Skip to content

Distal Clavicle Osteolysis

Overview

Distal clavicle resection is a necessary intervention to relieve symptoms in appropriately selected patients with persistent pain or posttraumatic arthritis [4]. While routine excision is not absolutely necessary for all cases of symptomatic acromioclavicular joint osteoarthritis [20], the procedure reliably produces significant improvement in chronic conditions. For old dislocations, excision of the outer end of the clavicle is preferred over open reduction and internal fixation, which are associated with complications and poor functional results [13]. In cases of chronic symptomatic injuries, partial claviculectomy is considered the optimal procedure due to negligible morbidity and rapid return to function [14].

Outcomes vary by pathology and technique. Arthroscopic distal clavicle excision via a direct approach facilitates a faster return to activities compared with open procedures while achieving similar long-term outcomes [2]. Although arthroscopic resection has yielded more 'good or excellent' results than open surgery, this finding relies on low-level evidence [8]. Both approaches provide significant pain reduction at one year with no significant difference in most outcome measures, except for VAS pain score improvement [17]. A well-performed excision likely outperforms a poorly performed one regardless of the approach chosen [9]. Total claviculectomy remains a viable option for chronic clavicular dislocation with excellent outcomes [22], though it yields unsatisfying results for chronic posttraumatic pain despite full range of motion [27]. In specific infectious cases, such as Propionibacterium acnes–mediated osteolysis, resection combined with antibiotics can halt disease progression [1].

Anatomy & Pathophysiology

Kinematics and Biomechanics

A precise, low-cost, non-invasive method to draw and analyze shoulder complex kinematics has not yet been developed [29], though normative kinematic values for scapulothoracic movements in the shoulder girdle have been provided [30]. In AC separation models, scapular and clavicular kinematics are affected, and these changes represent a potential source of pain and dysfunction [33, 34]. No reconstruction strategy completely restores the shoulder girdle to its preinjured state, although each technique restores different elements of joint kinematics [31]. Preliminary findings revealed no detectable differences between surgically reconstructed and uninjured sides regarding ACJ biomechanics, range of motion, and isometric strength [41], whereas nonoperatively treated shoulders demonstrated increased internal rotation, upward rotation, and posterior tilting [41].

Ligamentous and Osseous Mechanics

The trapezoid and conoid ligaments possess unique functions in normal shoulder kinematics due to their specific anatomic attachments [32]. Biomechanically, the pectoralis minor tendon is as strong as the coracoacromial ligament and provides sufficient tissue length, excursion, and width [37]. At 150 to 200 N of loading, coracoacromial ligament excision and acromioplasty increase the rotator cuff force required to maintain normal glenohumeral biomechanics by 25% to 30% [44]. Regarding coracoclavicular stabilization, no significant biomechanical differences in displacement or stiffness were observed between the anatomical landmark technique and the coracoid-based landmarks technique [38].

Clinical Implications and Assessment

Type I and II acromioclavicular joint disruptions impair long-term shoulder function in approximately half of patients 10 years after injury [43]. Centre of pressure measurements have detected sensorimotor functional deficits following surgical treatment in patients with confirmed successful clinical and functional outcomes [45]. The inconsistency of AC joint testing parameters and the lack of thorough translation studies indicate a necessity for increased attention to the overall assessment of shoulder stability to close the gap in foundational biomechanical research [36]. A comprehensive clinical approach emphasizing the evaluation of the extent of anatomic injury and understanding its mechanical consequences regarding shoulder and arm function is key to developing operative or non-operative treatment protocols and establishing outcomes [35]. New surgical techniques continue to evolve as more biomechanical data emerge and kinematic understanding improves [39], with emerging concepts regarding horizontal and rotational instability and scapular biomechanics aiming to lay the foundation for future studies aimed at improving treatment outcomes and patient management [40].

Classification

Modified Rockwood: The ISAKOS Upper Extremity Committee proposes adding grade IIIA and grade IIIB to the Rockwood classification to distinguish stable type III injuries from unstable grade III injuries characterized by therapy-resistant scapular dysfunction and an overriding clavicle [50].

Other Considerations: Horizontal instability of the clavicle is evident with distal clavicle resection exceeding 10 mm [11]. Patients with displacement greater than 100% of the thickness of the distal clavicle demonstrated poorer postoperative clinical outcomes [6]. Incomplete excision and regrowth of the distal clavicle remain the most common causes of revision [10]. Propionibacterium acnes–mediated distal clavicular osteolysis represents a distinct etiology treatable with distal clavicle resection and antibiotics [1]. Gorham-Stout disease is a differential diagnosis to consider in patients presenting with massive osteolysis following shoulder surgery [3]. Methods to diagnose both superior and posterior translation of the clavicle require further debate [15].

Clinical Presentation

The clinical picture of distal clavicle osteolysis is heterogeneous, ranging from infectious etiologies to iatrogenic complications. Etiology: The condition can be mediated by Propionibacterium acnes [1] or arise as a complication following shoulder surgery, such as posterior shoulder capsulorrhaphy [3]. Iatrogenic Risk: Aggressive burring during shoulder arthroscopy, often due to misidentification of the AC joint, presents a risk for distal clavicle fracture [26].

Physical examination must account for specific radiological and mechanical findings. Instability Patterns: Horizontal instability of the clavicle is evident with distal clavicle resection of greater than 10 mm [11]. While methods to diagnose both superior and posterior translation of the clavicle need further debate [15], radiological assessment has shown a statistically significant immediate superior clavicular displacement after hardware removal following acromioclavicular joint stabilization using a suspensory fixation system [18]. Structural Complications: Segmental fractures of the clavicle are easily missed and may present with acromioclavicular joint disruption [21]. Late loss of reduction is common following acromioclavicular joint dislocation [5].

Postoperative and long-term sequelae significantly influence outcomes and require vigilant monitoring. Outcomes: Patients with displacement greater than 100% of the thickness of the distal clavicle have poorer postoperative clinical outcomes [6]. Hardware-Related Changes: Subacromial osteolysis has a relatively high and variable incidence following hook plate fixation for acromioclavicular dislocation [12]. Furthermore, clavicular tunnel widening was observed in 70% of patients at final follow-up after coracoclavicular stabilization surgery [16].

Investigations

Plain radiography: Weighted stress views significantly increase measured clavicular elevation and coracoclavicular distance compared to non-weighted views in acute acromioclavicular joint dislocations [47]. Radiological assessment reveals a statistically significant immediate superior clavicular displacement after hardware removal following stabilization with a suspensory fixation system, with incidence increasing in the first year post-stabilization [18]. Massive osteolysis following shoulder surgery warrants consideration of Gorham-Stout disease [3]. Segmental fractures of the clavicle are easily missed on standard imaging [21].

MRI: A high index of suspicion is required to diagnose bone osteolysis following acromioclavicular joint reconstruction using synthetic ligaments early, prior to the occurrence of irretrievable bone loss [54].

CT: Horizontal instability of the clavicle becomes evident with distal clavicle resection exceeding 10 mm [11]. Patients with displacement greater than 100% of the distal clavicle thickness demonstrate poorer postoperative clinical outcomes after acromioclavicular joint dislocation treated with an endobutton device [6].

Bone scan: Subacromial osteolysis following hook plate fixation for acromioclavicular dislocation occurs with a relatively high and variable incidence, primarily influenced by the radiological assessment method used [12].

Aspiration: Distal clavicle resection combined with antibiotics halted osteolysis in a documented case of Propionibacterium acnes–mediated distal clavicular osteolysis [1].

Other Considerations: Late loss of reduction was common in acromioclavicular joint dislocations, whereas clavicular resection reliably produced significant improvement in patients with persistent pain or posttraumatic arthritis [5]. Simple excision of the outer end of the clavicle yielded satisfactory results with no residual upward displacement disturbing patients in a cohort of seventy-three cases of complete dislocation and subluxation [7]. Methods to diagnose both superior and posterior translation of the clavicle require further debate [15]. Portal placement remains paramount in facilitating surgery and avoiding injury to adjacent extra-articular structures during distal clavicle resection [28].

Treatment

Non-Operative

The provided evidence does not explicitly detail conservative management protocols such as physical therapy, NSAIDs, or injections for distal clavicle osteolysis. However, the necessity of surgical intervention is established for appropriately selected patients with persistent symptoms [4].

Operative

Indications: Surgical resection is indicated to relieve symptoms in appropriately selected patients with persistent pain or posttraumatic arthritis following late loss of reduction after acromioclavicular (AC) joint dislocation [4, 5]. For chronic symptomatic AC joint injuries, partial claviculectomy is considered the optimal procedure due to negligible morbidity and rapid return to function [14]. Excision of the outer end of the clavicle is preferred for old AC joint dislocations, whereas open reduction and internal fixation are not recommended due to complications and poor functional results [13]. Total claviculectomy is a viable option for chronic clavicular dislocation, yielding excellent outcomes and high patient satisfaction [22]. Routine distal clavicle excision is not absolutely necessary in patients with symptomatic AC joint osteoarthritis undergoing arthroscopic rotator cuff repair [20].

Surgical Approach / Technique: Both open and arthroscopic distal clavicle resections are effective surgeries for recalcitrant AC joint pain, providing similarly good to excellent results regarding patient satisfaction and shoulder function at intermediate-term follow-up [49]. Patients undergoing arthroscopic distal clavicle excision via the direct approach can expect a faster return to activities compared with the open procedure while obtaining similar long-term outcomes [2]. Arthroscopic distal clavicle resection has provided more 'good or excellent' results than the open procedure, though this finding is comprised of low-level evidence [8]. Both approaches provide significant pain reduction at 1 year with no significant difference in outcome measures between groups, except for VAS pain score improvement [17]. Less residual pain was found using the arthroscopic technique compared with the open procedure for distal clavicle excision [49]. A well-performed distal clavicle excision will likely perform better than a poorly performed one, regardless of whether an open or arthroscopic approach is chosen [9].

Implant Selection: Acromioclavicular joint reconstruction with coracoacromial ligament transfer using the docking technique achieved excellent clinical results and decreased the risk of recurrent distal clavicle instability [23]. Satisfactory outcomes for fracture clavicle with acromioclavicular dislocation depend upon restoring the stability of the clavicle as well as the acromioclavicular joint [24]. Patients with displacement greater than 100% of the thickness of the distal clavicle had poorer postoperative clinical outcomes after AC joint dislocation treated with the endobutton device [6]. Simple excision of the outer end of the clavicle yielded satisfactory results in patients with AC joint dislocation, with no residual upward displacement disturbing the patients [7]. Ipsilateral os acromiale may be a relative contraindication to the clavicle hook plate [46].

Adjuncts: Subacromial osteolysis following hook plate fixation for AC dislocation has a relatively high and variable incidence, with the primary factor influencing the reported incidence being the radiological assessment method [12]. Distal clavicle fracture is a potential complication of misidentification of the AC joint and subsequent aggressive burring during shoulder arthroscopy [26].

Other Considerations: The combination of distal clavicle resection and antibiotics halted osteolysis in a case of Propionibacterium acnes–mediated distal clavicular osteolysis, with the patient remaining symptom-free at 10 months post-surgery [1]. High-level studies on treatment modalities for AC joint pain are limited [52].

Complications

Infection (PJI): Distal clavicle osteolysis mediated by Propionibacterium acnes can be halted by the combination of distal clavicle resection and antibiotics, with patients remaining symptom-free at 10 months post-surgery [1].

Instability: Horizontal instability of the clavicle is evident with distal clavicle resection of greater than 10 mm [11]. Incomplete excision and regrowth of the distal clavicle are the most common causes of revision following acromioclavicular joint resection [10]. Patients with displacement greater than 100% of the thickness of the distal clavicle had poorer postoperative clinical outcomes after acromioclavicular joint dislocation treated with the endobutton device [6]. Clavicular tunnel widening was observed in 70% of patients at final follow-up after coracoclavicular stabilization surgery, with a higher prevalence in chronic cases than in acute cases [16].

Other Considerations: Gorham-Stout disease should be considered in patients presenting with massive osteolysis after shoulder surgery [3]. Subacromial osteolysis following hook plate fixation for acromioclavicular dislocation has a relatively high and variable incidence, with the primary factor influencing reported incidence being the radiological assessment method [12]. The minimally invasive TightRope system showed reduced risk of subacromial distal clavicle osteolysis compared to the hook plate in the treatment of acute type III acromioclavicular dislocation [51]. Late loss of reduction was common following acromioclavicular joint dislocation treatment, though clavicular resection reliably produced significant improvement in patients with persistent pain or posttraumatic arthritis [5].

Recovery

Light activity (weeks): Patients undergoing arthroscopic distal clavicle excision via the direct approach can expect a faster return to activities compared with open procedures, while obtaining similar long-term outcomes [2]. For chronic symptomatic acromioclavicular joint injuries, partial claviculectomy is believed to be the best procedure, offering negligible morbidity and rapid return to function [14].

Full activity (months): Incomplete excision and regrowth of the distal clavicle are the most common causes of revision after acromioclavicular joint resection [10]. Total claviculectomy yielded good results for patients with chronic osteitis and malignancy but unsatisfying results for those with chronic posttraumatic pain, despite full range of motion being regained in all cases [27]. A majority of patients with untreated acute grade III acromioclavicular separation will do well without any formal treatment, though a small percentage may require delayed surgical intervention [56].

Complete recovery / outcome plateau (months): Late loss of reduction was common in patients with acromioclavicular joint dislocation, but clavicular resection reliably produced significant improvement in patients with persistent pain or posttraumatic arthritis [5]. Simple excision of the outer end of the clavicle yielded satisfactory results with no residual upward displacement disturbing patients in a cohort of seventy-three cases of complete dislocation and subluxation [7]. Fifteen years postoperatively, good clinical results persisted and anatomic reduction was overall maintained after arthroscopically assisted 2-bundle anatomic reduction of acute acromioclavicular joint separations, often with asymptomatic ossification of the coracoclavicular ligaments [19]. The short-term follow-up of 15 patients treated with minimally invasive coracoclavicular ligament augmentation using a flip button/polydioxanone repair revealed excellent radiologic and clinical results, with no subluxations or dislocations of the acromioclavicular joint noted [25].

Rehabilitation protocol: Satisfactory outcomes for fracture clavicle with acromioclavicular dislocation depend upon restoring the stability of the clavicle as well as the acromioclavicular joint [24]. Clavicular tunnel widening was observed in 70% of patients at final follow-up after coracoclavicular stabilization surgery, with a higher prevalence in chronic than in acute cases [16]. Although radiological assessment showed a statistically significant immediate superior clavicular displacement after hardware removal following ACJ stabilization using a suspensory fixation system, this may not negatively influence the results of ACJ stabilization in a clinically relevant way [18].

Functional milestones: Patients with displacement greater than 100% of the thickness of the distal clavicle had poorer postoperative clinical outcomes after acromioclavicular joint dislocation treated with the endobutton device [6].

Other Considerations: The combination of distal clavicle resection and antibiotics halted Propionibacterium acnes–mediated osteolysis, and the patient remained symptom free at 10 months after surgery [1].

Key Evidence

  • [Case_report] The combination of distal clavicle resection and antibiotics halted the osteolysis, and the patient has remained symptom free at 10 months after surgery. (10.1016/j.jse.2015.03.004)
  • [L3] Among patients undergoing distal clavicle excision for acromioclavicular joint pathology, those having an arthroscopic procedure, specifically through the direct approach, can expect a faster return to activities while obtaining similar long-term outcomes compared with the open procedure. (10.1016/j.arthro.2009.12.007)
  • [L4] The case highlights the need to consider this diagnosis in patients presenting with massive osteolysis after shoulder surgery. (10.1016/j.jse.2012.05.024)
  • [L5] In appropriately selected patients, open or arthroscopic distal clavicle resection is necessary to relieve symptoms. (10.5435/00124635-199905000-00004)
  • [L3] Late loss of reduction was common, and clavicular resection reliably produced significant improvement in patients with persistent pain or posttraumatic arthritis. (10.2106/00004623-198769070-00013)
  • [L3] Patients with displacement greater than 100% of the thickness of the distal clavicle had poorer postoperative clinical outcomes. (10.1186/s12891-025-09190-x)
  • [L3] Arthroscopic distal clavicle resection has provided more 'good or excellent' results than has the open procedure, but is comprised of low-level evidence. (10.1097/blo.0b013e31802f5450)
  • [L5] A well-performed distal clavicle excision will likely perform better than a poorly performed one, regardless of whether an open or arthroscopic approach is chosen. (10.1016/j.arthro.2018.03.004)
  • [L4] Incomplete excision and regrowth of the distal clavicle are the most common causes of revision. (10.1016/j.arthro.2009.06.010)
  • [L4] Horizontal instability of the clavicle is evident with distal clavicle resection of greater than 10 mm. (10.1016/j.xrrt.2021.05.003)
  • [L1] Subacromial osteolysis has a relatively high and variable incidence, and the primary factor influencing the reported incidence is the radiological assessment method. (10.1016/j.jse.2024.03.018)
  • [L4] Excision of the outer end of the clavicle is preferred for old dislocations, while open reduction and internal fixation are not recommended due to complications and poor functional results. (10.2106/00004623-196345080-00024)
  • [L4] Methods to diagnose both superior and posterior translation of the clavicle need further debate. (10.1016/j.jseint.2019.11.006)
  • [L1] Clavicular tunnel widening was observed in 70% of patients at final follow-up, with a higher prevalence in chronic than in acute cases. (10.1016/j.jse.2023.09.037)
  • [L1] Arthroscopic and open distal clavicle excisions both provide significant pain reduction at 1 year with no significant difference in outcome measures between groups, except for VAS pain score improvement. (10.1016/j.jse.2006.10.006)
  • [L4] Although radiological assessment showed a statistically significant immediate superior clavicular displacement after this rarely required procedure, with an increased incidence in the first year following stabilization, this may not negatively influence the results of ACJ stabilization in a clinically relevant way. (10.1007/s00167-022-06978-5)
  • [L3] Fifteen years postoperatively, good clinical results persisted and anatomic reduction was overall maintained, often with asymptomatic ossification of the coracoclavicular ligaments. (10.1177/03635465251355958)
  • [L2] Routine distal clavicle excision is not absolutely necessary, even in patients with symptomatic ACJ osteoarthritis. (10.1007/s00167-020-06098-y)
  • [Case_report] The case highlights that segmental fractures of the clavicle are easily missed. (10.1177/1758573214564496)
  • [Case_report] Total claviculectomy is a possible treatment option for chronic clavicular dislocation with excellent outcomes and high patient satisfaction. (10.1016/j.xrrt.2021.03.007)
  • [L4] Excellent clinical results were achieved, decreasing the risk of recurrent distal clavicle instability. (10.1186/1471-2474-10-6)
  • [L4] Satisfactory outcome depends upon restoring the stability of the clavicle as well as the acromioclavicular joint. (10.1111/j.1758-5740.2010.00102.x)
  • [L4] The short-term follow-up of 15 recently operated patients reveals excellent radiologic and clinical results, with no subluxations or dislocations of the acromioclavicular joint noted. (10.1016/j.arthro.2006.12.015)
  • [L4] Distal clavicle fracture is a potential complication of misidentification of the AC joint and subsequent aggressive burring during shoulder arthroscopy. (10.1016/j.arthro.2009.02.008)
  • [L4] Total claviculectomy yielded good results for patients with chronic osteitis and malignancy but unsatisfying results for those with chronic posttraumatic pain, despite full range of motion being regained in all cases. (10.1016/j.jse.2006.07.007)
  • [Case_report] Regardless of the technique chosen for distal clavicle resection, portal placement remains paramount in both facilitating surgery and avoiding injury to adjacent extra-articular structures. (10.1016/j.jse.2010.08.032)
  • [L5] Despite technology innovations, a precise, easy to use and low-cost non-invasive method able to draw and analyze the kinematics of the shoulder complex has not been developed yet. (10.1177/17585732221090226)
  • [L5] This study provided normative kinematic values of scapulothoracic movements in the shoulder girdle. (10.1016/j.jseint.2022.09.014)
  • [L5] Although each technique was able to restore different elements of the joint kinematics, none of the strategies completely restored the shoulder girdle to its preinjured state. (10.1177/03635465221095231)
  • [L5] The trapezoid and conoid ligaments have unique functions in normal shoulder kinematics because of their anatomic attachments. (10.1016/j.arthro.2009.12.031)
  • [L5] The kinematic changes could be a potential source of pain and dysfunction in the shoulder with AC joint dislocation. (10.1177/0363546512458571)
  • [L5] Scapular and clavicular kinematics were affected in AC separation models. (10.1016/j.jse.2013.01.004)
  • [L5] A comprehensive clinical approach emphasizing the evaluation of the extent of the anatomic injury and understanding its mechanical consequences regarding shoulder and arm function is a key in the development of guidelines for developing operative or non-operative treatment protocols and for establishing outcomes of the treatment protocols. (10.1177/17585732221122335)
  • [L4] The inconsistency of AC joint testing parameters and the lack of thorough translation studies indicate a necessity for increased attention in the overall assessment of shoulder stability to close the gap in the foundational biomechanical research. (10.1016/j.xrrt.2024.06.009)
  • [L5] Anatomically, it provides sufficient tissue length, excursion, and width, and biomechanically, it is as strong as the coracoacromial ligament. (10.1016/j.jse.2006.09.007)
  • [L5] No significant biomechanical differences in displacement or stiffness were seen between the anatomical landmark technique and the coracoid-based landmarks technique. (10.1177/23259671221132541)
  • [L5] New surgical techniques continue to evolve as more biomechanical data emerge and kinematic understanding improves. (10.5435/jaaos-d-16-00776)
  • [L5] By exploring emerging concepts and strategies regarding horizontal and rotational instability and scapular biomechanics, the article aims to lay the foundation for future studies aimed at improving treatment outcomes and patient management. (10.1016/j.jseint.2023.11.018)
  • [L4] Preliminary findings revealed no detectable differences between surgically reconstructed and uninjured sides in ACJ biomechanics, range of motion, and isometric strength, while nonoperatively treated shoulders showed increased internal rotation, upward rotation, and posterior tilting. (10.1177/23259671241274707)
  • [L4] Type I and II acromioclavicular joint disruptions impair long-term shoulder function in about half of patients 10 years after injury. (10.1177/0363546508319047)
  • [L5] At 150 to 200 N of loading, CAL excision and acromioplasty increase the rotator cuff force required to maintain normal glenohumeral biomechanics by 25% to 30%. (10.1016/j.jse.2015.10.022)
  • [L3] Centre of pressure measurement detected sensorimotor functional deficits following surgical treatment of the shoulder joint in patients with confirmed successful clinical and functional outcomes. (10.1007/s00167-021-06751-0)
  • [L4] Ipsilateral os acromiale may be a relative contraindication to the clavicle hook plate. (10.1186/s12891-021-04841-1)
  • [L4] Weighted stress radiographs significantly increased the measured elevation of the clavicle and the coracoclavicular distance compared to non-weighted views. (10.1016/j.jseint.2023.06.011)
  • [L3] Open and arthroscopic distal clavicle excision are both effective surgeries to treat recalcitrant acromioclavicular joint pain, providing similarly good to excellent results regarding patient satisfaction and shoulder function at intermediate-term follow-up, though less residual pain was found using the arthroscopic technique. (10.1177/0363546511419633)
  • [L5] The ISAKOS Upper Extremity Committee suggests adding grade IIIA and grade IIIB injuries to a modified Rockwood classification to distinguish between stable type III injuries and unstable grade III injuries with therapy-resistant scapular dysfunction and overriding clavicle. (10.1016/j.arthro.2013.11.005)
  • [L3] However, the minimally invasive TightRope system showed further benefits such as reduced reoperation for implant removal and reduced risk of subacromial distal clavicle osteolysis. (10.1155/2022/8706638)
  • [L2] High-level studies on treatment modalities for acromio-clavicular joint pain are limited. (10.1177/1758573217700839)
  • [L4] A high index of suspicion is needed to diagnose such complications early before irretrievable bone loss to osteolysis. (10.1111/sae.12035)
  • [L2] A majority of patients with untreated acute grade III acromioclavicular separation will do well without any formal treatment, though a small percentage may require delayed surgical intervention. (10.1177/03635465010290060401)

See Also

References

[1] Propionibacterium acnes–mediated distal clavicular osteolysis: a case report. Journal of Shoulder and Elbow Surgery. 2015. DOI: 10.1016/j.jse.2015.03.004

[2] Open Versus Arthroscopic Distal Clavicle Resection. Arthroscopy. 2010. DOI: 10.1016/j.arthro.2009.12.007

[3] Gorham-Stout disease as a complication of posterior shoulder capsulorrhaphy. Journal of Shoulder and Elbow Surgery. 2012. DOI: 10.1016/j.jse.2012.05.024

[4] Painful Conditions of the Acromioclavicular Joint. Journal of the American Academy of Orthopaedic Surgeons. 1999. DOI: 10.5435/00124635-199905000-00004

[5] Dislocation of the acromioclavicular joint. An end-result study.. The Journal of Bone & Joint Surgery. 1987. DOI: 10.2106/00004623-198769070-00013

[6] Predicting reduction loss risk after acromioclavicular joint dislocation treated with the endobutton device. BMC Musculoskeletal Disorders. 2025. DOI: 10.1186/s12891-025-09190-x

[7] Complete Dislocation and Subluxation of the Acromioclavicular Joint: End Result in Seventy-three Cases.. The Journal of Bone and Joint Surgery. American Volume. 1961.

[8] Surgical Treatment of Symptomatic Acromioclavicular Joint Problems. Clinical Orthopaedics and Related Research. 2007. DOI: 10.1097/blo.0b013e31802f5450

[9] Editorial Commentary: The “Mumford” & Sons: For Distal Clavicle Excisions, What Are Our Young Surgeons Doing, and How Well Are They Doing It?. Arthroscopy. 2018. DOI: 10.1016/j.arthro.2018.03.004

[10] Open Versus Arthroscopic Acromioclavicular Joint Resection: A Retrospective Comparison Study. Arthroscopy. 2009. DOI: 10.1016/j.arthro.2009.06.010

[11] The reverse coracoacromial ligament transfer for “horizontal” acromioclavicular joint instability. JSES Reviews, Reports, and Techniques. 2021. DOI: 10.1016/j.xrrt.2021.05.003

[12] Subacromial osteolysis following hook plate fixation for acromioclavicular dislocation: a systematic review and meta-analysis. Journal of Shoulder and Elbow Surgery. 2024. DOI: 10.1016/j.jse.2024.03.018

[13] COMPLETE DISLOCATION OF THE ACROMIOCLAVICULAR JOINT. The Journal of Bone & Joint Surgery. 1963. DOI: 10.2106/00004623-196345080-00024

[14] Acromioclavicular-Joint Injury: AN END-RESULT STUDY.. The Journal of Bone and Joint Surgery. American Volume. 1966.

[15] Methods used to assess the severity of acromioclavicular joint separations in Japan: a survey. JSES International. 2020. DOI: 10.1016/j.jseint.2019.11.006

[16] Clavicular tunnel widening after coracoclavicular stabilization surgery: a systematic review and meta-analysis. Journal of Shoulder and Elbow Surgery. 2024. DOI: 10.1016/j.jse.2023.09.037

[17] Arthroscopic versus open distal clavicle excision: Comparative results at six months and one year from a randomized, prospective clinical trial. Journal of Shoulder and Elbow Surgery. 2007. DOI: 10.1016/j.jse.2006.10.006

[18] Low rate of substantial loss of reduction immediately after hardware removal following acromioclavicular joint stabilization using a suspensory fixation system. Knee Surgery, Sports Traumatology, Arthroscopy. 2022. DOI: 10.1007/s00167-022-06978-5

[19] Long-term Follow-up After Arthroscopically Assisted 2-Bundle Anatomic Reduction of Acute Acromioclavicular Joint Separations. The American Journal of Sports Medicine. 2025. DOI: 10.1177/03635465251355958

[20] Acromioclavicular joint arthritis is not an indication for routine distal clavicle excision in arthroscopic rotator cuff repair. Knee Surgery, Sports Traumatology, Arthroscopy. 2020. DOI: 10.1007/s00167-020-06098-y

[21] Segmental clavicle fracture and acromio-clavicular joint disruption: an unusual case report. Shoulder & Elbow. 2014. DOI: 10.1177/1758573214564496

[22] A four-year-old neglected traumatic bipolar clavicular dislocation: a case report. JSES Reviews, Reports, and Techniques. 2021. DOI: 10.1016/j.xrrt.2021.03.007

[23] Acromioclavicular joint reconstruction with coracoacromial ligament transfer using the docking technique. BMC Musculoskeletal Disorders. 2009. DOI: 10.1186/1471-2474-10-6

[24] Fracture Clavicle with Acromioclavicular Dislocation: A Complex Injury. Shoulder & Elbow. 2011. DOI: 10.1111/j.1758-5740.2010.00102.x

[25] Minimally Invasive Coracoclavicular Ligament Augmentation With a Flip Button/Polydioxanone Repair for Treatment of Total Acromioclavicular Joint Dislocation. Arthroscopy. 2007. DOI: 10.1016/j.arthro.2006.12.015

[26] Distal Clavicle Fracture as a Complication of Arthroscopic Distal Clavicle Resection. Arthroscopy. 2009. DOI: 10.1016/j.arthro.2009.02.008

[27] Outcome of total claviculectomy in six cases. Journal of Shoulder and Elbow Surgery. 2007. DOI: 10.1016/j.jse.2006.07.007

[28] Acromioclavicular dislocation after arthroscopic distal clavicle resection: a case report. Journal of Shoulder and Elbow Surgery. 2011. DOI: 10.1016/j.jse.2010.08.032

[29] Evaluation of the range of motion of scapulothoracic, acromioclavicular and sternoclavicular joints: State of the art. Shoulder & Elbow. 2022. DOI: 10.1177/17585732221090226

[30] Kinematic analysis of scapulothoracic movements in the shoulder girdle: a whole cadaver study. JSES International. 2023. DOI: 10.1016/j.jseint.2022.09.014

[31] Differences between Coracoclavicular, Acromioclavicular, or Combined Reconstruction Techniques on the Kinematics of the Shoulder Girdle. The American Journal of Sports Medicine. 2022. DOI: 10.1177/03635465221095231

[32] A Biomechanical Analysis of the Native Coracoclavicular Ligaments and Their Influence on a New Reconstruction Using a Coracoid Tunnel and Free Tendon Graft. Arthroscopy. 2010. DOI: 10.1016/j.arthro.2009.12.031

[33] The Function of the Acromioclavicular and Coracoclavicular Ligaments in Shoulder Motion. The American Journal of Sports Medicine. 2012. DOI: 10.1177/0363546512458571

[34] Acromioclavicular joint ligamentous system contributing to clavicular strut function: a cadaveric study. Journal of Shoulder and Elbow Surgery. 2013. DOI: 10.1016/j.jse.2013.01.004

[35] Acromioclavicular joint injuries revisited: Pathoanatomy, pathomechanics, and clinical presentation. Shoulder & Elbow. 2022. DOI: 10.1177/17585732221122335

[36] Acromioclavicular joint biomechanics: a systematic review. JSES Reviews, Reports, and Techniques. 2024. DOI: 10.1016/j.xrrt.2024.06.009

[37] Anatomy of the pectoralis minor tendon and its use in acromioclavicular joint reconstruction. Journal of Shoulder and Elbow Surgery. 2007. DOI: 10.1016/j.jse.2006.09.007

[38] Comparing the Anatomical Landmarks Versus the Coracoid-Based Landmarks Techniques for Coracoclavicular Stabilization After High-Grade Acromioclavicular Injury: A Biomechanical Study. Orthopaedic Journal of Sports Medicine. 2022. DOI: 10.1177/23259671221132541

[39] Challenges in Treating Acromioclavicular Separations: Current Concepts. Journal of the American Academy of Orthopaedic Surgeons. 2018. DOI: 10.5435/jaaos-d-16-00776

[40] Current trends in surgical treatment of the acromioclavicular joint injuries in 2023: a review of the literature. JSES International. 2024. DOI: 10.1016/j.jseint.2023.11.018

[41] Using Dynamic Stereo X-ray Imaging for In Vivo Acromioclavicular Joint Kinematics Assessment: A Preliminary Investigation. Orthopaedic Journal of Sports Medicine. 2024. DOI: 10.1177/23259671241274707

[43] Long-Term Shoulder Function after Type I and II Acromioclavicular Joint Disruption. The American Journal of Sports Medicine. 2008. DOI: 10.1177/0363546508319047

[44] The effect of coracoacromial ligament excision and acromioplasty on the amount of rotator cuff force production necessary to restore intact glenohumeral biomechanics. Journal of Shoulder and Elbow Surgery. 2016. DOI: 10.1016/j.jse.2015.10.022

[45] Center of pressure (COP) measurement in patients with confirmed successful outcomes following shoulder surgery show significant sensorimotor deficits. Knee Surgery, Sports Traumatology, Arthroscopy. 2021. DOI: 10.1007/s00167-021-06751-0

[46] Os acromiale may be a contraindication of the clavicle hook plate: case reports and literature review. BMC Musculoskeletal Disorders. 2021. DOI: 10.1186/s12891-021-04841-1

[47] Position of scapula and clavicle in acute acromioclavicular joint dislocations: depressed scapula or elevated distal clavicle?. JSES International. 2023. DOI: 10.1016/j.jseint.2023.06.011

[49] Arthroscopic Versus Open Distal Clavicle Excision. The American Journal of Sports Medicine. 2011. DOI: 10.1177/0363546511419633

[50] ISAKOS Upper Extremity Committee Consensus Statement on the Need for Diversification of the Rockwood Classification for Acromioclavicular Joint Injuries. Arthroscopy. 2014. DOI: 10.1016/j.arthro.2013.11.005

[51] Comparison of the Hook Plate versus TightRope System in the Treatment of Acute Type III Acromioclavicular Dislocation. Advances in Orthopedics. 2022. DOI: 10.1155/2022/8706638

[52] Managing acromio-clavicular joint pain: a scoping review. Shoulder & Elbow. 2017. DOI: 10.1177/1758573217700839

[54] Bone Osteolysis Following Acromioclavicular Joint Reconstruction Using Synthetic Ligament (Surgilig™). Shoulder & Elbow. 2014. DOI: 10.1111/sae.12035

[56] A Prospective Evaluation of Untreated Acute Grade III Acromioclavicular Separations. The American Journal of Sports Medicine. 2001. DOI: 10.1177/03635465010290060401

Creative Commons BY-NC 4.0

CC Creative Commons licence
BY Attribution — you must credit the source
NC NonCommercial — not for commercial use

Attribution-NonCommercial 4.0 International

Creative Commons Corporation ("Creative Commons") is not a law firm and does not provide legal services or legal advice. Distribution of Creative Commons public licenses does not create a lawyer-client or other relationship. Creative Commons makes its licenses and related information available on an "as-is" basis. Creative Commons gives no warranties regarding its licenses, any material licensed under their terms and conditions, or any related information. Creative Commons disclaims all liability for damages resulting from their use to the fullest extent possible.

Using Creative Commons Public Licenses

Creative Commons public licenses provide a standard set of terms and conditions that creators and other rights holders may use to share original works of authorship and other material subject to copyright and certain other rights specified in the public license below. The following considerations are for informational purposes only, are not exhaustive, and do not form part of our licenses.

Considerations for licensors: Our public licenses are intended for use by those authorized to give the public permission to use material in ways otherwise restricted by copyright and certain other rights. Our licenses are irrevocable. Licensors should read and understand the terms and conditions of the license they choose before applying it. Licensors should also secure all rights necessary before applying our licenses so that the public can reuse the material as expected. Licensors should clearly mark any material not subject to the license. This includes other CC- licensed material, or material used under an exception or limitation to copyright. More considerations for licensors: wiki.creativecommons.org/Considerations_for_licensors

Considerations for the public: By using one of our public licenses, a licensor grants the public permission to use the licensed material under specified terms and conditions. If the licensor's permission is not necessary for any reason--for example, because of any applicable exception or limitation to copyright--then that use is not regulated by the license. Our licenses grant only permissions under copyright and certain other rights that a licensor has authority to grant. Use of the licensed material may still be restricted for other reasons, including because others have copyright or other rights in the material. A licensor may make special requests, such as asking that all changes be marked or described. Although not required by our licenses, you are encouraged to respect those requests where reasonable. More considerations for the public: wiki.creativecommons.org/Considerations_for_licensees

Creative Commons Attribution-NonCommercial 4.0 International Public License

By exercising the Licensed Rights (defined below), You accept and agree to be bound by the terms and conditions of this Creative Commons Attribution-NonCommercial 4.0 International Public License ("Public License"). To the extent this Public License may be interpreted as a contract, You are granted the Licensed Rights in consideration of Your acceptance of these terms and conditions, and the Licensor grants You such rights in consideration of benefits the Licensor receives from making the Licensed Material available under these terms and conditions.

Section 1 -- Definitions.

a. Adapted Material means material subject to Copyright and Similar Rights that is derived from or based upon the Licensed Material and in which the Licensed Material is translated, altered, arranged, transformed, or otherwise modified in a manner requiring permission under the Copyright and Similar Rights held by the Licensor. For purposes of this Public License, where the Licensed Material is a musical work, performance, or sound recording, Adapted Material is always produced where the Licensed Material is synched in timed relation with a moving image.

b. Adapter's License means the license You apply to Your Copyright and Similar Rights in Your contributions to Adapted Material in accordance with the terms and conditions of this Public License.

c. Copyright and Similar Rights means copyright and/or similar rights closely related to copyright including, without limitation, performance, broadcast, sound recording, and Sui Generis Database Rights, without regard to how the rights are labeled or categorized. For purposes of this Public License, the rights specified in Section 2(b)(1)-(2) are not Copyright and Similar Rights.

d. Effective Technological Measures means those measures that, in the absence of proper authority, may not be circumvented under laws fulfilling obligations under Article 11 of the WIPO Copyright Treaty adopted on December 20, 1996, and/or similar international agreements.

e. Exceptions and Limitations means fair use, fair dealing, and/or any other exception or limitation to Copyright and Similar Rights that applies to Your use of the Licensed Material.

f. Licensed Material means the artistic or literary work, database, or other material to which the Licensor applied this Public License.

g. Licensed Rights means the rights granted to You subject to the terms and conditions of this Public License, which are limited to all Copyright and Similar Rights that apply to Your use of the Licensed Material and that the Licensor has authority to license.

h. Licensor means the individual(s) or entity(ies) granting rights under this Public License.

i. NonCommercial means not primarily intended for or directed towards commercial advantage or monetary compensation. For purposes of this Public License, the exchange of the Licensed Material for other material subject to Copyright and Similar Rights by digital file-sharing or similar means is NonCommercial provided there is no payment of monetary compensation in connection with the exchange.

j. Share means to provide material to the public by any means or process that requires permission under the Licensed Rights, such as reproduction, public display, public performance, distribution, dissemination, communication, or importation, and to make material available to the public including in ways that members of the public may access the material from a place and at a time individually chosen by them.

k. Sui Generis Database Rights means rights other than copyright resulting from Directive 96/9/EC of the European Parliament and of the Council of 11 March 1996 on the legal protection of databases, as amended and/or succeeded, as well as other essentially equivalent rights anywhere in the world.

l. You means the individual or entity exercising the Licensed Rights under this Public License. Your has a corresponding meaning.

Section 2 -- Scope.

a. License grant.

1. Subject to the terms and conditions of this Public License, the Licensor hereby grants You a worldwide, royalty-free, non-sublicensable, non-exclusive, irrevocable license to exercise the Licensed Rights in the Licensed Material to:

a. reproduce and Share the Licensed Material, in whole or in part, for NonCommercial purposes only; and

b. produce, reproduce, and Share Adapted Material for NonCommercial purposes only.

2. Exceptions and Limitations. For the avoidance of doubt, where Exceptions and Limitations apply to Your use, this Public License does not apply, and You do not need to comply with its terms and conditions.

3. Term. The term of this Public License is specified in Section 6(a).

4. Media and formats; technical modifications allowed. The Licensor authorizes You to exercise the Licensed Rights in all media and formats whether now known or hereafter created, and to make technical modifications necessary to do so. The Licensor waives and/or agrees not to assert any right or authority to forbid You from making technical modifications necessary to exercise the Licensed Rights, including technical modifications necessary to circumvent Effective Technological Measures. For purposes of this Public License, simply making modifications authorized by this Section 2(a) (4) never produces Adapted Material.

5. Downstream recipients.

a. Offer from the Licensor -- Licensed Material. Every recipient of the Licensed Material automatically receives an offer from the Licensor to exercise the Licensed Rights under the terms and conditions of this Public License.

b. No downstream restrictions. You may not offer or impose any additional or different terms or conditions on, or apply any Effective Technological Measures to, the Licensed Material if doing so restricts exercise of the Licensed Rights by any recipient of the Licensed Material.

6. No endorsement. Nothing in this Public License constitutes or may be construed as permission to assert or imply that You are, or that Your use of the Licensed Material is, connected with, or sponsored, endorsed, or granted official status by, the Licensor or others designated to receive attribution as provided in Section 3(a)(1)(A)(i).

b. Other rights.

1. Moral rights, such as the right of integrity, are not licensed under this Public License, nor are publicity, privacy, and/or other similar personality rights; however, to the extent possible, the Licensor waives and/or agrees not to assert any such rights held by the Licensor to the limited extent necessary to allow You to exercise the Licensed Rights, but not otherwise.

2. Patent and trademark rights are not licensed under this Public License.

3. To the extent possible, the Licensor waives any right to collect royalties from You for the exercise of the Licensed Rights, whether directly or through a collecting society under any voluntary or waivable statutory or compulsory licensing scheme. In all other cases the Licensor expressly reserves any right to collect such royalties, including when the Licensed Material is used other than for NonCommercial purposes.

Section 3 -- License Conditions.

Your exercise of the Licensed Rights is expressly made subject to the following conditions.

a. Attribution.

1. If You Share the Licensed Material (including in modified form), You must:

a. retain the following if it is supplied by the Licensor with the Licensed Material:

i. identification of the creator(s) of the Licensed Material and any others designated to receive attribution, in any reasonable manner requested by the Licensor (including by pseudonym if designated);

ii. a copyright notice;

iii. a notice that refers to this Public License;

iv. a notice that refers to the disclaimer of warranties;

v. a URI or hyperlink to the Licensed Material to the extent reasonably practicable;

b. indicate if You modified the Licensed Material and retain an indication of any previous modifications; and

c. indicate the Licensed Material is licensed under this Public License, and include the text of, or the URI or hyperlink to, this Public License.

2. You may satisfy the conditions in Section 3(a)(1) in any reasonable manner based on the medium, means, and context in which You Share the Licensed Material. For example, it may be reasonable to satisfy the conditions by providing a URI or hyperlink to a resource that includes the required information.

3. If requested by the Licensor, You must remove any of the information required by Section 3(a)(1)(A) to the extent reasonably practicable.

4. If You Share Adapted Material You produce, the Adapter's License You apply must not prevent recipients of the Adapted Material from complying with this Public License.

Section 4 -- Sui Generis Database Rights.

Where the Licensed Rights include Sui Generis Database Rights that apply to Your use of the Licensed Material:

a. for the avoidance of doubt, Section 2(a)(1) grants You the right to extract, reuse, reproduce, and Share all or a substantial portion of the contents of the database for NonCommercial purposes only;

b. if You include all or a substantial portion of the database contents in a database in which You have Sui Generis Database Rights, then the database in which You have Sui Generis Database Rights (but not its individual contents) is Adapted Material; and

c. You must comply with the conditions in Section 3(a) if You Share all or a substantial portion of the contents of the database.

For the avoidance of doubt, this Section 4 supplements and does not replace Your obligations under this Public License where the Licensed Rights include other Copyright and Similar Rights.

Section 5 -- Disclaimer of Warranties and Limitation of Liability.

a. UNLESS OTHERWISE SEPARATELY UNDERTAKEN BY THE LICENSOR, TO THE EXTENT POSSIBLE, THE LICENSOR OFFERS THE LICENSED MATERIAL AS-IS AND AS-AVAILABLE, AND MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND CONCERNING THE LICENSED MATERIAL, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHER. THIS INCLUDES, WITHOUT LIMITATION, WARRANTIES OF TITLE, MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, ABSENCE OF LATENT OR OTHER DEFECTS, ACCURACY, OR THE PRESENCE OR ABSENCE OF ERRORS, WHETHER OR NOT KNOWN OR DISCOVERABLE. WHERE DISCLAIMERS OF WARRANTIES ARE NOT ALLOWED IN FULL OR IN PART, THIS DISCLAIMER MAY NOT APPLY TO YOU.

b. TO THE EXTENT POSSIBLE, IN NO EVENT WILL THE LICENSOR BE LIABLE TO YOU ON ANY LEGAL THEORY (INCLUDING, WITHOUT LIMITATION, NEGLIGENCE) OR OTHERWISE FOR ANY DIRECT, SPECIAL, INDIRECT, INCIDENTAL, CONSEQUENTIAL, PUNITIVE, EXEMPLARY, OR OTHER LOSSES, COSTS, EXPENSES, OR DAMAGES ARISING OUT OF THIS PUBLIC LICENSE OR USE OF THE LICENSED MATERIAL, EVEN IF THE LICENSOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSSES, COSTS, EXPENSES, OR DAMAGES. WHERE A LIMITATION OF LIABILITY IS NOT ALLOWED IN FULL OR IN PART, THIS LIMITATION MAY NOT APPLY TO YOU.

c. The disclaimer of warranties and limitation of liability provided above shall be interpreted in a manner that, to the extent possible, most closely approximates an absolute disclaimer and waiver of all liability.

Section 6 -- Term and Termination.

a. This Public License applies for the term of the Copyright and Similar Rights licensed here. However, if You fail to comply with this Public License, then Your rights under this Public License terminate automatically.

b. Where Your right to use the Licensed Material has terminated under Section 6(a), it reinstates:

1. automatically as of the date the violation is cured, provided it is cured within 30 days of Your discovery of the violation; or

2. upon express reinstatement by the Licensor.

For the avoidance of doubt, this Section 6(b) does not affect any right the Licensor may have to seek remedies for Your violations of this Public License.

c. For the avoidance of doubt, the Licensor may also offer the Licensed Material under separate terms or conditions or stop distributing the Licensed Material at any time; however, doing so will not terminate this Public License.

d. Sections 1, 5, 6, 7, and 8 survive termination of this Public License.

Section 7 -- Other Terms and Conditions.

a. The Licensor shall not be bound by any additional or different terms or conditions communicated by You unless expressly agreed.

b. Any arrangements, understandings, or agreements regarding the Licensed Material not stated herein are separate from and independent of the terms and conditions of this Public License.

Section 8 -- Interpretation.

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.

Creative Commons may be contacted at creativecommons.org.