJS Rev 7 2019 e10 10.2106/JBJS.RVW.19.00007
20 Denard P.J. Lädermann A. Parsley B.K. Burkhart S.S. Arthroscopic biceps tenodesis compared with repair of isolated type II SLAP lesions in patients older than 35 years Orthopedics 37 2014 e292 e297 10.3928/01477447-20140225-63 24762158
21 Dickens J.F. Owens B.D. Cameron K.L. Kilcoyne K. Allred C.D. Svoboda S.J. Return to play and recurrent instability after in-season anterior shoulder instability: a prospective multicenter study Am J Sports Med 42 2014 2842 2850 10.1177/0363546514553181 25378207
22 Dumont G.D. Russell R.D. Robertson W.J. Anterior shoulder instability: a review of pathoanatomy, diagnosis and treatment Curr Rev Musculoskelet Med 4 2011 200 207 10.1007/s12178-011-9092-9 21808996
23 Eichinger J.K. Massimini D.F. Kim J. Higgins L.D. Biomechanical evaluation of glenoid version and dislocation direction on the influence of anterior shoulder instability and development of hill-sachs lesions Am J Sports Med 44 2016 2792 2799 10.1177/0363546516659281 27496904
24 Eren İ. Büyükdogan K. Yürük B. Aslan L. Birsel O. Demirhan M. Patients without re-dislocation in the short term after arthroscopic knotless Bankart repair for anterior shoulder instability may show residual apprehension and recurrence in the long term after 5 years J Shoulder Elbow Surg 31 2022 978 983 10.1016/j.jse.2021.10.042 34871729
25 Eren T.K. Kaptan A.Y. Bircan R. Tosun M.F. Kanatlı U. Lesion prevalence and patient outcome comparison between primary and recurrent anterior shoulder instability J Shoulder Elbow Surg 32 2023 1812 1818 10.1016/j.jse.2023.05.029 37419438
26 Godin J. Sekiya J.K. Systematic review of rehabilitation versus operative stabilization for the treatment of first-time anterior shoulder dislocations Sports Health 2 2010 156 165 10.1177/1941738109359507 23015933
27 Grumet R.C. Bach B.R. Provencher M.T. Arthroscopic stabilization for first-time versus recurrent shoulder instability Arthrosc J Arthrosc Relat Surg 26 2010 239 248 10.1016/j.arthro.2009.06.006
28 Gutierrez V. Monckeberg J.E. Pinedo M. Radice F. Arthroscopically determined degree of injury after shoulder dislocation relates to recurrence rate Clin Orthop Relat Res 470 2012 961 964 10.1007/s11999-011-2229-8 22258562
29 Habermeyer P. Gleyze P. Rickert M. Evolution of lesions of the labrum-ligament complex in posttraumatic anterior shoulder instability: a prospective study J Shoulder Elbow Surg 8 1999 66 74 10077800
30 Hattrup S.J. Cofield R.H. Weaver A.L. Anterior shoulder reconstruction: prognostic variables J Shoulder Elbow Surg 10 2001 508 513 11743527
31 Hong J. Huang Y. Ma C. Qu G. Meng J. Wu H. Risk factors for anterior shoulder instability: a matched case-control study J Shoulder Elbow Surg 28 2019 869 874 10.1016/j.jse.2018.09.014 30509611
32 Hovelius L. Augustini B.G. Fredin H. Johansson O. Norlin R. Thorling J. Primary anterior dislocation of the shoulder in young patients. A ten-year prospective study J Bone Joint Surg Am 78 1996 1677 1684 8934481
33 Hovelius L. Olofsson A. Sandström B. Augustini B.-G. Krantz L. Fredin H. Nonoperative treatment of primary anterior shoulder dislocation in patients forty years of age and younger: a prospective twenty-five-year follow-up J Bone Joint Surg Am 90 2008 945 952 10.2106/JBJS.G.00070 18451384
34 Hovelius L. Saeboe M. Neer Award 2008: arthropathy after primary anterior shoulder dislocation–223 shoulders prospectively followed up for twenty-five years J Shoulder Elbow Surg 18 2009 339 347 10.1016/j.jse.2008.11.004 19254851
35 Hurley E.T. Manjunath A.K. Bloom D.A. Pauzenberger L. Mullett H. Alaia M.J. Arthroscopic Bankart repair versus conservative management for first-time traumatic anterior shoulder instability: a systematic review and meta-analysis Arthrosc J Arthrosc Relat Surg 36 2020 2526 2532 10.1016/j.arthro.2020.04.046
36 Hutyra C.A. Streufert B. Politzer C.S. Agaba P. Rubin E. Orlando L.A. Assessing the effectiveness of evidence-based medicine in practice: a case study of first-time anterior shoulder dislocations J Bone Joint Surg Am 101 2019 e6 10.2106/JBJS.17.01588
37 Itoi E. Hatakeyama Y. Sato T. Kido T. Minagawa H. Yamamoto N. Immobilization in external rotation after shoulder dislocation reduces the risk of recurrence: a randomized controlled trial J Bone Joint Surg Am 89 2007 2124 2131 10.2106/JBJS.F.00654 17908886
38 Kim D.-S. Yi C.-H. Yoon Y.-S. Arthroscopic repair for combined Bankart and superior labral anterior posterior lesions: a comparative study between primary and recurrent anterior dislocation in the shoulder Int Orthop 35 2011 1187 1195 10.1007/s00264-011-1229-3 21369793
39 Kim D.-S. Yoon Y.-S. Yi C.H. Prevalence comparison of accompanying lesions between primary and recurrent anterior dislocation in the shoulder Am J Sports Med 38 2010 2071 2076 10.1177/0363546510371607 20709942
40 Kirkley A. Griffin S. Richards C. Miniaci A. Mohtadi N. Prospective randomized clinical trial comparing the effectiveness of immediate arthroscopic stabilization versus immobilization and rehabilitation in first traumatic anterior dislocations of the shoulder Arthrosc J Arthrosc Relat Surg 15 1999 507 514
41 Kirkley A. Werstine R. Ratjek A. Griffin S. Prospective randomized clinical trial comparing the effectiveness of immediate arthroscopic stabilization versus immobilization and rehabilitation in first traumatic anterior dislocations of the shoulder: long-term evaluation Arthrosc J Arthrosc Relat Surg 21 2005 55 63 10.1016/j.arthro.2004.09.018
42 Kordasiewicz B. Małachowski K. Kicinski M. Chaberek S. Pomianowski S. Comparative study of open and arthroscopic coracoid transfer for shoulder anterior instability (Latarjet)—clinical results at short term follow-up Int Orthop 41 2017 1023 1033 10.1007/s00264-016-3372-3 28039495
43 Kraeutler M.J. McCarty E.C. Belk J.W. Wolf B.R. Hettrich C.M. Ortiz S.F. Descriptive epidemiology of the MOON shoulder instability cohort Am J Sports Med 46 2018 1064 1069 10.1177/0363546518755752 29505730
44 Leroux T. Wasserstein D. Veillette C. Khoshbin A. Henry P. Chahal J. Epidemiology of primary anterior shoulder dislocation requiring closed reduction in ontario, Canada Am J Sports Med 42 2014 442 450 10.1177/0363546513510391 24275862
45 Longo U.G. Van Der Linde J.A. Loppini M. Coco V. Poolman R.W. Denaro V. Surgical versus nonoperative treatment in patients up to 18 Years old with traumatic shoulder instability: a systematic review and quantitative synthesis of the literature Arthrosc J Arthrosc Relat Surg 32 2016 944 952 10.1016/j.arthro.2015.10.020
46 MacDonald P. McRae S. Old J. Marsh J. Dubberley J. Stranges G. Arthroscopic Bankart repair with and without arthroscopic infraspinatus remplissage in anterior shoulder instability with a Hill-Sachs defect: a randomized controlled trial J Shoulder Elbow Surg 30 2021 1288 1298 10.1016/j.jse.2020.11.013 33373683
47 Marquardt B. Garmann S. Schulte T. Witt K.-A. Steinbeck J. Pötzl W. Outcome after failed traumatic anterior shoulder instability repair with and without surgical revision J Shoulder Elbow Surg 16 2007 742 747 10.1016/j.jse.2007.02.132 17967548
48 Marshall T. Vega J. Siqueira M. Cagle R. Gelber J.D. Saluan P. Outcomes after arthroscopic Bankart repair: patients with first-time versus recurrent dislocations Am J Sports Med 45 2017 1776 1782 10.1177/0363546517698692 28384005
49 Murphy A.I. Hurley E.T. Hurley D.J. Pauzenberger L. Mullett H. Long-term outcomes of the arthroscopic Bankart repair: a systematic review of studies at 10-year follow-up J Shoulder Elbow Surg 28 2019 2084 2089 10.1016/j.jse.2019.04.057 31311748
50 Owens B.D. Duffey M.L. Nelson B.J. DeBerardino T.M. Taylor D.C. Mountcastle S.B. The incidence and characteristics of shoulder instability at the United States military academy Am J Sports Med 35 2007 1168 1173 10.1177/0363546506295179 17581976
51 Porcellini G. Campi F. Pegreffi F. Castagna A. Paladini P. Predisposing factors for recurrent shoulder dislocation after arthroscopic treatment J Bone Joint Surg Am 91 2009 2537 2542 10.2106/JBJS.H.01126 19884424
52 Provencher M.T. Midtgaard K.S. Owens B.D. Tokish J.M. Diagnosis and management of traumatic anterior shoulder instability J Am Acad Orthop Surg 29 2021 e51 e61 10.5435/JAAOS-D-20-00202 33275397
53 Robinson C.M. Dobson R.J. Anterior instability of the shoulder after trauma J Bone Joint Surg Br 86-B 2004 469 479 10.1302/0301-620X.86B4.15014
54 Robinson C.M. Howes J. Murdoch H. Will E. Graham C. Functional outcome and risk of recurrent instability after primary traumatic anterior shoulder dislocation in young patients J Bone Joint Surg Am 88 2006 2326 2336 10.2106/JBJS.E.01327 17079387
55 Rowe C.R. Prognosis in dislocations of the shoulder J Bone Joint Surg Am 38-A 1956 957 977 13367074
56 Rutgers C. Verweij L.P.E. Priester-Vink S. Van Deurzen D.F.P. Maas M. Van Den Bekerom M.P.J. Recurrence in traumatic anterior shoulder dislocations increases the prevalence of Hill–Sachs and Bankart lesions: a systematic review and meta-analysis Knee Surg Sports Traumatol Arthrosc 30 2022 2130 2140 10.1007/s00167-021-06847-7 34988633
57 Shah A. Judge A. Delmestri A. Edwards K. Arden N.K. Prieto-Alhambra D. Incidence of shoulder dislocations in the UK, 1995–2015: a population-based cohort study BMJ Open 7 2017 e016112 10.1136/bmjopen-2017-016112
58 Speer K.P. Warren R.F. Pagnani M. Warner J.J.P. An arthroscopic technique for anterior stabilization of the shoulder with a bioabsorbable tack J Bone Joint Surg Am 78 1996 1801 1807 8986656
59 Streufert B. Reed S.D. Orlando L.A. Taylor D.C. Huber J.C. Mather R.C. Understanding preferences for treatment after hypothetical first-time anterior shoulder dislocation: surveying an online panel utilizing a novel shared decision-making tool Orthop J Sports Med 5 2017 232596711769578 10.1177/2325967117695788
60 Van Der Linde J.A. Bosmans J.E. Ter M.D.P. Van Kampen D.A. Van Deurzen D.F. Haverlag R. Direct and indirect costs associated with nonoperative treatment for shoulder instability: an observational study in 132 patients Shoulder Elbow 11 2019 265 274 10.1177/1758573218773543 31316587
61 Wasserstein D.N. Sheth U. Colbenson K. Henry P.D.G. Chahal J. Dwyer T. The true recurrence rate and factors predicting recurrent instability after nonsurgical management of traumatic primary anterior shoulder dislocation: a systematic review Arthrosc J Arthrosc Relat Surg 32 2016 2616 2625 10.1016/j.arthro.2016.05.039
62 Waterman B. Owens B.D. Tokish J.M. Anterior shoulder instability in the military athlete Sports Health 8 2016 514 519 10.1177/1941738116672161 27694151
63 Wheeler J.H. Ryan J.B. Arciero R.A. Molinari R.N. Arthroscopic versus nonoperative treatment of acute shoulder dislocations in young athletes Arthrosc J Arthrosc Relat Surg 5 1989 213 217
64 Zacchilli M.A. Owens B.D. Epidemiology of shoulder dislocations presenting to emergency departments in the United States J Bone Joint Surg Am 92 2010 542 549 10.2106/JBJS.I.00450 20194311
