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远端锁骨骨溶解

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Updated Aug 2026
图中展示了一个人在健身房进行卧推，肩部顶端出现疼痛。
远端锁骨骨溶解（举重者肩）引起肩部顶部的疼痛，典型表现为在进行推压类动作时出现疼痛。 Kieran Hirpara 4.0

本页面由机器翻译，尚未经临床医生审核。英文版本为权威版本。

您的感受

您可能会在肩膀的最顶端感到疼痛，即锁骨与肩胛骨相接的地方。这个部位被称为肩锁关节。这种酸痛可能始于您举起重物或进行重复性的过头运动之后。随着时间的推移，锁骨末端的骨骼可能会磨损或溶解。这种情况被称为锁骨远端骨溶解。

疼痛通常在日常活动中加剧。当您伸手穿过身体将衬衫塞进裤子时，可能会感到尖锐的刺痛。在背后扣上胸罩可能会变得困难且疼痛。将物体举过头顶（例如将包放在高架子上）可能会引发深层酸痛。即使是简单的动作，如伸手去拉安全带，也可能刺激关节。

夜间疼痛很常见。您可能发现很难在患侧侧卧睡觉。身体重量压在发炎的关节上可能会将您痛醒。一些患者报告早晨刚醒来时感到僵硬。这种僵硬通常在活动后会缓解，但活动后疼痛会再次出现。

如果您以前做过肩部手术，症状可能会更复杂。有时，骨丢失是先前手术的并发症。在极少数情况下，痤疮丙酸杆菌（Propionibacterium acnes）等细菌感染会导致显著的骨丢失。这种类型的骨溶解可能需要特定的治疗来阻止骨骼进一步溶解。

您可能还会注意到肩部不稳定。如果关节松弛，您在移动时锁骨可能会移位。这可能会让您感觉肩膀要脱臼。如果移除或丢失了超过 10 毫米的骨骼，锁骨的水平移动会变得明显。这种不稳定性会使举起重物变得更加困难。

并非所有患有关节磨损性关节炎的患者都需要手术。一些患者通过休息和药物来管理症状。然而，如果疼痛持续存在并限制您的日常生活，您的外科医生可能会讨论切除锁骨末端。这种称为锁骨远端切除术的手术可以减轻关节压力。它通常用于经保守治疗无效的慢性疼痛。

实际发生了什么

您的锁骨与肩胛骨在肩部顶端附近的一个小关节处相接。可以将此关节视为减震器，使您的手臂能够自由运动。随着时间的推移，磨损和撕裂会损伤骨端的平滑涂层。这种情况称为骨关节炎。身体可能会通过分解锁骨的最末端来做出反应，这一过程称为骨溶解。当您横过身体移动手臂或举起重物过头顶时，这会导致炎症和疼痛。

有时，这个问题是由损伤引起的。您可能拉伤或撕裂了固定锁骨的韧带。这些韧带像强绳一样保持骨骼对齐。当它们受损时，关节力学会发生变化。您的肩胛骨和锁骨可能无法平滑地一起运动。这种不匹配会导致研磨感、僵硬和酸痛。即使初始损伤看似轻微，改变的运动模式也可能导致长期不适。约有一半患有某些类型肩关节紊乱的患者在十年后出现功能受损。

在极少数情况下，低度感染可导致这种骨质破坏。细菌可能定植于关节内，触发身体分解骨组织。如果发生这种情况，切除受损的骨端并使用抗生素可以阻止该过程。对于大多数人来说，疼痛源于关节表面相互摩擦或韧带被过度拉伸。

您的外科医生将评估受影响的骨骼范围以及您的肩关节运动情况。如果休息和理疗无效，切除锁骨的受损末端可以缓解疼痛。此手术为骨骼运动创造了更多空间，避免研磨。对于患有持续性疼痛或关节炎的患者，这是一种改善舒适度的可靠方法。目标是恢复平滑运动并减少限制您日常活动的炎症。

我们能采取的措施

我们针对远端锁骨骨溶解症所采用的方法，反映了 Mater Private Hospital Rockhampton 上肢外科医生 Kieran Hirpara 博士在我们诊所管理该病症的方式。患者通过全科医生或物理治疗师的转诊来到我们的诊所。我们首先进行全面评估，包括病史采集、体格检查以及必要时进行影像学检查。对于退行性或长期存在的问题，我们通常从非手术治疗开始。这为您的身体提供了平息炎症的时间，并增强肩部力量以支持关节。

您可以从改变引起疼痛的活动开始。在一段时间内避免提重物或过头运动。物理治疗旨在改善您的肩部稳定性和活动范围。我们通常建议在进行其他选择之前，先充分尝试这种保守治疗方法。如果疼痛持续存在，我们可能会讨论药物治疗。这包括使用止痛药和抗炎药来减轻肿胀。我们还可能提供注射治疗，如可的松，以直接使关节镇静。这些治疗有助于管理症状，但不能逆转骨质流失。

当保守治疗未能带来足够改善时，会考虑手术治疗。最常见的术式是远端锁骨切除术，即切除受损的锁骨末端。通过防止骨头相互摩擦来缓解疼痛。与开放手术相比，关节镜切除术后能更快地恢复活动，同时提供相似的长期结果。在慢性不稳定的情况下，我们可能会使用您自身的韧带重建关节。对于严重且长期的脱位，完全切除锁骨末端是一个可获得高患者满意度的选择。我们会与您讨论这些选项，以确保计划符合您的具体需求和目标。

预期情况

远端锁骨骨质溶解是一种磨损性疾病，表现为锁骨末端骨质破坏。这通常会导致肩部持续性疼痛。如果您有未经治疗的急性损伤，大多数患者无需任何正式治疗即可恢复良好。然而，一小部分患者若症状持续，可能需要延迟进行手术干预。

当症状无法自行缓解时，您的外科医生可能会建议切除锁骨的外侧端。该手术对于持续性疼痛或创伤后关节炎患者，能可靠地产生显著改善。与开放手术相比，关节镜手术可使患者更快恢复活动，同时获得相似的长期结果。两种术式在术后1年均能显著减轻疼痛。

恢复过程是渐进的。短期内，您可能会注意到功能迅速恢复，且并发症极少。长期来看，良好的临床结果可维持多年。术后15年，解剖复位通常得以维持，尽管部分患者可能在韧带附近出现无症状的骨质增生。

重要的是要理解，预后存在差异。骨质切除不彻底是翻修手术最常见的原因。如果残留骨质超过10毫米，可能会出现水平不稳定。术前移位严重的患者，其临床结果可能较差。锁骨末端的完全切除通常仅保留给特定病例，如慢性感染或恶性肿瘤，因为尽管它能恢复完全的活动度，但可能无法有效缓解创伤后疼痛。

如果您的情况由特定细菌引起，骨切除联合抗生素治疗可以阻止病情进展。在这种情况下，患者在术后10个月保持无症状。若不进行治疗，关节脱位后晚期复位丢失很常见。通过适当的管理，您可以预期磨擦痛得到缓解，肩部稳定性得到改善。您的外科医生将帮助您判断这一治疗方案是否适合您的具体损伤。

何时就医

如果肩部疼痛在休息后未改善，请咨询您的全科医生。如果您感到关节无力或不稳定，请要求专科医生进行评估。注意观察肩部锁定或感觉肩部脱位的情况。这些症状可能会干扰睡眠或工作。疼痛突然加重也是寻求医疗帮助的理由。您的外科医生将检查是否存在骨质改变或不稳定等问题。例如，去除超过 10 毫米的骨质可能导致水平方向的不稳定。骨质去除不彻底可能导致骨质再生并需要进一步手术。早期评估有助于有效管理这些风险。

Reviewed by Dr Kieran Hirpara · 7 August 2026.

Want the clinical detail? Read the clinician version.

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Evidence & references

This is the clinical evidence summary written for health professionals. It is technical, and it lists the research this page was built from. You do not need to read it to understand your treatment or to make a decision about it.

Overview

  • Distal clavicle resection combined with 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].
  • Patients undergoing arthroscopic distal clavicle excision via the direct approach for acromioclavicular joint pathology can expect a faster return to activities compared with the open procedure, while obtaining similar long-term outcomes [2].
  • Open or arthroscopic distal clavicle resection is necessary to relieve symptoms in appropriately selected patients [4].
  • Late loss of reduction was common in acromioclavicular joint dislocations, but clavicular resection reliably produced significant improvement in patients with persistent pain or posttraumatic arthritis [5].
  • 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].
  • 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].
  • Excision of the outer end of the clavicle is preferred for old acromioclavicular joint dislocations, while open reduction and internal fixation are not recommended due to complications and poor functional results [13].
  • For chronic symptomatic acromioclavicular joint injuries, partial claviculectomy is believed to be the best procedure, offering negligible morbidity and rapid return to function [14].
  • Both arthroscopic and open distal clavicle excisions provide significant pain reduction at 1 year with no significant difference in outcome measures between groups, except for VAS pain score improvement [17].
  • Routine distal clavicle excision is not absolutely necessary in patients with symptomatic acromioclavicular joint osteoarthritis undergoing arthroscopic rotator cuff repair [20].
  • Total claviculectomy is a possible treatment option for chronic clavicular dislocation, yielding excellent outcomes and high patient satisfaction [22].
  • 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].

Anatomy & Pathophysiology

  • 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 [29].
  • Normative kinematic values of scapulothoracic movements in the shoulder girdle have been provided [30].
  • No reconstruction strategy completely restores the shoulder girdle to its preinjured state, although each technique restores different elements of joint kinematics [31].
  • The trapezoid and conoid ligaments have unique functions in normal shoulder kinematics because of their anatomic attachments [32].
  • Kinematic changes could be a potential source of pain and dysfunction in the shoulder with AC joint dislocation [33].
  • Scapular and clavicular kinematics were affected in AC separation models [34].
  • 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 [35].
  • 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 [36].
  • Anatomically, the pectoralis minor tendon provides sufficient tissue length, excursion, and width [37].
  • Biomechanically, the pectoralis minor tendon is as strong as the coracoacromial ligament [37].
  • No significant biomechanical differences in displacement or stiffness were seen between the anatomical landmark technique and the coracoid-based landmarks technique for coracoclavicular stabilization [38].
  • New surgical techniques continue to evolve as more biomechanical data emerge and kinematic understanding improves [39].
  • Emerging concepts and strategies regarding horizontal and rotational instability and scapular biomechanics aim to lay the foundation for future studies aimed at improving treatment outcomes and patient management [40].
  • Preliminary findings revealed no detectable differences between surgically reconstructed and uninjured sides in ACJ biomechanics, range of motion, and isometric strength [41].
  • Nonoperatively treated shoulders showed increased internal rotation, upward rotation, and posterior tilting [41].
  • Type I and II acromioclavicular joint disruptions impair long-term shoulder function in about half of patients 10 years after injury [43].
  • 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% [44].
  • Centre of pressure measurement detected sensorimotor functional deficits following surgical treatment of the shoulder joint in patients with confirmed successful clinical and functional outcomes [45].

Classification

  • 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 [50].
  • Methods to diagnose both superior and posterior translation of the clavicle need further debate [15].
  • Patients with displacement greater than 100% of the thickness of the distal clavicle had poorer postoperative clinical outcomes [6].
  • Horizontal instability of the clavicle is evident with distal clavicle resection of greater than 10 mm [11].
  • Simple excision of the outer end of the clavicle has yielded satisfactory results in this group of patients, with no residual upward displacement disturbing the patients [7].
  • 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 [13].
  • Severe chronic symptomatic AC joint separations (Rockwood types III through V) can be repaired entirely by arthroscopy safely and effectively by transferring the coracoacromial ligament with a bone block in the distal clavicle [48].
  • Incomplete excision and regrowth of the distal clavicle are the most common causes of revision [10].
  • The combination of distal clavicle resection and antibiotics halted the osteolysis, and the patient has remained symptom free at 10 months after surgery [1].
  • The case highlights the need to consider Gorham-Stout disease in patients presenting with massive osteolysis after shoulder surgery [3].

Clinical Presentation

  • Distal clavicle osteolysis can be mediated by Propionibacterium acnes [1].
  • Massive osteolysis may occur as a complication following shoulder surgery, such as posterior shoulder capsulorrhaphy [3].
  • Segmental fractures of the clavicle are easily missed and may present with acromioclavicular joint disruption [21].
  • Late loss of reduction is common in acromioclavicular joint dislocations [5].
  • Patients with displacement greater than 100% of the thickness of the distal clavicle have poorer postoperative clinical outcomes [6].
  • Subacromial osteolysis following hook plate fixation for acromioclavicular dislocation has a relatively high and variable incidence [12].
  • The primary factor influencing the reported incidence of subacromial osteolysis is the radiological assessment method [12].
  • Clavicular tunnel widening was observed in 70% of patients at final follow-up after coracoclavicular stabilization surgery [16].
  • Clavicular tunnel widening has a higher prevalence in chronic cases than in acute cases [16].
  • Radiological assessment may show a statistically significant immediate superior clavicular displacement after hardware removal following acromioclavicular joint stabilization, with an increased incidence in the first year following stabilization [18].
  • Distal clavicle fracture is a potential complication of misidentification of the AC joint and subsequent aggressive burring during shoulder arthroscopy [26].

Investigations

  • Distal clavicle resection combined with antibiotics halted osteolysis in a case of Propionibacterium acnes–mediated distal clavicular osteolysis [1].
  • Massive osteolysis after shoulder surgery requires consideration of Gorham-Stout disease as a diagnosis [3].
  • Late loss of reduction was common in acromioclavicular joint dislocations, while clavicular resection reliably produced significant improvement in patients with persistent pain or posttraumatic arthritis [5].
  • 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].
  • Simple excision of the outer end of the clavicle yielded satisfactory results in patients with acromioclavicular joint dislocation and subluxation, with no residual upward displacement disturbing the patients [7].
  • Subacromial osteolysis following hook plate fixation for acromioclavicular dislocation has a relatively high and variable incidence, with the primary factor influencing the reported incidence being the radiological assessment method [12].
  • Radiological assessment showed a statistically significant immediate superior clavicular displacement after hardware removal following acromioclavicular joint stabilization using a suspensory fixation system, with an increased incidence in the first year following stabilization [18].
  • Weighted stress radiographs significantly increased the measured elevation of the clavicle and the coracoclavicular distance compared to non-weighted views in acute acromioclavicular joint dislocations [47].
  • A high index of suspicion is needed to diagnose bone osteolysis following acromioclavicular joint reconstruction using synthetic ligament early before irretrievable bone loss occurs [54].
  • Segmental fractures of the clavicle are easily missed [21].

Treatment

  • 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].
  • 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].
  • Clavicular resection reliably produced significant improvement in patients with persistent pain or posttraumatic arthritis following late loss of reduction after acromioclavicular joint dislocation [5].
  • Simple excision of the outer end of the clavicle yielded satisfactory results in patients with acromioclavicular joint dislocation, with no residual upward displacement disturbing the patients [7].
  • 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].
  • Ipsilateral os acromiale may be a relative contraindication to the clavicle hook plate [46].
  • 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 [49].
  • Less residual pain was found using the arthroscopic technique compared with the open procedure for distal clavicle excision [49].
  • High-level studies on treatment modalities for acromioclavicular joint pain are limited [52].

Complications

  • 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].
  • Gorham-Stout disease should be considered in patients presenting with massive osteolysis after shoulder surgery [3].
  • Incomplete excision and regrowth of the distal clavicle are the most common causes of revision following distal clavicle resection [10].
  • 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].
  • 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].
  • Late loss of reduction was common in patients with acromioclavicular joint dislocation, while clavicular resection reliably produced significant improvement in patients with persistent pain or posttraumatic arthritis [5].
  • Simple excision of the outer end of the clavicle has yielded satisfactory results in patients with acromioclavicular joint dislocation, with no residual upward displacement disturbing the patients [7].
  • 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].
  • Asymptomatic ossification of the coracoclavicular ligaments can occur 15 years postoperatively following anatomic reduction of acute acromioclavicular joint separations [19].

Recovery

  • 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].
  • Incomplete excision and regrowth of the distal clavicle are the most common causes of revision after acromioclavicular joint resection [10].
  • 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].
  • Patients with displacement greater than 100% of the thickness of the distal clavicle had poorer postoperative clinical outcomes following acromioclavicular joint dislocation treated with the endobutton device [6].
  • 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].
  • Radiological assessment showed a statistically significant immediate superior clavicular displacement after hardware removal following acromioclavicular joint stabilization using a suspensory fixation system, with an increased incidence in the first year following stabilization, though this may not negatively influence the results of acromioclavicular joint stabilization in a clinically relevant way [18].
  • 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].
  • The combination of distal clavicle resection and antibiotics halted Propionibacterium acnes–mediated distal clavicular 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. [1] (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. [2] (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. [3] (10.1016/j.jse.2012.05.024)
  • [L5] In appropriately selected patients, open or arthroscopic distal clavicle resection is necessary to relieve symptoms. [4] (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. [5] (10.2106/00004623-198769070-00013)
  • [L3] Patients with displacement greater than 100% of the thickness of the distal clavicle had poorer postoperative clinical outcomes. [6] (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. [8] (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. [9] (10.1016/j.arthro.2018.03.004)
  • [L4] Incomplete excision and regrowth of the distal clavicle are the most common causes of revision. [10] (10.1016/j.arthro.2009.06.010)
  • [L4] Horizontal instability of the clavicle is evident with distal clavicle resection of greater than 10 mm. [11] (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. [12] (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. [13] (10.2106/00004623-196345080-00024)
  • [L4] Methods to diagnose both superior and posterior translation of the clavicle need further debate. [15] (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. [16] (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. [17] (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. [18] (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. [19] (10.1177/03635465251355958)
  • [L2] Routine distal clavicle excision is not absolutely necessary, even in patients with symptomatic ACJ osteoarthritis. [20] (10.1007/s00167-020-06098-y)
  • [Case_report] The case highlights that segmental fractures of the clavicle are easily missed. [21] (10.1177/1758573214564496)
  • [Case_report] Total claviculectomy is a possible treatment option for chronic clavicular dislocation with excellent outcomes and high patient satisfaction. [22] (10.1016/j.xrrt.2021.03.007)
  • [L4] Excellent clinical results were achieved, decreasing the risk of recurrent distal clavicle instability. [23] (10.1186/1471-2474-10-6)
  • [L4] Satisfactory outcome depends upon restoring the stability of the clavicle as well as the acromioclavicular joint. [24] (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. [25] (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. [26] (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. [27] (10.1016/j.jse.2006.07.007)
  • [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. [29] (10.1177/17585732221090226)
  • [L5] This study provided normative kinematic values of scapulothoracic movements in the shoulder girdle. [30] (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. [31] (10.1177/03635465221095231)
  • [L5] The trapezoid and conoid ligaments have unique functions in normal shoulder kinematics because of their anatomic attachments. [32] (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. [33] (10.1177/0363546512458571)
  • [L5] Scapular and clavicular kinematics were affected in AC separation models. [34] (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. [35] (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. [36] (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. [37] (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. [38] (10.1177/23259671221132541)
  • [L5] New surgical techniques continue to evolve as more biomechanical data emerge and kinematic understanding improves. [39] (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. [40] (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. [41] (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. [43] (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%. [44] (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. [45] (10.1007/s00167-021-06751-0)
  • [L4] Ipsilateral os acromiale may be a relative contraindication to the clavicle hook plate. [46] (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. [47] (10.1016/j.jseint.2023.06.011)
  • [L4] Severe chronic symptomatic AC joint separations (Rockwood types III through V) can be repaired entirely by arthroscopy safely and effectively by transferring the coracoacromial ligament with a bone block in the distal clavicle. [48] (10.1016/j.arthro.2009.08.008)
  • [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. [49] (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. [50] (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. [51] (10.1155/2022/8706638)
  • [L2] High-level studies on treatment modalities for acromio-clavicular joint pain are limited. [52] (10.1177/1758573217700839)
  • [L4] A high index of suspicion is needed to diagnose such complications early before irretrievable bone loss to osteolysis. [54] (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. [56] (10.1177/03635465010290060401)

References

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[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

[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

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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.