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Shoulder Clicking, Popping and Instability

Why a shoulder clicks, pops or feels like it slips — from harmless noises to labral tears and instability — what it means, and when it needs attention.

Overview

Shoulder instability management requires precise patient selection and modality choice based on lesion morphology and patient factors. Indications for surgical intervention are primarily determined by a thorough clinical exam, which supersedes radiologic findings; outcomes for posterior shoulder instability surgery do not differ between patients with normal versus pathological magnetic resonance arthrogram studies [3]. For anterior instability, age, labral lesion type, and lesion location are key risk factors for recurrence following arthroscopic labrum repair at minimum 10-year follow-up [13]. Isolated arthroscopic Bankart repair (ABR) for on-track Hill-Sachs lesions with <20% glenoid bone loss is associated with high rates of recurrent instability and inferior patient-reported outcomes at mean 10-year follow-up [4].

Contemporary evidence supports comparable instability and functional outcomes between arthroscopic and open Bankart repair approaches, with historical differences driven by earlier studies [7]. For multidirectional shoulder instability and Ehlers-Danlos syndrome, open capsular shift with Achilles allograft augmentation demonstrates low rates of recurrent instability and improved clinical outcomes [1]. Recurrent anterior shoulder dislocation can be accompanied by a posterior humeral avulsion of the glenohumeral ligament (PHAGL) lesion, with a prevalence rate of approximately 6.2% [12]. Coracoid morphology differs significantly in patients undergoing posterior shoulder stabilization compared to patients undergoing surgery for anterior instability or a comparison cohort [5].

Posterior instability presents unique diagnostic and management challenges. NHL team physicians strongly favor nonoperative management in-season for initial posterior instability events of the shoulder [2]. Traumatic posterior shoulder dislocation can occur in association with a posterior acromion fracture [8]. Bilateral posterior shoulder dislocations with reverse Hill-Sachs lesions are uncommon, prone to misdiagnosis, and require early recognition and tailored treatment strategies for satisfactory functional outcomes [10]. Clinicians should be aware that spin is highly prevalent in abstracts of systematic reviews and meta-analyses investigating free bone block procedures for glenohumeral instability [6].

Background & Causes

Surgical Indications and Preoperative Assessment A thorough clinical exam is the most important factor when determining indication for shoulder instability surgery, with no difference in outcomes for posterior shoulder instability surgery based on normal vs. pathological radiologist-reported magnetic resonance arthrogram findings [3]. Bony lesions, including glenoid bone loss and Hill-Sachs lesions, play a significant role in shaping surgical treatment decisions for first-time anterior shoulder dislocation [15]. The Instability Severity Index Score and the Hill-Sachs interval-to-glenoid track ratio composite score show good predictive performance for recurrence after arthroscopic Bankart repair [11].

Risk Factors for Recurrence Age, labral lesion type, and lesion location are key risk factors for recurrence following arthroscopic labrum repair in patients with anterior shoulder instability at a minimum 10-year follow-up [13]. Rates of recurrent anterior shoulder instability were high following isolated arthroscopic Bankart repair (ABR) for on-track Hill-Sachs lesions with <20% glenoid bone loss, associated with inferior patient-reported outcomes at mean 10-year follow-up [4]. A risk prediction model has been developed and validated to identify patients at high risk for rotator cuff tears following acute anterior shoulder dislocation [21].

Anatomical and Morphological Considerations Coracoid morphology differs significantly in patients undergoing posterior shoulder stabilization compared to patients undergoing surgery for anterior instability or a comparison cohort [5]. Labral morphology does not compensate for reduced bony glenoid concavity in clinically stable shoulders [18]. Bilateral posterior shoulder dislocations with reverse Hill-Sachs lesions are uncommon and prone to misdiagnosis [10].

Operative Techniques and Management Strategies Nonoperative Management: NHL team physicians strongly favor nonoperative management in-season for initial posterior instability events of the shoulder [2]. Arthroscopic vs. Open Repair: Contemporary studies show comparable instability and functional outcomes between arthroscopic and open Bankart repair approaches, whereas historical differences were driven primarily by earlier studies [7]. Posterior Stabilization: The modified Kouvalchouk procedure is used for stabilization of recurrent posterior unstable shoulders in traumatic cases and patients without previous surgery [9]. Open capsular shift with Achilles allograft augmentation is used for multidirectional shoulder instability in patients with Ehlers-Danlos syndrome [1]. End-Stage Instability: Reverse shoulder arthroplasty and glenohumeral arthrodesis are viable options for treating end-stage recurrent shoulder instability [14].

Associated Injuries and Reporting Bias Traumatic posterior shoulder dislocation can occur in association with a posterior acromion fracture [8]. Spin is highly prevalent in abstracts of systematic reviews and meta-analyses investigating free bone block procedures for glenohumeral instability [6].

Symptoms & Presentation

Lesion Associations: Recurrent anterior shoulder dislocation can be accompanied by a posterior humeral avulsion of the glenohumeral ligament (PHAGL) lesion, with a prevalence rate of approximately 6.2% [12]. Traumatic posterior shoulder dislocation can occur in association with a posterior acromion fracture [8].

Diagnostic Challenges: Bilateral posterior shoulder dislocations with reverse Hill-Sachs lesions are uncommon and prone to misdiagnosis [10].

Management

Non-Operative Management

In-season management: NHL team physicians strongly favor nonoperative management for initial posterior instability events of the shoulder [2]. Postoperative adjuncts: Kinesio taping has a clear augmentative effect as an adjunctive measure for postoperative rehabilitation in military personnel with recurrent shoulder dislocation [17].

Surgical Decision-Making and Predictors

Clinical assessment: A thorough clinical exam is the most important factor when determining indication for shoulder instability surgery [3]. Bony pathology: Bony lesions, including glenoid bone loss and Hill-Sachs lesions, play a significant role in shaping surgical treatment decisions for first-time anterior shoulder dislocation [15]. Risk stratification: The Instability Severity Index Score and the Hill-Sachs interval-to-glenoid track ratio composite score showed good predictive performance for recurrence after arthroscopic Bankart repair (ABR) [11].

Anterior Instability Surgery

Isolated ABR limitations: Isolated arthroscopic Bankart repair (ABR) for on-track Hill-Sachs lesions with <20% glenoid bone loss is associated with high rates of recurrent anterior shoulder instability and inferior patient-reported outcomes at mean 10-year follow-up [4]. Multidirectional instability: Open capsular shift with Achilles allograft augmentation demonstrates low rates of recurrent instability and improved clinical outcomes in patients with multidirectional shoulder instability, including those with Ehlers-Danlos Syndrome [1]. Significant bone loss: Arthroscopic distal tibial allograft (DTA) bone block glenoid reconstruction using 2 pairs of suture buttons for recurrent traumatic anterior instability with significant bone loss yields high rates of graft union and improves clinical outcomes at 2 years [20]. Bipolar bone loss: Arthroscopic Bankart repair with arthroscopic bone augmentation of the anterior glenoid wall and concomitant remplissage results in favorable outcomes for young patients with severe bipolar bone loss [19]. Return-to-play: Return-to-play rates are similar between open and arthroscopic anterior shoulder stabilization approaches in contact and collision athletes [16].

Posterior Instability Surgery

Anatomic considerations: Coracoid morphology differs significantly in patients undergoing posterior shoulder stabilization compared to patients undergoing surgery for anterior instability or a comparison cohort [5]. Traumatic recurrent cases: The modified Kouvalchouk procedure provides good results for stabilizing recurrent posterior unstable shoulders in traumatic cases and patients without previous surgery, utilizing local harvesting of a bone block and a potential sling effect [9]. Bilateral dislocations: Bilateral posterior shoulder dislocations with reverse Hill-Sachs lesions are uncommon, prone to misdiagnosis, and require early recognition and tailored treatment strategies for satisfactory functional outcomes [10].

Associated Lesions

PHAGL prevalence: Recurrent anterior shoulder dislocation can be accompanied by a posterior humeral avulsion of the glenohumeral ligament (PHAGL) lesion, with a prevalence rate of approximately 6.2% [12].

End-Stage Instability

Salvage options: Total shoulder arthroplasty (TSA) and glenohumeral arthrodesis (GHA) are viable options for treating end-stage recurrent shoulder instability [14].

Key Considerations

Diagnostic Evaluation: A thorough clinical exam is the most important factor when determining indication for shoulder instability surgery, with no difference in outcomes for posterior shoulder instability surgery between patients with normal vs. pathological radiologist-reported magnetic resonance arthrogram studies [3]. Coracoid morphology differs significantly in patients undergoing posterior shoulder stabilization compared to patients undergoing surgery for anterior instability or a comparison cohort [5]. Recurrent anterior shoulder dislocation can be accompanied by a posterior humeral avulsion of the glenohumeral ligament (PHAGL) lesion, with a prevalence rate of approximately 6.2% [12].

Surgical Indications and Risk Stratification: Age, labral lesion type, and lesion location are key risk factors for recurrence following arthroscopic labrum repair in patients with anterior shoulder instability at a minimum 10-year follow-up [13]. The Instability Severity Index Score and the Hill-Sachs interval-to-glenoid track ratio composite score show good predictive performance for recurrence after arthroscopic Bankart repair in patients with <20% glenoid bone loss [11]. Rates of recurrent anterior shoulder instability were high following isolated arthroscopic Bankart repair (ABR) for on-track Hill-Sachs lesions with <20% glenoid bone loss, associated with inferior patient-reported outcomes at mean 10-year follow-up [4].

Anterior Stabilization Techniques: Contemporary studies show comparable instability and functional outcomes between arthroscopic and open Bankart repair approaches, whereas historical differences were driven primarily by earlier studies [7]. Open fresh and arthroscopic frozen distal tibial allograft (DTA) for anatomic glenoid reconstruction in patients with recurrent anterior shoulder instability result in a clinically stable joint with comparable outcomes and excellent healing rates [22].

Posterior Stabilization Techniques: NHL team physicians strongly favor nonoperative management in-season for initial posterior instability events of the shoulder [2] . Traumatic posterior shoulder dislocation can occur in association with a posterior acromion fracture [8]. The modified Kouvalchouk procedure provides good results in stabilizing recurrent posterior unstable shoulders in traumatic cases and patients without previous surgery, offering the advantages of local harvesting of a bone block and a potential sling effect [9].

Complex and Revision Instability: Open capsular shift with Achilles allograft augmentation demonstrates low rates of recurrent instability and improved clinical outcomes in patients with multidirectional shoulder instability and Ehlers-Danlos syndrome [1]. Total shoulder arthroplasty (TSA) and glenohumeral arthrodesis (GHA) are viable options for treating end-stage recurrent shoulder instability [14].

Rehabilitation and Research Integrity: Kinesio taping has a clear augmentative effect as an adjunctive measure for postoperative rehabilitation in military personnel with recurrent shoulder dislocation caused by training injury [17]. Spin is highly prevalent in abstracts of systematic reviews and meta-analyses investigating free bone block procedures for glenohumeral instability [6].

Key Evidence

  • [L4] The study demonstrated low rates of recurrent instability and improved clinical outcomes in this high-risk population. (10.1016/j.jse.2026.05.024)
  • [L4] NHL team physicians strongly favor nonoperative management in-season for initial posterior instability events of the shoulder. (10.1177/23259671261440208)
  • [L3] A thorough clinical exam is the most important factor when determining indication for shoulder instability surgery. (10.1016/j.xrrt.2026.100675)
  • [L3] Rates of recurrent anterior shoulder instability were high following isolated ABR for on-track HSLs with <20% glenoid bone loss and were associated with inferior PROs at mean 10-year follow-up. (10.1177/23259671261430742)
  • [L3] Coracoid morphology differs significantly in patients undergoing posterior shoulder stabilization when compared to patients undergoing surgery for anterior instability or a comparison cohort. (10.1177/03635465261421534)
  • [L4] Spin is highly prevalent in abstracts of systematic reviews and meta-analyses investigating FBB for glenohumeral instability. (10.1177/03635465251338079)
  • [L4] Publication period subgroup analysis suggests that historical instability differences were driven primarily by earlier studies, whereas contemporary studies show comparable instability and functional outcomes between approaches. (10.1177/03635465261443999)
  • [L4] Two cases document an unusual injury pattern in which a posterior glenohumeral dislocation occurred in association with a (posterior) acromion fracture. (10.1016/j.xrrt.2025.09.006)
  • [L4] The modified Kouvalchouk procedure provides good results in the stabilization of recurrent posterior unstable shoulders in traumatic cases and patients without previous surgery, with the advantage of local harvesting of a bone block and a potential sling effect. (10.1016/j.jseint.2026.101681)
  • [L4] Bilateral posterior shoulder dislocations with reverse Hill-Sachs lesions are uncommon and prone to misdiagnosis; early recognition and tailored treatment strategies are essential for satisfactory functional outcomes. (10.1186/s12891-026-09537-y)
  • [L3] The Instability Severity Index Score and the Hill-Sachs interval-to-glenoid track ratio composite score showed good predictive performance for recurrence after ABR. (10.1002/arj.70009)
  • [L4] Recurrent anterior shoulder dislocation can be accompanied by a PHAGL lesion, with a prevalence rate of approximately 6.2%. (10.1016/j.jse.2025.04.020)
  • [L4] Age, labral lesion type, and lesion location are key risk factors for recurrence following arthroscopic labrum repair in patients with anterior shoulder instability at a minimum 10-year follow-up. (10.1016/j.jse.2025.03.034)
  • [L2] TSA and GHA are viable options in treating end-stage recurrent shoulder instability. (10.1016/j.jseint.2025.101429)
  • [L5] Our findings highlight the significant role of bony lesions, including glenoid bone loss and Hill-Sachs lesions, in shaping surgical treatment decisions. (10.1016/j.jse.2025.07.018)
  • [L2] However, similar return‐to‐play rates are seen with either approach. (10.1002/ksa.70263)
  • [L4] This suggests kinesio taping has a clear augmentative effect as an adjunctive measure for postoperative rehabilitation in military personnel with recurrent shoulder dislocation. (10.1186/s12891-026-09753-6)
  • [L4] This study demonstrates that labral morphology does not compensate for reduced bony glenoid concavity in clinically stable shoulders. (10.1016/j.jseint.2025.101422)
  • [Case_report] This case report demonstrates the efficacy of an arthroscopic Bankart with an arthroscopic bone augmentation of the anterior glenoid wall, in conjunction with an additional remplissage procedure, resulting in a favorable outcome for a young patient with extensive sporting activity. (10.1016/j.xrrt.2025.100606)
  • [L4] Arthroscopic DTA bone block glenoid reconstruction using 2 pairs of suture buttons to treat recurrent traumatic anterior instability with significant bone loss yields improved clinical and acceptable radiological outcomes. (10.1002/arj.70008)
  • [L3] The findings may assist orthopedic surgeons in identifying patients at high risk for RCT after shoulder dislocation. (10.1186/s12891-026-09550-1)
  • [L4] Open fresh and arthroscopic frozen DTA for anatomic glenoid reconstruction in patients with recurrent anterior shoulder instability resulted in a clinically stable joint with comparable outcomes and excellent healing rates. (10.1177/03635465251399165)

References

[1] Open Capsular Shift with Achilles Allograft Augmentation for Multidirectional Shoulder Instability: Long-Term Outcomes and Implications for Patients with Ehlers-Danlos Syndrome. Journal of Shoulder and Elbow Surgery. 2026. DOI: 10.1016/j.jse.2026.05.024

[2] Treatment of Posterior Shoulder Instability in National Hockey League Players: A Survey of NHL Team Physicians. Orthopaedic Journal of Sports Medicine. 2026. DOI: 10.1177/23259671261440208

[3] No difference in outcomes for posterior shoulder instability surgery in patients with a normal vs. pathological radiologist reported magnetic resonance arthrogram study. JSES Reviews, Reports, and Techniques. 2026. DOI: 10.1016/j.xrrt.2026.100675

[4] Long-Term Outcomes following Instability After Isolated Arthroscopic Bankart Repair for On-Track Hill-Sachs Lesions With <20% Glenoid Bone Loss. Orthopaedic Journal of Sports Medicine. 2026. DOI: 10.1177/23259671261430742

[5] Coracoid Morphology and the Risk of Posterior Shoulder Instability: A Magnetic Resonance Imaging Study. The American Journal of Sports Medicine. 2026. DOI: 10.1177/03635465261421534

[6] Appraisal of the Presence of Spin in Abstracts of Systematic Reviews and Meta-analyses Regarding Free Bone Block Procedures for Glenohumeral Instability. The American Journal of Sports Medicine. 2026. DOI: 10.1177/03635465251338079

[7] Arthroscopic vs Open Bankart Repair for Anterior Shoulder Instability: A Systematic Review and Meta-analysis. The American Journal of Sports Medicine. 2026. DOI: 10.1177/03635465261443999

[8] Traumatic posterior shoulder dislocation with associated acromion fracture: a report of 2 cases. JSES Reviews, Reports, and Techniques. 2026. DOI: 10.1016/j.xrrt.2025.09.006

[9] Modified Kouvalchouk technique for recurrent posterior instability of the shoulder. JSES International. 2026. DOI: 10.1016/j.jseint.2026.101681

[10] Bilateral posterior shoulder dislocations with reverse Hill-Sachs lesions: a report of two cases and a literature review. BMC Musculoskeletal Disorders. 2026. DOI: 10.1186/s12891-026-09537-y

[11] Combining Instability Severity Index Score and Hill‐Sachs Interval‐to‐Glenoid Track Ratio Predicts Recurrent Instability After Arthroscopic Bankart Repair in Patients With <20% Glenoid Bone Loss. Arthroscopy. 2026. DOI: 10.1002/arj.70009

[12] Clinical outcomes following arthroscopic repair of posterior humeral avulsion of glenohumeral ligament in recurrent anterior shoulder dislocations. Journal of Shoulder and Elbow Surgery. 2026. DOI: 10.1016/j.jse.2025.04.020

[13] Age, labral lesion type, and lesion location are key risk factors for recurrence following arthroscopic labrum repair in patients with anterior shoulder instability: a minimum 10-year follow-up study. Journal of Shoulder and Elbow Surgery. 2026. DOI: 10.1016/j.jse.2025.03.034

[14] A comparison of reverse shoulder arthroplasty and glenohumeral arthrodesis for end-stage shoulder instability. JSES International. 2026. DOI: 10.1016/j.jseint.2025.101429

[15] Management of a first time anterior shoulder dislocation: the decision-making process of a surgeon. Journal of Shoulder and Elbow Surgery. 2026. DOI: 10.1016/j.jse.2025.07.018

[16] Return to play and recurrent instability rates in open versus arthroscopic anterior shoulder stabilisation in the contact and collision athlete: A systematic review. Knee Surgery, Sports Traumatology, Arthroscopy. 2026. DOI: 10.1002/ksa.70263

[17] A retrospective analysis of the promoting effect of kinesio taping on the rehabilitation of military personnel with recurrent shoulder dislocation caused by training injury. BMC Musculoskeletal Disorders. 2026. DOI: 10.1186/s12891-026-09753-6

[18] Labral morphology does not compensate for reduced bony glenoid concavity in stable shoulders. JSES International. 2026. DOI: 10.1016/j.jseint.2025.101422

[19] Arthroscopic bone block using an autologous iliac crest graft and concomitant remplissage for severe bipolar bone loss in a young patient with anterior shoulder instability: a case report. JSES Reviews, Reports, and Techniques. 2026. DOI: 10.1016/j.xrrt.2025.100606

[20] Arthroscopic Distal Tibial Allograft Reconstruction With Suture Button Fixation and Capsulolabral Repair for Traumatic Anterior Shoulder Instability Yields High Rates of Graft Union and Improves Clinical Outcomes at 2 Years. Arthroscopy. 2026. DOI: 10.1002/arj.70008

[21] Development and validation of a risk prediction model for rotator cuff tears following acute anterior shoulder dislocation. BMC Musculoskeletal Disorders. 2026. DOI: 10.1186/s12891-026-09550-1

[22] Surgical Stabilization for Recurrent Shoulder Instability Using Distal Tibial Allograft: Open Technique With Fresh Allograft Versus Arthroscopic Technique With Frozen Allograft, a Cohort Study. The American Journal of Sports Medicine. 2026. DOI: 10.1177/03635465251399165

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a. For the avoidance of doubt, this Public License does not, and shall not be interpreted to, reduce, limit, restrict, or impose conditions on any use of the Licensed Material that could lawfully be made without permission under this Public License.

b. To the extent possible, if any provision of this Public License is deemed unenforceable, it shall be automatically reformed to the minimum extent necessary to make it enforceable. If the provision cannot be reformed, it shall be severed from this Public License without affecting the enforceability of the remaining terms and conditions.

c. No term or condition of this Public License will be waived and no failure to comply consented to unless expressly agreed to by the Licensor.

d. Nothing in this Public License constitutes or may be interpreted as a limitation upon, or waiver of, any privileges and immunities that apply to the Licensor or You, including from the legal processes of any jurisdiction or authority.

Creative Commons is not a party to its public licenses. Notwithstanding, Creative Commons may elect to apply one of its public licenses to material it publishes and in those instances will be considered the “Licensor.” The text of the Creative Commons public licenses is dedicated to the public domain under the CC0 Public Domain Dedication. Except for the limited purpose of indicating that material is shared under a Creative Commons public license or as otherwise permitted by the Creative Commons policies published at creativecommons.org/policies, Creative Commons does not authorize the use of the trademark "Creative Commons" or any other trademark or logo of Creative Commons without its prior written consent including, without limitation, in connection with any unauthorized modifications to any of its public licenses or any other arrangements, understandings, or agreements concerning use of licensed material. For the avoidance of doubt, this paragraph does not form part of the public licenses.

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